The changes in resting anal pressure after performing full-thickness rectal advancement flaps

Area of Science:

• Colorectal Surgery
• Gastroenterology
• Surgical Innovation

Background:

• Rectal advancement flap is a standard treatment for complex fistula-in-ano.
• Understanding the impact on anal canal pressure is vital for patient outcomes.

Purpose of the Study:

• To evaluate changes in anal canal resting pressure after a full-thickness rectal advancement flap.
• Assess the correlation between flap procedure and anal manometry.

Main Methods:

• Manometric analysis of patients undergoing rectal advancement flap for anal fistulas.
• Evaluation of recurrence and continence rates.
• Measurement of maximum resting pressure (MRP) and inferior resting pressure (IRP).

Main Results:

• 119 patients analyzed; 5.9% recurrence, 76.5% maintained continence.
• Significant decrease in postoperative MRP (90.6 to 45.2 mmHg, p < 0.001).
• No significant change in IRP (28.2 to 23.2 mmHg, p = 0.1).

Conclusions:

• Full-thickness rectal flaps decrease MRP, likely due to internal sphincter inclusion.
• Preserving the distal internal sphincter is key for maintaining lower anal canal pressure and avoiding deformities.