Postsurgical spinal magnetic resonance imaging with iterative decomposition of water and fat with echo asymmetry and least-squares estimation.
OBJECTIVE
Magnetic resonance imaging (MRI) is the most popular follow-up study for patients who have undergone spinal surgery. However, the image quality often becomes poor because of artifacts from metal implants and/or from failed fat suppression, which obscure diagnosis. Iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) is a new fat suppression method that is less affected by inhomogeneity of the magnetic field. Here, we compared postsurgical spinal MRI with IDEAL versus chemical shift selective saturation (CHESS).


METHODS
For 35 patients who had spinal surgery, we examined T2-weighted fast spin-echo sagittal images of the spine with both IDEAL and CHESS. Two radiologists evaluated the degrees of fat suppression and spinal canal projection from 0 (least/worst) to 2 (most/best).


RESULTS
Fat suppression and spinal canal scores for IDEAL were statistically higher than those for CHESS (P < 0.05).


CONCLUSIONS
Iterative decomposition of water and fat with echo asymmetry and least-squares estimation is clinically useful for postoperative spinal MRI.
Department of Radiology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan. tanomizu@gmail.com
Mizuho
M
Murakami
Harushi
H
Mori
Akira
A
Kunimatsu
Osamu
O
Abe
Hirotaka
H
Chikuda
Takashi
T
Ono
Hiroyuki
H
Kabasawa
Kazuyuki
K
Uchiumi
Jiro
J
Sato
Shiori
S
Amemiya
Shuhei
S
Komatsu
Kuni
K
Ohtomo
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D016268:Internal Fixators; D016018:Least-Squares Analysis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis*; D013122:Spinal Diseases / Q000601:surgery*; D018709:Statistics, Nonparametric