Understanding the Nerve Excitability Test for the Facial Nerve – A Physio360 Guide.

INTRODUCTION;

When it comes to facial weakness, twitching, or unexplained asymmetry in expressions, the facial nerve (cranial nerve VII) is often at the centre of investigation. At Physio360, we specialise in accurate neurological assessments, and one essential tool in our diagnostic arsenal is the Nerve Excitability Test (NET) for the facial nerve.

This non-invasive test plays a vital role in identifying facial nerve lesions, gauging nerve damage, and tracking recovery progress in conditions like Bell’s palsy, facial neuropathy, or facial paralysis.

What is the Facial Nerve?

The facial nerve is the seventh cranial nerve responsible for:

• Facial expressions (smiling, frowning, blinking)

• Lacrimal (tear) and salivary gland control

• Taste sensation in the front two-thirds of the tongue

Damage to this nerve can result in facial drooping, loss of expression, drooling, and incomplete eye closure, which can significantly affect one’s confidence and quality of life.

What is a Nerve Excitability Test?

A Nerve Excitability Test (NET) is a diagnostic electrophysiological test used to evaluate the responsiveness and integrity of a peripheral nerve, in this case, the facial nerve.

It helps in detecting:

• Partial or complete nerve degeneration

• Location of the lesion

• Extent of damage

• Prognosis and treatment planning

At Physio360, we use this test to track nerve recovery, especially in patients recovering from Bell’s palsy, Ramsay Hunt Syndrome, facial trauma, or post-surgical facial nerve palsy.

When is NET for the Facial Nerve Recommended?

You may be advised to undergo this test if you experience:

• Sudden facial weakness or drooping

• Loss of facial expressions

• Inability to close one eye

• Unexplained facial twitching

• Facial numbness following infection or surgery

• Recovery monitoring after facial nerve damage

If you’ve been diagnosed with Bell’s palsy, this test can help determine the degree of nerve damage and guide the recovery plan.

How is the Nerve Excitability Test Performed?

At Physio360, our procedure is simple, safe, and carried out by trained professionals. Here's what typically happens:

1. Preparation

• The skin is cleaned to ensure optimal contact.

• Surface electrodes are placed over specific facial muscles (usually orbicularis oculi or orbicularis oris).

  
  

2. Stimulation

• A controlled electrical stimulus is applied over the facial nerve at the stylomastoid foramen area.

  
  

3. Response Observation

• We observe and compare the muscle response on the affected side versus the unaffected side.

• The minimal stimulus required to produce a muscle contraction (called “threshold”) is recorded.

  
  

4. Comparison

• A higher threshold or absent response may indicate nerve damage.

• Serial tests help in tracking improvement over time.

  
  

What Do the Results Mean?

• Normal response: Indicates healthy nerve conductivity.

• Delayed or decreased excitability: Suggests partial nerve degeneration.

• No response: Often points toward complete nerve degeneration or severe injury.

Understanding these results helps tailor physiotherapy and medical management effectively.

Role of Physiotherapy After NET at Physio360

The Nerve Excitability Test is not just diagnostic—it’s the foundation of our rehab approach. At Physio360, once the NET results are in, we begin a customised facial rehabilitation program that may include:

✴️ Facial Neuromuscular Retraining (FNMR)

• Re-educates the brain-muscle connection

• Improves coordination and reduces involuntary movements

✴️ Electrical Stimulation

• Non-invasive stimulation of facial muscles

• Promotes nerve-muscle interaction and aids reinnervation

✴️ Mirror Therapy

• Boosts visual feedback and aids symmetry restoration

✴️ Facial Massage and Tactile Stimulation

• Prevents muscle stiffness and enhances circulation

✴️ Exercises for Symmetry and Strength

• Targeted movements to restore voluntary muscle function

  
  

Common Conditions We Treat with NET at Physio360.

• Bell’s Palsy

• Facial Nerve Injury post-surgery

• Ramsay Hunt Syndrome

• Tumour-induced nerve damage

• Stroke-related facial paresis

We track patient progress using repeat NETS to ensure that recovery is on the right path and adjust physiotherapy protocols accordingly.

Why Choose Physio360 for Facial Nerve Rehabilitation?

• Experienced Neuromuscular Physiotherapists

• Advanced Nerve Testing Equipment

• Personalised Recovery Programs

• Affordable and Transparent Pricing

• Collaborative Care with Neurologists and ENT Specialists

• Trackable Progress with Follow-up Testing

We take pride in helping patients regain their smile, both physically and emotionally.

Final Thoughts.

The Nerve Excitability Test for the Facial Nerve is a crucial step in diagnosing and managing facial nerve dysfunction. At Physio360, we combine accurate testing with compassionate care to ensure you receive the best possible treatment for facial nerve recovery.

If you or someone you know is struggling with facial weakness or recovering from Bell’s palsy, early testing and intervention can make all the difference.

REFERENCE AND RESEARCH ARTICLE ;

1.Nerve excitability test in facial palsy: limitations in its use, based on a study of 130 caseshttps://pubmed.ncbi.nlm.nih.gov/5081746/.

2.Facial nerve electrodiagnostics for patients with facial palsy: a clinical practice guidelinehttps://pmc.ncbi.nlm.nih.gov/articles/PMC7286870/