The eyesight of school children : being a record of the examination of over 3,000 school children / by W. B. Inglis Pollock.

  • Pollock, W. B. Inglis.
Date:
1906
Catalogue details

Licence: In copyright

Credit: The eyesight of school children : being a record of the examination of over 3,000 school children / by W. B. Inglis Pollock. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

    21/36 (page 19)
    in the earlier years of school life, and from the age of eight it exhibits a progressive decrease. The true relation of these figures to the causation of myopia will be discussed later. The Degree of Myopia. Although it is generally known that those who are near-sighted tend to become more near-sighted, yet individuals who are myopic, do not often admit that their myopia has increased. It is there- fore of interest to find what light is thrown upon this aspect of the subject by my investigations. We have already discovered that the number of myopic children is constantly increasing as the children become older. The question is, do such children remain of the low degree of near-sight in which the myopia originated, or does the amount of myopia increase ? To answer this question, the myopic eyes and the mixed astigmatic eyes have been arranged in three groups according to the degree of myopia. The first includes all of less than one degree of near-sight (one dioptre); the second those between one and four degrees (one to four dioptres); and the third all over four degrees, reaching, in fact, ten degrees in one case (four to ten dioptres). Table VIII. gives the result arranged according to ages. In the case of myopic astigmatism the average was taken, and entered in the corresponding group. Illustration II. exhibits the percentages for the different ages, of each group to the total myopic eyes for the respective age. The curve of the first group exhibits a distinct and progressive decrease. Commencing at 100 per cent, by the age of eighteen it has fallen to o per cent. The second group, on the other hand, increases in a somewhat irregular fashion during the first two thirds of school life, and then maintains its position, except for the age of eighteen when it likewise falls to o per cent. The third group, consisting of eyes with a fairly high degree of myopia, presents an almost continuous rise in numbers. It does not appear until seven years of age, which means that two years or even three years of school life have been sufficient to produce this rapid develop- ment of myopia. At sixteen years of age almost 20 per cent, of the myopic eyes are included in this group while at eighteen the entire number belongs to it (100 per cent.). In other words 25 per cent, of the scholars at eighteen years of age are myopic, and each has over four degrees of near-sight. There is thus very distinct evidence that the number of eyes