Three-dimensional susceptibility-weighted imaging at 3 T using various image analysis methods in the estimation of grading intracranial gliomas.
OBJECTIVE
Although three-dimensional (3D), high-spatial resolution susceptibility-weighted imaging (SWI) appears to be valuable in the evaluation of central nervous system gliomas, several evaluation methods are proposed in the literature. The purpose of this study was to evaluate the use of 3D SWI for grading intracranial gliomas with various analysis methods.


METHODS
Twenty-three patients suspected of having gliomas participated in this study. SWI was performed in addition to conventional MR sequences. In 15 cases, post-gadolinium enhanced SWI was also obtained. Imaging evaluation criteria were conventional grade, hypointensity ratio in the tumor-dominant structure of hypointensity on SWI (hemorrhage or vascular structure) and presence of abnormal enhancement surrounding the tumor.


RESULTS
Mean grading scores of conventional grade showed no statistically significant difference among WHO grades. Mean grading scores of hypointensity ratios in the tumor were higher for WHO Grades 3 and 4 than for lower grade tumors (P=.05, Mann-Whitney U test). Hemorrhagic foci were more frequently seen in the higher grade tumor. Post-contrast susceptibility-weighted images of five of 11 WHO Grade 3 and 4 cases showed bright enhancement surrounding the tumor, suggesting a breakdown of the blood-brain barrier.


CONCLUSIONS
SWI at 3 T may be a useful method to analyze the structural characteristics of gliomas and to evaluate pathology in vivo. Assessment of hypointensity ratios in the glioma was the most preferable method in grading glioma. However, more studies, specifically concerning a suitable method for image analysis, are needed to establish SWI at 3 T as a useful tool in clinical routine.
Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuou, Yamanashi, 409-3898, Japan. masahori@yamanashi.ac.jp
Masaaki
M
Hori
Harushi
H
Mori
Shigeki
S
Aoki
Osamu
O
Abe
Tomohiko
T
Masumoto
Satoshi
S
Kunimatsu
Kuni
K
Ohtomo
Hiroyuki
H
Kabasawa
Nobuyuki
N
Shiraga
Tsutomu
T
Araki
D000328:Adult; D001812:Blood-Brain Barrier / Q000473:pathology; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000098:blood supply* / Q000473:pathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D003287:Contrast Media / Q000494:pharmacology*; D005260:Female; D005910:Glioma / Q000098:blood supply* / Q000473:pathology; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D009367:Neoplasm Staging / Q000379:methods
D003287:Contrast Media