A Study of Hippocampal T2 Relaxometry Value in Temporal Lobe Epilepsy Patient

Abstract

In the advancement of the current imaging technique for detection of mesial temporal sclerosis in temporal lobe epilepsy patient, there are multiple Magnetic resonance imaging (MRI) quantitative techniques. One of the long known to be valuable quantitative technique is T2 relaxometry where it has overall better accuracy for detection of mesial temporal sclerosis compared with the qualitative assessment only. A comparative cross-sectional study was conducted in Hospital Universiti Sains Malaysia from August 2021 to January 2023 which include 51 participants, 19 (36.5%) were temporal lobe epilepsy patient and 33 (63.5%) were control. The hippocampal T2 relaxometry was calculated for temporal lobe epilepsy patient and control. The mean T2 relaxometry reading for these groups were compared using Independent T-test. The correlation of T2 relaxometry value with age, duration of epilepsy and seizure frequency were analysed using Pearson correlation. Cohen Kappa inter-rater reliability was done for MR qualitative assessment. The participant age range was from 15 to 65 years old. Total of 23 samples were male (44.2%). The mean T2 relaxometry for epilepsy patient was higher than control. For correlation, moderate to good positive correlation was seen between the duration of epilepsy with T2 relaxometry of right hippocampus. Whereas poor positive correlation between the right hippocampus T2 relaxometry with age (P>0.01), as well poor positive correlation between both hippocampus T2 relaxometry with seizure frequency (P>0.01). There was one patient (5.2%) reported to be negative for mesial temporal sclerosis by qualitative assessment, but the T2 relaxometry reading however was raised. As a conclusion, T2 relaxometry sequence can be use as adjunct to the current qualitative assessment to increase sensitivity and specificity in detecting mesial temporal sclerosis.
 Keywords: Temporal lobe epilepsy, Mesial temporal sclerosis, T2 relaxometry, MRI epilepsy protocol