Optical coherence tomography parameters in patients with photosensitive juvenile myoclonic epilepsy

Juvenile myoclonic epilepsy (JME) is commonly associated with photoparoxysmal response (PPR) with a reported prevalence of 25-42%. In this study, we aim to explore the relationship between the PPR and Optical Coherence Tomography (OCT) parameters in order to determine whether optic nerve fiber layer or other structural differences have a pathophysiological role of photosensitivity in patients with JME.

We studied 53 consecutive patients with Juvenile myoclonic epilepsy (JME) at our outpatient department. The interictal electroencephalogram (EEG) findings for each patient were analyzed for the presence of photoparoxysmal features. The peripapillary Retina Nerve Fiber Layer (RNFL) thickness, ganglion cell thickness, macular thickness and choroid thickness levels were analyzed using OCT.

We classified the patients into two groups as those with PPR (Group 1) and those without PPR (Group 2). There were statistically significant differences in the average RNFL thickness values of the left eye between the two groups (p<0.001). Although the RNFL thickness of the right eye was higher in Group 1, no statistically significant difference was observed between the two groups. The RFNL thickness of the superior quadrants both in the right and the left eyes was significantly higher in Group 1 patients (p<0.001). Macular thickness of the right and left eyes were significantly thinner in Group 1 patients (p<0.001). Choroid thickness of the left eye was significantly higher in Group 1 than in Group 2 patients (p<0.001). Although the choroid thickness of the right eye was higher in Group 1 patients, no statistically significant difference was observed between the two groups.

This is the first study to our knowledge which has investigated the relation between the OCT parameters and photosensitivity in patients with JME. We concluded that these microstructural features may be related to photosensitivity in patients with JME.