Radiology Coding Alert

Question: A patient presented to an outpatient radiology clinic for a magnetic resonance imaging (MRI) scan of the right shoulder. The radiologist confirmed osteolysis in the impression. I’m new to radiology coding and am unfamiliar with osteolysis.

How should I report this encounter?

Nevada Subscriber

Answer: You’ll need one CPT^® code and one ICD-10-CM code to report the encounter. Starting with the CPT^® coding, you’ll choose from the following MRI codes depending on the radiologist’s use of contrast:

• 73221 (Magnetic resonance (eg, proton) imaging, any joint of upper extremity; without contrast material(s))
• 73222 (… with contrast material(s))
• 73223 (… without contrast material(s), followed by contrast material(s) and further sequences)

Codes 73221-73223 are reserved for imaging joints of the upper extremities, which means you’ll use these codes for MRI scans of the elbow, wrist, hand joints, and the shoulder. Take care to avoid 73218-73220 (Magnetic resonance (eg, proton) imaging, upper extremity, other than joint …) when choosing codes for joint MRIs, as these codes are reserved for MRIs of the upper extremities, but not the arm’s joints.

Modifier: Codes 73221-73223 are considered unilateral codes, so you’ll need to append an appropriate modifier to indicate laterality. In your case, you’ll append RT (Right side) to the correct MRI code.

Next, turn to your ICD-10-CM code set to search for the appropriate osteolysis code. According to Dorland’s Medical Dictionary, osteolysis is the “dissolution of bone; applied especially to the removal or loss of the calcium of bone.”

In the ICD-10-CM Alphabetic Index, search for Osteolysis > scapula, which provides you with M89.51- (Osteolysis, shoulder). Turn to the Tabular List to verify the code. Code M89.51- requires a 6th character to specify laterality. You’ll assign M89.511 (Osteolysis, right shoulder) for the osteolysis of the right shoulder diagnosis.