pASL versus DSC perfusion MRI in lateralizing temporal lobe epilepsy

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Accurate lateralization of the epileptogenic focus is critical for temporal lobe epilepsy (TLE) management.
• Pulsed arterial spin labeling (pASL) quantifies relative cerebral blood flow (rCBF) by measuring arterial blood inflow.
• pASL is a potential tool for presurgical evaluation in refractory TLE.

Purpose of the Study:

• To assess pASL's ability to detect mesial temporal lobe (mTL) perfusion asymmetry in refractory TLE patients.
• To compare pASL with dynamic susceptibility contrast enhanced (DSC) MRI for lateralizing the epileptogenic focus.
• To evaluate perfusion asymmetry for epilepsy lateralization.

Main Methods:

• 36 patients with refractory TLE and 11 healthy volunteers underwent 3T brain MRI.
• pASL and DSC perfusion imaging were performed on all subjects.
• Relative cerebral blood flow (rCBF) and asymmetry index (AI) were calculated and compared with clinical lateralization.

Main Results:

• No significant difference in rCBF ratios between pASL and DSC in healthy volunteers.
• TLE patients showed significantly lower rCBF on the ipsilateral (affected) side compared to the contralateral side using both techniques.
• High correlation found between clinical laterality and perfusion AI (0.86 for pASL, 0.83 for DSC).

Conclusions:

• pASL successfully detects interictal perfusion asymmetry in TLE patients.
• pASL can be integrated with structural MRI for epilepsy lateralization.
• pASL provides a valuable alternative to DSC perfusion imaging.