Improved geometric distortion in coronal diffusion-weighted and diffusion tensor imaging using a whole-brain isotropic-voxel acquisition technique at 3 Tesla.
OBJECTIVE
We used a whole-brain, isotropic-voxel acquisition technique to improve the geometric distortion in diffusion-weighted (DWI) and diffusion tensor imaging (DTI) in coronal directions, which is remarkable at high magnetic fields.


METHODS
We performed magnetic resonance imaging of 17 healthy volunteers using a 3T scanner and obtained coronal DWI/DTI as well as coronal images that were reformatted from isotropic volume data acquired by 1.6-mm-thick axial DWI/DTI. We visually evaluated the degree of image distortion and quantitated the findings by co-registration analysis.


RESULTS
In-plane geometric distortions in coronal DWI/DTI, particularly at the frontal base and medial temporal lobe, were dramatically diminished when the isotropic-voxel acquisition technique was used. Quantitative measurement revealed a reduction in areas of misregistration, but not their absence, in reformatted coronal images, mainly because of distortion in the anteroposterior direction in the source images.


CONCLUSIONS
The isotropic-voxel DWI/DTI technique enabled acquisition of coronal images that represented anatomical details accurately with permissible spatial distortion while maintaining spatial resolution, even at 3T.
Advanced Medical Research Center, Iwate Medical University, Takizawa, Iwate, Japan. shunfuji@iwate-med.ac.jp
Shunrou
S
Fujiwara
Makoto
M
Sasaki
Yoshiyuki
Y
Kanbara
Yutaka
Y
Matsumura
Eri
E
Shibata
Takashi
T
Inoue
Hideaki
H
Nishimoto
Akira
A
Ogawa
D000328:Adult; D000368:Aged; D016477:Artifacts; D001921:Brain / Q000033:anatomy & histology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D005625:Frontal Lobe / Q000033:anatomy & histology; D006624:Hippocampus / Q000033:anatomy & histology; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016548:Prosencephalon / Q000033:anatomy & histology; D013702:Temporal Lobe / Q000033:anatomy & histology