ACR Radiology Coding Source™ March-April 2010 Q and A

Q: The physician diagnosed and treated two different obstructions through two separate arteriovenous accesses, one at the arterial anastomosis and one in the subclavian vein. Is this reported with two percutaneous transluminal angioplasties (PTAs), one arterial and one venous, or only a venous PTA?

A: All balloon angioplasty of the arteriovenous (AV) dialysis access is coded with one set of angioplasty codes, no matter how many focal stenoses are treated within the AV dialysis circuit. The majority of the time, this is a venous angioplasty code, and would be reported using 35476 and 75978. However, as in this case, if the stenosis in the AV fistula or graft that is treated is at the arterial anastomosis, it may be coded with arterial angioplasty codes 35475 and 75962. This code would then apply to all other stenoses treated within the AV dialysis “vessel.” In other words, all angioplasty within the AV dialysis circuit (considered from the peri-anastomotic vessels near the arterial anastomosis through the axillary vein), would be coded with either 35475 and 75962 or 35476 and 75978. The appropriate code is chosen dependent upon whether a true arterial anastomotic stenosis is treated. Removal of the arterial “plug” occlusion is never coded with a PTA as it is considered to be part of the thrombectomy (coded 36870), not as treatment of an arterial stenosis with angioplasty.

In addition, in this case the angioplasty of a separate subclavian vein stenosis, is reported using CPT codes 35476 and 75978. All lesions treated in the central veins beyond the axillary venous segment would be coded as a single venous angioplasty, indeterminate of how many focal lesions are treated. For therapeutic purposes, the fistula or graft “vessel” is defined as from the arterial anastomosis through the venous anastomosis, as well as the outflow vein, but not including the subclavian vein. Therefore, the venous angioplasty of a central vessel (e.g., the subclavian vein) is appropriately reported in addition to the angioplasty of the fistula graft itself. The clinical indication for treatment of these lesions should be clearly documented in the medical record.

Please note that there are National Correct Coding Initiative (NCCI) edits for the reporting of CPT codes 35475 and 35476 for procedures performed on the same day of service. A modifier (-59) must be used to ensure appropriate reimbursement.

Q: How is an MRI of only the brachial plexus reported?

A: As noted in a coding Q&A in the February 2001 ACR Bulletin, the consensus of the Economics Committee on Coding & Nomenclature is that the choice of the appropriate CPT code for a magnetic resonance imaging (MRI) study of the brachial plexus depends significantly on the clinical indications. For example, an MRI of the chest, focusing on the brachial plexus, is most commonly used in cases of apical lung cancers (Pancoast tumors), while an MRI of the orbit, face and neck may be used to identify head and neck cancers to the level of the thyroid, including the brachial plexus. In the evaluation of a tumor of the shoulder girdle or axilla, including the brachial plexus region, or in the evaluation of a patient with a brachial plexopathy (a non-specific symptom related to the nerve itself that might require imaging), an MRI of the upper extremity would be appropriate.