A Comparative Study on the Effects of Wearing Reverse Geometry Lenses by Degrees of Myopia

근시정도에 따른 역기하렌즈 착용효과에 관한 비교 연구

  • Yoon, Min-Hwa (Dept. of Biomedical Engineering, Chonnam University) ;
  • Lee, Ki-Young (Dept. of Optometry and Optic Science, Dongkang College)
  • Received : 2012.07.31
  • Accepted : 2012.09.15
  • Published : 2012.09.30

Abstract

Purpose: To compare the results on myopia correction with reverse geometry lenses, effects of wearing reverse geometry lenses were evaluated for the children with low-level and high-level myopia. Methods: The research investigated the corrective effects of having worn reverse geometry lenses for one week, one month, three months and six months on a total of thirty-six persons (sixty-two eyes) between the ages of seven and fifteen, divided into three groups by the degree of their myopia; nineteen eyes(Group One) with myopia of -2.00 D and under, twenty-eight eyes(Group Two) with myopia between -2.25 D and -4 D, and fifteen eyes(Group Three) with myopia of -4.25 D and above; as shown by changes in uncorrected vision and the degree of refraction in the corneal topography, and tested for statistical similarity among the pursued results. Results: After wearing reverse geometry lenses, Group One showed an improvement in vision of 0.5, from 0.45 to 0.95, after one week, and improvements to 0.91 after one month and 1.02 after three months but, after six months, the group's vision regressed to 0.95. Group Two showed an improvement in vision of 0.43, from 0.34 to 0.77, after one week of wearing and to 0.91 after one month, to 0.97 after three months and this was statistically maintained through the remainder of six months. Group Three showed an improvement in vision of 0.55, from 0.15 to 0.7, after wearing for one week, to 0.87 after one month and to 0.91 after three months but saw a regression to 0.86 after six months. The average Sim K (simulated keratometry reading) value for Group One started from $42.84{\pm}1.17D$ and decreased to $41.48{\pm}0.98D$ after one week of wearing and continued declining through three months before increasing during the remainder of six months. Group Two began from $42.91{\pm}1.57D$ and recorded $41.78{\pm}1.58 D$ after one week, continuing the decline through three months before increasing during the remainder of six months. Group Three began at $42.64{\pm}1.64D$ and showed its Sim K value decrease to $40.77{\pm}1.20D$ after one week of wearing, increase after one month and decrease after three months and continue the decline through the remainder of six months. Conclusions: From the results of this study, wearing reverse geometry lenses had myopia-correcting effects after one week of wearing. Although there were variations in the time for such effect to take place but myopia-correcting effects were evident in all test groups.

목적: 약도의 근시를 가진 아동과 중등도 이상의 근시를 가진 아동을 대상으로 역기하렌즈를 착용시키고 난 후의 근시교정효과를 비교하여 알아보고자 한다. 방법: 7세에서 15세 사이의 -2.00 D이하 근시안 19안(Group 1)과 -2.25 D이상에서 -4.00 D이하의 근시안 28안(Group 2), -4.25 D이상에서 근시안 15안(Group 3), 총 31명(62안)을 대상으로 역기하렌즈 착용 전, 착용 후 1주일, 1개월, 3개월, 6개월 후의 나안시력과 각막지형도상의 굴절력 변화를 근시의 정도에 따라 3그룹으로 나눠 교정효과를 알아보고 이에 대한 추적 결과의 통계적 유의성을 검증하고자 하였다. 결과: 역기하렌즈를 착용하고 난 후 Group 1은 착용 후 1주일에 시력이 0.45 에서 0.95 로 0.50 향상되었으며 1개월째 0.91, 3개월째 1.02 로 향상되었으나 6개월째 0.95 로 다시 감소하였다. Group 2는 착용 후 1주일에 시력이 0.34 에서 0.77 로 0.43 향상되었으며, 1개월째 0.91 로 증가되었으며, 3개월째 0.97 시력까지 향상되어 6개월까지 통계적으로 지속되었다. Group 3은 착용 후 1주일에 시력이 0.15 에서 0.70 로 0.55 향상되었으며, 1개월째 0.87, 3개월에는 0.91 로 향상되었으나 6개월째 0.86 으로 다시 감소되었다. 각막지형도상 평균 Sim K(simulated keratometry reading)값은 Group 1이 $42.84{\pm}1.17D$에서 착용 후 1주일에 $41.48{\pm}0.98D$로 감소하였으며 3개월까지 감소하다가 6개월에는 증가하였다. Group 2는 $42.91{\pm}1.57D$에서 착용 후 1주일에 $41.78{\pm}1.58D$로, 3개월까지는 감소하다가 6개월에 증가하였다. Group 3은 $42.64{\pm}1.64D$에서 $40.77{\pm}1.20D$로 착용 후 1주일에는 감소하였고 1개월 후에 다시 증가하였다가 3개월에 감소하여 6개월까지 감소하였다. 결론: 본 연구 결과 역기하렌즈의 착용 후 1주일부터 근시교정효과가 있었으며 근시정도에 따라 그 효과 발생 시기는 차이가 있었으나 모든 그룹에서 근시교정효과가 나타났음을 알 수 있었다.

Keywords

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