Reduced thalamic volume in patients with Electrical Status Epilepticus in Sleep

Abstract

Purpose: To test whether patients with Electrical Status Epilepticus in Sleep (ESES) and normal neuroimaging have a smaller thalamic volume than expected for age and for total brain volume.

Methods: Case-control study comparing three groups of subjects of 4-14 years of age and normal magnetic resonance imaging: 1) ESES patients, 2) patients with refractory epilepsy control group, and 3) healthy controls. Thalamic and total brain volumes were calculated using an algorithm for automatic segmentation and parcellation of magnetic resonance imaging.

Results: Eighteen ESES patients, 29 refractory epilepsy controls and 51 healthy controls were included. The median (p25-p75) age was 8.8 (7.5-10.3) years for ESES patients, 11 (7-12) years for healthy controls, and 9 (6.3-11.2) years for refractory epilepsy controls. After correcting for total brain volume and age, the left thalamus was not statistically significantly smaller in ESES patients than in healthy controls (p=0.077), in ESES patients than in refractory epilepsy controls (p=0.056); but the right thalamus was smaller in ESES patients than in healthy controls (p=0.044), and in ESES patients than in refractory epilepsy controls (p=0.033).

Conclusion: Patients with ESES and normal magnetic resonance imaging have smaller relative thalamic volume controlling for age and total brain volume.

Keywords: Case-control study; Epilepsy; Neurophysiology; Seizures; Volumetric magnetic resonance imaging.