Anorectal manometry (ARM) is a medical test used to measure pressures in the anus and rectum and to assess their function. The test is performed by inserting a catheter, that contains a probe embedded with pressure sensors, through the anus and into the rectum. Patients may be asked to perform certain maneuvers, such as coughing or attempting to defecate, to assess for pressure changes. Anorectal manometry is a safe and low risk procedure. From 2014 to 2018, the international anorectal physiology working group (IAPWG) meet several times to develop consensus on indications for anorectal manometry. Their assessment concluded that anorectal manometry was indicated when used in assessment of fecal incontinence, constipation, evacuation disorders (including Hirschsprung's disease), functional anorectal pain and in the assessment of anorectal function preoperatively or after a traumatic obstetric injury. In addition to the indications outlined by the IAPWG, anorectal manometry has been used as a component of anorectal biofeedback. Since its introduction in 2007, high resolution anorectal manometry (HR-ARM) has increasingly replaced conventional anorectal manometry as the standard. There has been increasing usage of high-definition (3D) anorectal manometry (HD-ARM) as well. Current advances in anorectal manometry include the development of bedside portable technology. Medical Uses Fecal Incontinence After eliminating structural causes of fecal incontinence from the differential diagnosis, anorectal manometry may be used to evaluate deficiencies in sphincter function or anorectal sensation. An abnormal resting pressure or squeeze pressure may indicate problems with either the internal anal sphincter or the external anal sphincter respectively. Both increased and decreased anorectal sensation has also been detected in individuals with fecal incontinence. The use of HD-ARM can allow recognition of pressure asymmetry within the anorectum. Some patients with fecal incontinence benefit from muscle strength training which may make use of anorectal biofeedback. Constipation Anorectal manometry can be used in the diagnostic workup of individuals with chronic constipation without a known cause or with chronic constipation that has not improved on a trial of laxatives and/or fiber. For example, on a digital rectal exam, a physician may notice specific findings that point to dyssynergic defecation, a cause of chronic constipation. In such instances, the physician may order an anorectal manometry study to verify their findings. Abnormal results, such as the presence of a paradoxical contraction of the anal sphincter muscles during defecation (i.e. the muscles are squeezing instead of relaxing), can also be used to guide treatment (e.g. anorectal biofeedback).