전체각막곡률측정법과 표준각막곡률측정법을 이용한 인공수정체도수 예측의 정확도 비교

Accuracy of Intraocular Lens Power Calculations Based on Total and Standard Keratometry

목적: Barrett Universal II 공식과 Barrett Toric Calculator에 전체각막곡률측정법과 표준각막곡률측정법을 적용하였을 때의 굴절예측 정확도를 비교해보고자 하였다. 대상과 방법: 백내장수술을 위해 본원을 내원한 환자 111명 111안을 대상으로 하였다. 수술 전 IOL Master 700？？ (Carl Zeiss Meditech AG, Jena, Germany)으로 Barrett Universal II 공식 또는 Barrett Toric Calculator를 사용한 굴절예측치와 수술 후의 현성굴절검사값을 이용하여 평균절대오차를 구하였다. 난시교정인공수정체를 넣은 대상 중 각막후면난시가 0.3 diopters (D)보다 큰 그룹을 분류하여 두 방법의 평균절대오차를 비교했다. 결과: Barrett Universal II 공식, Barrett Toric Calculator의 경우 구면렌즈대응치에 대해 전체각막곡률측정법과 표준각막곡률측정법의 평균절대오차의 차이는 각각 0.021 ± 0.102 D (p=0.65), 0.015 ± 0.121 D (p=0.80)였다. 난시교정인공수정체를 넣은 대상 중 후면각막난시가 0.3 D보다 큰 경우 구면렌즈대응치와 난시에 대한 평균절대오차 차이는 각각 -0.020 ± 0.107 D (p=0.70), -0.023 ± 0.055 D (p=0.50)였다. 결론: 전체각막곡률측정법은 표준각막곡률측정법과 비슷한 굴절예측 결과를 보였고, 난시교정인공수정체를 삽입했을 때 후면각막난시가 큰 경우에도 전체각막곡률측정법이 표준각막곡률측정법에 비해 통계적인 차이를 보이지 않았다.

Purpose: To compare the accuracy of standard and total keratometry data obtained using the Barrett Universal II and Barrett Toric Calculator. Methods: In total, 111 eyes of 111 patients who visited our hospital for cataract surgery from February 2019 to September 2019 were included in this study. Total keratometry and standard keratometry data were obtained using the Barrett Universal II and the Barrett Toric Calculator; mean absolute errors were derived by using preoperative IOL Master 700？？ (Carl Zeiss Meditech AG, Jena, Germany) data and 2-month postoperative manifest refraction data. The mean absolute errors of the two methods were compared in terms of a posterior corneal astigmatism greater than 0.3 diopter (D) in patients fitted with Toric intraocular lenses. Results: Using the Barrett Universal II formula, the mean absolute error spherical equivalent difference between total keratometry and standard keratometry was 0.021 ± 0.102 D (p = 0.65) when the Barrett Toric Calculator was used. The mean absolute error differences between the two methods were 0.015 ± 0.121 D for the spherical equivalent (p = 0.80) and 0.005 ± 0.870 D for the cylinder measurement (p = 0.94). In terms of a posterior corneal astigmatism greater than 0.3 D, the mean absolute error spherical equivalent and cylinder measurement differences were -0.020 ± 0.107 D (p = 0.70) and -0.023 ± 0.055 D (p = 0.50) in patients fitted with Toric intraocular lenses. Conclusions: The total keratometry method, which directly measures posterior corneal curvature, yields data comparable to those of the standard keratometry method. When the posterior corneal astigmatism was greater than 0.3 D, we found no significant difference between the total keratometry and standard keratometry data of patients fitted with Toric intraocular lenses.