The role of the defaecating pouchogram in the assessment of evacuation difficulty after restorative proctocolectomy and pouch-anal anastomosis.

Abstract

Restorative proctocolectomy (RPC) with ileal pouch-anal anastomosis (IPAA) is the most frequently performed operation for intractable ulcerative colitis (UC) and for many patients with familial adenomatous polyposis (FAP). It can be complicated by a functional evacuation difficulty, which is not well understood. We aimed to evaluate the role of defaecating pouchography in an attempt to assess the mechanism of evacuation difficulty in pouch patients. All RPC patients who had had a defaecating pouchogram for evacuation difficulty at one hospital between 2006 and 2014 were retrospectively reviewed. The findings and features were correlated with the symptoms. Demographic, clinical and radiological variables were analysed. Eighty-seven [55 (63%) female] patients aged 47.6±12.5years (mean standard±SD) were identified. Thirty-five had a mechanical outlet obstruction and 52 had no identified mechanical cause to explain the evacuation difficulty. The mean age of these 52 [33 (63%) female] patients was 48.2±13years. Of these 52 patients, significantly more used anti-diarrhoeal medication (P=0.029), complained of a high frequency of defaecation (P=0.005), experienced a longer time to the initiation of defaecation (P=0.049) and underwent pouchoscopy (P=0.003). Biofeedback appeared to improve the symptoms in 7 of 16 patients with a nonmechanical defaecatory difficulty. The most common findings on defaecating pouchography included residual barium of more than 33% after an attempted evacuation (46%, n=24), slow evacuation (35%, n=18) and mucosal irregularity (33%, n=17). Correlation between radiological features and symptoms showed a statistically significant relationship between straining, anal pain, incontinence and urgency with patterns of anismus or pelvic floor descent or weakness seen on the defaecating pouchogram. Symptoms of incomplete evacuation, difficulty in the initiation of defaecation, high defaecatory frequency and abdominal pain were not correlated with the radiological features of the pouchogram. Defaecating pouchography may be useful for identifying anismus and pelvic floor disorders in pouch patients who have symptoms of straining, anal pain or incontinence. In patients with a high frequency of defaecation and abdominal pain it does not provide clinically meaningful information. Patients who complain of straining, incontinence, anal pain or urgency and have anismus or pelvic floor disorders may benefit from behavioural therapy.