수평사위 군에서 수직동향프리즘의 영향에 관한 연구

A Study on the Influence of Vertical Yoked Prism in Horizontal Group

Background: The study aimed to investigate the effects of vertical yoked prisms on perceptual adaptation in horizontal. Methods: The study was conducted on 20 individuals (12 males, 8 females) with horizontal phoria, who had no ocular diseases. The participants underwent objective refraction testing with an auto refractor (ARK, RK-8000, TOPCON, JAPAN) and subjective refraction testing, including fogging, with a phoropter (HDR-7000, HUVIZ, KOREA). The final full correction values were verified and applied using a retinoscope (Retinoscope, Welch Allyn, Germany). To prevent the influence of glasses-induced prism, disposable soft contact lenses were used for measurement. Prism measurements were taken in intervals of 40 minutes, followed by a 20-minute rest period. After measuring horizontal phoria, vertical prisms of 4 prism and 8 prism were added, and near and distance phoria, near point of accommodation, positive fusional convergence, and negative relative accommodation were measured. Results: The mean age of the participants was 22.72±2.84 years, and the spherical equivalent refractive power from the refractive test was -3.50±2.70 D. Binocular visual testing showed that the participants had an near point of accommodation 8.50 ± 1.23 cm, a distance horizontal phoria of 1.30±2.41 △ exophoria, and a near horizontal phoria of 4.50±2.83 △ exophoria. When an 8 prism base-down prism was added, there was a difference in the change of negative relative accommodation compared to when a 4 prism base-down prism was added. Conclusion: It was observed that when a vertical prism was added to a normal binocular visual with horizontal phoria, it had some impact on binocular visual and accommodative function, at least during the short-term adaptation period. Further research is needed to determine whether the use of vertical prisms affects accommodative function and other binocular visual functions.