Transrectal US of the prostate (A) is used to identify suspicious areas and to perform systematic saturation biopsies. Note the cursor in (A) overlying a focal round nodule that was biopsied. The volume of the gland is automatically calculated using measurements of width, height, and depth applied to the formula of a prolate ellipse volume (height × length × width × π/6). Biopsies are performed using the 3D volumetric rendering of the gland (C and D) with mapped record of all passes into the prostate.