Radiology Coding Alert

Question: Our MRI technician performed an MRI of the thigh and an MRI of the calf during the same session. How should I code for these separately, since 73718 refers to "lower extremity"? Our carriers deny the claim when we report 73718 twice (for the two areas), because they see the leg as a single body part, whereas our techs divide the leg into two parts.

New York Subscriber

Answer: Payers differ in their reporting guidelines for this service. Empire Medicare, a Part B carrier in New York and New Jersey, for example, has a local medical review policy (LMRP) that discusses MRIs of multiple organs, although the policy does not specifically address extremities. The LMRP states, "When multiple organs (for example, liver and gallbladder) located in the same body area are reported on the same day, payment should be limited to one study of that body area. If more than one body area is reported (such as brain and abdomen), payment should be made for each area studied."
 
Many insurers only reimburse the same code twice if you receive two separate orders at different times during the same day.
 
Some insurers may allow you to assign one code twice (e.g., 73718, Magnetic resonance [e.g., proton] imaging, lower extremity other than joint; without contrast material[s]), with modifier -51 (Multiple procedures) appended. This modifier alerts local Medicare carriers and other insurers that medical necessity required the procedure to be done twice on one date. This would be rare, however, because the ordering physician would most likely request only one lower-extremity MRI.
 
The radiologist should clearly document the conditions and reasons for the multiple procedures in the medical record. The radiologist should report the services as two separate and distinct studies (for example, MRI thigh and MRI calf) rather than "an MRI of the lower extremity to include the thigh and calf."
 
The payer may require the documentation before paying the claim. Your best bet is to contact your carrier ahead of time to determine its policy for MRIs performed on separate parts of the same leg. Most likely, the insurer will only allow you to code the examination once, because the code describes an examination of the entire extremity or any part thereof.

 - The answers for You Be the Coder and Reader Questions were reviewed by Cindy C. Parman, CPC, CPC-H, RCC, co-owner of Coding Strategies Inc. in Dallas, Ga; and Gary S. Dorfman, MD, FACR, FSIR, representative to the AMA's CPT Advisory Committee.