Hemifacial Spasm (HFS) is a neurological condition characterized by involuntary, repetitive contractions of the muscles on one side of the face. It occurs when a blood vessel compresses the facial nerve (cranial nerve VII) at its origin in the brainstem, causing abnormal electrical signals that trigger muscle twitching. Symptoms typically start around one eye and may gradually involve the cheek and mouth. Microvascular Decompression (MVD) surgery is the most effective and long-lasting treatment — addressing the root cause by relieving pressure on the facial nerve.
Symptoms
- Intermittent eye twitching (often first symptom)
- Progressive involuntary closure of the eye (blepharospasm)
- Facial twitching spreading to cheek, mouth, and neck
- Asymmetric facial movements, especially during speech or stress
- Mild facial pain or pressure (less common)
- Severe cases: constant facial tightness or difficulty keeping the eye open
Symptoms typically worsen with fatigue, anxiety, or concentration and disappear during sleep.
Causes
The most common cause is vascular compression of the facial nerve root exit zone, usually by:
- Anterior inferior cerebellar artery (AICA)
- Posterior inferior cerebellar artery (PICA)
- Vertebral artery
Pulsatile compression irritates the nerve and leads to abnormal transmission of impulses.
Less common causes include tumors, vascular malformations, or post-paralysis nerve hyperactivity.
Diagnosis
- Neurological Examination: Confirms unilateral facial muscle contractions with preserved consciousness and sensation.
- MRI with High-Resolution Sequences (CISS/FIESTA): Visualizes artery or vein compressing the facial nerve at its brainstem origin.
- Occasionally, MRI angiography (MRA) or CT angiography is used for surgical planning.
Treatment Options
1. Medical & Non-Surgical Management
- Botulinum toxin (Botox) injections: Temporarily weaken overactive muscles, providing relief for 3–6 months. Repeated injections required; do not correct vascular compression.
- Medications: Carbamazepine or clonazepam may reduce twitching but are usually less effective long-term.
2. Microvascular Decompression (MVD)
The definitive treatment offering highest success and lowest recurrence rates.
- Performed under general anesthesia via small incision behind the ear.
- Tiny craniotomy allows surgeon to identify and separate compressing vessel from facial nerve under microscope.
- Teflon pad placed between vessel and nerve; nerve preserved intact.
- Immediate or gradual resolution of spasms in >90% of patients; low recurrence <10%.
Recovery & Follow-Up
- Hospital stay: 2–3 days
- Mild dizziness or headache may occur temporarily
- Resume normal activities in 2–4 weeks
- Facial twitching improves immediately or within weeks
- Follow-up MRI may confirm decompression success
- Patients previously reliant on Botox usually no longer need injections after MVD
Risks & Complications
Microvascular decompression is safe when performed by experienced neurosurgeons. Rare complications include:
- Temporary facial weakness or numbness
- Hearing loss (due to proximity to auditory nerve)
- Cerebrospinal fluid (CSF) leakage (usually managed conservatively)
- Infection or bleeding (very rare)
Permanent complications are uncommon, and most patients achieve excellent functional and cosmetic recovery.
Prognosis
- >90% long-term success with microvascular decompression
- Recurrence <10% (can be re-treated successfully)
- Botox therapy remains an alternative for patients not suitable for surgery
- Quality of life typically improves dramatically after successful MVD
Patient Advisory
Hemifacial spasm is benign but progressive — early evaluation by a neurosurgeon prevents years of discomfort and functional limitation. Microvascular decompression offers a permanent cure for most patients by addressing the true cause rather than symptoms. Each patient’s anatomy is unique; surgical candidacy must be evaluated through high-resolution MRI and expert consultation. Do not base medical decisions solely on online information.