Surgery for Epilepsy: From Trephination to Innovation

Trephination Set, circa 1771-1830.

Photo by Wellcome Trust

The earliest notion of surgery for epilepsy dates to ancient times. Hippocrates who lived in 400 BC thought trephination, making a hole in the skull, could provide relief from seizures in people who had suffered traumatic head injuries. Fast forward to the early 1500s and well into the 1800s when a growing number of reports of trephination for epilepsy emerged.  

The success of the surgery was uncertain at best, given the frequent complication of infection and the lack of reported long-term seizure freedom. However, as surgeons moved from creating holes in the skull to dipping beneath the skull, case reports began to emerge detailing descriptions of the removal of tumors, scars and abscesses which led to the relief of seizures.  

Advances in Surgery 

The late 19th century brought significant advances aided by the work of Hughlings Jackson. Jackson studied patients with focal seizures to better understand localized function in the human brain. Working alongside Jackson was Sir Victor Horsely, who early in his career was able to show positive outcomes of brain surgery for epilepsy in patients with identified brain lesions. The combined efforts of Jackson and Horsely brought the medical community to accept epilepsy surgery as a feasible treatment which merited further exploration. 

In the early 20th century, Wilder Penfield and Herbert Jasper led the charge to refine surgical techniques for epilepsy. Their methodical approach combined EEG (electroencephalography) recording, brain stimulation and available imaging (cerebral angiography, pneumoencephalography) with neuropsychology testing and aided in localizing both lesions responsible for seizures and also seizure foci that were independent of lesions. In the years that followed, scientists and clinicians were able to realize the critical step of implanting surgical electrodes deep in the brain to identify epileptogenic brain tissue.  

Improving Brain Imaging 

Further advances in surgery emerged with the arrival of modern three-dimensional brain imaging. Computed tomography (CT) scans in the 1970s aided in the visualization of lesions that declared themselves through seizure activity. Magnetic resonance imaging (MRI) with its high-resolution capabilities eventually became the choice pre-operative imaging technique in epilepsy. Functional imaging with positron emission tomography (PET) and fluorodeoxyglucose (FDG) further aided localization of lesions during surgical evaluations with its ability to identify epileptogenic brain tissue.   

The 21st century continues to deliver opportunities for innovative epilepsy surgical care. The refined use of diagnostics (magnetoencephalography, functional MRI, diffusion tensor imaging) and surgical advances (stereotactic radiosurgery, laser interstitial thermal therapy (LITT)) allow for more patients with drug-resistant epilepsy to be identified as surgical candidates and treated with safe, and when possible, minimally invasive image-guided surgical techniques that have the potential to bring seizure freedom and improve quality of life.  

Epilepsy Foundation Supporting Surgery Innovation  

Through the Epilepsy Therapy Project, the Epilepsy Foundation provides seed funds to accelerate therapeutic options for epilepsy. For example, the Epilepsy Foundation supported the early exploratory studies for LITT in epilepsy to improve surgery safety. The company, known as Visualase®, was acquired by Medtronic.  

The Epilepsy Foundation also gave pilot funds to Advanced Scanners to develop better imaging techniques to ensure that surgeons have a more accurate brain map during the surgery to ensure that the removal of tissue is more precise.