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Published on: August 5, 2014
Distinct patterns of hippocampal subfield volume loss in left and right mesial temporal lobe epilepsy
Hossein Sanjari Moghaddam1, Mohammad Hadi Aarabi1, Jafar Mehvari-Habibabadi2
1Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Objective:
To investigate the pattern and severity of hippocampal subfield volume loss in patients with left and right mesial temporal lobe epilepsy (mTLE) using quantitative MRI volumetric analysis.
Methods:
A total of 21 left and 14 right mTLE subjects, as well as 15 healthy controls, were enrolled in this cross-sectional study. A publically available magnetic resonance imaging (MRI) brain volumetry system (volBrain) was used for volumetric analysis of hippocampal subfields. The T1-weighted images were processed with a HIPS pipeline.
Results:
A distinct pattern of hippocampal subfield atrophy was found between left and right mTLE patients when compared with controls. Patients with left mTLE exhibited ipsilateral hippocampal atrophy and segmental volume depletion of the Cornu Ammonis (CA) 2/CA3, CA4/dentate gyrus (DG), and strata radiatum-lacunosum-moleculare (SR-SL-SM). Those with right mTLE exhibited similar ipsilateral hippocampal atrophy but with additional segmental CA1 volume depletion. More extensive bilateral subfield volume loss was apparent with right mTLE patients.
Conclusion:
We demonstrate that left and right mTLE patients show a dissimilar pattern of hippocampal subfield atrophy, suggesting the pathophysiology of epileptogenesis in left and right mTLE to be different.
Insights
Left and right mesial temporal lobe epilepsy (mTLE) show distinct patterns of hippocampal subfield atrophy. This MRI study reveals differing volume loss in specific hippocampal subfields, suggesting unique disease mechanisms.
Area of Science:
- Neuroimaging
- Epilepsy Research
- Neuroanatomy
Background:
- Mesial temporal lobe epilepsy (mTLE) is a common epilepsy syndrome.
- Hippocampal atrophy is a hallmark of mTLE.
- Understanding laterality-specific patterns of atrophy is crucial for diagnosis and treatment.
Purpose of the Study:
- To investigate the pattern and severity of hippocampal subfield volume loss in patients with left and right mTLE.
- To compare these patterns with healthy controls using quantitative MRI.
- To explore potential differences in epileptogenesis based on mTLE laterality.
Main Methods:
- Cross-sectional study including 21 left mTLE, 14 right mTLE, and 15 healthy controls.
- Quantitative MRI volumetric analysis of hippocampal subfields using the volBrain system.
- T1-weighted images processed with a HIPS pipeline.
Main Results:
- Distinct patterns of hippocampal subfield atrophy were observed between left and right mTLE patients compared to controls.
- Left mTLE showed ipsilateral atrophy in Cornu Ammonis (CA) 2/CA3, CA4/dentate gyrus (DG), and strata radiatum-lacunosum-moleculare (SR-SL-SM).
- Right mTLE exhibited similar ipsilateral atrophy with additional CA1 volume depletion and more extensive bilateral subfield loss.
Conclusions:
- Left and right mTLE patients demonstrate dissimilar patterns of hippocampal subfield atrophy.
- These findings suggest potentially different pathophysiological mechanisms underlying epileptogenesis in left versus right mTLE.
