Rectal Distension Increased the Rectoanal Gradient in Patients with Normal Rectal Sensory Function

Area of Science:

• Gastroenterology
• Physiology

Background:

• Anorectal manometry is crucial for diagnosing functional defecatory disorders.
• Abnormal manometric patterns (dyssynergia) are frequently observed, necessitating method reassessment.
• The impact of rectal distension on anorectal pressure during simulated evacuation is unknown.

Purpose of the Study:

• To investigate the effect of rectal distension on anorectal pressure profiles.
• To determine if rectal distension enhances diagnostic value in functional defecatory disorders.
• To assess the influence on rectoanal gradient and dyssynergia during simulated evacuation.

Main Methods:

• 108 patients with chronic constipation underwent high-resolution anorectal manometry.
• Simulated evacuation was performed with an empty balloon and then with 50 and 100 ml distension.
• Subgroup analysis included balloon expulsion test (BET) outcomes and rectal sensory function.

Main Results:

• Rectal balloon distension improved rectoanal gradient and reduced dyssynergia.
• These improvements were significant only in patients with normal BET and rectal sensory function.
• Rectoanal gradient, BMI, and maximum tolerable volumes predicted BET results.

Conclusions:

• Rectal distension during simulated evacuation alters anorectal pressure profiles.
• Improvements in rectoanal gradient and dyssynergia are primarily seen in patients with normal rectal function and BET.
• This technique may refine diagnostic accuracy for specific patient subgroups.