Outpatient Facility Coding Alert

Question: Our surgeon recently reviewed a patient with masseter muscle hypertrophy and pain. He opted to inject lidocaine into the masseter muscle bilaterally to help the patient get relief from the pain. How do I report this procedure?

New York Subscriber

Answer: Since your clinician administered an injection of a local anesthetic (lidocaine) into the masseter muscle, you will have to choose a code from the range 64400-64489 (Introduction/injection of anesthetic agent [nerve block], diagnostic or therapeutic procedures on the somatic nerves) based on the nerve that your clinician attempted to block. As the masseter muscle is innervated by the mandibular division of the trigeminal nerve, report 64400 (Injection, anesthetic agent; trigeminal nerve, any division or branch) for the procedure.

According to an article in CPT^® Assistant, “The descriptor of code 64400 represents a single injection into a single nerve in the anatomy and sensory distribution of the peripheral trigeminal nerve. Injection of each specific nerve has effects on different anatomy sensation in different areas. The code 64400 is considered to be unilateral and when performed bilaterally can be reported as such.”

Since your clinician performed the procedure bilaterally, append modifier 50 (Bilateral procedure) to 64400 to let the payer know that the procedure was performed on both the sides.

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