title: Prostatic disorders: MR imaging at 1.5 T.
abstract: Pelvic magnetic resonance (MR) images obtained at 1.5 T of 31 men with known genitourinary disease were reviewed retrospectively. In most, peripheral and central prostatic zones could be seen on axial images obtained with long repetition times/echo times (TRs/TEs). The prostate had no specific signal intensity that enabled differentiation between benign and malignant changes. Each patient with known extracapsular prostatic carcinoma had a peripheral zone defect--1 cm or greater in diameter with ill-defined borders and relatively lower signal intensity than that of the remainder of the peripheral zone--that correlated with the site of clinical-pathologic involvement. Correlation of a peripheral zone defect on long TR/TE images as a sign for extracapsular spread of prostatic cancer was 100% sensitive, yet 54% specific, with excellent interobserver agreement. Stage A2 and B1 prostatic carcinoma was not detected. Benign prostatic hyperplasia was seen as centrally located proliferation and nodularity, usually with discrete margins and a wide spectrum of low- to high-signal-intensity features. MR imaging may have a role in differentiating between intracapsular and extracapsular prostatic carcinoma.
mesh_terms: D000328:Adult; D000368:Aged; D006801:Humans; D008207:Lymphatic Metastasis; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology*; D011469:Prostatic Diseases / Q000175:diagnosis*; D011470:Prostatic Hyperplasia / Q000175:diagnosis; D011471:Prostatic Neoplasms / Q000175:diagnosis; D012189:Retrospective Studies; D012669:Seminal Vesicles / Q000473:pathology; D014515:Ureteral Diseases / Q000175:diagnosis; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis