Radiology Coding Alert

Question: Our MRI technicians indicate that there could be two separate studies performed on the same extremity. For instance, an MRI of the thigh and an MRI of the calf. How do 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.

Idaho Subscriber  
Answer: This is not rare, but some practices report success assigning 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). This modifier alerts local Medicare carriers and other insurers that medical necessity required the procedure to be done twice on one date. The radiologist should clearly document the conditions and reasons for the multiple procedures in the medical record. Furthermore, the radiologist should report the services as two separate and distinct studies (e.g., 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.
 
Other coding professionals advise that practices be careful in instances like these, noting that this approach may not withstand an audit. These experts recommend reporting the study only once, and billing twice may be justified only if two separate orders come in at two different times of the day. Coders should ask insurers for their policies in this situation.