Do myopes have deficits in peripheral flicker sensitivity?

• Amithavikram R. Hathibelagal ^[1] ; Manoj K. Manoharan ^{[1] [2]} ; Pavan K. Verkicharla ^{[1] [2]}
  1. [1] Brien Holden Institute of Optometry and Vision Sciences, Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Road No. 2, Banjara Hills, Kallam Anji Reddy Campus, Hyderabad 500034, India
  2. [2] Myopia Research Lab – Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
• Localización: Journal of Optometry: peer-reviewed Journal of the Spanish General Council of Optometry, ISSN-e 1888-4296, Vol. 15, Nº. 2, 2022, págs. 138-144
• Idioma: inglés
• Enlaces
  • Texto completo
• Resumen

  • Purpose Signals from the peripheral retina are important for myopia development. Unlike temporal vision, deficits in peripheral spatial visual functions of myopes have been investigated previously. This study investigated temporal contrast thresholds in emmetropes and myopes at different retinal eccentricities.

    Methods Forty-four young adults (mean age 23 ± 3 years) including 21 emmetropes (Spherical Equivalent (SE): +0.01 ± 0.30D) and 23 myopes (SE: -3.98 ± 2.41D) participated in this prospective study. Flicker modulation thresholds (FMT) were determined monocularly (right eye) for 15 Hz flicker stimulus at 0°, nasal (23°, 10°) and temporal (-23°, -10°) retinal eccentricities along the horizontal meridian. FMTs were measured psychophysically using 5-adaptive interleaved staircases and threshold was taken as the average of the last 6 reversals.

    Results In both the groups (emmetropes and myopes), there was a naso-temporal asymmetry in FMTs with higher thresholds in the far temporal retina (Median; Interquartile range: 40.97%; 17.06) than the nasal retina (28.07%; 9.36) (p < 0.001). Flicker modulation thresholds were significantly higher in myopes (30.58%; 12.15) compared to emmetropes (26.77%; 7.74; p = 0.04) at far nasal retina (23°), while at other eccentricities there was no effect (p > 0.05). Further sub-analysis revealed only high myopes (34.48 %, 21.9) showed significantly higher FMT compared to emmetropes (26.77%; 7.74; p = 0.04).

    Conclusion Greater FMTs were seen in high myopes than that of emmetropes in the nasal retina. Further studies exploring the structural aspects of the myopic eye with FMT would provide a better understanding of role of flicker sensitivity in myopiogenesis.