Intensity inhomogeneity correction for magnetic resonance imaging of human brain at 7T. Issue 2 (14th January 2014)

• Record Type: Journal Article
• Authors: Uwano, Ikuko; Kudo, Kohsuke; Yamashita, Fumio; Goodwin, Jonathan; Higuchi, Satomi; Ito, Kenji; Harada, Taisuke; Ogawa, Akira; Sasaki, Makoto
• Is Part Of: Medical physics. Volume 41:Issue 2(2014)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2014-01-14
• Subjects: Magnetic resonance imaging -- MRI: anatomic, functional, spectral, diffusion -- Segmentation -- Smoothing -- Applied neuroscience; biomedical MRI -- brain -- Gaussian distribution -- image segmentation -- image sequences -- medical image processing -- smoothing methods; 7T -- MRI -- intensity inhomogeneity correction; Involving electronic [emr] or nuclear [nmr] magnetic resonance, e.g. magnetic resonance imaging -- Digital computing or data processing equipment or methods, specially adapted for specific applications -- Image data processing or generation, in general; Medical imaging -- Brain -- Magnetic resonance imaging -- Three dimensional image processing -- Medical image contrast -- Sequence analysis -- Medical image segmentation -- Vascular system -- Medical magnetic resonance imaging -- Medical image spatial resolution; Medical physics -- Periodicals; Medical physics; Geneeskunde; Natuurkunde; Toepassingen; Biophysics; Periodicals; Periodicals; Electronic journals; 610.153
• DOI: 10.1118/1.4860954
• Languages: English
• ISSNs: 0094-2405

Abstract

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.