Background: Temporal lobe epilepsy (TLE) is the most prevalent localized condition associated with epilepsy syndrome and is often unresponsive to any medical treatment.
Objectives: This study aimed to assess the role of diffusion tensor imaging (DTI) and diffusion tensor tractography in the evaluation of TLE patients.
Patients and methods: This study was included 40 TLE patients were clinically diagnosed by a neurologist as TLE, either due to hippocampal sclerosis or other organic cause and were included if they had a seizure-free-period for one week before the radiological assessment. Twenty healthy volunteers as a control.
Results: The mean fractional anisotropy (FA) of the studied white matter tracts was significantly lower in the patient than in the control group (P<0.001). The DTI parameters showed agreement with the conventional MRI findings in 26 patients (65.0%). However, the present study revealed that DTI parameters were affected among the 14 patients (35%) with normal conventional MRI. Studying the association between the degree of FA reduction and some clinical factors (age at onset of the seizure, disease duration, and seizure frequency) was carried out. The degree of FA reduction was positively correlated with the duration of the disease and seizure frequency and negatively correlated with age at the onset of epilepsy. There was a significant correlation between FA reduction and the disease duration (r=0.333, P=0.036).
Conclusion: DTI parameters and MRI tractography are new structural imaging methods that provide sensitive markers to early identify and lateralize hippocampal abnormalities in TLE patients, particularly in patients with negative conventional MRI.