Development of temporal lobe epilepsy during maintenance electroconvulsive therapy: A case of human kindling?

Abstract

Summary We describe a patient with new‐onset temporal lobe epilepsy during prolonged maintenance electroconvulsive therapy. We suggest a possible causal relationship with maintenance electroconvulsive therapy through electrical kindling of the temporal lobe.

Tardive Seizures After Electroconvulsive Therapy

“…In any case, kindling in humans remains speculative, with higher-order animal models not only suggesting that humans may be resistant to kindling but also demonstrating inhibition of kindling with ECT type stimulation. 11,[47][48][49] Tardive seizures may instead result from a failure of the "normal" postictal seizure suppression, thought to be controlled by thalamocortical pathways. 18 Postictal EEG recordings typically demonstrate delta wave slowing or total suppression of background activity, the duration of which is variable.…”

“…No tardive seizure episode occurred after an unsuccessful or subconvulsive stimulus, in which the phenomena of “kindling” could be considered. In any case, kindling in humans remains speculative, with higher-order animal models not only suggesting that humans may be resistant to kindling but also demonstrating inhibition of kindling with ECT type stimulation 11,47–49 . Tardive seizures may instead result from a failure of the “normal” postictal seizure suppression, thought to be controlled by thalamocortical pathways 18 .…”

Commentary on Schotte et al. “Development of temporal lobe epilepsy during maintenance electroconvulsive therapy: A case of human kindling?”

“…This may be due, in part, to the greater number of stimulations needed to elicit kindling, the higher the animal is on the phylogenetic scale. 5 Schotte et al 21 presented a 67-year-old right-handed woman with no family history of epilepsy or febrile seizures, who had been receiving electroconvulsive therapy (ECT) sessions for medically refractory bipolar disease. She received weekly bilateral temporal ECT for 9 years before being switched to right temporal ECT (weekly initially; then reduced to every other week), due to concerns of cognitive deterioration.…”

“…Furthermore, pre-ECT data on neuroimaging or video-EEG monitoring to determine preexisting pathologies at the contralateral site are missing. The chronic concomitant use of valproate or benzodiazepines for the treatment of psychiatric disorders in some of these patients, 21,25 may have masked or delayed the onset of the clinical manifestations of prior epilepsy. On the contrary, could the unilateral ECT have protected the ipsilateral temporal lobe from injury or propensity to manifest or sustain ictal activity?…”

“…On the contrary, could the unilateral ECT have protected the ipsilateral temporal lobe from injury or propensity to manifest or sustain ictal activity? 21,24,25 Electroconvulsive seizures result in a period of postictal refractoriness to seizures or epileptic activity 26,27 that may contribute to apparent antiseizure effects. Bilateral ECT has been used to stop superrefractory status epilepticus, [28][29][30] although most studies have been retrospective or case reports, thus warranting further confirmation with prospective studies before recommending its use.…”