Comparison of Corneal Asphericity with Measuring Range

측정 범위에 따른 각막비구면계수의 비교

  • Received : 2012.11.05
  • Accepted : 2012.12.15
  • Published : 2012.12.31

Abstract

Purpose: The purpose of this study is to investigate the changes of asphericity according to diameter and direction of the cornea. Methods: The changes of asphericity according to diameter and direction of cornea is measured by using Pentacam(Oculus Co., Germany), as targeting 57 adults (average $27.0{\pm}4.8$, 20 men, 37 women) without any ophthalmic diseases, which may be effective in eyesight, and refractive surgery. Results: As diameter increases in every direction based on the corneal vertex, asphericity has attentively increased (p<0.05), and the size of asphericity in each direction from every measured diameter showed as superior > nasal > inferior > temporal. In group comparison by nearsightness and astigmatism level, asphericity measured high when nearsightness and astigmatism levels were higher, and this appears to be statistically attentive.(p<0.05). Conclusions: Asphericity of cornea significantly increased according to increase of diameter of cornea, and as measured figure or increased quantity appeared differently in all directions based on corneal vertex, so it helps to understand shape of cornea, and considered that is the part to be considered during manufacturing and fitting of RGP lenses.

목적: 본 연구의 목적은 각막의 직경과 방향에 따른 비구면계수 변화를 알아보고자 하였다. 방법: 시력에 영향을 줄 수 있는 안과적 질환이 없고 굴절교정 수술 경험이 없는 성인 57명(평균 $27.0{\pm}4.8$세, 남 20명, 여37명)을 대상으로 각막비구면계측기(Pentacam, Oculus Co., Germany)을 이용하여 각막의 직경과 방향에 따른 비구면계수 변화를 측정하였다. 결과: 각막정점을 기준으로 모든 방향에서 직경이 증가함에 따라 비구면계수가 통계적으로 유의하게 증가하였으며(p<0.05), 측정된 모든 직경에서 방향별 비구면계수의 크기는 상측> 비측> 하측> 이측 순으로 나타났다. 강주경선과 약주경선에 따른 비구면계수와 변화량은 강주경선에서 높게 측정되었으며 이는 통계적으로 유의한 것으로 나타났다(p<0.05). 결론: 각막의 비구면계수는 각막의 직경이 증가함에 따라 유의하게 증가하였고, 각막정점을 기준으로 모든 방향에서 측정된 수치나 증가량이 다르게 나타나므로 각막형상을 이해하는데 도움이 되고 RGP 렌즈 제조와 피팅시 고려되어야 할 부분이라 생각된다.

Keywords

References

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