Ikuko Uwano1, Kohsuke Kudo2, Fumio Yamashita1, Jonathan Goodwin2, Satomi Higuchi1, Kenji Ito1, Taisuke Harada2, Akira Ogawa3, Makoto Sasaki1. 1. Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Yahaba, Iwate 028-3694, Japan. 2. Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Yahaba, Iwate 028-3694, Japan and Department of Diagnostic and Interventional Radiology, Hokkaido University Hospital, Sapporo, Hokkaido 060-8648, Japan. 3. Department of Neurosurgery, Iwate Medical University, Morioka, Iwate 020-8505, Japan.
Abstract
PURPOSE: To evaluate the performance and efficacy for intensity inhomogeneity correction of various sequences of the human brain in 7T MRI using the extended version of the unified segmentation algorithm. MATERIALS: Ten healthy volunteers were scanned with four different sequences (2D spin echo [SE], 3D fast SE, 2D fast spoiled gradient echo, and 3D time-of-flight) by using a 7T MRI system. Intensity inhomogeneity correction was performed using the "New Segment" module in SPM8 with four different values (120, 90, 60, and 30 mm) of full width at half maximum (FWHM) in Gaussian smoothness. The uniformity in signals in the entire white matter was evaluated using the coefficient of variation (CV); mean signal intensities between the subcortical and deep white matter were compared, and contrast between subcortical white matter and gray matter was measured. The length of the lenticulostriate (LSA) was measured on maximum intensity projection (MIP) images in the original and corrected images. RESULTS: In all sequences, the CV decreased as the FWHM value decreased. The differences of mean signal intensities between subcortical and deep white matter also decreased with smaller FWHM values. The contrast between white and gray matter was maintained at all FWHM values. LSA length was significantly greater in corrected MIP than in the original MIP images. CONCLUSIONS: Intensity inhomogeneity in 7T MRI can be successfully corrected using SPM8 for various scan sequences.
PURPOSE: To evaluate the performance and efficacy for intensity inhomogeneity correction of various sequences of the human brain in 7T MRI using the extended version of the unified segmentation algorithm. MATERIALS: Ten healthy volunteers were scanned with four different sequences (2D spin echo [SE], 3D fast SE, 2D fast spoiled gradient echo, and 3D time-of-flight) by using a 7T MRI system. Intensity inhomogeneity correction was performed using the "New Segment" module in SPM8 with four different values (120, 90, 60, and 30 mm) of full width at half maximum (FWHM) in Gaussian smoothness. The uniformity in signals in the entire white matter was evaluated using the coefficient of variation (CV); mean signal intensities between the subcortical and deep white matter were compared, and contrast between subcortical white matter and gray matter was measured. The length of the lenticulostriate (LSA) was measured on maximum intensity projection (MIP) images in the original and corrected images. RESULTS: In all sequences, the CV decreased as the FWHM value decreased. The differences of mean signal intensities between subcortical and deep white matter also decreased with smaller FWHM values. The contrast between white and gray matter was maintained at all FWHM values. LSA length was significantly greater in corrected MIP than in the original MIP images. CONCLUSIONS: Intensity inhomogeneity in 7T MRI can be successfully corrected using SPM8 for various scan sequences.
Authors: Qiyuan Tian; Berkin Bilgic; Qiuyun Fan; Chanon Ngamsombat; Natalia Zaretskaya; Nina E Fultz; Ned A Ohringer; Akshay S Chaudhari; Yuxin Hu; Thomas Witzel; Kawin Setsompop; Jonathan R Polimeni; Susie Y Huang Journal: Cereb Cortex Date: 2021-01-01 Impact factor: 5.357
Authors: Qiyuan Tian; Qiuyun Fan; Thomas Witzel; Maya N Polackal; Ned A Ohringer; Chanon Ngamsombat; Andrew W Russo; Natalya Machado; Kristina Brewer; Fuyixue Wang; Kawin Setsompop; Jonathan R Polimeni; Boris Keil; Lawrence L Wald; Bruce R Rosen; Eric C Klawiter; Aapo Nummenmaa; Susie Y Huang Journal: Sci Data Date: 2022-01-18 Impact factor: 6.444