The finding of an acute focal neurological deficit should be treated as an emergency until adequately evaluated and proven otherwise.
Bell’s palsy is the result of a viral infection of the facial nerve. It is not unreasonable for a patient to have bells or another non-stroke related facial weakness on only a portion of the facial nerve, or along multiple nerves.
Arch Intern Med. 2004;164(21):2383.
BACKGROUND: There is controversy regarding whether, and how frequently, other cranial nerve deficits accompany Bell's palsy. We sought to determine prospectively the presence of signs indicating an associated cranial neuropathy in patients with Bell's palsy.
METHODS: All subjects presenting to an emergency department with Bell's palsy over a 2-year period were evaluated. The study included 51 consecutive patients. One patient with Bell's palsy was not examined by a neurologist at the time of presentation and was excluded. The main outcome measure was presence of other cranial nerve deficits.
RESULTS: We identified 4 patients with additional cranial neuropathies (contralateral trigeminal [n=1], glossopharyngeal [n=2], and hypoglossal [n=1]). We also identified 13 patients with ipsilateral facial sensory loss, suggesting an ipsilateral trigeminal neuropathy; 3 patients with a contralateral facial palsy; and 3 patients with hearing impairment.
CONCLUSION: This prospective study indicates that a small percentage (approximately 8%) of patients with otherwise typical Bell's palsy may harbor additional cranial neuropathies.
Ann Emerg Med. 2005 Jul;46(1):64-6.
We report a case of an isolated facial nerve palsy in a young, otherwise healthy man who was found to have a pontine hemorrhage on computed tomography. Pontine hemorrhage is a rare cause of facial nerve palsy and has been reported in the literature as an isolated neurologic finding in only 1 other instance. This case reminds the emergency physician to remain vigilant for alternative causes of facial nerve palsy other than "idiopathic" Bell's palsy.
J Med Case Rep. 2011;5:287. Epub 2011 Jul 5.
INTRODUCTION: Isolated facial nerve palsy usually manifests as Bell's palsy. Lacunar infarct involving the lower pons is a rare cause of solitary infranuclear facial paralysis. The present unusual case is one in which the patient appeared to have Bell's palsy but turned out to have a pontine infarct.
CASE PRESENTATION: A 47-year-old Asian Indian man with a medical history of hypertension presented to our institution with nausea, vomiting, generalized weakness, facial droop, and slurred speech of 14 hours' duration. His physical examination revealed that he was conscious, lethargic, and had mildly slurred speech. His blood pressure was 216/142 mmHg. His neurologic examination showed that he had loss of left-sided forehead creases, inability to close his left eye, left facial muscle weakness, rightward deviation of the angle of the mouth on smiling, and loss of the left nasolabial fold. Afferent corneal reflexes were present bilaterally. MRI of the head was initially read as negative for acute stroke. Bell's palsy appeared less likely because of the acuity of his presentation, encephalopathy-like imaging, and hypertension. The MRI was re-evaluated with a neurologist's assistance, which revealed a tiny 4 mm infarct involving the left dorsal aspect of the pons. The final diagnosis was isolated facial nerve palsy due to lacunar infarct of dorsal pons and hypertensive encephalopathy.
CONCLUSION: The facial nerve has a predominant motor component which supplies all muscles concerned with unilateral facial expression. Anatomic knowledge is crucial for clinical localization. Bell's palsy accounts for around 72% of facial palsies. Other causes such as tumors and pontine infarcts can also present as facial palsy. Isolated dorsal infarct presenting as isolated facial palsy is very rare. Our case emphasizes that isolated facial palsy should not always be attributed to Bell's palsy. It can be a presentation of a rare dorsal pontine infarct as observed in our patient.
Ann Emerg Med. 2014;63(4):428. Epub 2013 Jul 25.
STUDY OBJECTIVE: We evaluate the incidence of potentially incorrect emergency department (ED) diagnoses of Bell's palsy and identify factors associated with identification of a serious alternative diagnosis on follow-up.
METHODS: We performed a retrospective cohort study from California's Office of Statewide Health Planning and Development for 2005 to 2011. Subjects were adult patients discharged from the ED with a diagnosis of Bell's palsy. Information related to demographics, imaging use, and comorbidities was collected. Our outcome was one of the following diagnoses made within 90 days of the index ED visit: stroke, intracranial hemorrhage, subarachnoid hemorrhage, brain tumor, central nervous system infection, Guillain-Barrésyndrome, Lyme disease, otitis media/mastoiditis, or herpes zoster. We report hazard ratios (HRs) and 95% confidence intervals (CIs) for factors associated with misdiagnosis.
RESULTS: A total of 43,979 patients were discharged with a diagnosis of Bell's palsy. Median age was 45 years. On 90-day follow-up, 356 patients (0.8%) received an alternative diagnosis, and 39.9% were made within 7 days. Factors associated with the receiving alternative diagnosis included increasing age (HR 1.11, 95% CI 1.01 to 1.21, every 10 years), black race (HR 1.68; 95% CI 1.13 to 2.48), diabetes (HR 1.46; 95% CI 1.10 to 1.95), and computed tomography or magnetic resonance imaging use (HR 1.43; 95% CI 1.10 to 1.85). Private insurance was negatively associated with an alternative diagnosis (HR 0.65; 95% CI 0.46 to 0.93). Stroke, herpes zoster, Guillain-Barré, and otitis media accounted for 85.4% of all alternative diagnoses.
CONCLUSION: Emergency providers have a very low rate of misdiagnosing Bell's palsy. The association between imaging use and misdiagnosis is likely confounded by patient acuity. Increasing age and diabetes are modest risk factors for misdiagnosis.