Ryusuke Irie1, Kohei Tsuruta2, Masaaki Hori3, Michimasa Suzuki3, Koji Kamagata3, Atsushi Nakanishi3, Kouhei Kamiya4, Madoka Nakajima5, Masakazu Miyajima5, Hajime Arai5, Shigeki Aoki3. 1. Department of Radiology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan. ririe@juntendo.ac.jp. 2. Department of Radiological Sciences, Tokyo Metropolitan University Graduate School of Human Health Sciences, Tokyo, Japan. 3. Department of Radiology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan. 4. Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. 5. Department of Neurosurgery, Juntendo University School of Medicine, Tokyo, Japan.
Abstract
PURPOSE: To evaluate diffusional changes of the corticospinal tract (CST) in patients with idiopathic normal pressure hydrocephalus (iNPH) by neurite orientation dispersion and density imaging (NODDI). MATERIALS AND METHODS: Nineteen patients with iNPH and 12 healthy controls were included. Diffusion MRI data for NODDI were acquired with a 3-T system, using 32 motion-probing gradient directions with six b-values (from 0 to 2500 s/mm2). The orientation dispersion index (ODI), intra-cellular volume fraction (Vic), and isotropic volume fraction (Viso) of the CST were calculated by tract-specific analysis in patients and controls. We also measured the fractional anisotropy (FA) and apparent diffusion coefficient (ADC). RESULTS: The ODI of the CST (0.087 ± 0.024 vs. 0.183 ± 0.051, P < 0.01, Mann-Whitney U test) and Vic of the CST (0.551 ± 0.061 vs. 0.628 ± 0.038, P < 0.01, Mann-Whitney U test) were significantly lower in iNPH patients than in healthy controls. In receiver-operating characteristic analysis, the area under the curve (AUC) of the ODI and FA were not significantly different (Fig. 4a, 0.987 vs. 0.904, P = 0.061), and the AUC of the Vic and ADC also showed no significant difference (Fig. 4b, 0.864 vs. 0.912, P = 0.194). CONCLUSION: The NODDI can effectively evaluate the condition of neurites in the CST of iNPH patients, and the ODI could be clinically useful in the diagnosis of iNPH.
PURPOSE: To evaluate diffusional changes of the corticospinal tract (CST) in patients with idiopathic normal pressure hydrocephalus (iNPH) by neurite orientation dispersion and density imaging (NODDI). MATERIALS AND METHODS: Nineteen patients with iNPH and 12 healthy controls were included. Diffusion MRI data for NODDI were acquired with a 3-T system, using 32 motion-probing gradient directions with six b-values (from 0 to 2500 s/mm2). The orientation dispersion index (ODI), intra-cellular volume fraction (Vic), and isotropic volume fraction (Viso) of the CST were calculated by tract-specific analysis in patients and controls. We also measured the fractional anisotropy (FA) and apparent diffusion coefficient (ADC). RESULTS: The ODI of the CST (0.087 ± 0.024 vs. 0.183 ± 0.051, P < 0.01, Mann-Whitney U test) and Vic of the CST (0.551 ± 0.061 vs. 0.628 ± 0.038, P < 0.01, Mann-Whitney U test) were significantly lower in iNPH patients than in healthy controls. In receiver-operating characteristic analysis, the area under the curve (AUC) of the ODI and FA were not significantly different (Fig. 4a, 0.987 vs. 0.904, P = 0.061), and the AUC of the Vic and ADC also showed no significant difference (Fig. 4b, 0.864 vs. 0.912, P = 0.194). CONCLUSION: The NODDI can effectively evaluate the condition of neurites in the CST of iNPH patients, and the ODI could be clinically useful in the diagnosis of iNPH.
Entities:
Keywords:
Diffusion MRI; Idiopathic normal pressure hydrocephalus; Neurite orientation dispersion and density imaging; Tract-specific analysis
Authors: Anthony Marmarou; Harold F Young; Gunes A Aygok; Satoshi Sawauchi; Osamu Tsuji; Takuji Yamamoto; Jana Dunbar Journal: J Neurosurg Date: 2005-06 Impact factor: 5.115