Split-brain surgery, also known as corpus callosotomy, is a medical procedure that involves the severing of the corpus callosum, which connects the two hemispheres of the brain, to treat epilepsy. Unlike other epilepsy-treating procedures, a callosotomy does not involve the removal of any brain tissue.
Significance
Epilepsy patients undergo surgery when anti-seizure medication has proven ineffective. There are many types of surgeries to treat epilepsy, but split-brain surgery is the preferred option when there are multiple sources for a seizure (or no source at all) as opposed to one easily removable focal point.
Procedure
The neurosurgeon makes an incision at the top of the patient's skull to allow access to the brain. Once the corpus callosum is revealed by pulling the brain's two hemispheres apart, the surgeon cuts and removes the fibers connecting the halves of the brain.
Initially, the procedure is a "partial callosotomy," which removes only two-thirds of the corpus callosum. The rest of the fibers are cut in a "complete callosotomy" only if the initial removal does not decrease the number of seizures.
Effects
Severing the corpus callosum fibers that connect the brain's hemispheres keeps the seizure from spreading to both sides of the brain, thus preventing a grand mal seizure and greatly reducing the instances of seizure, especially with continued use of medication.
Dangers
In addition to the general hazards of surgery, patients after the procedure may have trouble in use of the non-dominant hand, deciding the right word to say, or even connecting words with images. This is the result of a lack of communication between the brain's hemispheres.
Alternative Treatments
Some patients choose to undergo vagus nerve stimulation to treat their epilepsy via electrical impulses being sent to the brain. In terms of medication, the creation of new anti-seizure drugs has reduced the need for split-brain surgery.
Tags: corpus callosum, brain hemispheres, split-brain surgery, treat epilepsy