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.
Fujiwara
Shunrou
S
Advanced Medical Research Center, Iwate Medical University, Takizawa, Iwate, Japan. shunfuji@iwate-med.ac.jp
Sasaki
Makoto
M
Kanbara
Yoshiyuki
Y
Matsumura
Yutaka
Y
Shibata
Eri
E
Inoue
Takashi
T
Nishimoto
Hideaki
H
Ogawa
Akira
A
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