To perform a prostatectomy, a directionally illuminating balloon catheter enters a bladder. The catheter has a multi-lumen shaft. The balloon defines an interior fluidically connected to a balloon inflation lumen and is inflated therethrough. The balloon comprises a light source, a light-radiating surface adjacent the shaft-balloon junction, and a substantially opaque surface disposed at a portion of the balloon other than the light-radiating surface such that the integrated light source illuminates a proximal half of the environment outside the balloon. The balloon is inflated while in the bladder. Light from the light source is directed out through the light-radiating surface to illuminate at least a portion of a procedure area at the bladder-prostate junction. With the light illuminating the portion of the procedure area, at least a portion of a prostatectomy is performed at the portion of the procedure area.