Is the volume retained after defecation a valuable parameter at defecography?

Area of Science:

• Gastroenterology
• Colorectal Surgery
• Radiology

Background:

• Incomplete rectal emptying is a common patient complaint.
• Defecography is a key imaging modality for evaluating anorectal function.
• The relationship between defecographic findings and the sensation of incomplete emptying requires further clarification.

Purpose of the Study:

• To correlate retained barium volume on defecography with specific defecographic findings.
• To investigate the relationship between retained volume and the subjective sense of incomplete evacuation.
• To determine if anorectal manometry parameters correlate with the sensation of incomplete emptying.

Main Methods:

• Analysis of 170 defecographic series.
• Planimetric estimation of retained barium volume.
• Correlation with defecographic findings, patient-reported incomplete emptying, and anorectal manometry data.

Main Results:

• No specific defecographic finding was associated with a higher or lower retained barium volume.
• The sense of incomplete evacuation did not correlate with the amount of retained barium.
• Anorectal manometry thresholds for urge and perception did not differ between patients with or without the sensation of incomplete emptying.
• Rectocele and internal prolapse localized retained volume to the lower rectum.
• Intussusception localized retained volume to the middle or upper rectum.

Conclusions:

• Defecographic findings generally do not explain the amount of retained volume or the sensation of incomplete emptying.
• Specific defecographic findings, such as rectocele or intussusception, can influence the location of retained barium.
• The subjective feeling of incomplete emptying may not be directly explained by objective defecographic measurements.