From the Guidelines
Bell's palsy typically presents with unilateral facial paralysis, facial droop, pain around the jaw or ear, hyperacusis, tinnitus, reduced taste, and decreased lacrimation or salivation.
Common Presentations
- Facial droop
- Pain around the jaw or ear
- Hyperacusis
- Tinnitus
- Reduced taste
- Decreased lacrimation or salivation
Causes and Diagnosis
The facial nerve (CN VII) is a complex nerve that contains branchial motor, visceral motor, general sensory, and special sensory functions, and its paralysis can result from various causes, including inflammation, tumors, vascular lesions, and trauma 1. Bell's palsy, the most common cause of acute peripheral facial nerve palsy, is attributed to inflammation of the facial nerve, which may be idiopathic or due to herpes simplex virus 1.
Imaging and Treatment
In general, Bell's palsy patients do not need to be imaged unless the symptoms are atypical, recurrent, or persistent for 2 to 4 months 1. When imaging is considered, MRI is the method of choice, and high-resolution thin-cut contrast-enhanced MRI is especially useful for evaluating the facial nerve and excluding other causes of facial nerve palsy 1. Treatment with steroids can hasten recovery, and most patients experience complete recovery of function by 6 months 1.
From the Research
Presentations of Bell's Palsy
The presentations of Bell's palsy include:
- Unilateral facial weakness or paralysis, which can occur suddenly and progress over 48 hours 2
- Facial muscle paresis or complete paralysis on one side of the face 2, 3
- Inability to voluntarily move facial muscles on the affected side of the face 3
- Partial or complete inability to close the eyelid, leading to potential eye injury 3
- Unilateral facial paralysis over one to three days with forehead involvement and no other neurologic abnormalities 4
- Symptoms typically peak in the first week and then gradually resolve over three weeks to three months 4
- Incomplete eyelid closure with resultant dry eye as a common short-term complication 4
- Permanent facial weakness with muscle contractures as a less common long-term complication 4
Characteristics of Bell's Palsy
Some key characteristics of Bell's palsy are:
- It is a common cranial neuropathy leading to facial muscle paresis or complete paralysis 2
- It is considered chiefly idiopathic and is diagnosed by the exclusion of other causes 2
- It can cause physical and psychological complications and negatively impact patients and their relatives 2
- The risk is high in diabetics, hypertensives, women who are pregnant, obese, and people with upper respiratory tract infections 2
- Approximately 70 to 80 percent of patients will recover spontaneously 4