Male pelvic anatomy reconstructed from the visible human data set

Purpose: To improve understanding of the male pelvic anatomy pertinent to urological surgery we performed computer generated, 3-dimensional reconstruction of the male pelvis from the Visible Human data set. Materials and Methods: A total of 18 discrete anatomical structures, including the prostate, bladder, urethra, rectum and pelvic musculature, was segmented from the Visible Human cross-sectional data obtained from the National Library of Medicine. Using high speed computing and rendering software, S-dimensional models of each structure were generated and assembled into composite figures. Results: These reconstructions offer a revised view of pelvic anatomy as it has been traditionally depicted. The lateral surfaces of the levator ani muscle are oriented vertically in the pelvis and directly applied to the entire lateral surface of the prostate. The bladder rests primarily anterior to the prostate rather than directly above it, as has been commonly depicted. In the cross-sectional data and reconstructions the trigone and anterior fibromuscular stroma of the prostate appear as a single unit in continuity, which may have functional implications for understanding the mechanisms of continence at the bladder neck. The striated urethral sphincter appears circular with abundant tissue posteriorly. This sphincteric muscle has greater length anteriorly than posteriorly. Conclusions: These 3-dimensional reconstructions provide unique insights into male pelvic anatomy. They are a useful teaching tool for investigation and virtual reality modeling of the male pelvis.