Anorectal Manometry Alone Is Ineffective for Diagnosing Dyssynergic Defecation

Dyssynergic defecation is a mechanism of functional constipation and is commonly diagnosed by anorectal manometry or evacuation proctography.

In the current study, three expert observers read anorectal manometry results from 85 women with functional constipation and 85 age-matched asymptomatic healthy volunteers. Pressure profiles were characterized as normal or one of the four types of dyssynergia.

Only 13% of the healthy volunteers had a normal pattern of rectal contraction and sphincter relaxation with simulated defecation. Type I dyssynergia (paradoxical anal contraction with increased rectal contraction pressure and increased sphincter pressure) was more common in volunteers compared with constipated patients (37% vs. 20%; P=0.03). Combi…