Gastroenterology Coding Alert

Question: When billing an esophageal motility and pH study, should I bill both on the same day or should I bill the pH on the second day? Also, is there a procedure code for reading them?

California Subscriber
Answer: The billing dates for the esophageal motility and pH studies may vary based on when the studies are completed, says Carol Pohlig, BSN, RN, CPC, Hospital of the University of Pennsylvania in Philadelphia. When 24-hour pH monitoring (code 91033) is performed, the date of service (and the billing date) is the day the monitoring is completed, which is usually the day after the probe was inserted and monitoring was initiated. When monitoring is conducted for a shorter time, such as 12 or 14 hours, it is generally completed on the same calendar day that it was initiated. Code 91032 should be used to report pH monitoring that is less than 24 hours long.
 
If the motility test was performed on the same day the pH test was completed, report the same date of service for both procedures. If the motility test was performed on a different date from the pH monitoring, you should report different dates of service.
 
To indicate that the gastroenterologist only read or interpreted the results, you should add modifier -26 (professional component) to the procedure code.