My neurosurgeon participated in a stereotactic radiosurgery case where 10 separate metastatic brain lesions were radiated. They all were small so the lesions are considered “simple” from a CPT perspective. I billed 61796 for the first lesion and the add-on code, 61797, times 9 units for the remaining lesions. We got paid for 61796 but the 61797 x 9 units line was denied for “exceeds number of units.” What does that mean?
CPT directs physicians to report a stereotactic radiosurgery add-on code (61797 or 61799) no more than 4 times regardless of number of lesions treated. So when you billed 61797 x 9 units, you went over the limit of 4 units allowed by CPT coding (an ultimately payor) rules. You’ll need to submit a corrected claim with only 4 units of 61797. The remaining 4 lesions cannot be billed when treated on the same day as the first 5 lesions.