Neurology & Pain Management Coding Alert

Question: Our physician did a left greater occipital nerve (GON) block. How can we report this procedure? Can we submit code 64402?

Michigan Subscriber

Answer: For a greater occipital nerve (GON) block on the left side, you should submit code 64405 (Injection, anesthetic agent; greater occipital nerve) and append modifier LT (Left side).

Do not report 66402: You should not report code 64402 (Injection, anesthetic agent; facial nerve) for GON block. Code 64402 is for facial nerve block. The facial nerve, also known as the seventh cranial nerve, provides motor control of all of the muscles of facial expression.

Check the location of the block: If you are confused between GON and facial nerve blocks, you can check the site of injection in the procedure note. Your physician should clearly indicate the injection location in his documentation. In fact, some providers include in their documentation a small illustration that can be marked with the various injection sites. This will help you to ensure that you're choosing the correct nerve block code each time.

Your physician will typically administer the facial nerve block just in front of the ear. On the contrary, your physician will administer the GON block just above the base of the skull. The GON originates from the C2 spinal nerve and provides sensory innervation to the back of the scalp extending to the top of the head.

Diagnosis code: You should also confirm why your physician did the GON block. This will help you submit the most appropriate diagnosis code. For example, if you read that your physician did the GON block in a patient with occipital neuralgia, you submit ICD-10 code M54.81 (Occipital neuralgia).

Remember to check with your payer: Some payers do not allow coverage for GON injections. For example, United Healthcare's policy on Occipital Neuralgia and Cervicogenic, Cluster and Migraine Headaches states, "Injection of local anesthetics and/or steroids, used as occipital nerve blocks, is unproven and not medically necessary for diagnosing and treating occipital neuralgia or headaches including migraine and cervicogenic headaches."