Differential Diagnosis for Unilateral Facial Weakness
- Single most likely diagnosis
- Bell's Palsy: This is the most common cause of unilateral facial weakness, accounting for approximately 70% of cases. It is characterized by sudden onset of facial weakness or paralysis, often accompanied by pain behind the ear. The exact cause is unknown, but it is thought to be related to viral infection or autoimmune response.
- Other Likely diagnoses
- Stroke or Transient Ischemic Attack (TIA): Unilateral facial weakness can be a symptom of a stroke or TIA, especially if accompanied by other symptoms such as arm or leg weakness, speech difficulties, or visual disturbances.
- Lyme Disease: Lyme disease, caused by the bacterium Borrelia burgdorferi, can cause unilateral facial weakness, particularly in endemic areas.
- Ramsay Hunt Syndrome: This is a viral infection caused by the varicella-zoster virus, which can cause unilateral facial weakness, ear pain, and vesicles in the ear.
- Do Not Miss diagnoses
- Brain Tumor: A brain tumor, such as an acoustic neuroma or meningioma, can cause unilateral facial weakness, especially if accompanied by other symptoms such as hearing loss, tinnitus, or balance problems.
- Multiple Sclerosis: Multiple sclerosis can cause unilateral facial weakness, particularly in younger patients, and is often accompanied by other symptoms such as vision loss, numbness, or weakness in the limbs.
- Cerebellopontine Angle Tumor: A tumor in the cerebellopontine angle, such as a schwannoma or meningioma, can cause unilateral facial weakness, hearing loss, and balance problems.
- Rare diagnoses
- Moebius Syndrome: A rare congenital disorder characterized by unilateral or bilateral facial weakness, often accompanied by other symptoms such as limb abnormalities or cognitive impairment.
- Melkersson-Rosenthal Syndrome: A rare genetic disorder characterized by recurrent episodes of unilateral facial weakness, swelling of the face and lips, and the development of folds and furrows in the tongue.
- Facial Hemiatrophy: A rare condition characterized by unilateral facial weakness, atrophy of the facial muscles, and other symptoms such as seizures or cognitive impairment.