[Evacuation defecography and defecoflometry in diagnosis of chronic constipation. A prospective comparative study of 49 patients].

Chronic constipation can be divided in two large groups: slow-transit constipation, caused by pathological intestinal transit, and obstructive defecation disorder, caused by pelvic and rectal wall abnormalities. Videodefecography and defecoflowmetry are methods used to study dynamic evacuation of the rectum. Videodefecography also enables visual estimation of rectal evacuation. Defecoflowmetry allows analysis of anal and rectal pressures. Within this prospective study we utilized and compared these methods in 19 patients with slow transit and 30 patients with obstructive disease. In patients with slow transit, both investigations demonstrated a significantly higher defecation rate than in obstructive defecation disorder (slow transit: defecoflowmetry 65%, videodefecography 80%; obstructive defecation disorder: 50% and 58%). The evacuation time was pathologically prolonged in both types of constipation, with a range of 43-55 s. Rectoceles are demonstrated in 94% of cases with slow transit and in 72% with obstructive defecation disorder. Also, we often found obstructive components in slow-transit constipation patients. Normal defecography or defecoflowmetry can rule out obstructive defecation disorder. We conclude that videodefecography and defecoflowmetry are important items in the complex diagnostic regimen needed in evaluation of chronic constipation.