Question: Colorado Subscriber Answer: The Correct Coding Initiative (CCI) Version 15.1, effective April 1, 2009, made 15823 and 67904 mutually exclusive, meaning Medicare believes that the two procedures would not typically be performed at the same operative session. In other words, an ophthalmologist would either perform blepharoptosis repair or blepharoplasty, not both. The pair has a modifier indicator of 1. So, as described above, if the ophthalmologist performs 15823 and 67904 on different sites, you may override the bundle with modifier 59.CCI 15.1 lists 15823 as the column 2 code. Therefore, you would append modifier 59 to 15823, if appropriate. Documentation must support why the two services were unbundled.