研究者詳細 - 田岡　俊昭

論文 - 田岡　俊昭

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Higher longitudinal brain white matter atrophy rate in aquaporin-4 IgG-positive NMOSD compared with healthy controls 査読有り Open Access

Masuda H., Mori M., Hirano S., Uzawa A., Uchida T., Muto M., Ohtani R., Aoki R., Hirano Y., Iwatsubo T., Asada T., Arai H., Sugishita M., Matsuda H., Ito K., Senda M., Ishii K., Kuwano R., Ikeuchi T., Sato N., Sato H., Shimohama S., Saitoh M., Yamauchi R., Hayashi T., Kobayashi S., Nakano N., Kanazawa J., Ando T., Takanami C., Hareyama M., Hatakenaka M., Tsukamoto E., Ochi S., Shoji M., Matsubara E., Kawarabayashi T., Wakasaya Y., Nakata T., Nakahata N., Ono S., Takai Y., Takahashi S., Yonezawa H., Takahashi J., Kudoh M., Sasaki M., Matsumura Y., Hirata Y., Metoki T., Hayakawa S., Sato Y., Takeda M., Sasaki T., Sera K., Terasaki K., Saitoh Y., Goto S., Ueno K., Sakashita H., Watanabe K., Nagata K., Sato Y., Maeda T., Kondoh Y., Yamazaki T., Takano D., Miyata M., Komatsu H., Watanabe M., Sinoda T., Muraoka R., Kikuchi K., Ito H., Sato A., Kinoshita T., Toyoshima H., Sato K., Sugawara S., Ito I., Kumagai F., Furukawa K., Waragai M., Tomita N., Okamura N., Ootsuki M., Sugawara K., Sugawara S., Mugikura S., Umetsu A., Murata T., Nagasaka T., Kudo Y., Tashiro M., Watanuki S., Nishizawa M., Tokutake T., Ishikawa S., Kishida E., Sato N.

Scientific Reports 13 巻 ( 1 ) 2023年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Scientific Reports

We aimed to compare longitudinal brain atrophy in patients with neuromyelitis optica spectrum disorder (NMOSD) with healthy controls (HCs). The atrophy rate in patients with anti-aquaporin-4 antibody-positive NMOSD (AQP4 + NMOSD) was compared with age-sex-matched HCs recruited from the Japanese Alzheimer’s Disease Neuroimaging Initiative study and another study performed at Chiba University. Twenty-nine patients with AQP4 + NMOSD and 29 HCs were enrolled in the study. The time between magnetic resonance imaging (MRI) scans was longer in the AQP4 + NMOSD group compared with the HCs (median; 3.2 vs. 2.9 years, P = 0.009). The annualized normalized white matter volume (NWV) atrophy rate was higher in the AQP4 + NMOSD group compared with the HCs (median; 0.37 vs. − 0.14, P = 0.018). The maximum spinal cord lesion length negatively correlated with NWV at baseline MRI in patients with AQP4 + NMOSD (Spearman’s rho = − 0.41, P = 0.027). The annualized NWV atrophy rate negatively correlated with the time between initiation of persistent prednisolone usage and baseline MRI in patients with AQP4 + NMOSD (Spearman’s rho = − 0.43, P = 0.019). Patients with AQP4 + NMOSD had a greater annualized NWV atrophy rate than HCs. Suppressing disease activity may prevent brain atrophy in patients with AQP4 + NMOSD.

DOI： 10.1038/s41598-023-38893-1

Open Access

Scopus

Intracranial Air Absorption through Arachnoid Granulation: New Considerations from Transsphenoidal Surgery and Implications for Neurofluid Dynamics Open Access

Naganawa, S; Ito, R; Kawamura, M; Taoka, T

MAGNETIC RESONANCE IN MEDICAL SCIENCES advpub 巻 ( 0 ) 2023年11月

Diffusivity Along the Perivascular Space is Decreased and Related to Hypoperfusion in Adult Moyamoya disease

Shoko Hara, Junko Kikuta, Kaito Takabayashi, Koji Kamagata, Shihori Hayashi, Motoki Inaji, Yoji Tanaka, Masaaki Hori, Kenji Ishii, Tadashi Nariai, Toshiaki Taoka, Shinji Naganawa, Shigeki Aoki, Taketoshi Maehara

2023年10月

Multisite harmonization of diffusion tensor image analysis along the perivascular space using the COMBined Association Test 査読有り Open Access

Saito, Y; Kamagata, K; Andica, C; Taoka, T; Tuerxun, R; Uchida, W; Takabayashi, K; Owaki, M; Yoshida, S; Yamazaki, K; Naganawa, S; Aoki, S

JAPANESE JOURNAL OF RADIOLOGY 41 巻 ( 10 ) 頁： 1072 - 1083 2023年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Japanese Journal of Radiology

Purpose: This multisite study aimed to use the COMBined Association Test (COMBAT), a harmonization technique that uses regression of covariates with an empirical Bayesian framework, to harmonize diffusion tensor image analysis along the perivascular space (DTI-ALPS) variations caused by scanner, site, and protocol differences. Materials and methods: This study included multisite diffusion magnetic resonance imaging (dMRI) data of 45 patients with Alzheimer’s disease (AD) and 82 cognitively normal (CN) participants from the AD neuroimaging initiative database. The dMRI data were obtained with two b values (0 and 1000 s/mm2) from 27 institutions and three different 3-Tesla MRI scanners (two vendors). The ALPS index was calculated from multisite dMRI data, and COMBAT was used to harmonize the factors causing site variations. Welch’s t test was used, Cohen’s d was calculated to compare the difference in the ALPS index between AD and CN before and after harmonization, and Pearson’s correlation coefficient was calculated to assess the relationships between the ALPS index and the cognitive score, [18F] fluorodeoxyglucose (FDG)-positron emission tomography (PET), and [18F] florbetapir (AV45)-PET standardized uptake value ratios (SUVRs). Results: COMBAT harmonized scanner differences and increased Cohen’s d of the left and right ALPS indexes between AD and CN from 0.288 to 0.438 and 0.328 to 0.480, respectively. The ALPS indexes were significantly different between AD and CN after harmonization (P < 0.05) but not before it. Moreover, Pearson’s correlation coefficients between the ALPS index and cognitive score, FDG-PET, and AV45-PET SUVRs were higher after harmonization than before it. Conclusion: This study demonstrates the application of COMBAT harmonization to eliminate between-scanner, site, and protocol variations in the ALPS index calculated from DTI-ALPS using dMRI and possibly facilitate the use of the ALPS index in multi-center studies.

DOI： 10.1007/s11604-023-01432-z

Evaluation of alterations in interstitial fluid dynamics in cases of whole-brain radiation using the diffusion-weighted image analysis along the perivascular space method 招待有り査読有り国際誌 Open Access

Taoka, T; Ito, R; Nakamichi, R; Nakane, T; Kawamura, M; Ishihara, S; Ichikawa, K; Kawai, H; Naganawa, S

NMR IN BIOMEDICINE 頁： e5030 2023年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：NMR in Biomedicine

In the current study, we assessed changes in interstitial fluid dynamics resulting after whole-brain radiotherapy using the diffusion-weighted image analysis along the perivascular space (DWI-ALPS) method, which is a simplified variation of the diffusion tensor image ALPS (DTI-ALPS) method using diffusion-weighted imaging (DWI) with orthogonal motion-probing gradients (MPGs). This retrospective study included 47 image sets from 22 patients who underwent whole-brain radiotherapy for brain tumors. The data for the normal control group comprised 105 image sets from 105 participants with no pathological changes. DWI was performed with the three MPGs applied in an orthogonal direction to the imaging plane, and apparent diffusion coefficient images for the x-, y-, and z-axes were retrospectively generated. The ALPS index was calculated to quantify interstitial fluid dynamics. The independent t-test was used to compare the ALPS index between normal controls and patients who underwent whole-brain radiotherapy. Patients were compared in all age groups and individual age groups (20–39, 40–59, and 60–84 years). We also examined the correlation between biologically equivalent doses (BEDs) and the ALPS index, as well as the correlation between white matter hyperintensity and the ALPS index. In the comparison of all age groups, the ALPS index was significantly lower (p < 0.001) in the postradiation group (1.32 ± 0.16) than in the control group (1.44 ± 0.17), suggesting that interstitial fluid dynamics were altered in patients following whole-brain radiotherapy. Significant age group differences were found (40–59 years: p < 0.01; 60–84 years: p < 0.001), along with a weak negative correlation between BEDs (r = −0.19) and significant correlations between white matter hyperintensity and the ALPS index (r = −0.46 for periventricular white matter, r = −0.38 for deep white matter). It was concluded that the ALPS method using DWI with orthogonal MPGs suggest alteration in interstitial fluid dynamics in patients after whole-brain radiotherapy. Further systematic prospective studies are required to investigate their association with cognitive symptoms.

DOI： 10.1002/nbm.5030

In reply: the improvement technique for reproducibility of diffusion tensor image analysis along the perivascular space (DTI-ALPS) for evaluating interstitial fluid diffusivity and glymphatic function Open Access

Taoka, T

JAPANESE JOURNAL OF RADIOLOGY 41 巻 ( 9 ) 頁： 1031 - 1032 2023年9月

From pituitary adenoma to PitNET: it is time to discuss PitNET/pituitary adenoma Open Access

Fushimi, Y; Taoka, T; Naganawa, S

JAPANESE JOURNAL OF RADIOLOGY 41 巻 ( 8 ) 頁： 787 - 788 2023年8月

Emerging Perspectives on MRI Application in Multiple Sclerosis: Moving from Pathophysiology to Clinical Practice 査読有り国際誌 Open Access

Rocca, MA; Margoni, M; Battaglini, M; Eshaghi, A; Iliff, J; Pagani, E; Preziosa, P; Storelli, L; Taoka, T; Valsasina, P; Filippi, M

RADIOLOGY 307 巻 ( 5 ) 頁： e221512 2023年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Radiology

MRI plays a central role in the diagnosis of multiple sclerosis (MS) and in the monitoring of disease course and treatment response. Advanced MRI techniques have shed light on MS biology and facilitated the search for neuroimaging markers that may be applicable in clinical practice. MRI has led to improvements in the accuracy of MS diagnosis and a deeper understanding of disease progression. This has also resulted in a plethora of potential MRI markers, the importance and validity of which remain to be proven. Here, five recent emerging perspectives arising from the use of MRI in MS, from pathophysiology to clinical application, will be discussed. These are the feasibility of noninvasive MRI-based approaches to measure glymphatic function and its impairment; T1-weighted to T2-weighted intensity ratio to quantify myelin content; classification of MS phenotypes based on their MRI features rather than on their clinical features; clinical relevance of gray matter atrophy versus white matter atrophy; and time-varying versus static resting-state functional connectivity in evaluating brain functional organization. These topics are critically discussed, which may guide future applications in the field.

DOI： 10.1148/radiol.221512

Web of Science

Scopus

PubMed

ALPS-indexを用いた糖尿病と糖尿病前期の病態におけるGlymphatic systemの評価［大会長賞記録］ Open Access

鎌形康司, 内田航, 斎藤勇哉, 高林海斗, 加賀英義, 染谷由希, 明石敏昭, 和田昭彦, 田端宏樹, 内藤仁嗣, 田村好史, 田岡俊昭, 長縄慎二, 河盛隆造, 綿田裕孝, 青木茂樹

日本磁気共鳴医学会雑誌 43 巻 ( 2 ) 頁： 60 - 62 2023年5月

もやもや病にGlymphatic system機能不全は存在するか？—DTI-ALPS indexによる評価—［大会長賞記録］ Open Access

原祥子, 菊田潤子, 高林海斗, 鎌形康司, 林志保里, 稲次基希, 田中洋次, 堀正明, 石井賢二, 成相直, 田岡俊昭, 長縄慎二, 青木茂樹, 前原健寿

日本磁気共鳴医学会雑誌 43 巻 ( 2 ) 頁： 56 - 59 2023年5月

Neuroimaging uncovers distinct relationships of glymphatic dysfunction and motor symptoms in Parkinson's disease 国際誌

Qin, Y; He, RC; Chen, J; Zhou, XX; Zhou, X; Liu, ZH; Xu, Q; Guo, JF; Yan, XX; Jiang, NA; Liao, WH; Taoka, T; Wang, DC; Tang, BS

JOURNAL OF NEUROLOGY 270 巻 ( 5 ) 頁： 2649 - 2658 2023年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Neurology

Background: Studies of glymphatic dysfunction in Parkinson’s disease (PD) patients have attracted much attention in recent years. However, the relationships between glymphatic dysfunction and clinical symptoms remains unclear. Objectives: To determine whether the diffusion tensor image analysis along the perivascular space (DTI-ALPS) affect the severity and types of motor and non-motor symptoms in PD patients. Methods: De novo PD patients and controls who performed both DTI and 123I-DaTscan single photon emission computed tomography (SPECT) scanning were retrieved from the international multicenter Parkinson’s Progression Marker Initiative (PPMI) cohort. Glymphatic system was evaluated by the DTI-ALPS. Motor symptoms were assessed by Movement Disorders Society Unified Parkinson’s Disease Rating Scale III (MDS-UPDRS-III). The influence of glymphatic activity on motor and non-motor symptoms was explored by multivariate linear regression models. Results: A total of 153 PD patients (mean age 60.97 ± 9.47 years; 99 male) and 67 normal controls (mean age 60.10 ± 10.562 years; 43 male) were included. The DTI-ALPS index of PD patients was significantly lower than normal controls (Z = − 2.160, p = 0.031). MDS-UPDRS III score (r = − 0.213, p = 0.008) and subscore for rigidity (r = − 0.177, p = 0.029) were negatively correlated with DTI-ALPS index. The DTI-ALPS index was significantly associated with MDS-UPDRS-III score (β = − 0.160, p = 0.048) and subscore for rigidity (β = − 0.170, p = 0.041) after adjusting for putamen dopamine transporter availability and clinical factors. Conclusions: Our results showed distinct relationships between glymphatic dysfunction and the severity and types of PD motor symptoms, suggesting the potential of DTI-ALPS index as a biomarker for PD motor symptoms.

DOI： 10.1007/s00415-023-11594-5

Web of Science

Scopus

PubMed

もやもや病にGlymphatic system機能不全は存在するか? DTI-ALPS indexによる評価 Open Access

原祥子, 菊田潤子, 高林海斗, 鎌形康司, 林志保里, 稲次基希, 田中洋次, 堀正明, 石井賢二, 成相直, 田岡俊昭, 長縄慎二, 青木茂樹, 前原健寿

日本磁気共鳴医学会雑誌 43 巻 ( 2 ) 頁： 56 - 59 2023年5月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：(一社)日本磁気共鳴医学会

もやもや病のGlymphatic system(GS)について、DTI analysis along the perivascular space(DTI-ALPS index)を用いて検討した。成人もやもや病患者46名(男性13名、女性33名、平均38.4歳)と年齢、性別の合致した健常人34名(男性7名、女性27名、平均40.1歳)を対象とし、3T機でEPIシーケンスによる拡散MRIとMPRAGE法による3DT1強調像を撮影した。患者全例で認知機能検査としてTrail Making Test(TMT)を行った。もやもや病のDTI-ALPS indexは健常人より有意に低く、脳実質水成分と負の相関を示した。DTI-ALPS indexはPETのパラメータのうち、脳灌流圧の逆波である平均通過時間(MTT)と有意な負の相関を示した。遂行機能障害が強いほど点数が高くなるTMT-Bは左半球のDTI-ALPS indexと有意な負の相関を示した。もやもや病では脳循環不全の程度に応じてGS機能不全が存在し、脳実質の水成分増加を生じ、認知機能障害と関連する可能性があると考えられた。

DOI： 10.2463/jjmrm.2022-1774

Open Access

特集臨床MRIを基礎から知る−さまざまな角度からMRIの魅力に迫る− [頭部領域] 頭部外傷

田岡俊昭

臨床画像 39 巻 ( 13 ) 頁： 40 - 45 2023年4月

Glymphatic system impairment in nonathlete older male adults who played contact sports in their youth associated with cognitive decline: A diffusion tensor image analysis along the perivascular space study 査読有り国際誌 Open Access

Morita, Y; Kamagata, K; Andica, C; Takabayashi, K; Kikuta, J; Fujita, S; Samoyeau, T; Uchida, W; Saito, Y; Tabata, H; Naito, H; Someya, Y; Kaga, H; Tamura, Y; Miyata, M; Akashi, T; Wada, A; Taoka, T; Naganawa, S; Watada, H; Kawamori, R; Abe, O; Aoki, S

FRONTIERS IN NEUROLOGY 14 巻頁： 1100736 - 1100736 2023年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Frontiers in Neurology

Background and purpose: Exposure to contact sports in youth causes brain health problems later in life. For instance, the repetitive head impacts in contact sports might contribute to glymphatic clearance impairment and cognitive decline. This study aimed to assess the effect of contact sports participation in youth on glymphatic function in old age and the relationship between glymphatic function and cognitive status using the analysis along the perivascular space (ALPS) index. Materials and methods: A total of 52 Japanese older male subjects were included in the study, including 12 who played heavy-contact sports (mean age, 71.2 years), 15 who played semicontact sports (mean age, 73.1 years), and 25 who played noncontact sports (mean age, 71.3 years) in their youth. All brain diffusion-weighted images (DWIs) of the subjects were acquired using a 3T MRI scanner. The ALPS indices were calculated using a validated semiautomated pipeline. The ALPS indices from the left and right hemispheres were compared between groups using a general linear model, including age and years of education. Furthermore, partial Spearman's rank correlation tests were performed to assess the correlation between the ALPS indices and cognitive scores (Mini-Mental State Examination and the Japanese version of the Montreal Cognitive Assessment [MoCA-J]) after adjusting for age years of education and HbA1c. Results: The left ALPS index was significantly lower in the heavy-contact and semicontact groups than that in the noncontact group. Although no significant differences were observed in the left ALPS index between the heavy-contact and semicontact groups and in the right ALPS index among groups, a trend toward lower was found in the right ALPS index in individuals with semicontact and heavy-contact compared to the noncontact group. Both sides' ALPS indices were significantly positively correlated with the MoCA-J scores. Conclusion: The findings indicated the potential adverse effect of contact sports experience in youth on the glymphatic system function in old age associated with cognitive decline.

DOI： 10.3389/fneur.2023.1100736

Neuroimaging findings related to glymphatic system alterations in older adults with metabolic syndrome 国際誌 Open Access

Andica, C; Kamagata, K; Takabayashi, K; Kikuta, J; Kaga, H; Someya, Y; Tamura, Y; Kawamori, R; Watada, H; Taoka, T; Naganawa, S; Aoki, S

NEUROBIOLOGY OF DISEASE 177 巻頁： 105990 - 105990 2023年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Neurobiology of Disease

Objective: The glymphatic system is a glial-based perivascular network that promotes brain metabolic waste clearance. Reduced glymphatic flow has been observed in rat models of type 2 diabetes and hypertension, indicating the role of vascular risk factors in the glymphatic system. However, little is known about how vascular risk factors affect the human glymphatic system. The present study aims to assess the relationships between metabolic syndrome (MetS), a cluster of vascular risk factors, and the glymphatic system function using diffusion magnetic resonance imaging (MRI)-based measures of water diffusivity in the glymphatic compartments, including the brain interstitial space and perivascular spaces around the deep medullary vein. We hypothesized that vascular risk factors are associated with glymphatic dysfunction, leading to cognitive impairment in older adults. Methods: This cross-sectional study assessed 61 older adults (age range, 65–82 years) who had participated in the Bunkyo Health Study, including 15 healthy controls (mean age, 70.87 ± 4.90 years) and 46 individuals with MetS (mean age, 71.76 ± 4.61 years). Fractional volume of extracellular-free water (FW) and an index of diffusion tensor imaging along the perivascular space (DTI-ALPS) were used as indirect indicators of water diffusivity in the interstitial extracellular and perivenous spaces of white matter, respectively. Results: After adjusting for age, sex, years of education, total Fazekas scale, Pittsburgh sleep quality index (PSQI) score, and intracranial volume (ICV), a significantly (P = 0.030; Cohen's d = 1.01) higher FW was observed in individuals with MetS than in the healthy controls. Furthermore, individuals with MetS had a significantly (P = 0.031; Cohen's d = 0.86) lower ALPS index than the healthy controls, with age, sex, years of education, total Fazekas scale, PSQI score, ICV, fractional anisotropy, and mean diffusivity included as confounding factors. Higher FW was significantly associated with lower ALPS index (r = −0.37; P = 0.004). Multiple linear regression (MLR) with backward elimination analyses showed that higher diastolic blood pressure (BP; standardized β = 0.33, P = 0.005) was independently associated with higher FW, whereas higher fasting plasma glucose levels (standardized β = −0.63, P = 0.002) or higher Brinkman index of cigarette consumption cumulative amount (standardized β = −0.27, P = 0.022) were associated with lower ALPS index. The lower ALPS index (standardized β, 0.28; P = 0.040) was associated with poorer global cognitive performance, which was determined using the Japanese version of the Montreal Cognitive Assessment (MOCA-J) scores. Finally, partial correlation analyses showed a significant correlation between higher FW and lower MOCA-J scores (r = −0.35; P = 0.025) and between higher FW and higher diastolic BP (r = 0.32, P = 0.044). Conclusion: The present study shows the changes in diffusion MRI-based measures reflected by the higher FW and lower ALPS index in older adults with MetS, possibly due to the adverse effect of vascular risk factors on the glymphatic system. Our findings also indicate the associations between the diffusion MRI-based measures and elevated diastolic BP, hyperglycemia, smoking habit, and poorer cognitive performance. However, owing to the limitations of this study, the results should be cautiously interpreted.

DOI： 10.1016/j.nbd.2023.105990

Association between the Putative Meningeal Lymphatics at the Posterior Wall of the Sigmoid Sinus and Delayed Contrast-agent Elimination from the Cerebrospinal Fluid Open Access

Naganawa, S; Ito, R; Kawamura, M; Taoka, T; Yoshida, T; Sone, M

MAGNETIC RESONANCE IN MEDICAL SCIENCES 23 巻 ( 1 ) 頁： 80 - 91 2023年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Magnetic Resonance in Medical Sciences

Purpose: To investigate the characteristics of the putative meningeal lymphatics located at the posterior wall of the sigmoid sinus (PML-PSS) in human subjects imaged before and after intravenous administration (IV) of a gadolinium-based contrast agent (GBCA). The appearance of the PML-PSS and the enhancement of the perivascular space of the basal ganglia (PVS-BG) were analyzed for an association with gender, age, and clearance of the GBCA from the cerebrospinal fluid (CSF). Methods: Forty-two patients with suspected endolymphatic hydrops were included. Heavily T2-weighted 3D-fluid attenuated inversion recovery (hT2w-3D-FLAIR) and 3D-real inversion recovery (IR) images were obtained at pre-administration, immediately post-administration, and at 4 and 24 hours after IV-GBCA. The appearance of the PML-PSS and the presence of enhancement in the PVS-BG were analyzed for a relationship with age, gender, contrast enhancement of the CSF at 4 hours after IV-GBCA, and the washout ratio of the GBCA in the CSF from 4 to 24 hours after IV-GBCA. Results: The PML-PSS and PVS-BG were seen in 23 of 42 and 21 of 42 cases, respectively, at 4 hours after IV-GBCA. In all PML-PSS positive cases, hT2w-3D-FLAIR signal enhancement was highest at 4 hours after IV-GBCA. A multivariate analysis between gender, age, CSF signal elevation at 4 hours, and washout ratio indicated that only the washout ratio was independently associated with the enhancement of the PML-PSS or PVS-BG. The odds ratios (95% CIs; P value) were 4.09 × 10–5 (2.39 × 10–8 – 0.07; 0.0078) for the PML-PSS and 1.7 × 10–4 (1.66 × 10–7 – 0.174; 0.014) for the PVS-BG. Conclusion: The PML-PSS had the highest signal enhancement at 4 hours after IV-GBCA. When the PML-PSS was seen, there was also often enhancement of the PVS-BG at 4 hours after IV-GBCA. Both observed enhancements were associated with delayed GBCA excretion from the CSF.

DOI： 10.2463/mrms.mp.2022-0110

Pitfalls of Using T2-contrast Enhancement Techniques in 3D-FLAIR to Detect Endolymphatic Hydrops Open Access

Kato, Y; Naganawa, S; Taoka, T; Yoshida, T; Sone, M

MAGNETIC RESONANCE IN MEDICAL SCIENCES 22 巻 ( 3 ) 頁： 335 - 344 2023年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Magnetic Resonance in Medical Sciences

Purpose: To determine whether T2-contrast enhancement techniques can be used to diagnose endolym-phatic hydrops, we compared fluid signal artifacts with and without T2-contrast enhancement techniques in 3D fluid-attenuated inversion recovery (3D-FLAIR). Methods: We prepared a custom-made phantom consisting of eight tubes half-filled with saline. Images were obtained using four 3D-FLAIR: without T2-contrast enhancement (Normal), with non-selective T2-inversion recovery (T2-IR), and two with non-selective T2 preparation IR (T2-prep). Scans were performed with and without rice covering the phantom to simulate minimal and severe B0-inhomogeneity conditions. The average signal intensity (SI) values of eight saline tubes were compared between the four sequences and between each other. Comparisons were performed for all measurement slices and the central 10 slices. The images using T2-contrast enhancement technique were obtained from a volunteer and a patient suspected of Meniere’sdisease. Results: The Normal sequence SI for all slices was significantly lower than that for the other sequences, with smaller standard deviation (SD) and no outliers. Several outliers were detected in the other sequences. The SDs and outliers were larger without rice than with rice. When the central 10 slices with rice, the T2-IR had a significantly higher SI with more outliers compared with the Normal sequence. The T2-prep had no outliers and SIs that were comparable to those of the Normal sequence. However, without rice, the T2-IR and T2-prep sequences had significantly higher SIs with outliers and larger SDs compared to the Normal sequence. In the corresponding images, the Normal sequence achieved excellent fluid suppression, whereas the T2-IR and T2-prep sequences showed high-signal artifacts. Imperfect fluid suppressions were observed in the volunteer image and the endolymphatic hydrops on the post-gadolinium image differed in size and shape in the non-injected T2-IR in the patient image. Conclusion: T2-contrast enhancement techniques should be used with caution in 3D-FLAIR for diagnosing endolymphatic hydrops.

DOI： 10.2463/mrms.mp.2022-0017

Effect of Temporal Sampling Rate on Estimates of the Perfusion Parameters for Patients with Moyamoya Disease Assessed with Simultaneous Multislice Dynamic Susceptibility Contrast-enhanced MR Imaging Open Access

Takamura, T; Hara, S; Nariai, T; Ikenouchi, Y; Suzuki, M; Taoka, T; Ida, M; Ishigame, K; Hori, M; Sato, K; Kamagata, K; Kumamaru, K; Oishi, H; Okamoto, S; Araki, Y; Uda, K; Miyajima, M; Maehara, T; Inaji, M; Tanaka, Y; Naganawa, S; Kawai, H; Nakane, T; Tsurushima, Y; Onodera, T; Nojiri, S; Aoki, S

MAGNETIC RESONANCE IN MEDICAL SCIENCES 22 巻 ( 3 ) 頁： 301 - 312 2023年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Magnetic Resonance in Medical Sciences

Purpose: The effect of temporal sampling rate (TSR) on perfusion parameters has not been fully investigated in Moyamoya disease (MMD); therefore, this study evaluated the influence of different TSRs on perfusion parameters quantitatively and qualitatively by applying simultaneous multi-slice (SMS) dynamic susceptibility contrast-enhanced MR imaging (DSC-MRI). Methods: DSC-MRI datasets were acquired from 28 patients with MMD with a TSR of 0.5 s. Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and time to maximum tissue residue function (Tmax) were calculated for eight TSRs ranging from 0.5 to 4.0 s in 0.5-s increments that were subsampled from a TSR of 0.5 s datasets. Perfusion measurements and volume for chronic ischemic (Tmax ≥ 2 s) and non-ischemic (Tmax < 2 s) areas for each TSR were compared to measurements with a TSR of 0.5 s, as was visual perfusion map analysis. Results: CBF, CBV, and Tmax values tended to be underestimated, whereas MTT and TTP values were less influenced, with a longer TSR. Although Tmax values were overestimated in the TSR of 1.0 s in non-ischemic areas, differences in perfusion measurements between the TSRs of 0.5 and 1.0 s were generally minimal. The volumes of the chronic ischemic areas with a TSR ≥ 3.0 s were significantly underestimated. In CBF and CBV maps, no significant deterioration was noted in image quality up to 3.0 and 2.5 s, respectively. The image quality of MTT, TTP, and Tmax maps for the TSR of 1.0 s was similar to that for the TSR of 0.5 s but was significantly deteriorated for the TSRs of ≥ 1.5 s. Conclusion: In the assessment of MMD by SMS DSC-MRI, application of TSRs of ≥ 1.5 s may lead to deterioration of the perfusion measurements; however, that was less influenced in TSRs of ≤ 1.0 s.

DOI： 10.2463/mrms.mp.2021-0162

Parasagittal Cystic Lesions May Arise from the Pial Sheath around the Cortical Venous Wall Open Access

Naganawa, S; Ito, R; Taoka, T; Yoshida, T; Sone, M

MAGNETIC RESONANCE IN MEDICAL SCIENCES 22 巻 ( 1 ) 頁： 143 - 146 2023年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Magnetic Resonance in Medical Sciences

It has been reported that perivenous cystic structures near the parasagittal dura are associated with the leakage of gadolinium-based contrast agents at 4 hours after intravenous administration. The origin of such cystic structures remains unknown. While reading many cases of MR cisternography, we noticed that some of the cystic structures appeared to connect to the perivenous subpial space. This new imaging finding might facilitate future research of the waste clearance system for the central nervous system.

DOI： 10.2463/mrms.bc.2021-0141

Peripheral Retinal Leakage after Intravenous Administration of a Gadolinium-based Contrast Agent: Age Dependence, Temporal and Inferior Predominance and Potential Implications for Eye Homeostasis Open Access

Naganawa, S; Ito, R; Kawamura, M; Taoka, T; Yoshida, T; Sone, M

MAGNETIC RESONANCE IN MEDICAL SCIENCES 22 巻 ( 1 ) 頁： 45 - 55 2023年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Magnetic Resonance in Medical Sciences

Purpose: Peripheral retinal leakage (PRL) of contrast medium from the ora serrata (i.e., the peripheral part of the retina) was recently reported in normal eyes using ultra-widefield fluorescein angiography. We occasionally see PRL of gadolinium-based contrast agents (GBCAs) in the vitreous from the temporal and inferior sides of the ora serrata on MR images of subjects without ophthalmic disease. In this study, we retrospectively evaluated these MR images to determine if PRL was associated with aging. We also evaluated whether the initial leakage appeared in the temporal and inferior sides, and whether there was uniform distribution within the vitreous after 24 hours. Methods: In 127 subjects (9 volunteers, 85 patients with sudden deafness, and 33 patients with a suspicion of endolymphatic hydrops), pre-and post-contrast-enhanced heavily T2-weighted 3D-fluid attenuated inversion recovery (FLAIR) images were obtained. The presence or absence of PRL was subjectively evaluated. For patients with a suspicion of endolymphatic hydrops, 3D-real inversion recovery (IR) images were also obtained at pre-, 10 mins, 4 hours, and 24 hours after intravenous administration (IV) of GBCA. Four circular ROIs were placed in the vitreous humor and the signal intensity was measured. Results: In the cases with PRL (n = 88) and without PRL (n = 47), the median age was 59 and 47 years, respectively (P = 0.001). At 4 hours after IV-GBCA, the mean signal increase in the inferior temporal ROI was greater than all the other ROIs. At 24 hours after IV-GBCA, no significant difference in signal intensity was observed for the four ROIs. Conclusion: PRL of GBCA is age-dependent and occurs mainly from the inferior temporal side of the ora serrata. The contrast effect was uniformly distributed at 24 hours after IV-GBCA. Future observations in a variety of diseases will determine the clinical significance of these findings.

DOI： 10.2463/mrms.mp.2021-0100

<田岡 俊昭>

論文 - 田岡 俊昭

<田岡　俊昭>

論文 - 田岡　俊昭