Abstract
To demonstrate the pelvic peritoneal recesses during voiding, evacuation proctography was combined with positive contrast peritoneography. In 30 constipated patients, peritoneography was performed, followed by proctography. During evacuation rectogenital herniation developed in 20 patients (66%), without visceral filling in 12 (40%). Posterior pelvic floor hernia is common during defecation. Less than half fill with bowel and many may not be apparent on standard proctography.