直肠系膜两个无血管层次的解剖特征

目的：探讨全直肠系膜切除的解剖学基础，明确全直肠系膜切除的切除平面。方法：对23具尸体的盆腔进行解剖，观察直肠系膜与周围筋膜、神经的关系。结果：在直肠的侧后方存在两个无血管层次．即直肠周围脂肪与脏筋膜之间的层次及脏层筋膜与壁层筋膜之间的层次。各层次内存在不同的组织结构，在直肠与脏筋膜间存在着直肠侧韧带．在脏、壁层筋膜间存在着腹下神经和盆内脏神经。结论：全直肠系膜切除的切除范围应包括脏层筋膜在内，解剖层次应为脏、壁层筋膜间层次；术中通过观察两个无血管层次中的结构可以判定是否进入了正确的全直肠系膜切除的切除层次。

Anatomical characteristics of the two avascular planes of mesorectum

Objectives To clarify the anatomic basis of total mesorectal excision （TME） and to specify an appropriate dissection plane of TME. Methods Dissection of the pelvis was carried out in 23 cadavers （12 male, 11 female） in order to observe the relationship between the mesoreetum and its related fascias and the pelvic nerves. Results There were two avaseular planes latero-posteriody to the rectum, one laid between the perireetal fat and the visceral fascia, and the other one laid between the visceral and the parietal fascia. They could be identified according to the different structures they contained. The lateral rectal ligament was located between the rectum and the visceral fascia, and the pelvic splanehnic and hypogastric nerves were founded between the visceral and the parietal fascia. Conclusions The visceral fascia should be included in TME; the appropriate plane of dissection is between the visceral and the parietal fascia. The different structures in the two avascular planes could determine whether it is the correct plane that the surgeon is dealin~ with in peffonning TME.