Gastrointestinal manometry is a diagnostic procedure that measures pressure and muscle activity within the digestive tract. It provides insights into the function and coordination of the muscles and nerves that control food movement through the gastrointestinal (GI) system, helping understand the underlying causes of digestive symptoms.
What Gastrointestinal Manometry Measures
Gastrointestinal manometry uses a thin, flexible catheter with pressure sensors. This catheter is inserted into specific GI tract sections (esophagus, stomach, small intestine, or rectum) to capture data. The sensors detect pressure changes and transmit information to a computer for analysis.
The procedure measures muscle function, assessing the strength and coordination of peristalsis (wave-like contractions that propel contents). It also evaluates the relaxation and contraction of sphincters, muscular valves controlling food and waste flow. By recording these pressure dynamics, the test maps motor activity within the digestive tract.
Conditions Diagnosed by Manometry
Gastrointestinal manometry is employed when symptoms suggest a problem with how food moves through the digestive tract, particularly when structural issues have been ruled out. Common symptoms prompting this test include difficulty swallowing (dysphagia), persistent heartburn or acid reflux that does not respond to standard treatments, unexplained chest pain, severe nausea and vomiting, chronic constipation, or fecal incontinence.
Manometry identifies uncoordinated contractions, weak muscle function, or abnormal sphincter relaxation. Esophageal manometry diagnoses conditions like achalasia, where the lower esophageal sphincter fails to relax. Gastroduodenal manometry differentiates muscle and nerve disorders causing delayed gastric emptying, such as gastroparesis. Anorectal manometry assesses rectal and anal muscle strength and coordination, aiding in diagnosing conditions like pelvic floor dysfunction, which can cause chronic constipation or fecal incontinence.
Preparing For and Undergoing Manometry
Preparation for gastrointestinal manometry involves specific instructions. Patients typically fast for six to twelve hours before the test. Medications affecting gut motility, such as proton pump inhibitors, calcium channel blockers, or sedatives, may need adjustment under healthcare provider guidance.
During the procedure, a thin, flexible catheter is inserted. For esophageal or gastroduodenal manometry, it passes through the nose and throat into the esophagus, stomach, or small intestine; a numbing spray may be used. For anorectal manometry, the catheter is inserted through the anus.
Test duration varies: esophageal manometry often takes 30-40 minutes, while gastroduodenal can last 5-24 hours to monitor both fasting and fed states. Patients remain still and follow instructions, such as swallowing or bearing down, to record muscle activity. The procedure is generally well-tolerated, though mild discomfort like gagging or pressure is possible during insertion. Most individuals can resume normal activities and diet immediately afterward.
Interpreting Manometry Outcomes
After the procedure, specialists analyze the collected pressure data. Muscle activity and pressure readings are compared against normal ranges for the studied digestive tract part. This identifies abnormalities or dysfunctions in muscle contraction and sphincter relaxation.
The results provide information on the strength, coordination, and timing of muscle movements and sphincter function. For example, esophageal manometry identifies patterns like absent coordinated contractions or incomplete lower esophageal sphincter relaxation. Manometry results offer diagnostic insights, considered with other tests and clinical symptoms to guide treatment. A healthcare professional discusses findings and implications with the patient to determine next steps.