Beyond Bell's Palsy: Skull Base Pathology Presenting with Facial Paralysis

Bell's palsy is the most common diagnosis in patients presenting with acute facial paralysis. It is important to understand how occult skull base pathology may mimic idiopathic facial paralysis. This study evaluates the incidence and clinical predictors of occult skull base pathology among patients initially diagnosed with Bell's palsy.

A retrospective review was performed of patients who presented between January 2002 and January 2024 with an initial diagnosis of Bell's palsy and had at least 12 months of follow-up. Patients with known malignancy, trauma, infectious etiologies of facial paralysis, or clinically obvious cancer-associated paralysis were excluded. Demographic data, initial medical therapy, imaging findings, neurological examination findings, and final diagnoses were analyzed.

Among 345 patients with presumed Bell's palsy, occult skull base pathology was identified in 21 (6.1%). Additional cranial neuropathies were present in 19 patients (90.5%), most commonly ipsilateral facial numbness (n=16), vocal fold paralysis (n=4), and hypoglossal nerve palsy (n=3). Only 2 patients presented with isolated facial paralysis. The most common diagnosis was squamous cell carcinoma (n=12). No patient with concomitant facial numbness, vocal fold paralysis, or hypoglossal nerve dysfunction had benign pathology.

Additional cranial neuropathies-particularly trigeminal nerve sensory deficits, vocal fold paralysis, and hypoglossal nerve dysfunction-are strongly associated with occult skull base malignancy in patients presenting with presumed Bell's palsy. These findings support prompt skull base imaging and comprehensive evaluation in patients with facial paralysis accompanied by additional neurological deficits to exclude nonidiopathic causes.