Global Pediatric Ophthalmology Congress

Biography

Biography: Igor Aznauryan

Abstract

Introduction: Resilience of the amblyopia to its treatment in children with astigmatism necessitates a further study of the features of this disease. The purpose of the investigation is to study the specificity of the responseof the cerebral cortex and the mechanisms of the perceiving disorders in children with astigmatism. Methods: We used VEP generated in response to a reversion of black and white stripes with rectangular illumination profile to study cerebral cortex response. The size of rectangular stripes corresponded to maximally corrected visual acuity under the condition of full optical correction. The peculiarity of this technique is that the stripes are dimensionally oriented in the direction of the main astigmatism meridians of the amblyopic eye. Amplitude P100, which was obtained in main meridians, was investigated and compared. Visual acuity was investigated in main meridians. Correlation between amplitude P100 and visual acuity in similar meridians was analyzed. Results: We noted a significant difference in amplitude P100 when the reversible stripes were localized in main meridians. This meridional asymmetry correlates with different visual acuity, obtained in different meridians. The difference in amplitude P100 in meridians doesn't depend on the type and the extent of astigmatism. Discussion: We have obtained a particular response from the cerebral cortex in patients with astigmatism. This allows to suggest that amblyopia in patients with astigmatism develops in a specific manner - afferent signals from retina cells, sending information about dimensional localization, are perceived by the cortex unequally. So, information coming from the receptive field of the meridian which has preferred optics (with focus located closer to retina) is perceived better. We have also discovered that the type of astigmatism significantly influences the mechanism and the extent of amblyopia development. It was also noted that meridional asymmetry appears in patients even with insignificant level of astigmatism (1.5 dptr and more). Conclusion: Information obtained allows for more in-depth appreciation of the mechanism of the amblyopia development in patients with astigmatism. This circumstance makes possible to develop new, more effective ways of amblyopia treatment in patients with astigmatism. It also allows identifying a new criterion for the successful amblyopia treatment in patients with astigmatism - an absence of meridional asymmetry when conducting VEP using method described above.