RESUMEN
<p><b>OBJECTIVE</b>To study the relationship of mesorectum with fasciae and nerves in the pelvic cavity and to specify the proper planes of dissection in total mesorectal excision.</p><p><b>METHODS</b>Twenty-four pelvises (12 males and 12 females) harvested from cadavers were studied by dissection.</p><p><b>RESULTS</b>There were three planes surrounding the rectum as the visceral fascia, vesicohypogastric fascia and parietal fascia. The pelvic plexus and its branches situated between the visceral fascia and the vesicohypogastric fascia. Pelvic splanchnic nerves and hypogastric nerves were observed between the visceral fascia and the parietal fascia.</p><p><b>CONCLUSIONS</b>The posterior plane of total mesorectal excision lies between the visceral fascia and the parietal fascia. The lateral dissection should be conducted in a plane between the visceral fascia and the vesicohypogastric fascia. The proper planes for posterior and lateral resection can be identified by the hypogastric nerve and the pelvic plexus respectively.</p>