외사시와 정상 소아 환자에서 펜타캠을 이용한 람다각의 측정 = Measurement of Angle Lambda Using Pentacam in Normal and Exotropic Children

국문 초록 (Abstract)

목적: 소아 외사시환아와 정상환아에서 펜타캠(Pentacam HR, Oculus, Wetzler, Germany)을 이용하여 람다각을 측정하고 굴절이상과의 관계를 알아보았다.
대상과 방법: 2013년 12월 9일부터 2014년 8월 5일까지 본원 안과에 내원한 16세 미만의 환자 135명의 135안(정상안 70안, 외사시안 65안)을 대상으로 펜타캠을 이용하여 동공중심과 각막반사점 간의 거리를 측정, 코사인 제2 법칙을 이용하여 람다각으로 환산한 결과와 구면대응치, 연령, 안축장 등의 변수를 분석하였다.
결과: 대상 집단은 남자 70명, 여자 65명이고 평균 연령은 7.6 ± 3.7세였다. 평균 람다각은 4.66 ± 2.41o, 구면대응치는 -0.39 ± 2.39였다. 정상안과 외사시안으로 분류하였을 때, 람다각은 4.41 ± 2.23o, 4.92 ± 2.58o, 구면대응치는 -0.64 ± 2.69D, -0.11 ± 2.00D로 통계적으로 유의한 차이는 없었다. 근시, 정시, 원시안으로 분류하였을 때, 람다각은 3.95 ± 2.16o, 4.84 ± 2.62o, 5.30 ± 2.35o였다. 람다각은 구면대응치와 양의 상관관계를 보였다(상관계수=0.341, p＜0.001). 연령과 람다각 간에는 음의 상관관계가 있었고(상관계수=-0.181, p=0.036), 안축장과 람다각은 음의 상관관계가 있었다(상관계수=-0.469, p=0.003).
결론: 펜타캠을 이용한 람다각 측정 결과는 기존의 연구 결과와 일치하는 경향을 보였다. 펜타캠을 통한 람다각 측정은 소아에서 신속하고 재현 가능하며 정량적, 객관적인 방법으로 추천될 수 있겠다.

다국어 초록 (Multilingual Abstract)

Purpose: We measured angle lambda in normal and exotropic patients using Pentacam HR (Oculus, Wetzler, Germany). The relationship between angle lambda and refractive error was analyzed in the present study.
Methods: From December, 2013 to August, 2014, 135 eyes of 135 individuals under 16 years of age were enrolled in this study. Pentacam measures a distance between the center of the pupil and the corneal reflex point. The distance was converted to the angle lambda using the second law of cosines. All statistical analyses were performed using SPSS for Windows, version 21.0 (SPSS Inc, Chicago, IL, USA). The differences among the groups when measuring angle lambda were calculated using in-dependent t-test, Mann-Whitney test and analysis of variance (ANOVA). Pearson's correlation test was used to analyze the cor-relation among the variables.
Results: The mean age was 7.60 ± 3.68 years. Mean angle lambda values of the normal and exotropia groups were 4.41 ± 2.23°and 4.92 ± 2.58°, respectively. To evaluate the association of angle lambda and refraction measures, individuals were further classified according to the degree of myopia and hyperopia. The angle lambda values in the 3 groups according to refraction sta-tus (myopic, emmetropic and hyperopic) were 3.95 ± 2.16°, 4.84 ± 2.62° and 5.30 ± 2.35°, respectively. A positive correlation was observed between angle lambda and spherical equivalent (correlation coefficient = 0.341, p < 0.001). A significant negative correlation was observed between angle lambda and age (correlation coefficient = -0.181, p = 0.036). There was a negative cor-relation between axial length and angle lambda (correlation coefficient = -0.469, p = 0.003).
Conclusions: The results in this study were in agreement with the results from previous studies. Measuring the distance between the centers of the pupil and the point of corneal reflection using Pentacam is recommended as a quick, objective, quantitative and reproducible method to measure the angle lambda in children.

목차 (Table of Contents)

• Abstract
• 대상과 방법
• 결과
• 고찰
• 국문초록

참고문헌 (Reference)

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