What is Esophageal Manometry
Esophageal manometry is a diagnostic test that measures the pressure profiles of the esophageal sphincters and esophageal body muscle to evaluate esophageal motor function and diagnose motility disorders. 1
Technical Description
Esophageal manometry works by inserting a pressure-sensing catheter through the nose into the esophagus to measure:
- Lower esophageal sphincter (LOS) pressure and relaxation
- Upper esophageal sphincter function
- Esophageal body contraction amplitude
- Peristaltic sequence and coordination 2, 3
The test uses either water-perfused or solid-state catheters connected to recording devices that capture pressure data as the patient performs swallows 1.
Two Main Types of Equipment
Standard Manometry (SM)
- Uses 3-8 pressure sensors spaced along the catheter
- Requires a "pull-through" technique to map the LOS
- More operator-dependent interpretation 1
High Resolution Manometry (HRM)
- Uses up to 36 pressure sensors for simultaneous measurement across the entire esophagus
- Creates topographical pressure plots (2D and 3D contour maps)
- Superior to standard manometry in reproducibility, speed, and ease of interpretation 1
- Allows for objective metrics and pattern recognition using the Chicago Classification system 4, 5
Primary Clinical Indications
Esophageal manometry is indicated for:
Evaluating dysphagia when mechanical obstruction has been ruled out - particularly critical for diagnosing achalasia 6
Localizing the LOS before pH probe placement for reflux monitoring 1
Preoperative assessment before antireflux surgery to rule out achalasia and major motility disorders like diffuse esophageal spasm 1, 6
Subtyping achalasia - HRM identifies achalasia subtypes (I, II, III) which predict treatment outcomes, with Type II responding best to therapy 1
Diagnosing major motility disorders including diffuse esophageal spasm, hypercontractile esophagus, and absent peristalsis 1
Patient Preparation Requirements
Patients must:
- Fast for 6 hours before the test (12 hours if achalasia suspected with retained food at endoscopy) 1
- Undergo endoscopy with biopsies before manometry to exclude structural causes of dysphagia 1
- Stop medications affecting esophageal motility (nitrates, calcium channel blockers) for 48 hours if possible 1
Important caveat: Patients on anticoagulants (warfarin, DOACs) or antiplatelets (clopidogrel) have increased nosebleed risk during catheter insertion, though no formal recommendation exists to discontinue these medications 1.
What Manometry Does NOT Diagnose
Manometry is NOT indicated for:
- Diagnosing or confirming gastroesophageal reflux disease (GERD) 6
- Initial evaluation of chest pain due to low specificity 6
The test specifically evaluates motor function, not acid exposure or mucosal disease.
Clinical Impact
HRM with impedance can visualize bolus movement and assess peristaltic effectiveness, though its impact on therapeutic decision-making remains under investigation 1. For rumination syndrome, HRM with impedance after a test meal can provide diagnostic confirmation when clinical diagnosis is unclear 1.