Faculty Profiles - NAGANAWA, Shinji

ドパミントランスポータシンチグラフィにおける解析ソフトの有用性に関する研究

Dual Energy CTによる小型肺癌の造影評価

島本宏矩, 岩野信吾, 馬越弘泰, 伊藤倫太郎, 長縄慎二

Japanese Journal of Radiology Vol. 35 ( Suppl. ) page： 34 - 34 2017.2

胸壁並行断面CTを用いた間質性肺炎の定量的評価

馬越弘泰, 岩野信吾, 伊藤倫太郎, 長縄慎二

Japanese Journal of Radiology Vol. 35 ( Suppl. ) page： 34 - 34 2017.2

松澤伸一郎, 加藤克彦, 国本啓太, 本田将之, 椋本竜斗, 小田川哲郎, 阿部真治, 藤田尚利, 櫻木庸博, 伊藤信嗣, 伊藤倫太郎, 岩野信吾, 長縄慎二

核医学 Vol. 54 ( 1 ) page： 663 - 663 2017.2

FDG-PETによる非小細胞肺癌の予後予測因子の検討 SUVmaxと体積を考慮した指標の比較

伊藤信嗣, 岩野信吾, 伊藤倫太郎, 長縄慎二, 加藤克彦

核医学 Vol. 54 ( 1 ) page： 565 - 565 2017.2

Structure of the Medullary Veins of the Cerebral Hemisphere and Related Disorders. Reviewed

Toshiaki Taoka, Akio Fukuisumi, Toshiteru Miyasaka, Hisashi Kawai, Toshiki Nakane, Kimihiko Kichikawa, Shinji Naganawa

Radiographics. Vol. 37 ( 1 ) page： 281-297 2017.1

Endolymphatic hydrops in patients with unilateral and bilateral Meniere's disease.

Kyoko Morimoto, Tadao Yoshida, Saiko Sugiura, Masahiro Kato, Ken Kato, Masaaki Teranishi, Shinji Naganawa, Tsutomu Nakashima, Michihiko Sone

Acta Otolaryngol. Vol. 137 ( 1 ) page： 23-28 2017.1

Visualization of Middle Ear Ossicles in Elder Subjects with Ultra-short Echo Time MR Imaging Reviewed Open Access

Shinji Naganawa, Toshiki Nakane, Hisashi Kawai, Toshiaki Taoka, Kojiro Suzuki, Shingo Iwano, Hiroko Satake, David Grodzki

MAGNETIC RESONANCE IN MEDICAL SCIENCES Vol. 16 ( 2 ) page： 93 - 97 2017

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：JPN SOC MAGNETIC RESONANCE MEDICINE

Purpose: To evaluate the visualization of middle ear ossicles by ultra-short echo time magnetic resonance (MR) imaging at 3T in subjects over 50 years old.
Materials and Methods: Sixty ears from 30 elder patients that underwent surgical or interventional treatment for neurovascular diseases were included (ages: 50-82, median age: 65; 10 men, 20 women). Patients received follow-up MR imaging including routine T1-and T2-weighted images, time-of-flight MR angiography, and ultra-short echo time imaging (PETRA, pointwise encoding time reduction with radial acquisition). All patients underwent computed tomography (CT) angiography before treatment. Thin-section source CT images were correlated with PETRA images. Scan parameters for PETRA were: TR 3.13, TE 0.07, flip angle 6 degrees, 0.83 x 0.83 x 0.83 mm resolution, 3 min 43 s scan time. Two radiologists retrospectively evaluated the visibility of each ossicular structure as positive or negative using PETRA images. The structures evaluated included the head of the malleus, manubrium of the malleus, body of the incus, long process of the incus, and the stapes. Signal intensity of the ossicles was classified as: between labyrinthine fluid and air, similar to labyrinthine fluid, between labyrinthine fluid and cerebellar parenchyma, or higher than cerebellar parenchyma.
Results: In all ears, the body of the incus was visible. The head of the malleus was visualized in 36/60 ears. The manubrium of the malleus and long process of the incus was visualized in 1/60 and 4/60 ears, respectively. The stapes were not visualized in any ear. Signal intensity of the visible structures was between labyrinthine fluid and air in all ears.
Conclusion: The body of the incus was consistently visualized with intensity between air and labyrinthine fluid on PETRA images in aged subjects. Poor visualization of the manubrium of the malleus, long process of the incus, and the stapes limits clinical significance of middle ear imaging with current PETRA methods.

DOI： 10.2463/mrms.mp.2015-0171

Gd-based Contrast Enhancement of the Perivascular Spaces in the Basal Ganglia Reviewed Open Access

Shinji Naganawa, Toshiki Nakane, Hisashi Kawai, Toshiaki Taoka

MAGNETIC RESONANCE IN MEDICAL SCIENCES Vol. 16 ( 1 ) page： 61 - 65 2017

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：JPN SOC MAGNETIC RESONANCE IN MEDICINE

Purpose: In textbooks, the perivascular space (PVS) is described as non-enhancing after the intravenous administration of gadolinium-based contrast agent (IV-GBCA). We noticed that the PVS sometimes has high signal intensity (SI) on heavily T-2-weighted 3D-FLAIR (hT(2)-FL) images obtained 4 h after IV-GBCA. The purpose of this study was to retrospectively evaluate the contrast enhancement of the PVS.
Materials and Methods: In 8 healthy subjects and 19 patients with suspected endolymphatic hydrops, magnetic resonance cisternography (MRC) and hT(2)-FL images were obtained before and 4 h after a single dose of IV-GBCA. No subjects had renal insufficiency. On axial MRC at the level of the anterior commissure (AC)-posterior commissure (PC) line, 1 cm circular regions of interest (ROIs) were drawn centering on the PVS in the bilateral basal ganglia and thalami. Three-millimeter diameter ROIs were set in the cerebrospinal fluid (CSF) of the bilateral ambient cistern. The ROIs on MRC were copied onto the hT2-FL images and the SI was measured. The SI ratio (SIR) was defined as SIRPVS = SI of PVS/SI of the thalami, and SIRCSF = SI of CSF/SI of the thalami. The average of the bilateral values was used for the calculation. The SIRCSF, SIRPVS, and SI of the thalami were compared between before and 4 h after IV-GBCA.
Results: The SIR was increased significantly from 1.02 +/- 0.37 to 2.65 +/- 0.82 in the CSF (P < 0.01) and from 1.20 +/- 0.35 to 2.13 +/- 1.23 in the PVS at 4 h after IV-GBCA (P < 0.01). The SI of the thalami showed no significant difference.
Conclusion: The enhancement of the PVS at 4 h after IV-GBCA was confirmed even in subjects without renal insufficiency. It is possible that the GBCA in the blood vessels might have permeated into the cerebrospinal fluid (CSF) space and the PVS. This might be a first step in the imaging evaluation of the glymphatic system (waste clearance system) of the brain.

DOI： 10.2463/mrms.mp.2016-0039

Quantitative evaluation of interstitial pneumonia using 3D-curved high-resolution CT imaging parallel to the chest wall: A pilot study. Reviewed International journal Open Access

Hiroyasu Umakoshi, Shingo Iwano, Tsutomu Inoue, Yuanzhong Li, Shinji Naganawa

PloS one Vol. 12 ( 9 ) page： e0185532 2017

Language：English Publishing type：Research paper (scientific journal)

OBJECTIVES: To quantify the imaging findings of patients with interstitial pneumonia (IP) and emphysema using three-dimensional curved high-resolution computed tomography (3D-cHRCT) at a constant depth from the chest wall, and compare the results to visual assessment of IP and each patient's diffusing capacity of the lungs for carbon monoxide (DLco). METHODS: We retrospectively reviewed the axial CT findings and pulmonary function test results of 95 patients with lung cancer (72 men and 23 women, aged 45-84 years) with or without IP, as follows: non-IP (n = 47), mild IP (n = 31), and moderate IP (n = 17). The 3D-cHRCT images of the lung at a 1-cm depth from the chest wall were reconstructed automatically using original software; total area (TA), high-attenuation area (HAA) >-500 HU, and low-attenuation area (LAA) <-950 HU were calculated on a workstation. The %HAA and %LAA were calculated as follows: [Formula: see text], and [Formula: see text]. RESULTS: The %HAA and %LAA respective values were 3.2±0.9 and 27.7±8.2, 3.9±1.2 and 27.6±5.9, and 6.9±2.2 and 25.4±8.7 in non-IP, mild IP, and moderate IP patients, respectively. There were significant differences in %HAA between the 3 groups of patients (P<0.001), but no differences in %LAA (P = 0.558). Multiple linear regression analysis revealed that %HAA and %LAA were negatively correlated with predicted DLco (standard partial regression coefficient [b*] = -0.453, P<0.001; b* = -0.447, P<0.001, respectively). CONCLUSIONS: The %HAA and %LAA values computed using 3D-cHRCT were significantly correlated with DLco and may be important quantitative parameters for both IP and emphysema.

DOI： 10.1371/journal.pone.0185532