Internal rectal intussusception--fact or fancy?

There is still considerable debate whether internal intussusception represents a functional disorder. We have reviewed our results in an effort to define its symptomatology and to assess defecography.

Rectopexy has been performed for internal intussusception in 37 patients. Eighteen had solitary rectal ulcer syndrome (SRUS), and 31 had anterior rectal wall prolapse. Defecography demonstrated anterior wall prolapse in 13, circular prolapse in 21, and no disorders in 3 patients. Pelvic floor function was normal. Follow-up varied from one to nine years.

Twenty-six patients became asymptomatic. Anterior wall prolapses could not be palpated anymore. All SRUS lesions healed. Patients with SRUS (P < 0.001) or circular prolapse (P < 0.001) became significantly more asymptomatic. Results in patients with anterior rectal wall prolapse were significantly worse (P < 0.001).

Internal intussusception is a distinct functional rectal disorder. Its symptomatology and findings during physical examination are aspecific. Characteristic defecographic features and presence of SRUS are indications for surgery, provided pelvic floor function during straining is normal.