Categorization and anorectal manometry in chronic constipation

Objective We categorized chronic constipation according to colonic transit time (CTT) and transit index (TI), and investigated the abnormalities of anorectal motility and sensory function in patients in different categories. Methods Each subject ingested 20 radiopaque markers, and abdominal X rays were obtained at 72 h. Chronic constipation was categorized according to CTT and TI. Anorectal manometry was carried out in all subjects to investigate the abnormalities of anorectal motility and sensory function in patients in different categories. Results Chronic constipation was divided into four types: normal transit constipation (NTC), slow transit constipation (STC), outlet obstructive constipation (OOC), and mixed type constipation (MC). Patients with constipation displayed significantly lower anorectal resting pressure, squeezing pressure and larger rectal maximum tolerate volume than controls ( P 0.05). Compared with controls, NTC displayed significantly lower anorectal resting pressure ( P 0.05) while STC displayed significantly lower anorectal resting pressure and squeezing pressure ( P 0.05). The rectal maximum tolerate volume in STC and OOC was significantly higher than that of controls ( P 0.05). Conclusion It is a simple method to take abdominal X rays at 72 h after ingesting 20 radiopaque markers. Categorization of constipation according to CTT and TI can be an indicator of the dynamic etiology of constipation. Patients with constipation in different categories had different abnormalities of anorectal dynamics and sensory function.