If partial seizures originate in areas of the brain that cannot be removed safely, multiple subpial transections are an alternative. The surgeon makes a series of shallow cuts (transections) into the brain's cerebral cortex. These cuts are thought to interrupt some fibers that connect neighboring parts of the brain, but they do not appear to cause long-lasting impairment in the critical functions that these areas perform.
Multiple subpial transections can help to reduce or eliminate seizures arising from vital functional areas of the cerebral cortex. This procedure has been successful in an unusual type of epilepsy called Landau-Kleffner syndrome, at least for a limited time.
Bleeding at the site of the transection is possible, but the procedure is generally well tolerated. Major complications appear to be rare. Transections in language areas of the brain may mildly impair the language function served by that area.