Among 4465 patients visited in the department of ophthalmology of the our hospital from January 1, 1975 to September 30, 1976, 146 patients (under the age of 25 ; 88 patients, over the age of 26 ; 58 patients) was statistically observed for errors of their glasses.
1) The rate of glasses over or under corrected 0. 75D or more was 37%, and of this rate, 12 % were over corrected. In age group, it was about twice the age of 25 than over the age of 26. -
2) The rate of glasses which diopters of cylindrical lens were wrongly corrected 0.50D. .or more was 65% (of 156 glasses), and of this rate, 40% were glasses which .astigmatism was absent but in refraction astigmatism was present more than 0.50D. In age group, it was about 2. 5 times the rate of it in under the age of 25 than over the age of 26. The rate of glasses which axis of astigmatism was wrongly corrected 10? orMore was 65% (of 52 glasses).
3) The rate of glasses which distance between optical centers was short or long more than 3mm was 53 %, and of this rate, the rate of long ditstance between optical centers was 3 times than that of short distance. It was also about twice the rate of in under the age of 25 than over the age of 26.
4) The rate of glasses which corrected 1/2? or mere was 20%, and of this rate glasses which vertical deviation was present but in examination vertical deviation was not present.
5) Among 146 patient, patients which has worn glasses not to belong to above the categories were only 15 patients, and rate of it was only 10%.
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