Radiology Coding Alert

Question: Many of our dialysis patients have several angioplasties or thrombectomies performed because of stenosis and clotting of their AV grafts. When we report a second angioplasty or thrombectomy conducted during the global period of the previous procedure, should we use modifier -58 or -78?

Arkansas Subscriber

Answer: Neither would be correct. Because modifier -58 (Staged or related procedure or service by the same physician during the postoperative period) is used for an additional service that was planned prospectively, it would not likely apply to this scenario. Stenosis and clotting of an arteriovenous (AV) graft are not uncommon, but corrective angioplasty or thrombectomy (e.g., 36870, Thrombectomy, percutaneous, arteriovenous fistula, autogenous or nonautogenous graft [includes mechanical thrombus extraction and intra-graft thrombolysis]) usually does not require a planned service. If this type of service is planned, it is usually provided on the same date of service as the original intervention. In the unlikely event that a planned, but delayed secondary intervention is provided, modifier -58 would be correct.

Modifier -78 is defined as a return to the operating room for a related procedure that is directly related to the performance of the initial procedure during the postoperative period. A second obstruction is not necessarily associated with the original procedure. Grafts often produce clots with no correlation to the surgery.

Instead of modifier -58 or -78, coders should append modifier -79 (Unrelated procedure or service by the same physician during the postoperative period) to the second procedure.

You must be careful not to append modifiers for services that are included in the surgical package. For instance, treatment for a minor infection at the site would not be payable because it would be considered normal follow-up.