[Simplified defecography technique. Description and results].

Defecography is a useful paraclinical examination to explore disturbances of continence or defecation. The purpose of this study was to present a simplified defecography technique and assess its validity in subjects without defecation problems (n = 10) and in patients complaining of idiopathic chronic constipation (n = 35). The anorectal angle at rest (RAA) and when straining at stool was not significantly different in constipated patients and in controls. Defecography often gave abnormal results. Anterior rectocele was found in almost 50 percent (17/35) of constipated patients and in 20 percent (2/10) of controls (P less than 0.05). None of the patients had posterior rectocele. Persistent imprint of the puborectal muscle during straining was present in 36 percent (9/35) of constipated patients and in 10 percent (1/10) of controls (NS). The imprint was not always associated with closure of the RAA between rest and straining; this closure was never found in controls but was observed in 6 out of 17 constipated patients (35 percent; P less than 0.05). Perineal descent (PD) varied from 0.6 to 3.7 cm (mean +/- s.e.m.: 2.0 +/- 0.63 cm) in controls, as against 0.6 to 7.9 cm (mean +/- s.e.m.: 2.7 +/- 0.45 cm) in constipated patients. In 24 percent of the constipated patients PD was greater than 3.7 cm (the maximum value recorded in controls). All constipated patients with closure of the RAA during defecation had a PD of less than 1 cm, thus confirming the concept of "pelvic floor muscle hypertonia". Disorders of rectal statics are more frequent in subjects with constipation, but their significance is varied. Some abnormalities could be the cause of constipation (e.g. anismus) and others its consequence (anterior rectal prolapse, anterior rectocele, PD).