Analysis of brain volume in hippocampal sclerotic temporal lobe epilepsy using automatic brain segmentation
Jin-Qin Li1, Jian Li2, Yan-Ling Zhang1
1School of Clinical Medicine, Ningxia Medical University, Yinchuan, China.
Background:
Abnormal discharges in epilepsy frequently result in alterations in brain volume. A quantitative analysis of brain volume in patients with epilepsy is essential for accurately identifying the epileptogenic zone, assessing the extent of damage, and predicting prognosis. This study aims to quantify the brain volume of patients with hippocampal sclerotic temporal lobe epilepsy using automated brain segmentation techniques, and to assess the impact of the disease on brain volume through a case-control approach.
Methods:
We analyzed magnetic resonance imaging data from 60 patients diagnosed with hippocampal sclerotic temporal lobe epilepsy, including 34 with left-sided hippocampal sclerotic temporal lobe epilepsy and 26 with right-sided hippocampal sclerotic temporal lobe epilepsy, alongside 35 healthy controls. The FreeSurfer software was used for whole-brain segmentation and the volume of some regions was measured, including temporal lobe subregions (posterior superior temporal gyrus, temporal pole, transverse temporal gyrus, superior temporal gyrus, middle temporal gyrus, inferior temporal gyrus), fusiform gyrus, parahippocampal gyrus, insula, amygdala, thalamus, and hippocampus. We compared brain volume differences between the left and right sides of the control group, the control group, and the left-sided hippocampal sclerotic temporal lobe epilepsy group, and between the affected and contralateral sides of the right-sided hippocampal sclerotic temporal lobe epilepsy group, the correlation between white matter volume and the course, frequency and duration of disease was analyzed.
Results:
Significant differences in brain volume were observed between the left and right sides of the control group (P<0.05). Compared with the control group, left-sided hippocampal sclerotic temporal lobe epilepsy (middle temporal gyrus: P=0.007; inferior temporal gyrus, fusiform gyrus, parahippocampal gyrus, hippocampus, thalamus: P<0.001) and right-sided hippocampal sclerotic temporal lobe epilepsy (middle temporal gyrus: P=0.008; thalamus: P=0.004; parahippocampal gyrus, hippocampus: P<0.001) patients had reduced brain volume on the affected side. Left-sided hippocampal sclerotic temporal lobe epilepsy patients exhibited more extensive and pronounced volume reductions. Except for the fusiform gyrus on the affected side of left-sided hippocampal sclerotic temporal lobe epilepsy showing a moderate negative correlation with the disease course (r=-0.517), most of the white matter in the other temporal regions showed a low negative correlation with the disease course. However, it has no correlation with the incidence frequency and duration of the disease.
Conclusions:
Hippocampal sclerotic temporal lobe epilepsy affects brain volumes differently depending on the epileptogenic focus location. This study demonstrates the utility of automatic brain segmentation technology in quantitatively assessing brain volume in hippocampal sclerotic temporal lobe epilepsy, more pronounced in left-sided hippocampal sclerotic temporal lobe epilepsy compared to right-sided hippocampal sclerotic temporal lobe epilepsy. This result provides valuable imaging data for the preoperative assessment, surgical planning, and prognosis of temporal lobe epilepsy.
