Gastroenterology Coding Alert

Question: My gastroenterologist's note states, "I inserted an impedance probe affixed to flexible nasal catheter tubing through the nose down to the lower esophageal sphincter. I followed the location of the lower sphincter by manometry. The impedance probe contains several electrodes that make up multiple measure segments each 2.0 cm in length. The measuring segments are located at intervals above the proximal border of the lower esophageal sphincter. The patient swallows a liquid bolus. As the bolus passes through the esophagus, I measured the average electrical resistance between two adjacent electrodes (impedance)." How should I report this?

Florida Subscriber

Answer: Your gastroenterologist performed an esophageal function test. You should report 91037 (Esophageal function test, gastroesophageal reflux test with nasal catheter intraluminal impedance electrode[s] placement, recording, analysis and interpretation) for a recording of one hour or less.

For more than one hour, you should report 91038 (... prolonged [greater than 1 hour, up to 24 hours).

Tips: If you report 91038, you should use the date your physician acquired the study for analysis.

Also, if your physician does both the performance of esophageal function (91037-91038) and motility studies (91010-91012), you should report both procedures. The same goes if your physician does both the performance of nasal catheter esophageal function (91037-91038) and esophageal pH studies (such as 91034, Esophagus, gastroesophageal reflux test; with nasal catheter pH electrode[s] placement ...).

Don't forget: If your gastroenterologist performs the esophageal function test in an outpatient facility or inpatient setting, you should add modifier 26 (Professional component) to 91037 or 91038 to indicate the physician interpretation.

Check this: You may see terms in your physician's note that alert you to the fact that he is performing an esophageal function test. The electrodes detect esophageal contraction, expansion and movement of the liquid or solid bolus through the esophagus in real time, as well as any gastroesophageal reflux. Your physician evaluates the esophageal function by calculating the bolus transport time (BTT), which is the time the bolus takes to pass from the proximal measuring segment and exit through the distal measuring segment.

Your physician will also evaluate the contraction wave velocity (CWV), which is the speed of the contraction wave from the proximal measuring segment to the distal measuring segment. You may see this test referred to as "multichannel intraluminal impedance testing" or MII.