On this page
At a glance
- A thin catheter through the nose measures pressure along the esophagus while you take small sips.
- It diagnoses motility disorders such as achalasia, which can mimic reflux.
- It shows whether the esophagus is strong enough for a given type of anti-reflux procedure.
- Results are classified using the Chicago Classification, currently version 4.0.
What manometry measures
The catheter has many closely spaced pressure sensors, producing a color map of each swallow from the throat to the stomach. It shows:
- Whether the lower esophageal sphincter relaxes properly when you swallow — it doesn’t in achalasia
- The strength and coordination of the squeezing wave that carries food down
- Premature or spastic contractions, which can cause chest pain and food sticking
- The location of the valve and any hiatal hernia, which is also used to position a pH-impedance catheter
Why it matters before reflux surgery
A fundoplication, LINX, or TIF adds resistance at the bottom of the esophagus. If the esophagus squeezes weakly or not at all — or if the real problem is achalasia — that added resistance can cause serious swallowing difficulty. The ACG guideline recommends manometry before anti-reflux surgery or endoscopic therapy to exclude achalasia and absent contractility, and the AGA lists assessment of esophageal function as part of confirming someone is a candidate.
Results can also influence the type of procedure — for example, whether a partial wrap may be a better match than a complete wrap. See how swallowing function affects treatment decisions.
What the test is like
After a numbing gel or spray, the catheter is passed through the nose into the esophagus while you swallow. You’ll then take a series of small sips of water, sometimes in more than one position and sometimes with a few rapid swallows or a small amount of solid food, as the current Chicago Classification protocol recommends. The measurement portion usually takes a short time. There’s no sedation, so you can drive yourself and return to normal activity afterward.
Most people describe the placement as briefly unpleasant — watery eyes, a gagging feeling — and then tolerable.
Preparing
You’ll typically be asked not to eat for several hours beforehand. Some medications affect esophageal muscle, so bring a complete medication list and follow the instructions given by the testing team.
Common questions
What happens during esophageal manometry?
After numbing the nose, a thin catheter is passed into the esophagus and you take a series of small sips of water while pressure sensors record each swallow; there’s no sedation, and you can drive afterward.
Placement is the hardest part — expect a gagging feeling and watery eyes for a moment as you swallow the catheter down. Once it’s in position, most people settle quickly. You’ll lie or sit and take small sips on instruction, and you may be asked to take several rapid swallows or a small amount of solid food, because these challenges reveal problems that single sips can miss.
When the test is finished, the catheter is removed and you can eat and go about your day. Your results are interpreted using a standardized system (the Chicago Classification) and shared with the clinician who ordered the test.
Sources
- Yadlapati R, et al. Esophageal motility disorders on high-resolution manometry — Chicago classification version 4.0. Neurogastroenterol Motil. 2021;33(1):e14058.
- Katz PO, et al. ACG Clinical Guideline for the Diagnosis and Management of GERD. Am J Gastroenterol. 2022;117(1):27–56.
- Yadlapati R, et al. AGA Clinical Practice Update on the Personalized Approach to the Evaluation and Management of GERD. Clin Gastroenterol Hepatol. 2022;20(5):984–994.
This page is general education. It can’t account for your history, test results, or other conditions, so please discuss your situation with your own clinician.