ICD 10 Coding Alert

The ICD-10 descriptor mirrors the old ICD-9 choice.

When your neurologist diagnoses Bell’s palsy, it means the patient experiences temporary facial paralysis when the nerves that control the facial muscles on one side of the face become swollen or inflamed. As a result of this condition, half of the patient’s face droops and she has difficulty closing her eye on that side.

Code changes: When coding by ICD-9, you reported 351.0 (Bell’s palsy) to describe the condition. This code was also applicable for patients who suffered from facial palsy. Now with ICD-10, you submit G51.0 (Bell’s palsy) as the diagnosis. Because the descriptor is identical to 351.0’s descriptor, you will not adopt any significant changes related to the code’s function.

Documentation: Since no specific test confirms Bell’s palsy, your physician’s initial diagnosis will largely depend on observation. The patient’s history may indicate a sudden unexplained episode of unilateral facial weakness or paralysis. Some may report a headache, tearing, changes in the amount of saliva and tears, drooling, difficulty eating and drinking, change in facial appearance, impairment of taste, and hearing loss as part of the onset of Bell’s palsy. The physician would most likely obtain a complete history of current and prior injuries and illnesses.

In the physical exam, the physician may note facial asymmetry, the patient’s inability to move muscles on the affected side of the face, drooling, increased distance between the top and bottom eyelids, a smooth forehead, and a flattened crease between the nose and the upper lip. Standard guidelines define that the patient should be examined for the extent of facial dysfunction, and may be graded using the House-Brackman Scale from grades I through VI, with grades I and II as having good outcomes, grades III and IV as producing moderate facial dysfunction, and grades V and VI as having poor outcomes.

Coder tips: Physicians might perform electroneurography (ENoG) of the facial nerve primarily to diagnose Bell’s palsy and/or other facial paralysis disorders. You would report 92516 (Facial nerve function studies [e.g., electroneuronography]) when your physician performs this procedure.  

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