What is benign prostatic hyperplasia (BPH), and what are its cross sectional imaging features?
BPH is an aging phenomenon in the prostate gland, seen in up to 90% of men of advanced age. It is caused by enlargement of the transitional zone.
On cross-sectional imaging, heterogeneous nodular enlargement of the central gland is seen, leading to overall enlargement of the prostate gland. The enlarged central gland is hypoechoic on US and has increased attenuation and enhancement on CT. On T2-weighted MR images, glandular and cystic foci of BPH have high signal intensity, whereas stromal-dominant foci of BPH have low signal intensity. There may be associated compression of the peripheral zone, extension into the peripheral zone, mass effect upon the bladder base, or findings of chronic bladder outlet obstruction such as bladder wall thickening, trabeculation, or diverticulum formation