British Society for Clinical Neurophysiology

...to promote and encourage for the public benefit the science and practice of clinical neurophysiology and related sciences

Lecture Details

Intracranial EEG and Epilepsy Surgery; historical development and recent advances.
Dr Robert Elwes

 Dr Robert Dudley Cary Elwes     MD  FRCP

Dr Elwes studied Medicine at Edinburgh  University and qualified in 1979.  He undertook a research degree at the Institute of Psychiatry in 1990  trained in Neurology and Clinical Neurophysiology at Newcastle Upon Tyne and King’s College Hospital, London.   Dr Elwes was appointed a Consultant at the Maudsley Hospital, London in 1990 and since 1995 has been Consultant Neurologist and Clinical Neurophysiologist at King’s College Hospital where his practice is fully related to epilepsy. He is a senior consultant on the telemetry unit and has particular experience in the assessment of complex epilepsy surgery cases, neuropsychiatric evaluation of epilepsy,  drug treatment of intractable epilepsy and clinical trials in epilepsy.  Dr Elwes has published extensively on the medical and surgical treatment of epilepsy and is an Honorary Senior Lecturer in Neurology at the Institute of Psychiatry, Psychology and Neuroscience.
 

Dr RDC Elwes, Department of Clinical Neurophysiology, King’s College Hospital


Advances in structural imaging and of surgical technique have had a major impact on the use of EEG in epilepsy surgery.  The majority of cases with hippocampal sclerosis, or lesions such as cavernomas or indolent glioneuronal tumours,  are now operated if the scalp EEG findings are congruent and the lesion can be removed without risk of deficit. Intracranial EEG to assess medial temporal epilepsy is now less frequently  performed. Those with TLE and bilateral disease,  atypical electroclinical features (often termed temporal plus epilepsy),  and those with normal MRI may  need invasive evaluation.   A larger number of patients with cortical dysplasia are now seen, often with frontal or perisylvian epilepsy. A significant number have normal structural imaging.  The lesion, when visible, may be subtle, often at the bottom of a sulcus and the extent uncertain. This has led to a greater use of stereoEEG with multiple depth electrodes implanted using robotic surgical techniques. Placement is often guided by functional imaging.  Many predicted that high resolution MRI would obviate the need for intracranial EEG.  By a curious paradox the reverse appears to have happened and streoEEG is now much more widely performed.    The increasing use of neural stimulation to treat epilepsy has had a similar effect. The historical development and current use of EEG in epilepsy surgery, particularly invasive evaluation,  will be reviewed.