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bioRxiv · 10.1101/2025.09.19.677437

Elevated Thalamic Blood Flow in Self-Limited Epilepsy with Centrotemporal Spikes

Abstract

Children with self-limited epilepsy syndrome with centrotemporal spikes (SeLECTS) exhibit altered thalamocortical connectivity, but whether thalamic function itself is abnormal remains unclear. We investigated whether thalamic blood flow, a marker of metabolism, differs between children with SeLECTS and controls, and examined the effects of spike distribution and antiseizure medications (ASMs) on thalamic perfusion. In this retrospective cohort study, we identified consecutive children with SeLECTS who underwent magnetic resonance imaging (MRI) for epilepsy evaluation (n = 44) and age- and sex-matched children who underwent MRI for non-epilepsy indications (n = 35). We quantified thalamic blood flow via manual segmentation of cerebral blood flow (CBF) sequences obtained from arterial spin labeling MRI. Clinical variables including sedation use during MRI, daily ASM use, and spike distribution (unilateral or bilateral) were extracted from medical records. Children with SeLECTS demonstrated elevated thalamic blood flow compared to controls, with the most pronounced differences in specific subgroups. Children with unilateral spikes showed the highest CBF, particularly in the thalamus contralateral to spike activity. ASM use significantly modulated thalamic blood flow: children taking oxcarbazepine showed the highest CBF, while those on levetiracetam had CBF similar to controls. Unmedicated children showed intermediate elevations. These findings demonstrate that elevated thalamic blood flow may be intrinsic to SeLECTS pathophysiology, with different ASMs producing distinct neurobiological effects. The differential medication effects may relate to their clinical efficacy and provide neurobiological rationale for treatment selection in this common childhood epilepsy syndrome.

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BibTeXRIS

Iasinovschi, N., Tong, E., Bicknell, L., Baumer, F. M.. 2025-09-20. Elevated Thalamic Blood Flow in Self-Limited Epilepsy with Centrotemporal Spikes. https://doi.org/10.1101/2025.09.19.677437

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