Neurovascular quantitative study of the uterosacral ligament related to nerve-sparing radical hysterectomy

Objective: To analyze the distribution of autonomic nerves and blood and lymphatic vessels in the uterosacral ligament, elucidate detailed anatomy at a surgical level and provide pathobiological evidence for improvement of nerve-sparing radical hysterectomy.

Study design: Surgical samples were collected from 15 patients who underwent radical hysterectomy for early stage cervical cancer (FIGO Ib1-IIa). Twenty-nine fresh specimens were divided into cervical, intermediate and sacral sections, and then subdivided into superficial and deep portions from the middle: the medial surface and lateral surface were also subdivided in order to analyze lymphatic vessels. The numbers of nerve branches in each section or portion of the section were analyzed. The lengths of the uterosacral ligaments were measured and immunohistochemistry staining was studied. Autonomic nerves, blood vessels and lymphatic vessels were quantitatively analyzed using image analysis software and biological stereology.

Results: The volume density of sympathetic nerves in the deep portion was significantly higher than in the superficial portion (p<0.05), and the number of nerves was greatest in the cervical section (p<0.05). The volume density of blood vessels was not significantly different between the two portions (p>0.05) or among the three sections (p>0.05), and the volume density of the lymphatic vessels was greater in the medial surface (p<0.05), with most of them in the cervical section (p<0.05).

Conclusions: Our study provides systematic mapping of the location and distribution of autonomic nerve branches, blood vessels and lymphatic vessels in the uterosacral ligament.