Description

Chronic intractable constipation and faecal incontinence are highly prevalent functional colorectal disorders afflicting approximately 3% of the general population. The individual sufferer may complain of incapacitating symptoms, associated with a debilitating effect on quality of life, and these problems constitute a huge socio-economic burden. In those patients who warrant specialist investigation, assessment should be carried out in the context of a global evaluation, aimed at both morphology / anatomy and function. With advances in diagnostic technology, a number of complementary tests now exist which should be carried out in a structured and comprehensive manner to address all understood and measurable components which may contribute to the presenting disorder(s). This review covers imaging modalities and tests of physiological function that are available for the clinical assessment of the large bowel in such patients. In those with constipation, colonic transit studies, tests of rectal evacuation and assessment of rectal sensation are primarily indicated. In patients suffering from severe faecal incontinence, tests of both anal sphincter function (anal manometry, endo-anal ultrasound, and evaluation of pudendal nerve function) and rectal ‘reservoir’ function (sensory tests and Barostat assessment) are equally important. Nevertheless, it is essential to remember that symptom complexes overlap, and constipation and incontinence frequently co-exist.