Specific surgical treatment for epilepsy has been rapidly
developed over the last decade, and is now a well-established form of treatment
for certain kinds of seizure.
In order for these operations to be successful, doctors
need two essential pieces of information:
1. From where exactly in the brain
do the seizures originate? Answering this question requires identification of
the "seizure focus". Removal of this region will prevent the seizure from
starting or spreading.
2. What are the normal functions of that part of the
brain and the brain tissue close by? The neurosurgeon needs to remove epileptic
brain, but at the same time must be very careful not to damage normal brain
Which patients qualify for
People with epilepsy who may benefit from surgery are most
often those with complex partial seizures, originating in one of the temporal
lobes, which are not controlled successfully with medications. Patients are
screened extremely carefully to be sure that they are suitable candidates for
surgery, and will certainly have already had routine EEGs and brain scans.
Before surgery, they may need to undergo more specialised EEG monitoring to
precisely identify the seizure focus, detailed MRI brain scans, and SPECT or PET
scans which can confirm the site of seizure activity.
Surgery is usually avoided in regions of the brain with
essential functions, such as control of movement or use of language. There are
techniques to help identify exactly where these regions are in order to better
avoid them during surgery.
The commonest operation is removal of
the tip of the temporal lobe on one side - a so-called anterior temporal
lobectomy. As with most other neurosurgery, this is a major procedure, done
under full general anaesthetic and requiring a hospital stay of several days.
Most surgeries are uncomplicated, and some 60-70% of patients can expect their
seizures to be cured for good. Modern epilepsy surgery offers hope to many
patients with previously intractable seizures.