Abstracts

mTOR Inhibitors Alter Cortical Excitability in Tuberous Sclerosis: An Electrical Stimulation Mapping Study

Abstract number : 2.065
Submission category : 3. Neurophysiology / 3E. Brain Stimulation
Year : 2023
Submission ID : 723
Source : www.aesnet.org
Presentation date : 12/3/2023 12:00:00 AM
Published date :

Authors :
Presenting Author: Kishore Vedala, MD – Cincinnati Children's Hospital

Ravindra Arya, MD – Cincinnati Children's Hospital; Gewalin Aungaroon, MD – Cincinnati Children's Hospital

Rationale: Tuberous Sclerosis Complex (TSC) is characterized by a high incidence of drug-resistant epilepsy (DRE) and alterations in neuronal properties. We used electrical stimulation mapping (ESM) of functional responses and associated after-discharges (ADs) and unwanted electrical stimulation-induced seizures (EIS) to explore longitudinal differences in cortical excitability in TSC patients compared to MRI-negative DRE as well as the impact of mTOR inhibitors in TSC. 

Methods: Invasive ESM recordings were reviewed in twenty patients with TSC and ten patients with MRI-negative etiology of DRE. Data was collected on the age of patients, type of electrodes (SEEG vs SDE), duration of epilepsy, whether mTOR inhibitor was used, and the incidence and thresholds of functional responses (stratified by type of functional response), ADs, and EIS. Data were analyzed using linear and generalized linear mixed models.

Results: Patients with TSC required a lower threshold to induce motor responses (slope -1.148; p= 0.037) and ADs (slope -0.711; p< 0.001) compared to patients with MRI-negative DRE. Patients with TSC also had a higher incidence of motor responses (OR 4.458; p< 0.001) and ADs (OR 1.746; p= 0.006) when compared to patients with MRI-negative DRE. In patients with TSC, mTOR inhibitors increased the threshold for motor response (slope 0.235; p= 0.008) and decreased the incidence of face motor and language response (OR 0.091; p< 0.001, and OR 0.156; p= 0.022, respectively). Moreover, mTOR inhibitors increased the threshold for AD induction (slope 0.105; p= 0.006) and decreased the incidence of ADs (OR 0.397; p< 0.001).
Neurophysiology