Neurophysiology

Sheffield’s Neurophysiology department is one of the largest in the UK.  It provides a region-wide service is provided for Sheffield, Chesterfield, Rotherham, Doncaster, Barnsley, Bassetlaw and occasionally Wakefield, Retford, Lincoln, Scunthorpe and Grimsby.

We carry out a range of neurophysiological tests to measure how the brain and the nerves around it function in order to diagnose and monitor neurological disorders. We see children with many conditions, including epilepsy, sleep disorders and disorders of nerves and muscles. We also monitor parts of the central and peripheral nervous system during surgical procedures.

The Children’s Neurophysiology department performs a wide range of investigations. These include:

• Electroencephalography (EEG)
• Sleep deprived EEG
• Ambulatory EEG
• Video telemetry EEG monitoring
• Nerve conduction studies (NCS) and electromyography (EMG)
• Evoked Potentials (EPs)
• Intra Operative Monitoring (IOM)
• Magnetic Stimulation
• Sleep Studies
• Pre-Surgical Evaluation for Epilepsy

How do I make an appointment?

Patients can be referred for some of our tests by paediatric consultants, however some of our more complex tests will need to be referred by a paediatric neurologist. On receiving a referral we will send you a letter asking you to phone the department and make an appointment at a time that is suitable for you. At this point you will receive a leaflet providing you with all the information you need regarding the test.

More details on the tests we perform

Electroencephalography (EEG)

Electroencephalography (EEG) is a painless recording of the electrical activity of the brain. Small discs called electrodes are placed on the head and a recording of the brain wave activity is taken. You may be asked to perform some deep breathing and look at a flashing light. The test lasts about 45 minutes. The only preparation required is to have clean hair and to have eaten before the test.

Sleep deprived EEG

Sleep deprived EEG requires you to stay up the night before the test. The preparation is the same as the routine EEG. This test lasts about an hour and 20 minutes. Children will be asked to try and fall asleep, although this is not always possible and is not always essential. When necessary melatonin may be prescribed prior to the appointment.

Ambulatory EEG

An ambulatory EEG an EEG that is conducted while you are at home. Children who require an ambulatory EEG will usually have already had a standard EEG recording. The preparation is essentially the same as for a standard EEG, however a small amount of glue is applied to the discs in order to make them more secure. The leads are then tied together and attached to a recording box that you will wear around your waist. You can then leave the hospital and return 24 hours later so that the information can be downloaded. Children usually go home for a further 24 hour recording.

Video telemetry EEG monitoring

Video telemetry EEG monitoring can be performed in the hospital or if suitable in the patient’s home. For inpatient video telemetry, a child can be admitted to the telemetry unit and an EEG is recorded over a period ranging from one to five days. Children will stay alongside a parent in a single room which is specially equipped with video cameras. The child will not be able to leave the ward during the monitoring period. For home video telemetry recordings, children attend the department to have the electrodes applied and families are shown how to set up the recording equipment in their own home. You will have to return to the department with all of the recording equipment every 24 hours so that the information can be downloaded and checked.

Nerve conduction studies (NCS) and electromyography (EMG)

Nerve conduction studies (NCS) and electromyography (EMG) studies are carried out by consultants and are used to study nerve and muscle function. Nerve conduction studies measure how well and how fast the nerves can send electrical signals. NCS are carried out by applying small electrical impulses to the nerves and recording their responses.

An electromyogram (EMG) measures the electrical activity of muscles at rest and during contraction. An EMG study uses a fine needle which is inserted into a muscle in order to assess the health of muscles and the nerve cells that control them. Nerve conduction studies and EMG tests will usually take between 30 minutes to an hour but sometimes take longer.

Evoked Potentials (EPs)

Evoked potentials are a series of tests which can measure how certain nerves are working in response to a stimulus e.g. a flash, a sound or a small electrical impulse. Tests will usually take around one hour but may take longer in some cases.

Intra-operative Monitoring (IOM)

During surgery parts of a patient’s nervous system are monitored in order to reduce the risk of nerve damage and provide guidance to the surgeons. Where possible evoked potential recordings are performed in the department prior to surgery.

Magnetic Stimulation

Magnetic Stimulation is a non-invasive and painless way of stimulating the brain in order to investigate nerve conduction.

Sleep Studies

Sleep studies enable us to gather information about the quality of sleep by recording various signals such as EEG, breathing, movements and more.

Pre-Surgical Evaluation for Epilepsy

Some patients with epilepsy do not respond to epilepsy medication and may be suitable for surgery. We provide a range of tests for pre-surgical evaluation.