Neurophysiology

EEG is a non-invasive method used to record electrical activity in the brain. It is used to assess:

• seizures and epilepsy 
• blackouts and unexplained loss of consciousness 
• stroke and transient ischaemic attacks 

There are different types of EEGs, including: 

• routine EEGs, which are typically performed in outpatient settings and provide a snapshot of brain activity
• sleep-deprived EEGs, used to detect epileptiform abnormalities
• ambulatory and prolonged EEGs that are used for extended monitoring (often over 24 hours or more) to capture intermittent events
• day case EEGs, which offer flexibility for patients who require more detailed assessments without overnight stays

These tests help your consultant to differentiate between epileptic and non-epileptic events, tailor anti-epileptic therapy, and monitor the progression of your condition.

Electromyography (EMG) and nerve conduction studies (NCS) are used to evaluate muscle disorders and the associated dysfunction of peripheral nerves, including: 

• entrapment neuropathies, such as carpal tunnel syndrome 
• peripheral neuropathies, which can occur within the context of diabetes 
• amyotrophic lateral sclerosis (ALS), also known as motor neuron disease  

NCS measures the speed and strength of electrical signals in the nerves, while EMG assesses the electrical activity of muscles during rest and contraction. Together, they help pinpoint the location and severity of nerve damage (neurogenic), and within the context of muscle weakness and wasting (myogenic) supports the distinction between nerve and muscle disorders, providing guidance for surgical or rehabilitative interventions. 

If you have episodic symptoms such as seizures, blackouts, or sleep-related disturbances, video telemetry – at times combined with respiratory polygraphy – can help uncover the underlying cause. These tests involve continuous EEG monitoring alongside video recording and respiratory parameters, and can often be carried out at home.

This is particularly useful for: 

• differentiating epileptic seizures from psychogenic non-epileptic events 
• assessing nocturnal seizures and parasomnias 
• investigating sleep disorders with neurological overlap 

By capturing events in real time, your consultant can better understand your condition and therefore provide you with a personalised treatment plan.