Radiology Coding Alert

Question: When should I report modifiers GG and GH?


Arkansas Subscriber


Answer: Append modifier GG (Performance and payment of a screening mammogram and diagnostic mammogram on the same patient, same day) when a radiologist reviews the results of a screening mammogram, detects a suspicious abnormality that requires further imaging, and performs a complete diagnostic mammogram as a separate service on the same date.

How to code: Report the screening mammogram with 76092 (Screening mammography, bilateral [two view film study of each breast]). Then append GG to the appropriate diagnostic mammogram code: 76090 (Mammography; unilateral) or 76091 (... bilateral). Payers should reimburse you for both the screening and diagnostic mammograms.

You're unlikely to find a payer that still accepts modifier GH (Diagnostic mammogram converted from screening mammogram on same day). GH describes converting a screening mammogram into a diagnostic mammogram when the radiologist takes additional films to augment the screening rather than performing two complete exams on the same day.

Prior to 2002, Medicare would pay only for the diagnostic exam, whether the physician performed an augmented screening or two complete exams. Now, however, you can receive payment for two complete exams performed on the same date by using modifier GG.

If your payer accepts GH, append it to the diagnostic code, when appropriate. The payer will cover the service as a diagnostic mammogram.