• Title/Summary/Keyword: 크로스실린더법

Search Result 5, Processing Time 0.016 seconds

Repeatability of Monocular Spherical Endpoints Test (단안 구면 끝점검사의 반복성 검증)

  • Kim, Sang-Yeob;Moon, Byeong-Yeon;Cho, Hyun Gug
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.17 no.2
    • /
    • pp.209-213
    • /
    • 2012
  • Purpose: To assess the repeatability of the monocular spherical endpoints, a test was performed with four methods which are the retinoscopy, the MPMVA (maximum plus maximum visual acuity) method, the R/G duochrome method, and the crossed cylinder method. Methods: The monocular spherical endpoints was measured by four kinds of method (Retinoscopy, MPMVA method, R/G duochrome method, Crossed cylinder method) on 20 subjects (40 eyes) of average age 23.0 year-old men and women. After a week, retest was performed by same procedure and the test-retest repeatability was assessed by using the Bland-Altman plot analysis. Results: The test-retest mean difference of retinoscopy was the smallest diopters of -0.03 and that of R/G duochrome method was the largest diopters of -0.19. The upper/lower 95% limits of agreement for repeatability was the narrowest in retinoscopy and was the widest in crossed cylinder method. When compared the spherical endpoints of each eye between by retinoscopy and by other three methods, the error rate of ${\pm}0.25D$ in total eyes was 85% in MPMVA method, 80% in R/G duochrome method, and 24% in crossed cylinder method. Conclusions: Test-retest repeatability is the highest in the retinoscopy, and the retinoscopy, the MPMVA method, and R/G duochrome method are suitable for monocular spherical endpoints test.

A Clinical Study on Presbyopia in Wearing the Near Spectacle for the First Time (근용 안경을 최초 장용하는 노안에 대한 임상적 연구)

  • Yoo, Jong-Sook;Lim, Hyeon-Seon;Lee, Soo-Cheon;Hwang, Jung-Hee;Kim, Hyo-Jung
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.13 no.4
    • /
    • pp.103-107
    • /
    • 2008
  • Purpose: This research measured the near addition powers of presbyopia in wearing the near spectacle for the first time. Methods: We evaluated age, sex, working group, spherical power and cylindrical power and measured the power of refractive error performed the both eyes (310 eyes) of 155 subjects subjectively noncycloplegic and power of addition using the cross cylinder method. Results: There were measured the near addition powers in the range of +0.75D ~ +1.75D. In case of the average addition, they were measured with +1.06D in subjects under 43 years of age, +1.08D in 44 to 46 years, +1.23D in 47 to 49 years and +1.46D in over 50 years of age. The average age in subjects was 47.6 years old and 74 male, 81 female, 71 near sighted working group and 83 far sighted working group. Conclusions: Near addition was correlated with age, working group and cylindrical power (P<0.05, P<0.05, P<0.05).

  • PDF

Presbyopic Addition of Using Method of Cross Cylinder (크로스실린더 검사법을 이용한 노안의 근용 가입도)

  • Ryu, Geun-Chang
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.12 no.3
    • /
    • pp.71-75
    • /
    • 2007
  • This research was conducted from 1 March 2005 to 28 February 2007. We collected data from optician stores around Kwang-Ju city, 208 people aged 40 to 80 years using the cross cylinder method to find out age and gender dependence of near addition. 1. Age dependence of Refractive error shows 5% of emmetropia 34% of myopia and 43% of hyperopia. These results reveal that rate of hyperopia is higher than emmetropia and myopia. Mixed Astigmatism rate was 18%. 2. Near addition required to correct Presbyopia is analyzed as functions of gender and ages. In case of man: 40-44 (+0.75D), 45-49(+1.25D), 50-54(+1.41D), 55-59(+1.92D), 60-64(+2.35D), 65-69(+1.97D), 70(+3.12D), In case of woman: 40-44 (+1.08D), 45-49 (+1.38D), 50-54 (+1.67D), 55-59(+2.05D), 60-64 (+2.50D), 65-69 (+2.57D), $70{\leq}(+3.18D)$. Result shows it's Adding power higher than man. 3. Age dependence of Axis of Astigmatism. In case of horizontal astigmatism 61.2%, vertical 2.8% and rest else for 36%. Setting point from Binocular vision tells that average adding power of 40-44 (+0.75D) or (+1.00D), 45-49 (+1.25D) or (+1.50D), 50-54 (+1.50D), 55-59 (+2.00D), 60-64 (+2.50D), 65-69 (+2.50D) or (+2.75D), over $70{\leq}(+3.00D)$ or (+3.25D) of average adding power.

  • PDF

Characteristics of Accommodative Lags Determined by Objective and Subjective Methods and Their Correlation (타각적 및 자각적으로 결정된 조절래그의 특성과 상관관계)

  • Yu, Dong-Sik;Kwak, Ho-Weon;Roh, Byeong-Ho;Son, Jeong-Sik
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.20 no.3
    • /
    • pp.333-339
    • /
    • 2015
  • Purpose: The aim of this study was to evaluate clinical characteristics of subjective accommodative lags determined by fused cross-cylinder (subjective method), and an open-field autorefractor (objective method) under uncorrected and corrected conditions. Methods: Thirty three healthy subjects (26 males and 7 females aged $23.73{\pm}1.35$ years from 22 to 27 years) participated. Four methods were used to determine accommodative lag: (1) a subjective method with the fused cross-cylinder (FCC) under +2.00 D fogging lenses condition, (2) an objective method with the autorefractor under uncorrected condition (3) a corrected method (effective accommodative lag) using equations presented by Gwiazda et al. in objective methods, and (4) a corrected method using equations presented by Mutti et al. in objective methods. Results: The mean accommodative lags were 0.72 D for subjective method, 0.82 D for uncorrected objective method, 0.88 D for corrected method with Gwiazda's equations, and 0.78 D for corrected method with Mutti's equations. There were significant differences between the objective accommodative lags, but no significant differences between the objective and subjective accommodative lags. The effective accommodative lags showed significant correlations between phorias and refractive errors. The effective accommodative lag by Mutti's equations had a high correlation with uncorrected accommodative lags (r=0.99, p<0.001). Conclusions: The objective accommodative lag correlated with phorias and refractive errors. Especially, The effective accommodative lag using Mutti's equations may be considered for clinical availability and qualitative evaluation associated with symptoms.

A Study for Exact Spherical Diopter by Cross Cylinder Lens and Red·Green Card Method (크로스 실린더법과 적·녹검사를 이용한 정밀구면 굴절력에 관한 고찰)

  • Yoon, Kyounghan
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.4 no.2
    • /
    • pp.39-43
    • /
    • 1999
  • In this study, It obtained results that the exact spherical diopter to practice test by using Cross cyliner lens and Red Green Card method. In the test used to the 1750 eyes of middle and high school students. The results was as follows ; 1. Using Cross cylinder lens method, I tested a exact spherical diopter after accommodation. At -0.25 Dptr the ratio of spherical Dptr error limits were measured as 58% and at -0.75 Dptr they were oppeared as 1%, at -1.00 Dptr they are not measured. In this method, the error limits of exact spherical Dptr was 91% from 0 Dptr to -0.25 Dptr. 2. Using Red Green Card method, they were measured as 45% at -0.25 Dptr. and measured as 20% at -0.50 Dptr. From the result of these test, Cross cylinder lens method was a better detailed method than Red Green Card method.

  • PDF