Updated on 2026/03/11

写真a

 
IIMA Mami
 
Organization
Graduate School of Medicine Designated Professor
Title
Designated Professor

Research Areas 2

  1. Life Science / Tumor diagnostics and therapeutics  / Breast Cancer

  2. Life Science / Radiology

Research History 2

  1. 名古屋大学 大学院医学系研究科 新規低侵襲画像診断法基盤開発研究寄附講座   特任教授

    2024.4

  2. 京都大学医学部附属病院 先端医療研究開発機構 / 放射線診断科   特定講師

    2024.3

Professional Memberships 10

  1. Radiological Society of North America

  2. 臨床試験学会

  3. European Congress of Radiology

  4. European Society of Breast Imaging

  5. 日本磁気共鳴医学会

  6. 日本放射線科専門医会・医会

  7. 日本医学放射線学会

  8. 日本乳癌検診学会

  9. 日本乳癌学会

  10. International Society for Magnetic Resonance in Medicine

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Committee Memberships 24

  1. 日本学術振興会   特別研究員等審査会 審査委員  

    2025   

  2. European Journal of Radiology   section editor  

    2024   

  3.   Scientific Reports Editorial Board  

    2024   

  4. ISMRM Study Group Review Committee   member  

    2024   

  5. 公益財団法人 日本医学放射線学会   編集委員会 委員  

    2024   

  6.   国際磁気共鳴医学会(ISMRM) 拡散強調スタディグループ 運営委員会 Chair  

    2024 - 2025   

  7.   ISMRM IVIM Workshop Organizing Comittee Member -ISMRM Workshop on Moving Forward with Intravoxel Incoherent Motion Modeling for Diffusion-Weighted MRI: An Attempt at Consensus-  

    2023   

  8. バイオインダストリー協会(JBA)   バイオサイエンスとインダストリー(B&I) 編集委員  

    2023   

  9. BJR|Artificial Intelligence   senior editor  

    2023   

  10.   ISMRM Diffusion Study Group Workshop Co-chair (Mami Iima, Susie Huang) -ISMRM Workshop on 40 years of Diffusion: Past, Present and Future Perspectives-  

    2023 - 2025   

  11.   ISMRM Diffusion Study Group Vice-Chair  

    2023 - 2024   

  12. Society of Advanced Medical Imaging   Facilitator  

    2022.1   

  13. Korean Journal of Radiology   Editorial Board  

    2022.1   

  14.   NMR in Biomedicine 編集委員  

    2022   

  15. 日本磁気共鳴医学会   広報委員  

    2022   

  16. 日本磁気共鳴医学会大会   プログラム委員  

    2022   

  17.   a member of the Annual Meeting Program Committee (AMPC) of the ISMRM  

    2022 - 2025   

  18. 京都大学 「世界視力を備えた次世代トップ研究者育成プログラム」(通称L-INSIGHT)   第3回 L-INSIGHTフェロー  

    2022 - 2024.3   

  19. 日本磁気共鳴医学会   代議員  

    2021.9   

  20.   日本乳癌学会診療ガイドライン委員会 検診・診断小委員会 システマティック・レビュー委員  

    2021 - 2024.3   

  21. 日本医学放射線学会   Japan Quantitative Imaging Biomarker Alliance J-QIBA委員  

    2020   

  22. JSPS 産学協力委員会 R021食と未病マーカー委員会   委員  

    2020   

  23.   JRS画像診断ガイドライン(乳房) 委員  

       

  24. Tomography   Editorial Board  

       

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Awards 4

  1. Silver Prize

    2025.8   ISMRM-JPC2025   Automated Breast Cancer Detection and Classification Using Machine Learning on DWI

    Kaito Nonoyama, Mami Iima, Ryosuke Mizuno, Keiho Imanishi, Hiroko Satake, Rintaro Ito, Masako Kataoka, Shinji Naganawa

  2. 2024 Radiology Editor’s Recognition Award for reviewing with Distinction, 北米放射線学会

    2025.1  

  3. 融合研究着想コンテストFY2024 審査員賞

    2024.9   L-INSIGHT   我々はどこから来たのか 我々は何者か 我々は宇宙へ⾏くのか

    代表者, 藤井悠里(人間, 環境学研究科, 山田真太郎, 白眉センター, 医学研究科, 共同提案者, 藤井俊博, 大学院理学研究科, 飯間麻美, 大学院医学系研究科, 渡邉 翼, 複合原子力科学研究所, 松本 徹, 白眉センター

  4. 2023 Radiology Editor’s Recognition Award for reviewing with Distinction

    2024.2   Radiological Society of North America  

 

Papers 41

  1. Cervical cancer in the modern era: cutting-edge strategies for diagnosis and treatment Open Access

    Tsukasa Saida, Takashi Saitoh, Ayumi Shikama, Michitaka Hayashi, Taichi Ishikawa, Mami Iima, Takahito Nakajima, Shinji Naganawa

    Japanese Journal of Radiology   Vol. 44 ( 3 ) page: 491 - 507   2026.3

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    DOI: 10.1007/s11604-025-01897-0

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  2. Diagonal DWI: A Time‐Efficient Alternative to 3‐Scan Trace DWI for Breast Lesion Evaluation at 3.0‐T MRI—A Phantom Study and Clinical Assessment

    Yusuke Jo, Yuki Sato, Mami Iima, Hiroko Satake, Yunhao Zhang, Yutaka Kato, Satoko Ishigaki, Ryota Hyodo, Aki Mano, Yoshito Ichiba, Shinji Naganawa

    Journal of Magnetic Resonance Imaging   Vol. 63 ( 3 ) page: 711 - 718   2026.3

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    DOI: 10.1002/jmri.70155

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  3. Breast cancer imaging without gadolinium-based contrast agent: A review of current applications and future trends. International journal

    Maya Honda, Mami Iima, Masako Kataoka, Daiju Ueda, Tsukasa Saida, Kentaro Nishioka, Ryo Kurokawa, Satoru Ide, Masahiro Yanagawa, Tadashi Watabe, Kenji Hirata, Rintaro Ito, Seitaro Oda, Koji Takumi, Mariko Kawamura, Shunsuke Sugawara, Keitaro Sofue, Akihiko Sakata, Shinji Naganawa

    Diagnostic and interventional imaging   Vol. 107 ( 2 ) page: 51 - 61   2026.2

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    Dynamic contrast-enhanced magnetic resonance imaging remains a cornerstone of breast cancer diagnosis, yet concerns regarding the safety, environmental impact, and cost of gadolinium-based contrast agents are driving the development of gadolinium-based contrast agent-free alternatives. This review outlines emerging non-contrast imaging modalities that support a more sustainable approach to breast cancer diagnosis. Advanced MRI techniques, such as diffusion-weighted imaging and synthetic MRI, provide detailed tissue characterization without the need for contrast agents. In computed tomography (CT), innovations including dual-energy CT and photon-counting detector CT are improving lesion detection and characterization, with photon-counting detector CT offering exceptional spatial resolution. Molecular imaging with positron emission tomography is also advancing beyond 18F-fluorodeoxyglucose, incorporating dedicated high-resolution systems and novel tracers targeting specific biomarkers, such as 16α-18F-fluoro-17β-estradiol for estrogen receptors, fibroblast activation protein inhibitors, and human epidermal growth factor receptor 2-targeted agents. The future of breast imaging is likely to adopt a multimodal strategy, combining these innovations to deliver more accurate, personalized, and sustainable patient care.

    DOI: 10.1016/j.diii.2025.10.004

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  4. Early washout in encapsulated papillary carcinoma on ultrafast DCE-MRI

    Yusuke Jo, Mami Iima, Hiroko Satake

    Japanese Journal of Radiology   Vol. 44 ( 2 ) page: 443 - 446   2026.2

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    DOI: 10.1007/s11604-025-01901-7

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  5. ESR Essentials: Perfusion MRI-practice recommendations by the European Society for Magnetic Resonance in Medicine and Biology Open Access

    van Houdt, PJ; Václavu, L; Sourbron, S; Shalom, ES; Federau, C; Iima, M; Liu, MM; Knutsson, L; Wirestam, R; Günther, M; van Osch, MJP; van der Heijden, RA

    EUROPEAN RADIOLOGY     2026.1

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    Abstract: Perfusion MRI techniques—including dynamic susceptibility contrast (DSC) MRI, dynamic contrast-enhanced (DCE) MRI, arterial spin labeling (ASL) MRI, and intravoxel incoherent motion (IVIM) MRI—hold strong potential as imaging techniques for diagnosing, staging, and monitoring disease across a range of clinical applications. However, clinical adoption, especially of quantitative parameters, remains variable across techniques. Key barriers to broader implementation include a lack of standardized acquisition and analysis protocols, leading to poor reproducibility and reduced clinical confidence. Additionally, limited awareness and understanding of certain techniques among radiologists contribute to underutilization in practice. This work provides practice recommendations to support radiologists in integrating perfusion MRI into routine clinical workflows. It includes guidance on technique selection, acquisition, and analysis, supported by a flowchart outlining typical imaging pathways. These efforts align with ongoing initiatives such as the Quantitative Medical Imaging Coalition (formerly QIBA) and the ISMRM Open Science Initiative for Perfusion Imaging (OSIPI), which are developing standards and tools to enhance reproducibility and clinical utility. Ultimately, the successful adoption of state-of-the-art perfusion MRI depends on close collaboration between clinicians, researchers, and industry stakeholders to ensure robust, standardized, and clinically meaningful application. Key Points: Perfusion MRI parameters hold great promise as imaging biomarkers, but their clinical adoption, especially of quantitative parameters, remains variable across perfusion MRI techniques. An overview of perfusion MRI techniques, explaining the physics, illustrating clinical applications, and addressing common technical challenges, is provided to support perfusion MRI use in clinical practice. Successful adoption of state-of-the-art perfusion MRI depends on close collaboration between clinicians, researchers, and industry stakeholders to ensure robust, standardized, and clinically meaningful applications for patient care.

    DOI: 10.1007/s00330-025-12306-5

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  6. Correction: Honda et al. Visual Evaluation of Ultrafast MRI in the Assessment of Residual Breast Cancer After Neoadjuvant Systemic Therapy: A Preliminary Study Association with Subtype. Tomography 2022, 8, 1522–1533

    Maya Honda, Masako Kataoka, Mami Iima, Rie Ota, Akane Ohashi, Ayami Ohno Kishimoto, Kanae Kawai Miyake, Marcel Dominik Nickel, Yosuke Yamada, Masakazu Toi, Yuji Nakamoto

    Tomography     2026.1

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    DOI: 10.3390/tomography12010006

  7. Recent Advances in Musculoskeletal Radiology: Bridging Innovation and Clinical Application

    Satoru Ide, Takatoshi Aoki, Ryo Kurokawa, Masahiro Yanagawa, Tsukasa Saida, Shunsuke Sugawara, Kentaro Nishioka, Seitaro Oda, Tadashi Watabe, Kenji Hirata, Rintaro Ito, Daiju Ueda, Koji Takumi, Maya Honda, Akihiko Sakata, Mariko Kawamura, Keitaro Sofue, Mami Iima, Shinji Naganawa

    Magnetic Resonance in Medical Sciences     2025.12

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    DOI: 10.2463/mrms.rev.2025-0150

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  8. Artificial superintelligence alignment in healthcare. Open Access

    Daiju Ueda, Shannon L Walston, Ryo Kurokawa, Tsukasa Saida, Maya Honda, Mami Iima, Tadashi Watabe, Masahiro Yanagawa, Kentaro Nishioka, Keitaro Sofue, Akihiko Sakata, Shunsuke Sugawara, Mariko Kawamura, Rintaro Ito, Koji Takumi, Seitaro Oda, Kenji Hirata, Satoru Ide, Shinji Naganawa

    Japanese journal of radiology     2025.11

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    The emergence of Artificial Superintelligence (ASI) in healthcare presents unprecedented opportunities for revolutionizing diagnostics, treatment planning, and population health management, but also introduces critical risks if these systems are not properly aligned with human values and clinical objectives. This review examines the theoretical foundations of ASI and the alignment problem in healthcare contexts, exploring how misaligned Artificial Intelligence (AI) systems could optimize for wrong objectives or pursue harmful strategies leading to patient harm and systemic failures. Current challenges in AI alignment are illustrated through real-world examples from radiology and clinical decision-making, where algorithms have demonstrated concerning biases, generalizability failures, and optimization for inappropriate proxy measures. The paper analyzes key alignment challenges including objective complexity and technical pitfalls, bias and fairness issues in healthcare data, ethical integration concerns involving compassion and patient autonomy, and system-level policy challenges around regulation and liability. Technical alignment strategies are discussed including reinforcement learning from human feedback, interpretability requirements, formal verification methods, and adversarial testing approaches. Normative alignment solutions encompass ethical frameworks, professional standards, patient engagement protocols, and multi-level governance structures spanning institutional, national, and international coordination. The review emphasizes that successful ASI alignment in healthcare requires combining cutting-edge AI research with fundamental medical ethics, noting that while proper alignment could enable transformative health improvements and medical breakthroughs, misalignment risks undermining the core purpose of medicine. The stakes of this alignment challenge are characterized as among the highest in both technology and ethics, with implications extending from individual patient safety to public trust and potentially existential risks.

    DOI: 10.1007/s11604-025-01907-1

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  9. Illuminating radiogenomic signatures in pediatric-type diffuse gliomas: insights into molecular, clinical, and imaging correlations. Part I: high-grade group Open Access

    Kurokawa, R; Hagiwara, A; Ueda, D; Ito, R; Saida, T; Honda, M; Nishioka, K; Sakata, A; Yanagawa, M; Takumi, K; Oda, S; Ide, S; Sofue, K; Sugawara, S; Watabe, T; Hirata, K; Kawamura, M; Iima, M; Naganawa, S

    RADIOLOGIA MEDICA   Vol. 130 ( 11 ) page: 1871 - 1887   2025.11

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    Recent advances in molecular genetics have revolutionized the classification of pediatric-type high-grade gliomas in the 2021 World Health Organization central nervous system tumor classification. This narrative review synthesizes current evidence on the following four tumor types: diffuse midline glioma, H3 K27-altered; diffuse hemispheric glioma, H3 G34-mutant; diffuse pediatric-type high-grade glioma, H3-wildtype and IDH-wildtype; and infant-type hemispheric glioma. We conducted a comprehensive literature search for articles published through January 2025. For each tumor type, we analyze characteristic clinical presentations, molecular alterations, conventional and advanced magnetic resonance imaging features, radiological-molecular correlations, and current therapeutic approaches. Emerging radiogenomic approaches utilizing artificial intelligence, including radiomics and deep learning, show promise in identifying imaging biomarkers that correlate with molecular features. This review highlights the importance of integrating radiological and molecular data for accurate diagnosis and treatment planning, while acknowledging limitations in current methodologies and the need for prospective validation in larger cohorts. Understanding these correlations is crucial for advancing personalized treatment strategies for these challenging tumors.

    DOI: 10.1007/s11547-025-02078-9

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  10. Ultrafast MRI and diffusion-weighted imaging: a review of morphological evaluation and image quality in breast MRI Open Access

    Maya Honda, Masako Kataoka, Mami Iima, Marcel Dominik Nickel, Tsutomu Okada, Yuji Nakamoto

    Japanese Journal of Radiology   Vol. 43 ( 11 ) page: 1761 - 1777   2025.11

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    Breast magnetic resonance imaging (MRI) is an essential tool for evaluating breast lesions, with dynamic contrast-enhanced (DCE) MRI being considered the reference standard. However, conventional DCE-MRI has limitations, including long scan times, high costs, and variable specificity leading to unnecessary biopsies. Emerging techniques such as ultrafast dynamic contrast-enhanced (UF-DCE) MRI and diffusion-weighted imaging (DWI) have recently received attention as possible alternatives. UF-DCE MRI achieves high temporal resolution, improving lesion conspicuity while reducing motion artifacts and background parenchymal enhancement. Advanced acceleration methods, including view sharing and compressed sensing, enhance temporal resolution while maintaining image quality. DWI, a contrast agent-free technique that can be used to assess tissue cellularity, provides high specificity in the differentiation of benign from malignant lesions. Recent developments in DWI, such as readout-segmented echo planar imaging, reduced field of view, and simultaneous multi-slice techniques, have significantly improved spatial resolution and reduced artifacts. These advancements enable morphological assessment and hold the potential for replacing or complementing conventional DCE-MRI, thus reducing patient burden and improving accessibility. Future research should focus on optimizing imaging protocols and integrating artificial intelligence to enhance diagnostic performance. This review discusses the principles, technological advancements, and clinical applications of UF-DCE MRI and DWI, with a particular focus on morphological evaluation and image quality, emphasizing their role in improving the efficiency of breast imaging while maintaining accuracy.

    DOI: 10.1007/s11604-025-01826-1

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  11. Japanese Radiology 2025 Updates

    Mami Iima, Tsukasa Saida, Yoshitake Yamada, Ryo Kurokawa, Daiju Ueda, Maya Honda, Kentaro Nishioka, Rintaro Ito, Keitaro Sofue, Shinji Naganawa

    Canadian Association of Radiologists Journal     page: 8465371251374557   2025.10

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    DOI: 10.1177/08465371251374557

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  12. Advances in renal cancer: diagnosis, treatment, and emerging technologies. International journal

    Tsukasa Saida, Mami Iima, Rintaro Ito, Daiju Ueda, Kentaro Nishioka, Ryo Kurokawa, Mariko Kawamura, Kenji Hirata, Maya Honda, Koji Takumi, Satoru Ide, Shunsuke Sugawara, Tadashi Watabe, Akihiko Sakata, Masahiro Yanagawa, Keitaro Sofue, Seitaro Oda, Shinji Naganawa

    La Radiologia medica   Vol. 130 ( 10 ) page: 1540 - 1560   2025.10

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    This review provides a comprehensive overview of current practices and recent advancements in the diagnosis and treatment of renal cancer. It introduces updates in histological classification and explains the imaging characteristics of each tumour based on these changes. The review highlights state-of-the-art imaging modalities, including magnetic resonance imaging, computed tomography, positron emission tomography, and ultrasound, emphasising their crucial role in tumour characterisation and optimising treatment planning. Emerging technologies, such as radiomics and artificial intelligence, are also discussed for their transformative impact on enhancing diagnostic precision, prognostic prediction, and personalised patient management. Furthermore, the review explores current treatment options, including minimally invasive techniques such as cryoablation, radiofrequency ablation, and stereotactic body radiation therapy, as well as systemic therapies such as immune checkpoint inhibitors and targeted therapies.

    DOI: 10.1007/s11547-025-02066-z

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  13. Photon-counting detector computed tomography in thoracic oncology: revolutionizing tumor imaging through precision and detail. International journal

    Masahiro Yanagawa, Midori Ueno, Rintaro Ito, Daiju Ueda, Tsukasa Saida, Ryo Kurokawa, Koji Takumi, Kentaro Nishioka, Shunsuke Sugawara, Satoru Ide, Maya Honda, Mami Iima, Mariko Kawamura, Akihiko Sakata, Keitaro Sofue, Seitaro Oda, Tadashi Watabe, Kenji Hirata, Shinji Naganawa

    Diagnostic and interventional radiology (Ankara, Turkey)     2025.9

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    Photon-counting detector computed tomography (PCD-CT) is an emerging imaging technology that promises to overcome the limitations of conventional energy-integrating detector (EID)-CT, particularly in thoracic oncology. This narrative review summarizes technical advances and clinical applications of PCD-CT in the thorax with emphasis on spatial resolution, dose-image-quality balance, and intrinsic spectral imaging, and it outlines practical implications relevant to thoracic oncology. A literature review of PubMed through May 31, 2025, was conducted using combinations of "photon counting," "computed tomography," "thoracic oncology," and "artificial intelligence." We screened the retrieved records and included studies with direct relevance to lung and mediastinal tumors, image quality, radiation dose, spectral/iodine imaging, or artificial intelligence-based reconstruction; case reports, editorials, and animal-only or purely methodological reports were excluded. PCD-CT demonstrated superior spatial resolution compared with EID-CT, enabling clearer visualization of fine pulmonary structures, such as bronchioles and subsolid nodules; slice thicknesses of approximately 0.4 mm and ex vivo resolvable structures approaching 0.11 mm have been reported. Across intraindividual clinical comparisons, radiation-dose reductions of 16%-43% have been achieved while maintaining or improving diagnostic image quality. Intrinsic spectral imaging enables accurate iodine mapping and low-keV virtual monoenergetic images and has shown quantitative advantages versus dual-energy CT in phantoms and early clinical work. Artificial intelligence-based deep-learning reconstruction and super-resolution can complement detector capabilities to reduce noise and stabilize fine-structure depiction without increasing dose. Potential reductions in contrast volume are biologically plausible given improved low-keV contrast-to-noise ratio, although clinical dose-finding data remain limited, and routine K-edge imaging has not yet translated to clinical thoracic practice. In conclusion, PCD-CT provides higher spatial and spectral fidelity at lower or comparable doses, supporting earlier and more precise tumor detection and characterization; future work should prioritize outcome-oriented trials, protocol harmonization, and implementation studies aligned with "Green Radiology".

    DOI: 10.4274/dir.2025.253550

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  14. Illuminating radiogenomic signatures in pediatric-type diffuse gliomas: insights into molecular, clinical, and imaging correlations. Part II: low-grade group. International journal Open Access

    Ryo Kurokawa, Akifumi Hagiwara, Rintaro Ito, Daiju Ueda, Tsukasa Saida, Akihiko Sakata, Kentaro Nishioka, Shunsuke Sugawara, Koji Takumi, Tadashi Watabe, Satoru Ide, Mariko Kawamura, Keitaro Sofue, Kenji Hirata, Maya Honda, Masahiro Yanagawa, Seitaro Oda, Mami Iima, Shinji Naganawa

    La Radiologia medica   Vol. 130 ( 9 ) page: 1503 - 1515   2025.9

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    The fifth edition of the World Health Organization classification of central nervous system tumors represents a significant advancement in the molecular-genetic classification of pediatric-type diffuse gliomas. This article comprehensively summarizes the clinical, molecular, and radiological imaging features in pediatric-type low-grade gliomas (pLGGs), including MYB- or MYBL1-altered tumors, polymorphous low-grade neuroepithelial tumor of the young (PLNTY), and diffuse low-grade glioma, MAPK pathway-altered. Most pLGGs harbor alterations in the RAS/MAPK pathway, functioning as "one pathway disease". Specific magnetic resonance imaging features, such as the T2-fluid-attenuated inversion recovery (FLAIR) mismatch sign in MYB- or MYBL1-altered tumors and the transmantle-like sign in PLNTYs, may serve as non-invasive biomarkers for underlying molecular alterations. Recent advances in radiogenomics have enabled the differentiation of BRAF fusion from BRAF V600E mutant tumors based on magnetic resonance imaging characteristics. Machine learning approaches have further enhanced our ability to predict molecular subtypes from imaging features. These radiology-molecular correlations offer potential clinical utility in treatment planning and prognostication, especially as targeted therapies against the MAPK pathway emerge. Continued research is needed to refine our understanding of genotype-phenotype correlations in less common molecular alterations and to validate these imaging biomarkers in larger cohorts.

    DOI: 10.1007/s11547-025-02049-0

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  15. Recent advances in theranostics and oncology PET: emerging radionuclides and targets. Open Access

    Tadashi Watabe, Kenji Hirata, Mami Iima, Masahiro Yanagawa, Tsukasa Saida, Akihiko Sakata, Satoru Ide, Maya Honda, Ryo Kurokawa, Kentaro Nishioka, Mariko Kawamura, Rintaro Ito, Koji Takumi, Seitaro Oda, Shunsuke Sugawara, Keitaro Sofue, Daiju Ueda, Shinji Naganawa

    Annals of nuclear medicine   Vol. 39 ( 9 ) page: 909 - 921   2025.9

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    Theranostics, a novel integrated approach that combines cancer diagnosis and therapy by switching the radionuclide, has attracted growing attention. Various oncology PET probes other than FDG have been developed for the highly sensitive and precise detection of many types of cancer with the advancements in PET scanners, supporting the innovative development in theranostics. In therapeutic applications, radioligand therapy targeting somatostatin receptors (SSTR) and prostate-specific membrane antigen (PSMA) has already demonstrated significant clinical benefits. Terbium-161 (161Tb) has emerged as a new beta and Auger electron emitter, showing greater therapeutic efficacy compared to 177Lu. Alpha emitters, such as astatine (211At), are currently being evaluated in investigator-initiated clinical trials, with preliminary efficacy data reported for [211At]NaAt in patients with radioiodine-refractory thyroid cancer. Novel pan-tumor targeting agents, such as TROP-2, Nectin-4, LAT1, GPC-1, and EphA2, are also under development, and clinical translation of radioligand therapy is anticipated. These innovations in theranostics are expected to further broaden the scope of precision medicine in oncology.

    DOI: 10.1007/s12149-025-02090-z

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  16. TOP GUN initiative: advancing interdisciplinary collaboration in radiology. Open Access

    Mami Iima, Shinji Naganawa

    Japanese journal of radiology   Vol. 43 ( 8 ) page: 1229 - 1230   2025.8

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  17. Contribution of white matter microstructure to diffusion tensor image analysis along perivascular space in obstructive sleep apnea. Open Access

    Toshiaki Taoka, Kunihiro Iwamoto, Seiko Miyata, Rintaro Ito, Koji Kamagata, Rei Nakamichi, Toshiki Nakane, Mami Iima, Hiroshige Fujishiro, Masashi Ikeda, Kazushige Ichikawa, Akifumi Kamiunten, Nobuyasu Ichinose, Junko Kikuta, Shigeki Aoki, Shinji Naganawa

    Japanese journal of radiology   Vol. 43 ( 12 ) page: 1926 - 1941   2025.7

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    PURPOSE: We aimed to evaluate whether the ALPS index derived from diffusion tensor image analysis along the perivascular space (DTI-ALPS) is influenced by white matter fibres within the analysis region, particularly commissural fibres from the corpus callosum that traverse this area in psychiatric patients with suspected obstructive sleep apnea (OSA). We also investigated associations between diffusion-based parameters, sleep-related data, and neurofluid-related imaging metrics. METHODS: Fifty participants with OSA underwent brain magnetic resonance imaging and polysomnography, including diffusion tensor and structural sequences. Among them, 8 participants had no psychiatric comorbidities, while the remaining 42 had various psychiatric disorders in addition to OSA. Diffusion-based parameters were obtained, and both the original and variant ALPS index were calculated. Correlation analyses were conducted with sleep-related data and neurofluid-related imaging parameters, including choroid plexus volume (CPV) and volume of white matter lesion burden (WMHV). Mediation analyses were also performed to explore the influence of white matter diffusivity on the perivascular diffusivity index. RESULTS: The ALPS index showed weak to moderate correlations with multiple sleep-related variables. It also correlated with CPV and WMHV. Mediation analyses demonstrated that diffusivity within white matter fibres was associated with the ALPS index. Moreover, variant ALPS indices measured in the corpus callosum may reflect fluid motion in the direction of perivascular spaces. CONCLUSION: These findings suggest that the ALPS index is influenced by both diffusivity along perivascular spaces and white matter microstructure, particularly commissural fibres. Although it should not be regarded as a highly specific marker of perivascular space function, variant indices support partial perivascular contribution. Furthermore, associations with sleep and neurofluid-related metrics imply that white matter architecture and inter-fibre spaces may serve as plausible routes for interstitial fluid flow.

    DOI: 10.1007/s11604-025-01838-x

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  18. Radiomics-based Machine Learning Prediction of Neoadjuvant Chemotherapy Response in Breast Cancer Using Physiologically Decomposed Diffusion-weighted MRI. International journal Open Access

    Maya Gilad, Savannah C Partridge, Mami Iima, Rebecca Rakow-Penner Md, Moti Freiman

    Radiology. Imaging cancer   Vol. 7 ( 4 ) page: e240312   2025.7

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    Purpose To evaluate the performance of a machine learning model developed using radiomics data derived from physiologically decomposed diffusion-weighted MRI data for predicting pathologic complete response (pCR) following neoadjuvant chemotherapy for breast cancer compared with baseline and benchmark models. Materials and Methods This retrospective study included data from the Breast Multiparametric MRI for prediction of neoadjuvant chemotherapy Response (BMMR2) challenge dataset, comprising longitudinal multiparametric breast MRI studies (diffusion-weighted imaging [DWI] and dynamic contrast-enhanced MRI) from participants enrolled in the I-SPY 2/ACRIN 6698 trial (ClinicalTrials.gov: NCT01042379). Piecewise linear physiologic decomposition was applied to DWI data (PD DWI) to isolate pseudo-diffusion, pure-diffusion, and pseudo-diffusion fraction components for radiomics feature extraction. These features were used to develop a boosted decision tree model to predict pCR following neoadjuvant chemotherapy. Model performance was compared with performance of baseline models, including data on tumor size and mean apparent diffusion coefficient, and the BMMR2 challenge benchmark model using area under the receiver operating characteristic curve, F1 score, and positive and negative predictive values. Model calibration was assessed via the Brier score, and a decision curve analysis was performed to estimate the potential reduction in unnecessary interventions when using the proposed model. Results The study included multiparametric MRI scans from 190 female participants (mean age ± SD, 48.4 years ± 10.5). PD DWI achieved the highest area under the receiver operating characteristic curve (0.89, 95% CI: 0.81, 0.96) among all evaluated models, demonstrating statistically significant improvements over baseline approaches (all P < .04). Decision curve analysis showed that the PD DWI model provided a greater net benefit compared with the BMMR2 challenge benchmark model (0.17, 95% CI: 0.13, 0.21 vs 0.09, 95% CI: 0.05, 0.13; P < .001). Conclusion A machine learning model using radiomics data derived from PD DWI achieved higher performance than baseline and benchmark models in predicting pCR following neoadjuvant chemotherapy for breast cancer. Keywords: Image Postprocessing, MR-Diffusion Weighted Imaging, Breast, Tumor Response, Experimental Investigations ClinicalTrials.gov: NCT01042379 © RSNA, 2025.

    DOI: 10.1148/rycan.240312

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  19. The glymphatic system in oncology: from the perspective of a radiation oncologist. International journal Open Access

    Kentaro Nishioka, Mariko Kawamura, Mami Iima, Daiju Ueda, Rintaro Ito, Tsukasa Saida, Ryo Kurokawa, Koji Takumi, Akihiko Sakata, Satoru Ide, Maya Honda, Masahiro Yanagawa, Shunsuke Sugawara, Seitaro Oda, Tadashi Watabe, Keitaro Sofue, Kenji Hirata, Shinji Naganawa

    Journal of radiation research   Vol. 66 ( 4 ) page: 343 - 353   2025.7

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    The brain and spinal cord, which constitute the central nervous system, were historically considered immune-privileged sites, as it was believed they lacked an equivalent to the systemic lymphatic system. However, in 2013, a pathway facilitating the clearance of waste products through the brain parenchyma via the perivascular space was proposed, garnering attention as the 'glymphatic system'. Similar to the systemic lymphatic system, the glymphatic system plays a critical role in immune responses and has been implicated not only in Alzheimer's disease and inflammatory brain disorders but also in conditions such as hydrocephalus and glaucoma, which are associated with cerebrospinal fluid circulation impairments. Recent studies have suggested that dysfunction of the glymphatic system may promote the progression of brain tumors and reduce the efficacy of immune responses and pharmacological therapies targeting tumors. Radiotherapy is a major treatment option for brain tumors; however, while it can enhance immune responses against tumors, it may also suppress these responses at the same time. Additionally, cranial irradiation has been suggested to impair the function of the glymphatic system. This review provides an overview of the structure and functional evaluation methods of the glymphatic system, summarizes the effects of its dysfunction on brain tumor treatment, and explores recent findings on the impact of radiation therapy on glymphatic system functioning. Lastly, it also explores the potential for radiation therapy strategies that account for their effects on the glymphatic system.

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  20. Preoperative Diffusion-weighted Imaging to Reduce the Burden on Patients with Breast Cancer International journal

    Maya Honda, Mami Iima

    Radiology   Vol. 315 ( 3 ) page: e250964   2025.6

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  21. Time to Consider Diffusion Time: Exploring the Potential of Time-Dependent Diffusion MRI in Breast Cancer Imaging International journal Open Access

    Masako Kataoka, Mami Iima

    Radiology: Imaging Cancer   Vol. 7 ( 3 ) page: e250129   2025.5

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    DOI: 10.1148/rycan.250129

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  22. Advanced breast diffusion-weighted imaging: what are the next steps? A proposal from the EUSOBI International Breast Diffusion-weighted Imaging working group. International journal Open Access

    Maya Honda, Eric E Sigmund, Denis Le Bihan, Katja Pinker, Paola Clauser, Dimitrios Karampinos, Savannah C Partridge, Eva Fallenberg, Laura Martincich, Pascal Baltzer, Ritse M Mann, Julia Camps-Herrero, Mami Iima

    European radiology   Vol. 35 ( 4 ) page: 2130 - 2140   2025.4

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    OBJECTIVES: This study by the EUSOBI International Breast Diffusion-weighted Imaging (DWI) working group aimed to evaluate the current and future applications of advanced DWI in breast imaging. METHODS: A literature search and a comprehensive survey of EUSOBI members to explore the clinical use and potential of advanced DWI techniques and a literature search were involved. Advanced DWI approaches such as intravoxel incoherent motion (IVIM), diffusion kurtosis imaging (DKI), and diffusion tensor imaging (DTI) were assessed for their current status and challenges in clinical implementation. RESULTS: Although a literature search revealed an increasing number of publications and growing academic interest in advanced DWI, the survey revealed limited adoption of advanced DWI techniques among EUSOBI members, with 32% using IVIM models, 17% using non-Gaussian diffusion techniques for kurtosis analysis, and only 8% using DTI. A variety of DWI techniques are used, with IVIM being the most popular, but less than half use it, suggesting that the study identified a gap between the potential benefits of advanced DWI and its actual use in clinical practice. CONCLUSION: The findings highlight the need for further research, standardization and simplification to transition advanced DWI from a research tool to regular practice in breast imaging. The study concludes with guidelines and recommendations for future research directions and clinical implementation, emphasizing the importance of interdisciplinary collaboration in this field to improve breast cancer diagnosis and treatment. CLINICAL RELEVANCE STATEMENT: Advanced DWI in breast imaging, while currently in limited clinical use, offers promising improvements in diagnosis, staging, and treatment monitoring, highlighting the need for standardized protocols, accessible software, and collaborative approaches to promote its broader integration into routine clinical practice. KEY POINTS: Increasing number of publications on advanced DWI over the last decade indicates growing research interest. EUSOBI survey shows that advanced DWI is used primarily in research, not extensively in clinical practice. More research and standardization are needed to integrate advanced DWI into routine breast imaging practice.

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  23. Standardization and advancements efforts in breast diffusion-weighted imaging. Open Access

    Mami Iima, Maya Honda, Hiroko Satake, Masako Kataoka

    Japanese journal of radiology   Vol. 43 ( 3 ) page: 347 - 354   2025.3

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    Recent advancements in breast magnetic resonance imaging (MRI) have significantly enhanced breast cancer detection and characterization. Breast MRI offers superior sensitivity, particularly valuable for high-risk screening and assessing disease extent. Abbreviated protocols have emerged, providing efficient cancer detection while reducing scan time and cost. Diffusion-weighted imaging (DWI), a non-contrast technique, has shown promise in differentiating malignant from benign lesions. It offers shorter scanning times and eliminates contrast agent risks. Apparent diffusion coefficient (ADC) values provide quantitative measures for lesion characterization, potentially reducing unnecessary biopsies. Studies have revealed some correlations between ADC values and hormone receptor status in breast cancers, although substantial variability exists among studies. However, standardization remains challenging. Initiatives such as European Society of Breast Imaging (EUSOBI), Diffusion-Weighted Imaging Screening Trial (DWIST), Quantitative Imaging Biomarkers Alliance (QIBA) have proposed guidelines to ensure consistency in imaging protocols and equipment specifications, addressing variability in ADC measurements across different sites and vendors. Advanced techniques like Intravoxel incoherent motion (IVIM) and non-Gaussian DWI offer insights into tissue microvasculature and microstructure. Despite ongoing challenges, the integration of these advanced MRI techniques shows great promise for improving breast cancer diagnosis, characterization, and treatment planning. Continued research and standardization efforts are crucial for maximizing the potential of breast DWI in enhancing patient care and outcomes.

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  24. Retrospective BReast Intravoxel Incoherent Motion Multisite (BRIMM) multisoftware study International journal Open Access

    Dibash Basukala, Artem Mikheev, Xiaochun Li, Judith D. Goldberg, Nima Gilani, Linda Moy, Katja Pinker, Savannah C. Partridge, Debosmita Biswas, Masako Kataoka, Maya Honda, Mami Iima, Sunitha B. Thakur, Eric E. Sigmund

    Frontiers in Oncology   Vol. 15   page: 1524634 - 1524634   2025.2

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    Introduction

    The intravoxel incoherent motion (IVIM) model of diffusion weighted imaging (DWI) provides imaging biomarkers for breast tumor characterization. It has been extensively applied for both diagnostic and prognostic goals in breast cancer, with increasing evidence supporting its clinical relevance. However, variable performance exists in literature owing to the heterogeneity in datasets and quantification methods.

    Methods

    This work used retrospective anonymized breast MRI data (302 patients) from three sites employing three different software utilizing least-squares segmented algorithms and Bayesian fit to estimate 1<sub>st</sub> order radiomics of IVIM parameters perfusion fraction (f<sub>p</sub>), pseudo-diffusion (D<sub>p</sub>) and tissue diffusivity (D<sub>t</sub>). Pearson correlation (r) coefficients between software pairs were computed while logistic regression model was implemented to test malignancy detection and assess robustness of the IVIM metrics.

    Results

    D<sub>t</sub> and f<sub>p</sub> maps generated from different software showed consistency across platforms while D<sub>p</sub> maps were variable. The average correlation between the three software pairs at three different sites for 1<sub>st</sub> order radiomics of IVIM parameters were D<sub>t</sub>min/D<sub>t</sub>max/D<sub>t</sub>mean/D<sub>t</sub>variance/D<sub>t</sub>skew/D<sub>t</sub>kurt: 0.791/0.891/0.98/0.815/0.697/0.584; f<sub>p</sub>max/f<sub>p</sub>mean/f<sub>p</sub>variance/f<sub>p</sub>skew/f<sub>p</sub>kurt: 0.615/0.871/0.679/0.541/0.433; D<sub>p</sub>max/D<sub>p</sub>mean/D<sub>p</sub>variance/D<sub>p</sub>skew/D<sub>p</sub>kurt: 0.616/0.56/0.587/0.454/0.51. Correlation between least-squares algorithms were the highest. D<sub>t</sub>mean showed highest area under the ROC curve (AUC) with 0.85 and lowest coefficient of variation (CV) with 0.18% for benign and malignant differentiation using logistic regression. D<sub>t</sub> metrics were highly diagnostic as well as consistent along with f<sub>p</sub> metrics.

    Discussion

    Multiple 1<sub>st</sub> order radiomic features of D<sub>t</sub> and f<sub>p</sub> obtained from a heterogeneous multi-site breast lesion dataset showed strong software robustness and/or diagnostic utility, supporting their potential consideration in controlled prospective clinical trials.

    DOI: 10.3389/fonc.2025.1524634

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  25. Fat-signal suppression in breast diffusion-weighted imaging: the Good, the Bad, and the Ugly. International journal Open Access

    Denis Le Bihan, Mami Iima, Savannah C Partridge

    European radiology   Vol. 35 ( 2 ) page: 733 - 741   2025.2

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    OBJECTIVES: Fat-signal suppression is essential for breast diffusion magnetic resonance imaging (or diffusion-weighted MRI, DWI) as the very low diffusion coefficient of fat tends to decrease absolute diffusion coefficient (ADC) values. Among several methods, the STIR (short-tau inversion recovery) method is a popular approach, but signal suppression/attenuation is not specific to fat contrary to other methods such as SPAIR (spectral adiabatic (or attenuated) inversion recovery). This article focuses on those two techniques to illustrate the importance of appropriate fat suppression in breast DWI, briefly presenting the pros and cons of both approaches. METHODS AND RESULTS: We show here through simulation and data acquired in a dedicated breast DWI phantom made of vials with water and various concentrations of polyvinylpyrrolidone (PVP) how ADC values obtained with STIR DWI may be biased toward tissue components with the longest T1 values: ADC values obtained with STIR fat suppression may be over/underestimated depending on the T1 and ADC profile within tissues. This bias is also illustrated in two clinical examples. CONCLUSION: Fat-specific methods should be preferred over STIR for fat-signal suppression in breast DWI, such as SPAIR which also provides a higher sensitivity than STIR for lesion detection. One should remain aware, however, that efficient fat-signal suppression with SPAIR requires good B0 shimming to avoid ADC underestimation from residual fat contamination. CLINICAL RELEVANCE STATEMENT: The spectral adiabatic (or attenuated) inversion recovery (SPAIR) method should be preferred over short-tau inversion recovery (STIR) for fat suppression in breast DWI. KEY POINTS: Fat-signal suppression is essential for breast DWI; the SPAIR method is recommended. Short-tau inversion recovery (STIR) is not specific to fat; as a result, SNR is decreased and ADC values may be over- or underestimated. The STIR fat-suppression method must not be used after the injection of gadolinium-based contrast agents.

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  26. Deep Learning Applied to Diffusion-weighted Imaging for Differentiating Malignant from Benign Breast Tumors without Lesion Segmentation International journal

    Mami Iima, Ryosuke Mizuno, Masako Kataoka, Kazuki Tsuji, Toshiki Yamazaki, Akihiko Minami, Maya Honda, Keiho Imanishi, Masahiro Takada, Yuji Nakamoto

    Radiology: Artificial Intelligence   Vol. 7 ( 1 ) page: e240206   2025.1

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    Purpose To evaluate and compare the performance of different artificial intelligence (AI) models in differentiating between benign and malignant breast tumors at diffusion-weighted imaging (DWI), including comparison with radiologist assessments. Materials and Methods In this retrospective study, patients with breast lesions underwent 3-T breast MRI from May 2019 to March 2022. In addition to T1-weighted imaging, T2-weighted imaging, and contrast-enhanced imaging, DWI was performed with five b values (0, 200, 800, 1000, and 1500 sec/mm2). DWI data split into training and tuning and test sets were used for the development and assessment of AI models, including a small two-dimensional (2D) convolutional neural network (CNN), ResNet-18, EfficientNet-B0, and a three-dimensional (3D) CNN. Performance of the DWI-based models in differentiating between benign and malignant breast tumors was compared with that of radiologists assessing standard breast MR images, with diagnostic performance assessed using receiver operating characteristic analysis. The study also examined data augmentation effects (augmentation A: random elastic deformation, augmentation B: random affine transformation and random noise, and augmentation C: mixup) on model performance. Results A total of 334 breast lesions in 293 patients (mean age, 54.9 years ± 14.3 [SD]; all female) were analyzed. The 2D CNN models outperformed the 3D CNN on the test dataset (area under the receiver operating characteristic curve [AUC] with different data augmentation methods: range, 0.83-0.88 vs 0.75-0.76). There was no evidence of a difference in performance between the small 2D CNN with augmentations A and B (AUC: 0.88) and the radiologists (AUC: 0.86) on the test dataset (P = .64). When comparing the small 2D CNN to radiologists, there was no evidence of a difference in specificity (81.4% vs 72.1%, P = .64) or sensitivity (85.9% vs 98.8%, P = .64). Conclusion AI models, particularly a small 2D CNN, showed good performance in differentiating between malignant and benign breast tumors using DWI, without needing manual segmentation. Keywords: MR Imaging, Breast, Comparative Studies, Feature Detection, Diagnosis Supplemental material is available for this article. ©RSNA, 2024.

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  27. Comparing Lesion Conspicuity and ADC Reliability in High-resolution Diffusion-weighted Imaging of the Breast. Open Access

    Mami Iima, Rena Nakayama, Masako Kataoka, Martins Otikovs, Noam Nissan, Lucio Frydman, Yuta Urushibata, Maya Honda, Aika Okazawa, Hiroko Satake, Shinji Naganawa, Yuji Nakamoto

    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine   Vol. 24 ( 4 )   2025

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    PURPOSE: This study investigated the breast lesion conspicuity and apparent diffusion coefficient (ADC) reliability for three different diffusion-weighted imaging (DWI) protocols: spatiotemporal encoding (SPEN), single-shot echo-planar imaging (SS-EPI), and readout segmentation of long variable echo-trains (RESOLVE). METHODS: Sixty-five women suspected of having breast tumors were included in this study, with 44 lesions (36 malignant, 8 benign) analyzed further. Breast MRI was performed on a 3 Tesla (3T) system (MAGNETOM Prisma, Siemens) equipped with a dedicated 18-channel breast array coil for a phantom and patients. Three DWI protocols-SPEN, SS-EPI, and RESOLVE-were used. SS-EPI was acquired with an in-plane resolution of 2 × 2 mm2, a slice thickness of 3 mm, and b-values of 0 and 1000 s/mm2. SPEN had a higher in-plane resolution of 1 × 1 mm2, a slice thickness of 1.5 mm, and b-values of 0, 850, and 1500 s/mm2. RESOLVE was acquired with an in-plane resolution of 1 × 1 mm2, a slice thickness of 1.5 mm, and b-values of 0 and 850 s/mm2. Lesion conspicuity and ADC values were evaluated. RESULTS: The average lesion conspicuity scores were significantly higher for RESOLVE (3.54 ± 0.65) than for SPEN (3.07 ± 0.91) or SS-EPI (2.48 ± 0.78) (P < 0.01). The SPEN score was significantly higher than the SS-EPI score (P < 0.01). Phantom measurements indicated marginally lower ADC values for SPEN compared to SS-EPI and RESOLVE across all concentrations. The results revealed that SPEN (b = 0, 850, 1500 sec/mm2) yielded significantly lower ADC values compared to SPEN (b = 0, 850 sec/mm2) in malignant lesions (P < 0.01), with no significant difference observed between SPEN (b = 0, 850 sec/mm2), SS-EPI, and RESOLVE. For benign lesions, no significant difference in ADC values was found between SPEN (b = 0, 850 sec/mm2), SPEN (b = 0, 850, 1500 sec/mm2), SS-EPI, and RESOLVE. CONCLUSION: RESOLVE provided the highest lesion conspicuity, and ADC values in breast lesions were not significantly different among sequences ranging b values 850-1000 sec/mm2. SPEN with higher b-values (0, 850, 1500 vs. 0, 850 sec/mm2) yielded significantly lower ADC values in malignant lesions, highlighting the importance of b-value selection in ADC quantification.

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  28. Institutional Variability in Ultrafast Breast MR Imaging: Comparing Compressed Sensing and View Sharing Techniques with Different Patient Populations and Contrast Injection Protocols Open Access

    Honda Maya, Kataoka Masako, Iima Mami, Ota Rie, Okazawa Aika, Fukushima Yasuhiro, Nickel Marcel Dominik, Sato Fumiaki, Masuda Norikazu, Okada Tsutomu, Nakamoto Yuji

    Magnetic Resonance in Medical Sciences   Vol. 24 ( 4 ) page: n/a   2025

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    <p>Purpose: To assess the institutional variability in ultrafast dynamic contrast-enhanced (UF-DCE) breast MRI using time-resolved angiography with stochastic trajectories (TWIST)-volumetric interpolated breath-hold examination (VIBE) and compressed sensing (CS)-VIBE sequences acquired at 2 different institutions with different patient populations and contrast injection protocols.</p><p>Methods: UF-DCE MR images of 18 patients from site A acquired using a TWIST-VIBE sequence, and UF-DCE MR images of 18 patients from site B acquired with a CS-VIBE sequence, were retrospectively evaluated and compared. The 2-site patient cohort was matched for patient age, background parenchymal enhancement, malignancy or benignity, and lesion size. Qualitative assessments included noise, blurring, poor fat suppression, aliasing artifact, motion artifact, lesion conspicuity, lesion morphology, time-intensity-curve smoothness, and vessel delineation. For quantitative assessment, the bolus arrival time was evaluated for each lesion, and its diagnostic performance in discriminating between benign and malignant lesions was examined using receiver operating characteristics analysis.</p><p>Results: Thirteen malignant and five benign lesions were included from each site. Qualitative evaluation revealed that poor fat suppression and aliasing artifacts were visible in images from site A with TWIST-VIBE (<i>P</i> = 0.004 and <i>P</i> < 0.001), whereas motion artifacts were present in images from site B with CS-VIBE (<i>P</i> = 0.04). Lesion morphology assessments (<i>P </i>< 0.001) and vessel delineation (<i>P</i> < 0.001) were superior for images from site B with CS-VIBE. Bolus arrival time was significantly longer with TWIST-VIBE than with CS-VIBE, for both benign and malignant lesions (<i>P</i> < 0.001). The area under the receiver operating characteristics curve was 0.55 for site A and 0.69 for site B (<i>P</i> = 0.39).</p><p>Conclusion: Both acquisitions allowed evaluation of breast lesions with good lesion conspicuity and time-intensity-curve smoothness, whereas CS-VIBE was superior to TWIST-VIBE for morphological evaluation of breast lesions and depiction of blood vessels in the breast. Injection rate appears to have a significant impact on semi-quantitative parameters derived from UF-DCE MRI.</p>

    DOI: 10.2463/mrms.mp.2024-0152

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  29. Quantitative MR Imaging of the Breast Open Access

    Kataoka Masako, Honda Maya, Iima Mami, Ueguchi Takashi, Matsuda Megumi, Aoki Takatoshi, Ko Eun Sook

    Magnetic Resonance in Medical Sciences   Vol. 24 ( 3 ) page: n/a - 429   2025

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    <p>Breast MRI has become essential for diagnosing and managing breast diseases. MRI interpretation has traditionally relied on subjective assessment according to Breast Imaging-Reporting and Data System, but recent advances emphasize the value of quantitative MRI data as objective imaging biomarkers. Techniques such as dynamic contrast-enhanced MRI (DCE-MRI), including ultrafast DCE-MRI and diffusion-weighted imaging are the most established for quantitative analysis, yet their routine application is limited by a lack of standardization in imaging protocols. Recent efforts focus on improving reproducibility, with studies showing that significant changes in the apparent diffusion coefficient can reliably indicate biological alterations in breast lesions. Emerging quantitative MRI approaches including synthetic MRI and fat imaging show promise in lesion characterization and treatment response assessment but require further validation and harmonization before widespread clinical use. For methodological aspect, radiomics has demonstrated strong diagnostic and predictive capabilities in breast MRI research. Quantitative approach for background parenchymal enhancement indicated its association with future breast cancer incidence or recurrence. Continued efforts to standardize and validate quantitative MRI parameters are crucial to fully integrating these tools into routine breast imaging practice.</p>

    DOI: 10.2463/mrms.rev.2025-0085

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  30. 40 years of diffusion MRI: a journey from basic science to clinical breakthrough Open Access

    Mami Iima, Yukio Miki, Shinji Naganawa

    Japanese Journal of Radiology   Vol. 42 ( 12 ) page: 1355 - 1356   2024.12

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    DOI: 10.1007/s11604-024-01669-2

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  31. Sequential Reading Effects in Digital Breast Tomosynthesis: Improving False-Positive Rates Without Compromising Cancer Detection International journal

    Mami Iima, Hiroko Satake

    Radiology   Vol. 313 ( 2 ) page: e242642   2024.11

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  32. The Clinical Usefulness of DWI Using Spatiotemporal Encoding (SPEN) : Results of Observer Study Depending on the Experience [Presidential Award Proceedings]

    NAKAYAMA Rena, IIMA Mami, KATAOKA Masako, HONDA Maya, OTIKOVS Martins, NISSAN Noam, FRYDMAN Lucio, URUSHIBATA Yuta, OKAZAWA Aika, TSUJI Kazuki, TOI Masakazu, NAKAMOTO Yuji

    Japanese Journal of Magnetic Resonance in Medicine   Vol. 44 ( 3 ) page: 85 - 88   2024.8

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    <p> Three DW protocols (SPEN, SS-EPI, RESOLVE) were evaluated by breast radiologists and medical students using a semi-quantitative scoring system. Additionally, a breast-specific phantom, encompassing typical malignant and benign breast lesions, was used to measure the ADC values in each DWI protocol. The ADC values were also measured for malignant lesions. SPEN sequences demonstrated significantly higher conspicuity scores than conventional DWI. Moreover, RESOLVE exhibited significantly higher scores compared to both SPEN and conventional DWI.</p>

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  33. Spatiotemporal encoding(SPEN)によるDWIの臨床的有用性 経験度に基づく解析結果について [大会長賞記録]

    中山 怜那, 飯間 麻美, 片岡 正子, 本田 茉也, Martins Otikovs, Noam Nissan, Lucio Frydman, 漆畑 勇太, 岡澤 藍夏, 辻 和貴, 戸井 雅和, 中本 裕士

    日本磁気共鳴医学会雑誌   Vol. 44 ( 3 ) page: 85 - 88   2024.8

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  34. Diffusion-Weighted MRI for the Assessment of Molecular Prognostic Biomarkers in Breast Cancer. International journal Open Access

    Mami Iima, Masako Kataoka, Maya Honda, Denis Le Bihan

    Korean journal of radiology   Vol. 25 ( 7 ) page: 623 - 633   2024.7

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    This study systematically reviewed the role of diffusion-weighted imaging (DWI) in the assessment of molecular prognostic biomarkers in breast cancer, focusing on the correlation of apparent diffusion coefficient (ADC) with hormone receptor status and prognostic biomarkers. Our meta-analysis includes data from 52 studies examining ADC values in relation to estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), and Ki-67 status. The results indicated significant differences in ADC values among different receptor statuses, with ER-positive, PgR-positive, HER2-negative, and Ki-67-positive tumors having lower ADC values compared to their negative counterparts. This study also highlights the potential of advanced DWI techniques such as intravoxel incoherent motion and non-Gaussian DWI to provide additional insights beyond ADC. Despite these promising findings, the high heterogeneity among the studies underscores the need for standardized DWI protocols to improve their clinical utility in breast cancer management.

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  35. 乳癌免疫療法のリアルワールドでの問題点、そして今後の展望 Triple Negative乳癌に対するPembrolizumab併用術前化学療法のMRI評価 早期治療効果予測の可能性

    片岡 正子, 岡澤 藍夏, 川島 雅央, 川口 展子, 河口 浩介, 本田 茉也, 太田 理恵, 飯間 麻美, 山田 洋介, 竹内 康英, 三宅 可奈江, 山口 絢音, 高田 正泰, 中本 裕士

    日本乳癌学会総会プログラム抄録集   Vol. 32回   page: 9 - 9   2024.7

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  36. 乳癌免疫療法のリアルワールドでの問題点、そして今後の展望 Triple Negative乳癌に対するPembrolizumab併用術前化学療法のMRI評価 早期治療効果予測の可能性

    片岡 正子, 岡澤 藍夏, 川島 雅央, 川口 展子, 河口 浩介, 本田 茉也, 太田 理恵, 飯間 麻美, 山田 洋介, 竹内 康英, 三宅 可奈江, 山口 絢音, 高田 正泰, 中本 裕士

    日本乳癌学会総会プログラム抄録集   Vol. 32回   page: 9 - 9   2024.7

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    Language:Japanese   Publisher:(一社)日本乳癌学会  

  37. In Vivo and Post-mortem Comparisons of IVIM/Time-dependent Diffusion MR Imaging Parameters in Melanoma and Breast Cancer Xenograft Models.

    Yuko Someya, Mami Iima, Hirohiko Imai, Hiroyoshi Isoda, Tsuyoshi Ohno, Masako Kataoka, Denis Le Bihan, Yuji Nakamoto

    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine   Vol. 24 ( 4 )   2024.5

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    PURPOSE: We aimed to investigate the changes in intravoxel incoherent motion (IVIM) and diffusion parameters between in vivo and post-mortem conditions and the time dependency of these parameters using two different mouse tumor models with different vessel lumen sizes. METHODS: Six B16 and six MDA-MB-231 xenograft mice were scanned using 7 Tesla MRI under both in vivo/post-mortem conditions. Diffusion weighted imaging with 17 b-values (0-3000 s/mm2) were obtained at two diffusion times (9 and 27.6 ms). The shifted apparent diffusion coefficient (sADC) using 2 b-values (200 and 1500 s/mm2), non-Gaussian diffusion and IVIM parameters (ADC0, K, fIVIM) were estimated at each of the diffusion times. The results were evaluated by repeated measures two-way analysis of variance and post hoc Bonferroni test. RESULTS: In B16 tumors, fIVIM significantly decreased with post-mortem conditions (from 12.6 ± 6.5% to 5.2 ± 1.9%, P < 0.05 at long diffusion time; from 11.0 ± 2.4% to 4.6 ± 2.7%, P < 0.05 at short diffusion time). In MDA-MB-231 tumors, fIVIM also significantly decreased (from 8.8 ± 3.8% to 2.6 ± 1.1%, P < 0.05 at long; from 7.9 ± 5.4% to 2.9 ± 1.1%, P < 0.05 at short). No diffusion time dependency was observed (P = 0.59 in B16 and P = 0.77 in MDA-MB-231). The sADC and ADC0 values tended to decrease and the K value tended to increase after sacrificing and when increasing the diffusion time. CONCLUSION: The fIVIM values dropped after sacrificing, confirming that IVIM MRI is a promising quantitative parameter to evaluate blood microcirculation. The presence of residual post-mortem fIVIM values suggested that the influence of water molecule diffusion in the blood lumen may contribute to the IVIM effect. Diffusion MRI parameter's time dependency and those changes after sacrificing could possibly provide additional insights into diffusion hindrance mechanisms.

    DOI: 10.2463/mrms.mp.2023-0078

    PubMed

  38. Potential of the Diffusion-based Noncontrast Protocol for Breast Imaging: Current Status and Hints for Improvements. International journal

    Masako Kataoka, Mami Iima

    Radiology   Vol. 311 ( 2 ) page: e241058   2024.5

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    DOI: 10.1148/radiol.241058

    Web of Science

    Scopus

    PubMed

  39. Comments on “A Channel‐Dimensional Feature‐Reconstructed Deep Learning Model for Predicting Breast Cancer Molecular Subtypes on Overall b‐Value Diffusion‐Weighted MRI” International journal

    Akihiko Minami, Ryosuke Mizuno, Masako Kataoka, Mami Iima

    Journal of Magnetic Resonance Imaging     2024.2

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    DOI: 10.1002/jmri.29311

    PubMed

  40. It Is Time to Use Apparent Diffusion Coefficient in Breast MRI Diagnostics. International journal

    Maya Honda, Mami Iima

    Radiology   Vol. 310 ( 2 ) page: e240125   2024.2

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    DOI: 10.1148/radiol.240125

    PubMed

  41. Utility of Diffusion-weighted MR Imaging for Evaluating the Depth of Invasion in Oral Tongue Squamous Cell Carcinoma

    Hiroki Tanaka, Sho Koyasu, Masahiro Kikuchi, Mami Iima, Koichi Omori, Yuji Nakamoto

    Magnetic Resonance in Medical Sciences     2024

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    PURPOSE: The 8th edition of the American Joint Committee on Cancer staging system included the depth of invasion (DOI) for the T classification of oral cancer. However, no standardized method has been established to clinically measure the DOI. This study aimed to investigate the accuracy of MRI-based DOI for oral tongue squamous cell carcinoma (OTSCC) in each MRI sequence. METHODS: We enrolled 49 patients with histologically proven OTSCC, treated surgically between April 2017 and February 2021. We divided the DOI into three groups using 5 and 10 mm, the thresholds for determining the T stage, and retrospectively evaluated the agreement between MRI-based DOI and pathological DOI (pDOI) for each MRI sequence, axial T1-weighted imaging (T1WI), T2-weighted imaging with fat suppression (FS-T2WI), contrast-enhanced T1WI with fat suppression (CE-T1WI), diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) maps. We also divided the DOI into two groups using 3 mm, the threshold for considering elective neck dissection, and evaluated the overestimation rate of MRI-based DOI in lesions with pDOI ≤ 3 mm. RESULTS: With 5-mm and 10-mm divisions, the accuracy of the DOI assessment was highest on DWI (0.82, weighted kappa = 0.85). With a 3-mm division, the accuracy was also highest on DWI (0.87, kappa = 0.73). The overestimation rate of the MRI-based DOI in lesions with pDOI ≤ 3 mm was lowest on DWI (27.8%). CONCLUSION: DOI on DWI exhibits a comparatively higher rate of concordance with pDOI. DWI may be more useful than other MRI sequences in evaluating the DOI of OTSCC.

    DOI: 10.2463/mrms.mp.2023-0137

    PubMed

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Books 3

  1. 医療機器プログラム(SaMD)-その規制と市場参入の課題-

    桐山 瑶子, 浅原 弘明、飯間 麻美、伊藤 寛子、硴﨑 裕晃、川口 浩和、桐山 皓行、坂本 伸太郎、鈴木 孝司、野村 章洋、深谷 李映、藤原 崇志、三澤 佐知子、山岸 慧

    薬事日報社  2025.9  ( ISBN:4840816603

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    Total pages:280  

    ASIN

  2. InnerVision, August 2025 Issue

    Mami Iima( Role: Contributor)

    2025.7 

  3. インナービジョン 39巻 9号 MRI研究の最新動向と臨床応用

    Mami Iima, Satoko Ishigaki, Hiroko Satake( Role: Contributor)

    2024.10 

MISC 5

  1. Assessment of breast tumors with magnetic resonance imaging through perfusion: DCE MRI and Ultrafast MRI

    片岡正子, 本田茉也, 西本あずさ, 岡澤藍夏, 大橋茜, 阪口怜奈, 太田理恵, 飯間麻美, 中本裕士

    超音波医学 Supplement   Vol. 52   2025

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  2. 卵巣癌間質の腫瘍関連線維症(Tumor-associated fibrosis)と拡散強調MRIの可能性

    藤本裕基, 吉原雅人, 宮本絵美里, 山北由彦, 伊吉祥平, 宇野枢, 茂木一将, 北見和久, 飯間麻美, 梶山広明

    Abstracts. Annual Symposium. Japanese Society for the Advancement of Women’s Imaging (CD-ROM)   Vol. 25th   2024

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  3. Step up MRI2024 最前線を行く:MRI研究の最新動向と臨床応用 III 各領域における最新MRI技術の臨床応用 5.乳腺MRI:最先端のイメージング技術

    飯間麻美, 石垣聡子, 佐竹弘子

    Innervision   Vol. 39 ( 9 )   2024

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  4. The Clinical Usefulness of DWI Using Spatiotemporal Encoding (SPEN) : Results of Observer Study Depending on the Experience [Presidential Award Proceedings]

    中山怜那, 飯間麻美, 飯間麻美, 片岡正子, 本田茉也, OTIKOVS Martins, NISSAN Noam, FRYDMAN Lucio, 漆畑勇太, 岡澤藍夏, 辻和貴, 戸井雅和, 戸井雅和, 中本裕士

    日本磁気共鳴医学会雑誌(Web)   Vol. 44 ( 3 )   2024

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  5. HER2低発現乳癌の画像所見

    本田茉也, 本田茉也, 本田茉也, 片岡正子, 佐藤史顕, 谷田梨乃, 飯間麻美, 太田理恵, 續木定智, 岡田務

    日本乳癌学会学術総会(CD-ROM)   Vol. 32nd   2024

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Presentations 76

  1. A MULTI-CENTER STUDY EVALUATING THE IMPACT OF FAT SUPPRESSION AND B-VALUES ON BREAST LESION VISIBILITY AND ADC VALUES IN DWI

    Erika Inoue, Mami Iima, Masako Y. Kataoka, Ken Yamaguchi, Yukiko Tokuda, Akane Ohashi, Hiroko Satake, Takashi Ueguchi, Kazushige Ichikawa, Yutaka Kato, Yoshihiro Koyama, Yuto Kumano, Reika Sawaya, Maya Honda, Kazunori Kubota, Tomoyuki Fujioka, Kazunori Oohashi, Sachiko Yamada, Denis Le Bihan, Takayoshi Ishimori, Shinji Naganawa, Yuji Nakamoto

    2025.11.30 

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    Event date: 2025.11 - 2025.12

  2. 乳房MRI読影アップデート:Ultrafast MRIとDWIの疑問を解決する Invited

    飯間麻美

    広島画像診断講演会  2025.10.10 

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    Event date: 2025.10

    Language:Japanese   Presentation type:Public lecture, seminar, tutorial, course, or other speech  

  3. Multiparametric Approach Using Breast MRI in the Era of Breast Cancer Treatment Invited

    Mami Iima

    Korean Congress of Radiology 2025  2025.9.25 

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    Event date: 2025.9

    Presentation type:Oral presentation (invited, special)  

  4. Quality Assurance, Standardization & Benchmarking in Breast MRI : Panel Discussion on Sustainability

    Mami Iima, M.D., Ph.D., Bonnie Joe, M.D., Ph.D., Elizabeth Morris, M.D., F.A.C.R., Linda Moy, M.

    ISMRM Workshop on Breast MRI: Technological Advances & Clinical Applications  2025.9.14 

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    Event date: 2025.9

  5. Automated Breast Cancer Detection and Classification Using Machine Learning on DWI

    Kaito Nonoyama, Mami Iima, Ryosuke Mizuno, Keiho Imanishi, Hiroko Satake, Rintaro Ito, Masako Kataoka, Shinji Naganawa

    ISMRM JPC 2025 The 10th Annual Scientific Meeting of the ISMRM Japanese Chapter  2025.8.30 

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    Event date: 2025.8

  6. Small Animal Imaging: Translational Perspectives

    Mami Iima

    ISMRM JPC 2025 The 10th Annual Scientific Meeting of the ISMRM Japanese Chapter  2025.8.30 

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    Event date: 2025.8

  7. Comparison of 3D Diagonal and 3-Scan Trace Diffusion-Weighted Imaging for Breast MRI

    Yusuke Jo, Mami Iima, Hiroko Satake, Yunhao Zhang, Yutaka Kato, Yuki Sato, Satoko Ishigaki, Ryota Hyodo, Yoshito Ichiba, Shinji Naganawa

    ISMRM JPC 2025 The 10th Annual Scientific Meeting of the ISMRM Japanese Chapter  2025.8.30 

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    Event date: 2025.8

  8. 乳腺MREにおける最適な加振アプローチの検討

    中島 憲一, 飯間 麻美, 兵藤 良太, 清水 みく, 真野 愛輝, 佐竹 弘子, 常 裕輔, 加藤 裕, 大河内 慶行, 上田 優, 宇治 誠人, 杢野 泰司, Denis Le Bihan, 長縄 慎二

    第53回 日本磁気共鳴医学会大会  2025.8.31 

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    Event date: 2025.8

    Presentation type:Poster presentation  

  9. Japanese success at ISMRM 2025

    The 53rd Annual Meeting of the Japanese Society for Magnetic Resonance in Medicine  2025.8.31 

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    Event date: 2025.8

  10. Comparative Evaluation of Trace DWI and Diagonal DWI in Phantom Experiments and Clinical Studies

    Yuki Sato, Mami Iima, Hiroko Satake, Yusuke Jo, Yunhao Zhang, Yutaka Kato, Kazushige Ichikawa, Ryota Hyodo, Yoshito Ichiba, Hiroshi Imai, Shinji Naganawa

    The 53rd Annual Meeting of the Japanese Society for Magnetic Resonance in Medicine  2025.8.31 

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    Event date: 2025.8

  11. Automatic detection and diagnosis of breast cancer by AI using diffusionweighted images

    The 53rd Annual Meeting of the Japanese Society for Magnetic Resonance in Medicine  2025.8.31 

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    Event date: 2025.8

  12. Clinical Application of Latest Technologies in Breast MRI: From AI Image Reconstruction to Ultrafast Dynamic Imaging

    Mami Iima

    The 53rd Annual Meeting of the Japanese Society for Magnetic Resonance in Medicine  2025.8.30 

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    Event date: 2025.8

  13. Association between washout pattern in Time Intensity Curve of ultra-early phase and pathological features of breast cancer in breast MRI

    Yusuke Jo, Mami Iima, Hiroko Satake, Kosuke Nanataki, Yutaka Kato, Satoko Ishigaki, Rintaro Ito, Ryota Hyodo, Aki Mano, Hiroshi Imai, Yoshihito Ichiba, Dominik Nickel, Shinji Naganawa

    The 53rd Annual Meeting of the Japanese Society for Magnetic Resonance in Medicine  2025.8.31 

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    Event date: 2025.8

  14. Development of an ADC quantification methodology robust to differences in phantom temperature toward breast DWI standardization

    Takashi Ueguchi, Tomoki Haji, Sachiko Yamada, Yuto Kumano, Yukiko Tokuda, Ken Yamaguchi, Kiyoshi Dogomori, Yutaka Kato, Kazushige Ichikawa, Hiroko Satake, Kazunori Kubota, Tomoyuki Fujioka, Kazunori Ohashi, Masako Kataoka, Reika Sawaya, Yoshihiro Koyama, Mami Iima

    The 53rd Annual Meeting of the Japanese Society for Magnetic Resonance in Medicine  2025.8.29 

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    Event date: 2025.8

  15. 高分解能DWIによる乳癌のpCR予測能,サブタイプ別検討

    岡澤 藍夏, 片岡 正子, 本田 茉也, 西本 あずさ, 竹内 康英, 飯間 麻美, 太田 理恵, 中本 裕士

    2025.8.31 

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    Event date: 2025.8

    Presentation type:Poster presentation  

  16. Pectoral Muscle Invasion on Preoperative MRI for Breast Malignancies: A Retrospective Study with Non-contrast T1WI and Fat-suppressed CE T1WI

    Azusa Nishimoto, Masako Kataoka, Maya Honda, Aika Okazawa, Yasuhide Takeuchi, Mami Iima, Rie Ota, Norikazu Masuda, Yuji Nakamoto

    The 53rd Annual Meeting of the Japanese Society for Magnetic Resonance in Medicine  2025.8.29 

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    Event date: 2025.8

  17. 肝細胞癌を合併したβ-catenin活性化型肝細胞腺腫の1例

    伊藤 大智, 兵藤 良太, 栗本 景介, 水野 隆史, 佐藤 啓, 佐々木 素子, 石津 洋二, 飯間 麻美, 長縄 慎二

    第38回日本腹部放射線学会 

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    Event date: 2025.6

    Presentation type:Poster presentation  

  18. Diagonal DWI: A Time-efficient Alternative to 3-scan Trace DWI for Breast Lesion Evaluation at 3.0T - Phantom Study and Clinical Assessment

    Yusuke Jo, Mami Iima, Yutaka Kato, Yunhao Zhang, Hiroko Satake, Yuki Sato, Kazushige Ichikawa, Satoko Ishigaki, Ryota Hyodo, Yoshito Ichib, Shinji Naganawa

    ISMRM 2025  2025.5 

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    Event date: 2025.5

    Language:English  

  19. Multi-Center Optimization of Breast DWI: Comparative Analysis of Fat Suppression Methods (STIR vs. SPAIR) and B-values (800 vs.1500 s/mm2 )

    Erika Inoue, Mami Iima, Yukiko Tokuda, Masako Kataoka, Ken Yamaguchi, Akane Ohashi, Takashi Ueguchi, Hiroko Satake, Kazushige Ichikawa, Yutaka Kato, Yoshihiro Koyama, Yuto Kumano, Sachiko Yamada, Reika Sawaya, Maya Honda, Kazunori Kubota, Kazunori Ohashi, Tomoyuki Fujioka, Takayoshi Ishimori, Shinji Naganawa, Yuji Nakamoto

    ISMRM 2025  2025.5 

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    Event date: 2025.5

    Language:English  

  20. Machine Learning-Based Automating Breast Cancer Detection and Classification using DWI

    Mami Iima, Ryosuke Mizuno, Masako Kataoka, Akihiko Minami, Maya Honda, Keiho Imanishi, Yunhao Zhang, Hiroko Satake, Rintaro Ito, Shinji Naganawa, Yuji Nakamoto

    ISMRM 2025  2025.5 

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    Event date: 2025.5

    Language:English  

  21. Time-Dependent Diffusion MRI Parameters for Non-invasive Assessment of PARVA Expression in Breast Cancer

    Mami Iima, Hirohiko Imai, Marino Akamatsu, Minsoo Kim, Noriko Gotoh, Yasuto Takeuchi, Tomomi Nobashi, Masako Kataoka, Akito Otani, Maya Honda, Denis LeBihan, Hiroko Satake, Shinji Naganawa, Yuji Nakamoto

    ISMRM 2025  2025.5 

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    Event date: 2025.5

    Language:English  

  22. Phantom imaging protocol for breast DWI standardization: Influence of phase encoding direction on ADC measurement

    Sachiko Yamada, Tomoki Haji, Yuto Kumano, Reika Sawaya, Yoshihiro Koyama, Mami Iima, Takashi Ueguchi

    The 84th Annual Meeting of the Japan Radiological Society  2025.4 

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    Event date: 2025.4

    Language:English  

  23. Effect of B-value and Fat Suppression on Lesion Conspicuity and ADC Value in Breast DWI

    Erika Inoue, Mami Iima, Masako Kataoka, Akane Ohashi, Ishimori Takayoshi, Ken Yamaguchi, Yukiko Tokud, Maya Hond, Sachiko Takahar, Yuji Nakamo

    The 84th Annual Meeting of the Japan Radiological Society  2025.4 

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    Event date: 2025.4

    Language:English  

  24. Volumetry using high-resolution (HR) DWI for evaluating neoadjuvant systemic treatment

    Aika Okazawa, Masako Kataoka, Maya Honda, Azusa Nishimoto, Rie Ota, Yasuhide Takeuchi, Mami Iima, Yuji Nakamoto

    The 84th Annual Meeting of the Japan Radiological Society  2025.4 

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    Event date: 2025.4

    Language:English  

  25. Quality control of ADC measurements with phantoms: A robust methodology for temperature variations in reproducibility analysis

    Takashi Ueguchi, Tomoki Haji, Mami Iima, Yuto Kumano, Reika Sawaya, Sachiko Yamada, Yoshihiro Koyama

    The 84th Annual Meeting of the Japan Radiological Society  2025.4 

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    Event date: 2025.4

    Language:English  

  26. 拡散MRIによる腫瘍イメージングの新展開

    飯間 麻美

    分子研研究会/スピン生命異分野研究会  2025.2.27 

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    Event date: 2025.2

    Language:Japanese  

  27. Assessment of PARVA and ILK Expression in Breast Cancer: A Time-dependent Diffusion MRI Approach

    Ayu Shirakashi, Midori Takeda, Keisuke Kitahata, Minsoo KIM, Tomi Nobashi, Masako Kataoka, Marino Akamatsu, Mami Iima

    ISMRM Workshop on 40 years of Diffusion: Past, Present & Future Perspectives  2025.2 

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    Event date: 2025.2

    Language:English  

  28. Effect of B Values and Choice of Fat Suppression Method on Lesion Evaluation in Breast DWI

    Erika INOUE, Mami IIMA, Masako KATAOKA, Akane OHASHI, Maya HONDA, Ken YAMAGUCHI, Yukiko TOKUDA, Sachiko TAKAHARA, Takayoshi ISHIMORI, Yuji NAKAMOTO

    ISMRM Workshop on 40 years of Diffusion: Past, Present & Future Perspectives  2025.2 

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    Event date: 2025.2

    Language:English  

  29. Deep Learning for Automated Breast Tumor Detection and Classification in Diffusion-Weighted MRI

    Yunhao Zhang, Ryosuke Mizuno, Masako Kataoka, Akihiko Minami, Maya Honda, Keiho Imanishi, Hiroko Satake, Yusuke Jo, Rintaro Ito, Shinji Naganawa, Yuji Nakamoto, Mami Iim

    ISMRM Workshop on 40 years of Diffusion: Past, Present & Future Perspectives  2025.2 

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    Event date: 2025.2

    Language:English  

  30. Diagonal versus Three-directional Trace Diffusion-weighted Imaging for 3T Breast MRI:Phantom and Clinical Study

    Yusuke Jo, Mami Iima, Yutaka Kato, Yunhao Zhang, Hiroko Satake, Yuki Sato, Kazushige Ichikawa, Satoko Ishigaki, Ryota Hyodo, Yoshito Ichiba, Shinji Naganawa

    ISMRM Workshop on 40 years of Diffusion: Past, Present & Future Perspectives  2025.2.18 

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    Event date: 2025.2

    Language:English   Presentation type:Poster presentation  

  31. Case of the Day Breast Imaging Invited

    Yusuke Jo MD, Mami Iima MD, PhD., Hiroko Satake MD, PhD., Shinji Naganawa, MD, PhD.

    RSNA Scientific Assembly and Annual Meeting  2024.12.2 

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    Event date: 2024.11 - 2024.12

  32. 乳房MRIおよび拡散強調画像における進歩と標準化の取り組み (シンポジウム 乳癌を早期診断する) Invited

    飯間麻美

    第83回日本医学放射線学会学術総会  2024.4.13 

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    Event date: 2024.4

  33. Retrospective Deep Neural Network Analysis of Intravoxel Incoherent Motion Breast Tumor MRI

    Dibash Basukala, Artem Mikhee, Nima Gilani, Linda Moy, Katja Pinker, Mami Iima, Oliver J. Gurney-Champion, Sunitha B. Thakur, Eric E. Sigmund

    ISMRM Workshop on Moving Forward with Intravoxel Incoherent Motion Modeling for Diffusion-Weighted MRI An Attempt at Consensus  2024.3.26 

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    Event date: 2024.3

  34. いろんな目で乳がんをみる

    片岡, 正子, 飯間, 麻美, 三宅, 可奈江, 松本, 純明, 本田, 茉也, 岡澤, 藍夏, 橋本, 陽菜

    京都大学アカデミックデイ2022〜創立125周年記念〜  2022.6.19 

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    Event date: 2022.6

  35. Conventional Breast MRI Techniques & Reporting. No Way to Treat a Lady: Breast & Female Reproductive Organ Cancers. Invited

    ISMRM;SMRT Virtual Conference;Exhibition  2020.8.8 

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    Event date: 2020.8

  36. Read-out segmented echo-planar imaging diffusion weighted imaging for evaluating head and neck region

    Sho Koyasu, Mami Iima, Shigeaki Umeoka, Denis Le Bihan, David A. Porter, Kaori Togashi

    ISMRM 2014, Milan, Italy  2014.5.10 

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    Event date: 2014.5

  37. High-resolution 3D MR imaging of the sellar and parasellar space using SPACE at 3.0 T

    Emiko Morimoto, Mitsunori Kanagaki, Akira Yamamoto, Tomohisa Okada, Seiko Kasahara, Satoshi Nakajima, Mami Iima, Ryo Sakamoto, Kaori Togashi

    19th Annual Meeting & Exhibition, ISMRM (Montreal, Canada)  2011.5.11 

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    Event date: 2011.5

  38. The value of DWI score in predicting Disease-Free Survival for Breast Cancer Patients who underwent Neoadjuvant Systemic Treatment

    Rie Ota, Masako Kataoka, Mami Iima, Maya Honda, Aika Okazawa, Yosuke Yamada, Yasuhide Takeuchi, Masahiro Takada, Takeshi Kubo, Yuji Nakamo

    Diffusion Study Group Trainee Day: 24 Hours of DIFFUSION Around the World!  2024.2.2 

  39. The value of DWI based parameters at interim MRI for the early prediction of residual tumor after neoadjuvant systemic therapy

    Aika Okazawa, Masako Kataoka, Mami Iima Rie, Ota, Maya Honda, Akane Ohashi Yuji Nakamoto

    Diffusion Study Group Trainee Day: 24 Hours of DIFFUSION Around the World!  2024.2.2 

  40. The Optimal Timepoint for Lesion depiction in Ultrafast DCE MRI: Correlation with lesion size and Invasive Breast Cancer Subtype

    Masako Y Kataoka, Rena Sakaguchi, Maya Honda, Mami Iima, Masahiro Y Takada, Kumiko Ando, Yuji Y Nakamoto

    2024 ISMRM & ISMRT Annual Meeting & Exhibition  2024.5.9 

  41. Prediction of pCR after neoadjuvant chemotherapy using parameters from Interim MRI for Triple Negative and HER-2 positive invasive breast cancer

    Masako Kataoka, Aika Okazawa, Rie Ota, Maya Honda, Akane Ohashi, Mami Iima, Yosuke Yamada, Yasuhide Takeuchi, Masahiro Takada, Yuji Nakamoto

    The 11th Takeda Science Foundation Symposium on PharmaSciences  2024.1.26 

  42. Predicting Disease-Free Survival by DWI and DCE MRI Scores for Breast Cancer Patients with Neoadjuvant Systemic Treatment

    Rie Ota, Masako Kataoka, Mami Iima, Maya Honda, Aika Okazawa, Yasuhide Takeuchi, Yosuke Yamada, Masahiro Takada, Yuji Nakamoto

    2024 ISMRM & ISMRT Annual Meeting & Exhibition  2024.5.6 

  43. Non-Invasive Evaluation of Tumor Microstructure by DWI in Triple-Negative Breast Cancer: Association with CD31 and Vimentin

    A.Otani,¹ M. Iima,²,³ H. Imai,⁴ M.Akamatsu,¹ N. Gotoh,⁵ Y. Takeuchi,⁵ M.Kataoka,³ M. Honda,³ T. Nobashi,³ A. Yoshizawa,⁶ H. Ito,³ T. Nakagawa,³ M. Kim,³ D. Le Bihan,²,³,⁷ S. Naganawa,² Y. Nakamoto³

    The 9th Annual Scientific Meeting of the ISMRM Japanese Chapter  2024.9.21 

  44. MRIによる乳腺腫瘍の評価 血流からのアプローチ

    片岡正子, 本田茉也, 西本あずさ, 岡澤藍夏, 大橋茜, 阪口怜奈, 太田理恵, 飯間麻美, I中本裕士

    日本超音波医学会第98回学術大会  2025.5.30 

  45. JBCS Symposium 2:乳癌免疫療法のリアルワールドでの問題点、そして今後の展望 . Triple Negative乳癌に対する Pembrolizumab併用術前化学療法のMRI評価:-早期治療効果予測の可能性

    片岡正子, 岡澤藍夏, 川島雅央, 川口展子, 河口浩介, 本田茉也, 太田理恵, 飯間麻美, 山田洋介, 竹内康英, 三宅可奈江, 山口絢音, 高田正泰, 中本裕士

    第32回日本乳癌学会学術総会  2024.7.11 

  46. Incorporating DWI in Breast MRI Interpretation Invited

    Mami Iima

    Radiology International Kyoto  2024.4.9 

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    Presentation type:Oral presentation (invited, special)  

  47. DWI Parameters Correlated with Ki-67 Expression, a Prognostic Biomarker, in a Triple-Negative Breast Cancer PDX Mouse Model

    Mami Iima, Tomomi Nobashi, Masako Kataoka, Yuji Nakamoto

    2024 ISMRM & ISMRT Annual Meeting & Exhibition  2024.5.6 

  48. DWI Clinical Applications and Future Directions: Future Direction Including Standardization Invited

    RSNA Scientific Assembly and Annual Meeting  2024.12.4 

  49. DW-MRI Parameters Correlated with PARVA Expression in a Luminal Breast cancer PDX mouse model

    M.Akamatsu, M. Iima, H. Imai, N. Gotoh, Y. Takeuchi, M. Honda, T. Nobashi, M. Kataoka, A. Yoshizawa, H. Ito, T. Nakagawa, M. Kim, D. Le Bihan, S. Naganawa, Y. Nakamoto

    The 9th Annual Scientific Meeting of the ISMRM Japanese Chapter  2024.9.21 

  50. Diffusion MRI of the Breast Invited

    Mami Iima

    The ISMRM-Endorsed Global Outreach Workshop in Thailand 2024  2024.5.11 

  51. Crafting Good Clinical Research Abstracts for ISMRM

    Mami Iima

    ISMRM Abstract Writing Webinar Series: Insights on Clinical & Technical Abstracts, Session III  2025.8.5 

  52. Associations between non-Gaussian diffusion parameters and Ki-67 expression in a PDX model of human triple negative breast cancer

    Sawako Hayami, Mami Iima, Tomomi Nobashi, Yuko Someya, Hirohiko Imai, Denis Le Bihan, Yuji Nakamoto

    2024.1.26 

  53. AIを用いた乳房MRI拡散強調画像における良悪性および分子学的予後予測因子鑑別能の検討

    南 暁彦, 飯間 麻美, 水野良佑, 今西勁峰, 片岡正子, 中本裕士

    第52回日本磁気共鳴医学会大会  2024.9.20 

  54. A Comparative Analysis of 3scan-trace and 3D-diagonal DWI in Breast Lesion Evaluation

    Yusuke Jo, Mami Iima, Yunhao Zhang, Hiroko Satake, Yutaka Kato, Yuki Sato, Kazushige Ichikaw, Ryota Hyodo, Yoshito Ichib, Shinji Naganaw

    第83回日本医学放射線学会学術総会  2025.4 

  55. 乳腺 MRの最近の知見 Invited

    Mami Iima

    遠隔画像診断 講演会 MRI 最新画像診断 愛知診断治療技術振興財団  2025.10.4 

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    Presentation type:Oral presentation (invited, special)  

  56. UF-DCE MRIにおける病変評価の至適タイミング: サブタイプとの関連

    阪口怜奈, 片岡正子, 本田茉也, 飯間麻美, 岡澤藍夏, 太田理恵, 金尾昌太郎, 髙田正泰, 安藤久美子, 中本裕士

    第83回日本医学放射線学会学術総会  2024.4.14 

  57. 次の BI-RADS MRI で拡散強調像はどうなりそう? Invited

    第10回乳腺画像・インターベンション研究会  2024.10.12 

  58. 機械学習による拡散MRI乳がん診断支援システムの開発

    飯間 麻美

    官⺠による若手研究者発掘支援事業 研究発表 東京大学  2024.3.7 

  59. 最新の乳房拡散MRI Invited

    飯間 麻美

    第74回 なにわ臨床画像研究会  2024.2.21 

  60. 最新の乳房MRIと拡散MRI Invited

    湘南乳癌画像診断WEBセミナー  2024.8.19 

  61. 日本乳癌画像研究会 特別WEB講演会 乳房MRIの未来に向けて~臨床は何を求め、技術は何をもたらしうるのか~ ISMRM Workshop on Breast MRI 報告会

    飯間麻美, 片岡正子, 本田茉也

    2026.1.16 

  62. Key Considerations for Obtaining Research Funding in Radiation Medicine

    第83回日本医学放射線学会学術総会  2025.4.13 

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    Presentation type:Symposium, workshop panel (nominated)  

  63. 拡散MRIによる機能画像と放射線治療への応用 Invited

    飯間 麻美

    第3回日本MR画像誘導適応放射線治療研究会  2024.7.6 

  64. 拡散MRIによるがん診断の新たな潮流 Invited

    飯間 麻美

    第25回放射線研究セミナー  2024.4.6 

  65. 忙しいMRI研究者のための研究費獲得のコツ Invited

    飯間 麻美

    2024.9.21 

  66. 卵巣癌間質の腫瘍関連線維症(Tumor-associated fibrosis)と拡散強調MRIの可能性

    Japanese Society for the Advancement of Women's Imaging  2024.10.11 

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    Presentation type:Poster presentation  

  67. 乳房病変におけるhigh-resolution DWIとstandard DWIの比較

    池田明央, 金尾昌太郎, 太田理恵, 片岡正子, 飯間麻美, 本田茉也, 金森直美, 山城大泰, 森井奈央, 久保武

    第52回日本磁気共鳴医学会大会  2024.9.21 

  68. 乳房拡散強調画像における脂肪抑制法(STIR vs SPAIR)の比較:病変と乳房組成の定性的および定量的解析

    飯間麻美, 片岡正子, 大橋茜, 山口健, 井上依里香, 徳田由紀子, 本田茉也, 佐竹弘子, 久保田一徳, 藤岡友之, ルビアンデニス, 長縄慎二, 中本裕士

    第52回日本磁気共鳴医学会大会  2024.9.20 

  69. 乳房ultrafast MRIにおけるview sharingと圧縮センシングの比較検討

    本田茉也, 片岡正子, 飯間麻美, 太田理恵, 岡澤藍夏, 福島康宏, 佐藤史顕, 増田慎三, 岡田務, 中本裕士

    第52回日本磁気共鳴医学会大会  2024.9.20 

  70. 乳がん移植モデルにおける拡散MRIパラメータと組織病理学的特性の相関 Invited

    飯間 麻美

    金沢大学がん進展制御研究所 令和7年度共同利用・共同研究拠点研究成果報告会  2026.2.10 

  71. What's New? -ISMRM2024レポート- ISMRM2024 プログラム委員の立場から Invited

    飯間 麻美

    2024.9.20 

  72. Utility of Diffusion-weighted imaging and Ultrafast DCE MRI to diagnose small-size breast lesions.

    Akane Ohashi, Masako Kataoka, Maya Honda, Mami Iima, Takashi Ishimori, Yuji Nakamoto

    Diffusion Study Group Trainee Day: 24 Hours of DIFFUSION Around the World! 2024年2月2日  2024.2.2 

  73. 高解像度拡散強調画像を用いた腫瘍体積による乳癌薬物療法の治療効果判定および予測

    岡澤藍夏, 片岡正子, 本田茉也, 西本あずさ, 太田理恵, 竹内康英, 飯間麻美, 中本裕士

    第52回日本磁気共鳴医学会大会  2024.9.21 

  74. 非造影MRIによる 乳房病変のカテゴリー分類の検証

    本田茉也, 片岡正子, 太田理恵, 飯間麻美, 岡澤藍夏, 大橋茜, 佐藤史顕, 岡田務

    第33回日本乳癌学会  2025.7.12 

  75. 術前薬物療法中間評価MRIにおける早期効果予測ツールとしての DCE・DWIパラメーター

    片岡正子, 岡澤藍夏, 太田理恵, 本田茉也, 飯間麻美, 竹内康英, 山田洋介, 川島雅央, 髙田正泰, 中本裕士

    第83回日本医学放射線学会学術総会  2024.4.14 

  76. 第2回ミニシンポジウム「マルチタスクの中キャリアを積むこと」

    飯間 麻美

    京都大学KUSNoKIプロジェクト 第2回ミニシンポジウム  2025.2.1 

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    Language:Japanese   Presentation type:Symposium, workshop panel (nominated)  

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KAKENHI (Grants-in-Aid for Scientific Research) 5

  1. Multicenter Collaborative Study on AI-Assisted Next-Generation Abbreviated Breast MRI for High-Precision Breast Cancer Diagnosis in Young Women

    Grant number:25K02602  2025.4 - 2028.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

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    Authorship:Coinvestigator(s) 

  2. 尿道周囲組織の弾性と尿中細菌叢に着目した低活動膀胱に対する新規病態解明

    Grant number:25K12565  2025.4 - 2028.3

    科学研究費助成事業  基盤研究(C)

    松川 宜久, 野宮 正範, 飯間 麻美

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    Authorship:Coinvestigator(s) 

    膀胱収縮力の低下によって、効率よく尿を排出できない低活動膀胱は、高齢者で多く見られ、生活の質を低下や尿路感染、腎機能障害に影響を及ぼすにも関わらず、現時点では有用な治療法が存在しない疾患です。
    本研究では、低活動膀胱における排尿時の尿道機能に着眼して、これらに影響を及ぼす因子や機能低下へと導くメカニズムの解明ならびに尿道機能の簡便な評価法の開発を目的とします。本研究成果は、低活動膀胱の新規治療につながることが期待されます。

  3. 非造影MRIによる乳がん検出・診断のためのバーチャル顕微鏡の創出

    Grant number:24K02402  2024.4 - 2028.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    飯間 麻美, 片岡 正子, 本田 茉也, 西村 友美, 佐竹 弘子, 片岡 正子, 本田 茉也, 西村 友美, 佐竹 弘子

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    Authorship:Principal investigator 

    Grant amount:\18460000 ( Direct Cost: \14200000 、 Indirect Cost:\4260000 )

    乳がん治療においては、がんの各々の特徴に応じた治療法を選択する個別化医療が進んでいる。よって多くの治療法の選択肢の中で最適な治療の選択を可能とする、患者に安全な新たなイメージング技術の開発が重要と考えられる。
    本研究では拡散MRIを含む非造影MRI技術を用いて、機械学習を活用し、乳がんを効率的に検出する方法を開発する。さらには組織を採取せずも乳がんのホルモン受容体やKi-67発現などの病理情報や臨床情報を評価可能な「バーチャル顕微鏡」を創出することにより新たな乳がん診断法の確立を目指す。また、特定の乳がんの染色体変異情報についても非造影MRI定量値との相関を併せて検討する。
    組織内の水分子の拡散運動を画像化可能な機能的画像診断法である拡散強調像を主に活用して複数の深層学習モデルによる乳がん診断システムの開発を行った。病変の手動セグメンテーションを必要とせずとも放射線科医に匹敵する診断能(AUC 0.88、感度85.9%、特異度81.4%)を示した結果を受け、AIの検出機能につき乳癌検出のためDWI(拡散強調画像)にAIを統合するため、腫瘍検出にYOLO v5を用い、悪性度評価に2D CNNを実装して開発した。特に全スライス法(AUC 0.90、感度84.4%、特異度84.0%)とバウンディングボックス法(AUC 0.87、感度87.5%、特異度80.0%)の両方である一定の高い診断性能を示した。本結果は国際磁気共鳴医学会で発表予定である。
    なお、乳がんの染色体変異情報(der(1:16)染色体転座異常)の検討については、FISHの解析に関する手間がかかることがハードルであるが、FISHの解析を自動化するための技術開発を進めた。
    またCEST画像についてはソフトウェアの実装やMRI装置のバージョンの違いなど複数の事項の解決が必要であり、未だ撮影・解析の準備段階である。
    本年度の研究では、乳癌検出のためDWI(拡散強調画像)にAIを統合する結果について、腫瘍検出にYOLO v5を活用し、悪性度評価に2D CNNを用いた二段階アプローチを含め開発した。当初計画していた特定の乳がんの染色体変異情報(der(1:16)染色体転座異常)の詳細な検討については、FISHの解析に関する手間がかかることがハードルであるため、FISHの解析を自動化するための技術開発を進めた。またCEST画像についてはソフトウェアの実装、MRI装置のバージョンの違いにより未だ撮影の準備段階ではある。
    CEST画像については、使用可能なソフトウェアパッケージの開発を外部企業と共同で実施し、装置間の互換性を確保する。並行して既存のDWIデータを用いた解析を継続し、機械学習モデルの診断能に関するさらなる改良に注力する。
    異なるMRI機種間でのファントム比較実験を追加実施し、拡散MRI定量値の標準化を進める。また、多施設共同研究の枠組みを整備し、データ共有とAI開発を推進できる体制を構築する。

  4. Development of high-precision multiparametric imaging of breast cancer for minimally invasive treatment

    Grant number:22K07693  2022.4 - 2025.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

    KATAOKA MASAKO

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    Authorship:Coinvestigator(s) 

    We aimed to delineate the true extent of breast-cancer using high-precision multiparametric imaging, Key achievements include the usefulness of ultrafast dynamic contrast-enhanced (UF-DCE) MRI and high-resolution diffusion-weighted imaging (DWI), clarifying how these methods outperform conventional techniques. A diagnostic decision tree based on high-resolution DWI was constructed, and the combined use of UF-DCE MRI plus DWI proved promising for tumor-subtype prediction. Interim evaluation with high-resolution DWI, especially tumor volumetry showed strong correlation with pathological complete response. We also developed an AI method for automatic quantification of tumor-associated vessels, proposing it as a novel malignancy parameter. Altogether, our results suggest that multiparametric MRI, augmented by metabolic PET imaging, can enable accurate diagnosis, reliable treatment-response assessment, and less-invasive therapies for breast cancer.

  5. 拡散MRIによる新たな乳がん予後予測因子としてのイメージングバイオマーカーの構築

    Grant number:21K07618  2021.4 - 2024.3

    日本学術振興会  科学研究費助成事業 基盤研究(C)  基盤研究(C)

    飯間 麻美

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    本研究では、拡散MRIより得られる様々な定量値を乳がんのサブタイプを始めとする分子生物学的因子や再発、転移や予後、治療効果情報等と関連付けることにより、臨床において汎用性の高いイメージングバイオマーカーを探索する。また、拡散MRI定量値が実際に腫瘍内のどのような特徴を捉えているのか、担がんマウスモデルを作成し組織学的検討を行う。
    動物実験においてはコロナ禍の影響により研究者の移動含め制限の時期が長く続き、実験を本格的に再開始できたのは2021年秋頃からであったため、特に動物実験の進捗状況において遅延が生じている。担がんマウスモデルを作製し前臨床7TMRIにて撮影を行い、CD31やKi-67などの免疫染色を行い、拡散MRIパラメトリックマップと病理組織標本からの免疫染色画像をマップ単位で比較した。拡散MRI定量値が細胞や、血管密度などの病理情報と相関があるか検討を引き続き行っている。
    過去に多数の(拡散強調の度合いを表す)b値で撮影した乳房拡散強調画像(拡散MRI定量値の乳腺腫瘍の良悪性や progesterone receptor statusの鑑別の有用性については論文発表済(Iima et al. Radiology.2018 May;287(2):432-441)を用いて算出される定量値(Kurtosis)が転移予測バイオマーカーとなる可能性を見出した。北米放射線学会において(オンライン)口頭発表を行い、現在論文投稿中である。

 

Media Coverage 1

  1. がんの新たな診断法「拡散MRI」、低負担で高い診断精度を実現 Newspaper, magazine

    日経クロステック 

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    Author:Other 

Academic Activities 24

  1. Unmet Needs with Body DWI, ISMRM Body MRI & Diffusion Study Group Virtual Meeting

    Role(s):Planning, management, etc., Panel moderator, session chair, etc., Supervision (editorial)

    Ryan L. Brunsing, M.D., Ph.D. and Mami Iima, M.D., Ph.D.  2026.2

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    Type:Academic society, research group, etc. 

  2. 第23回 関西乳房MRI勉強会

    Role(s):Panel moderator, session chair, etc.

    2025.10

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    当番世話人

  3. Quality Assurance, Standardization & Benchmarking in Breast MRI ISMRM Workshop on Breast MRI: Technological Advances & Clinical Applications

    Role(s):Panel moderator, session chair, etc.

    Maggie Chung, M.D. & Mami Iima, M.D., Ph.D (座長)  2025.9

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    Type:Competition, symposium, etc. 

  4. 第53回日本磁気共鳴医学会大会 乳腺1 一般演題(口述)

    Role(s):Panel moderator, session chair, etc.

    座長  2025.8

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    Type:Academic society, research group, etc. 

  5. 第2回Japan Breast Radiologists Young Club

    Role(s):Planning, management, etc.

    2025.4

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    Type:Academic society, research group, etc. 

  6. ISMRM Workshop on 40 years of Diffusion: Past, Present & Future Perspectives, Fireside Chat Successes & Pitfalls of Clinical Collaborations

    Role(s):Panel moderator, session chair, etc.

    Mami Iima M.D., PhD.,  2025.2

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    Type:Academic society, research group, etc. 

  7. 第1回Japan Breast Radiologists Young Club Organizer

    Role(s):Planning, management, etc., Panel moderator, session chair, etc.

    2024.7

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    Type:Academic society, research group, etc. 

  8. ISMRM Workshop on Moving Forward with Intravoxel Incoherent Motion Modeling for Diffusion-Weighted MRI An Attempt at Consensus

    Role(s):Planning, management, etc., Panel moderator, session chair, etc., Planning/Implementing academic research

    2024.3

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    Type:Academic society, research group, etc. 

  9. Diffusion Study Group Trainee Day: 24 Hours of DIFFUSION Around the World!

    Role(s):Panel moderator, session chair, etc.

    2024.2

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    Type:Academic society, research group, etc. 

  10. Breast Imaging (Breast MRI and Developing Techniques) , RSNA 2023

    Role(s):Panel moderator, session chair, etc.

    2023.11

  11. 「乳腺診療の未来へ: EUSOBI2023に学ぶ最新の画像診断」乳腺画像・インターベンション研究会2023

    Role(s):Panel moderator, session chair, etc.

    司会  2023.10

  12. ISMRM JPC 2023 The 8th Annual Scientific Meeting of the ISMRM Japanese Chapter Invited Lecture

    座長  2023.9

  13. 第8回Advanced Medical Imaging研究会 「機器・ソフトの進歩 MR」

    座長  2023.7

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    Type:Academic society, research group, etc. 

  14. MRI in Breast Cancer: Update & New Approaches Toward Diagnosis & Treatment ISMRM 2023 Organizer

    Role(s):Planning, management, etc.

    2023.6

  15. 「MRI 実践セミナー(基礎から・いまさら聞けない)」

    日本乳癌画像研究会 座長  2023.2

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    Type:Academic society, research group, etc. 

  16. Breast Imaging (Factors Influencing Breast Screening - Use and Outcomes), RSNA

    2022.11

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    Type:Academic society, research group, etc. 

  17. Diffusion-weighted imaging of the breast: state of the art & beyond、 ISMRM

    2021.5

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    Type:Academic society, research group, etc. 

  18. Ebb & Flow: Perfusion & Permeability from Head to Toe, ISMRM

    2021.5

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    Type:Academic society, research group, etc. 

  19. Breast Imaging (Functional Imaging), RSNA

    2019.12

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    Type:Academic society, research group, etc. 

  20. Breast Imaging (MRI Diagnostics), RSNA

    2019.12

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    Type:Academic society, research group, etc. 

  21. Breast MRI: Current Topics & Future Directions, ISMRM

    2019.5

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    Type:Academic society, research group, etc. 

  22. RSNA abstract reviewer

    Role(s):Peer review

    2018.11

  23. Applications of Diffusion MRI Power Pitch, ISMRM

    2018.6

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    Type:Academic society, research group, etc. 

  24. ISMRM abstract reviewer

    Role(s):Peer review

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