Evaluation of the prostate by magnetic resonance imaging.

Forty-seven male patients with suspected prostatic disease underwent magnetic resonance imaging (MRI) of the pelvis on a Picker resistive magnet operating at 0.15 T; 33 had histologically proved adenocarcinoma, 12 benign prostatic hypertrophy, 1 a transitional cell carcinoma, and 1 a seminoma. Eleven normal subjects also were included in the study. The study attempted to (1) define the MRI characteristics of the normal prostate, benign prostatic hypertrophy, and prostatic adenocarcinoma, (2) evaluate various pulse sequences in imaging the prostate, and (3) compare MRI findings with clinical, pathologic, and computed tomography results. Various pulse sequences, including inversion recovery and spin-echo with short and long TE and TR, were used. MRI was sensitive in detecting intracapsular and extracapsular prostatic disease. The finding of inhomogeneous signal texture throughout the gland was a sensitive but nonspecific finding for adenocarcinoma. A focal nodule with prolonged T1 and T2 relaxation times was the most specific MRI finding for adenocarcinoma. Extracapsular spread of neoplasm was often demonstrated, and because of its superior soft-tissue contrast ability, MRI was more accurate than computed tomography in delineating extracapsular extension.