Perineal descent and levator ani hernia: a dynamic magnetic resonance imaging study

Patients with symptomatic pelvic organ prolapse often have multifocal pelvic floor defects that are not always evident of physical examination. In this study, dynamic magnetic resonance imaging of symptomatic patients with pelvic floor prolapse demonstrated unsuspected levator ani hernia. This study was designed to identify any specific symptoms and/or physical findings associated with these hernias.

Eighty consecutive patients with pelvic organ prolapse, fecal and/or urinary incontinence, or chronic constipation received standardized questionnaires, physical examination, and dynamic magnetic resonance imaging. Fisher's exact test was used to compare symptoms and examination findings between patients with or without levator ani hernia.

Twelve patients (15 percent) were found to have unilateral (n = 8) or bilateral (n = 4) levator ani hernias on dynamic magnetic resonance imaging. No one specific symptom was directly associated with the presence of a levator ani hernia. Furthermore, levator ani hernias were not found more frequently in patients with previous pelvic floor surgery. Perineal descent on physical examination was associated with the finding of a levator ani hernia in nine patients (P = 0.02). Although not statistically significant, there was a trend toward a lower incidence of levator ani hernia in females using estrogen replacement therapy (P = 0.06).

Patients with symptomatic pelvic organ prolapse and perineal descent on physical examination may have a levator ani hernia. Although the significance of levator ani hernia needs to be determined, the recurrence rate after the surgical management of pelvic organ prolapse remains unacceptably high, and ongoing investigation of all associated abnormalities is warranted.