No effect of electrical transcranial direct current stimulation adjunct treatment for epilepsia partialis continua in POLG disease

Abstract

We report a 15-year-old female with POLG-related mitochondrial disease who developed severe multifocal epilepsia partialis continua, unresponsive to standard anti seizure drug treatment and general anesthesia. Based on an earlier case report, we treated her focal seizures that affected her right upper limb with 20-min sessions of transcranial direct current stimulation (tDCS) at an intensity of 2 mA on each of five consecutive days. The cathode was placed over the left primary motor cortex, the anode over the contralateral orbitofrontal cortex. Surface electromyography (EMG) were recorded 20 min before, 20 min during, and 20 min after four of five tDCS sessions to measure its effect on the muscle jerks. The electroencephalography (EEG) was recorded before and after tDCS to measure the frequency of spikes. Our results showed no statistically or clinically significant reduction of seizures or epileptiform activity using EEG and EMG, with this treatment protocol. To our knowledge, this is only the second time that adjunct tDCS treatment of epileptic seizures has been tried in POLG-related mitochondrial disease. Taken together with the positive findings from the earlier case report, the present study highlights that more data are needed to determine if, and under which parameters, the treatment is effective.

POLG1-Related Epilepsy: Review of Diagnostic and Therapeutic Findings

“…The initial search from combined databases returned 228 articles (PubMed = 118 and Embase = 110). A total of 48, including 195 cases, met the inclusion criteria and were used for further evaluation [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 ].…”

Transcranial current stimulation in epilepsy: A systematic review of the fundamental and clinical aspects

“…In contrast to these findings, 3 clinical trials (Varga et al, 2011 ; Assenza et al, 2017 ; Lin et al, 2018 ) and two clinical cases (San-Juan et al, 2018 ; Marquardt et al, 2019 ) reported no effect of cathodal tDCS on IEDs and one clinical study revealed an increase of 48% in interictal epileptiform discharges after cathodal tDCS (Karvigh et al, 2017 ). Indeed, in a pediatric clinical study conducted by Varga et al ( 2011 ) in five children suffering from refractory continuous spike and waves during slow sleep, they found no reduction of spike-index and they assigned this result to the use of smaller tDCS electrodes than those usually used in conventional tDCS.…”

Transcranial direct current stimulation (tDCS) in the management of epilepsy: A systematic review

“…1. Therefore, 27 original studies met inclusion criteria and were included in this systematic review, comprising nine original sham-controlled trials [20][21][22][26][27][28][29][30][31] (Table 1) and 18 uncontrolled trials and case series/reports [32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] (Tables 2 and 3). Overall, studies encompassed 328 people with epilepsy of whom 253 underwent active stimulation while 75 received sham intervention.…”

“…Despite different time lengths and stimulation spots, both found a remarkable reduction in seizure frequency. Lastly, POLG-related mitochondrial disease was also targeted for tDCS stimulation by Ng et al [45] and Marquardt et al [47] In the former study, temporary improvements on seizure frequency were only seen during tDCS, returning to baseline levels after stimulation. On the other hand, the latter study did not show any effects of active tDCS neither in seizure frequency nor IEDs.…”