Pattern Visual Evoked Potential, Pattern Electroretinogram, and Retinal Nerve Fiber Layer Thickness in Patients with Migraine during and after Aura.

PURPOSE

To study pattern visual evoked potential (PVEP), pattern electroretinogram (PERG), and retinal nerve fiber layer (RNFL) thickness in patients with migraine during and after aura.

MATERIALS AND METHODS

We included 60 eyes of 60 patients with migraine (Group 1) and 30 healthy volunteers (30 eyes) as controls (Group 2). Group 1 was studied twice, during a visual aura (1-a) and in between attacks (1-b). All participants underwent full ophthalmological examination, PVEP, PERG, and optical coherence tomographyOCT imaging of the RNFL thickness for each patient.

RESULTS

RNFL thickness was found to be thinner in patients during the aura compared to controls. It increased significantly post-aura but remained lower than the controls. Prolonged P100 latency and decreased amplitude were found in patients during aura compared to controls with significant change in between attacks to values comparable to the controls. We found prolonged N95 latency and decreased amplitude in patients during aura compared to controls with significant change post-aura to values comparable to the controls. There was positive correlation between average RNFL thicknesses and VA and spherical equivalent; but it showed negative correlation with duration of migraine, attack duration, and aura duration. Multiple regression analysis showed that the most important determinants of average RNFL thickness in patients of migraine were attack and aura duration (beta = -0.21 and -0.26 and p = 0.03 and 0.04, respectively).

CONCLUSION

Migraine attacks impose both functional and structural retinal changes. The functional changes are fully reversible after the aura but not the structural ones. So, vigorous prevention of migraine attacks would be protective for retina.