Correlative Study between Magnetic Resonance Imaging (MRI) Findings and Interictal Spike Rate in Patients with Refractory Temporal Lobe Epilepsy

Interictal spikes not only are used to diagnose epilepsy, its syndromes, and therapeutic guidelines in patients with epilepsy, but also may be a window to understand anatomy, severity, and epilepsy outcomes better. The aim of this study was to investigate the relationship between interictal spike rate and magnetic resonance imaging (MRI) findings.

This descriptive cross-sectional study was performed on patients with refractory temporal lobe epilepsy admitted to epilepsy monitoring unit, Ayatollah Kashani hospital, Isfahan, Iran. Brain MRI (with epilepsy protocol) and all files related to long-term monitoring (LTM) of patients were studied, and then, the spike rate was calculated for each patient. Clinical information of patients as well as MRI and interictal findings were placed in separate tables designed for this purpose. Analysis of these findings consisted of two parts. In the first part, descriptive statistics (frequency and percentage), and for second part, inferential statistics (Spearman correlation coefficient and multivariate logistic regression) were used.

This study was done on 70 patients with refractory temporal lobe epilepsy, 44 men (62.9%) and 26 women (37.1%). The mean age of the participants was 29.00 ± 10.49 years (10-60). Spearman's correlation coefficient showed a significant relationship between spike rate and MRI findings (P < 0.050). The results of regression analysis showed that only two lesions of "Hippocampus and Amygdala sclerosis" and "tumor and tumor-like lesions" could predict spike rate among MRI lesions. Normal MRI could also predict the amount of spikes.

 It seems that a combination of brain MRI with physiological measurements, including interictal spike rate, can determine subtypes of refractory temporal lobe epilepsy, and can lead to better diagnosis and treatment.</div>