I'm not sure how a facility can billl for a global service, or bill for supplies under the performing surgeon's NPI. A lot of times, supplies, medications, and even implants are considered a part of the ASC fee. This all depends on how your contracts are set up. If you are the facility, your fee for many of the radiological components of procedures are again included in the ASC fee. Most of these radiological components (i.e. 77003, 76942) have a payment indicator of N1. This indicator means the fees for these services are not reimbursed seperately; payment included into the procedure. However, other radiological procedures (i.e. 74420, 77778) has revenue codes in which are payable in the ASC. They often have to be billed with another covered service. If you are reporting for the facility, you would use the -TC modifier. If you are reporting for professional services, you would append the -26 modifier. I found reading Medicare's Claims Processing Manual: Chapter 14/ ASC Facilities helpful when billing/ reporting ASC services. I would also review your contracts to see how they want you to report/ bill for services.