CPT code 91035 represents diagnostic gastroesophageal reflux testing performed with telemetry pH electrode placement. This procedure involves placement of a pH sensor, continuous telemetry recording of esophageal acid exposure, and professional interpretation and reporting. Nationally, accurate coding and documentation for ambulatory pH monitoring are important for appropriate clinical management of gastroesophageal reflux disease (GERD), quality measurement, and claims adjudication.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of clinical indications and procedural components tied to 91035, common payer considerations, and guidance on where to look for coverage policy or medical necessity criteria. The publication outlines benchmarks and utilization context where available, notes typical sites of service (outpatient clinics, ambulatory surgery centers, and hospital outpatient departments), and summarizes what to expect in terms of documentation elements needed to support billing.

This summary is intended for a national audience of clinicians, coding professionals, and policy analysts seeking a concise reference on the clinical purpose and billing context of CPT code 91035.