TVM evaluation in a phantom. (a) Phantom and experimental setup. [(b)–(f)]1: Volume rendering showing an outlined target (red), bone, and color coded TVM. Regions encompassing prostate, rectum, and bladder were outlined as targets on CT. 3. As in 1 with US probe in a recorded imaging position. 2 and 4. US volume fused with the phantom CT. The US volume is acquired with the US probe in the imaging position depicted in 2. [(g)–(l)]1: Volume rendering showing an outlined target (red), bone, color coded TVM, and US probe in recorded imaging position. 2 and 3. US volume fused with the phantom CT. The US volume is acquired with the US probe in the imaging position depicted in 1.