Question

With reference to automatic nerve preservation during rectal Cancer surgery:
Anatomy and significance of relevant autonomic nerves and plexi in rectal cancer surgery.

Hint:

Preserving autonomic nerves during rectal cancer surgery is crucial to maintain bowel function and prevent complications such as incontinence and sexual dysfunction.

Answer 1

The autonomic nervous system plays a crucial role in regulating the function of the rectum and associated structures, such as the sphincters and the anal canal. During rectal cancer surgery, preserving these nerves is essential to avoid postoperative complications such as incontinence, sexual dysfunction, or impaired bowel motility.
Step 1: Anatomy of Relevant Autonomic Nerves and Plexi:
- Pelvic Splanchnic Nerves (S2-S4): These nerves are part of the parasympathetic nervous system and innervate the rectum, distal colon, and the internal anal sphincter. They are responsible for stimulating peristalsis and regulating the tone of the internal anal sphincter.
- Hypogastric Nerve (T10-L2): The hypogastric nerve is part of the sympathetic nervous system and supplies the rectum. It is involved in inhibiting peristalsis and contracting the internal anal sphincter.
- Pelvic Plexus: This plexus, located within the pelvic cavity, contains both sympathetic and parasympathetic fibers. It is involved in the regulation of blood flow to the rectum and the functioning of the internal anal sphincter.
- Inferior Mesenteric Plexus: This plexus provides autonomic innervation to the colon and rectum, influencing motility and vasomotor control.
Step 2: Significance of Nerve Preservation:
- Prevention of Incontinence: Damage to the pelvic splanchnic nerves can result in impaired bowel motility, leading to fecal incontinence. The preservation of these nerves during rectal cancer surgery is essential for maintaining normal bowel function.
- Sexual Function: The pelvic nerves also play a role in sexual function, and injury to these nerves can result in erectile dysfunction in men and vaginal dysfunction in women.
- Sphincter Control: The integrity of the hypogastric nerve and pelvic plexus is vital for maintaining the tone and function of the internal anal sphincter, preventing leakage and incontinence post-surgery.