2 Clinical Trials for Various Conditions
Refractory epilepsy, meaning epilepsy that no longer responds to medication, is a common neurosurgical indication in children. In such cases, surgery is the treatment of choice. Complete resection of affected brain tissue is associated with highest probability of seizure freedom. However, epileptogenic brain tissue is visually identical to normal brain tissue, complicating complete resection. Modern investigative methods are of limited use. An important subjective assessment during surgery is that affected brain tissue feels stiffer, however there is presently no way to determine this without committing to resecting the affected area. It is hypothesized that intra-operative use of a tonometer (Diaton) will identify abnormal brain tissue stiffness in affected brain relative to normal brain. This will help identify stiffer brain regions without having to resect them. The objective is to determine if intra-operative use of a tonometer to measure brain tissue stiffness will offer additional precision in identifying epileptogenic lesions. In participants with refractory epilepsy, various locations on the cerebral cortex will be identified using standard pre-operative investigations like magnetic resonance imagin (MRI) and positron emission tomography (PET). These are areas of presumed normal and abnormal brain where the tonometer will be used during surgery to measure brain tissue stiffness. Brain tissue stiffness measurements will then be compared with results of routine pre-operative and intra-operative tests. Such comparisons will help determine if and to what extent intra-operative brain tissue stiffness measurements correlate with other tests and help identify epileptogenic brain tissue. 24 participants have already undergone intra-operative brain tonometry. Results in these participants are encouraging: abnormally high brain tissue stiffness measurements have consistently been identified and significantly associated with abnormal brain tissue. If the tonometer adequately identifies epileptogenic brain tissue through brain tissue stiffness measurements, it is possible that resection of identified tissue could lead to better post-operative outcomes, lowering seizure recurrences and neurological deficits.
The purpose of this study is to measure if the drug called Everolimus effects mTOR signaling (an electrical activity signal in the brain) in patients with Tuberous Sclerosis Complex (TSC) and Focal Cortical Dysplasia (FCD) with treatment resistant epilepsy (TRE) who will be undergoing brain surgery. One group of patients will be treated with Everolimus, and another will not. Researchers will determine if there is a difference in mTOR signaling between the patients who were treated with Everolimus and those who were not. Previous studies have suggested that Everolimus may reduce seizure activity in TSC patients by decreasing mTOR signaling. Since patients with FCD may also have excess mTOR signaling brain activity, Everolimus may also reduce seizure activity in these patients. The drug Everolimus is approved by the Food and Drug Administration to treat specific types of breast, pancreatic, and kidney cancer, a kidney tumor called an angiomyolipoma (common in patients with TSC), and TSC patients who have a brain tumor called a subependymal giant cell astrocytoma (SEGA). However, in this research it is considered to be an investigational since it is not approved for reduction in mTOR signaling and a decrease in seizure frequency. Researchers believe that Everolimus may be useful in reducing something called cortical hyperexcitability, which is the excess brain activity that can contribute to seizures.