Relationship Between Visual Acuity and Refractive Error in Myopia

The purpose of this study is to present quantitative data showing the relationship between visual acuity and refractive error in the various types of myopia: simple myopia, simple myopic astigmatism and compound myopic astigmatism. 1. The study covered 681 patient (1259 eyes) examined by having refractive error in myopia. (-0.25 ~ -20.00D) the Department of Ophthalmology, Yonsei University Medical Center and Wonju Christian Hospital. 2. Plotting the logarithm of visual acuity on the logarithm of the degree of myopia gives a coefficient correlation of -0.8028. The statistical data showed significant in correlation coefficient (r) in various types of myopIa: simple myopia r=-0.7789(p=0.001), simple myopic astigmatism r=-0.7877(p=0.001), compound myopic astigmatism r=-0.7537(p=0.001). 3. The coefficient of determination (R2) was 0.6445. 4. The mathematical mean of the various types of myopia: a. myopIa; simple myopia: 0.29(=20/60), simple myopic astigmatism: 0.87(=20/25), compound myopic astigmatism: 0.29(=20/60). b. visual acuity; simple myopia: -2.53D, simple myopic astigmatism: -0.50D, compound myopic astigmatism: -3.04D. 5. The formulas for the two regression line were: log V=-0.7385 log M-0.4976 (A)(F=2175.7303, p=0.001), log M= -0.8727 log V -0.3641 (B)(F=2175.7303, p=0.001). 6. Confidence limits were determined for the regression lines and table and set up for predicting either the degree of myopia or the visual acuity if the other is known.

Refraction in School Children

518 children (282 boys and 236 girs) of a primary school were determined under mydrin-p instillation. (1) Among 518 children, Ammetropia was 43.6% emmetropia 56.4%. (2) As to the distribution of refractive error 38.2% were hyperopia and 4.1% myopic. (3) There was an anuual decrease in the incidence of hyperopia both in the country and city. In contrast, the incidence of myopia showed an annual increase in city only. (4) The majority of refractive error were less than 3 diopter. (5) "With the rule" astigmatism was more commonly found than "against the rule". (6) The incidence of myopia among primary school children in the country had dropped to 4.1 % as compared with 13.7% in city.

The Exophthalmometry, extraorbital width and height of lid fissure of Koreans

The author analysed statisticalIy the normal positional variation of the eye-ball, height of lid-fissure and the distance between bilateral orbital rim, of 500 individuals who visited to eye department. (1) In exophthalmometry, the average value was 14.69mm in male and 14.17mm in femal. (2) The distance between bilateral orbital rim was longer in male than in female. The average value was 97.29mm in male, 96.36mm in female. (3) In the height of lid-fissure, The average value was 8.06mm in male, 8.03mm in female.

A Case of Malignant Melanoma in the Conjunctiva

A case of malignant melanoma occurres in the palpebral conjunctiva is presented. A 30 year old woman had dark brownish, strawberry-like pedunclated mass in her lower conjunctiva which was removed and confirmed as malignant melanoma by histopathology.

A Statistical Observation of the Ocular Injuries (I)

The authors analysed statistically 314 cases of the ocular injuries among 37.826 Out and In-patients who visited to Severance Hospital for 6 years duration (from sept. 1965 to Aug. 1971). Male (72%) was three times as much as female (28%) among the patients and they were mostly 2nd and 3rd decades. Most frequent causes of injuries were finger. fist and iron pieces which mainly resulted in subconjunctival hemorrhage and corneal foreign body.

A Statistical Observation of the Ocular Injuries (II)

The authors analysed statistically 4,231 Cases of the ocular injuries among 19,204 Out-and Inpatients who visited to the local eye clinic at Young-Deong Po, where are many factories, from Jan. 1971 to Dec. 1971. The incidence of ocular injuries was increased about two times as much as that in 1964 at this eye clinic and was more prevalent than other places. It was shown that the incidence was exceedingly more prevalent in male than in female and iron piece was most freguent one among materials which caused trauma(64.7%). Most of the patients were improved well with proper early management of trauma. 6.6% resulted in blindness.