Adrenal tissue characterization with 0.5-T MR imaging: value of T2*-weighted images.
The authors investigated the value of magnetic resonance (MR) imaging at 0.5 T for distinguishing adrenal adenomas from adrenal metastases. The series included 23 adrenal adenomas (18 nonhyperfunctioning, five hyperfunctioning) and 23 adrenal metastases from various organs. Adrenal tumor-liver signal intensity ratios on T1-, T2-, and T2*-weighted images were calculated for adrenal tissue characterization. Adrenal adenomas were more precisely distinguished from adrenal metastases on T2*-weighted images (21 of 23, 91%) than on T2-weighted images (15 of 23, 65%). T1-weighted images were not useful for this distinction. In conclusion, T2*-weighted images were better than routine T2-weighted images for distinguishing adrenal adenomas from adrenal metastases. It can be postulated that the total signal intensity of adrenal adenomas, which contain some fat components, decreased on T2*-weighted images because of an out-of-phase effect.
Department of Radiology, Yamanashi Medical College, Japan.
T
T
Ichikawa
H
H
Fujimoto
K
K
Murakami
M
M
Tauchi
S
S
Mochizuki
K
K
Ohtomo
G
G
Uchiyama
D000236:Adenoma / Q000175:diagnosis; D000310:Adrenal Gland Neoplasms / Q000175:diagnosis* / Q000556:secondary; D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged