Comparative Lateralizing Ability of Multimodality MRI in Temporal Lobe Epilepsy.

Area of Science:

• Neuroimaging
• Epilepsy Research
• Quantitative MRI

Background:

• Temporal lobe epilepsy (TLE) is a common neurological disorder.
• Accurate lateralization of the epileptogenic focus is crucial for surgical planning.
• Quantitative MRI (qMRI) offers potential for characterizing hippocampal changes in TLE.

Purpose of the Study:

• To compare the lateralizing ability of three qMRI modalities: volumetry, MR spectroscopy (MRS), and diffusion tensor imaging (DTI).
• To assess the capacity of these modalities to depict hippocampal architectural changes related to clinical TLE.
• To evaluate the diagnostic accuracy of combined qMRI techniques for lateralizing the seizure focus.

Main Methods:

• Evaluated 14 TLE patients and 15 healthy controls.
• Acquired T1-weighted 3D datasets for volumetry, single-voxel 1H MRS, and DTI for bilateral hippocampi.
• Analyzed volumetric measurements, spectroscopy data (NAA/(Cho+Cr)), and DTI metrics (FA, ADC).

Main Results:

• Individual volumetry achieved 85% lateralization accuracy; MRS and DTI achieved 57% each.
• Combined volumetry-DTI yielded 100% lateralization accuracy.
• Ipsilateral hippocampi showed decreased NAA/(Cho+Cr) and increased FA. Epilepsy duration correlated negatively with FA. Febrile convulsions correlated with increased ADC and reduced NAA/(Cho+Cr).

Conclusions:

• Volumetry, MRS, and DTI provide complementary information on hippocampal pathology in TLE.
• The combination of volumetry and DTI demonstrates high diagnostic accuracy for lateralizing the epileptogenic focus.
• Volumetry-DTI is a promising approach for preoperative assessment in TLE.