Why Does Twitching Continue After MVD for Hemifacial Spasm?

It is completely understandable to feel anxious if your face is still twitching after microvascular decompression (MVD) surgery. However, continued twitching in the weeks or even months after surgery does not necessarily mean the operation failed. This is a common and well-documented phenomenon known as delayed relief ^[1][2].

When the surgeon moves the offending blood vessel away from your facial nerve, the mechanical pressure may be relieved immediately. But the nerve and the surrounding systems often need time to recover.

What is Delayed Relief?

Delayed relief means that your facial spasms gradually fade away over time rather than stopping the moment you wake up from surgery. Across various studies, it is estimated that roughly 25% to 30% of patients experience this delayed recovery ^[3].

The timeline varies widely from person to person:

• The first few weeks: In one large study, the median time for patients to achieve lasting symptom relief was about 30 days ^[1].
• Up to 6 months: A majority of patients who experience delayed relief will see their spasms stop within the first 6 months ^[4].
• The one-year mark: Recovery can fluctuate, with spasms fading, briefly returning, and fading again. Many neurosurgeons wait up to a full year before making a final judgment on the surgery’s success ^[5].

Note: Having a brief, completely spasm-free period in the first week after surgery was statistically associated with a higher chance of long-term relief in one study ^[6]. However, this is just a statistical trend. Not having a spasm-free day does not mean your surgery failed, and you should not be alarmed if your spasms are continuous early on.

Why Does the Nerve Take So Long to Heal?

The exact reason for delayed relief is still debated among medical experts, but one proposed explanation involves the nerve’s protective coating, called myelin ^[7].

You can think of myelin like the rubber insulation on an electrical wire. Over time, the pulsing blood vessel may have worn away this insulation, leading to:

1. Hyperexcitability: The nerve becomes hyperactive and starts firing off signals too easily ^[8].
2. Cross-talk (Ephaptic Transmission): Without proper insulation, electrical signals from one nerve fiber can jump to another—similar to a short circuit ^[9]. This causes multiple facial muscles to contract at the same time.

MVD surgery aims to fix the root cause by inserting a tiny pad (often made of Teflon) to separate the blood vessel from the nerve. But separating them does not instantly fix the “frayed wire.” It is believed that the nerve’s insulation must heal, and the hyperactive electrical pathways need time to settle down and normalize ^[7]. As this normalization happens, the “cross-talk” decreases, and the twitching gradually stops ^[9].

It is also important to know that in some cases, persistent spasms mean the decompression was incomplete, the pad shifted, or another blood vessel is still touching the nerve ^[10]. This is why follow-up is critical.

What to Do Now

• Keep your scheduled follow-ups: Do not wait a year to see your doctor. Attend all your planned post-operative visits so your surgeon can track your progress.
• Track your symptoms: Notice if your spasms are less intense, happening less frequently, or affecting fewer areas of your face. Bring this diary to your appointments.
• Do not change your medications: Continue taking your prescribed medicines exactly as directed. Do not stop or adjust them without your surgical team’s approval.

🚨 When to Seek Urgent Medical Attention

Do not wait for your next appointment if you develop new or worsening symptoms that are unrelated to the twitching. Contact your surgeon immediately or go to the nearest emergency room if you experience ^[11][12]:

• Sudden hearing loss or changes in your hearing
• New facial weakness or drooping (different from the spasm)
• Severe dizziness, vertigo, or loss of balance
• Trouble swallowing or hoarseness
• Clear, watery drainage from your incision, nose, or ear (signs of a possible cerebrospinal fluid leak)
• Fever, redness, or pus at the incision site, or a severe, worsening headache

When Further Testing is Needed

If your spasms persist for more than a year, or if they return and worsen after being gone for a long time, your neurosurgeon will reassess your condition ^[10]. They will review your surgical report and may order a high-resolution MRI to look for a shifted pad or missed blood vessel ^[13]. Keep in mind that MRIs are not perfect and cannot always show the exact cause due to surgical artifact, so your doctor will rely heavily on your clinical symptoms.