[Recognition of surgical anatomy for intersphincteric resection]

Area of Science:

• Colorectal Surgery
• Surgical Anatomy
• Gastrointestinal Oncology

Background:

• Intersphincteric resection (ISR) is a surgical procedure requiring detailed knowledge of the anal canal anatomy.
• Key structures include the hiatal ligament, internal and external sphincters, and conjoined longitudinal muscle.

Purpose of the Study:

• To elucidate the specific anatomical structures involved in Intersphincteric Resection (ISR).
• To highlight the anatomical variations relevant to surgical planning and execution of ISR.

Main Methods:

• Detailed anatomical description of the hiatal ligament, internal sphincter, external sphincter, and conjoined longitudinal muscle.
• Comparison of anal canal structures with rectal anatomy.

Main Results:

• The hiatal ligament is a rectal longitudinal muscle branch attached to the levator ani.
• The internal sphincter originates at the hiatal ligament level, with variable distance to the dentate line.
• The conjoined longitudinal muscle extends to the anococcygeal ligament, aiding defecation.

Conclusions:

• Individual anatomical variations in the ISR field significantly impact surgical procedures.
• Precise understanding of these anatomical differences is essential for optimizing surgical techniques and anastomosis in ISR.