Eyestrain (commonly called asthenopia) / by Ernest Clarke.

  • Clarke, Ernest, 1857-1932.
Date:
1892
Catalogue details

Licence: Public Domain Mark

Credit: Eyestrain (commonly called asthenopia) / by Ernest Clarke. Source: Wellcome Collection.

Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.

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    I take to belong to the same category. In all there is a faulty blood metabolism, and consequent neuro-muscular debility, and it would seem that unstriped muscle sufifers seriously from such defective haemopoiesis, the heart and arterial muscles exhibit lack of tone, the pulse is soft, often irregular, and palpitation is common, the muscular fibre of the intestines suffers, and chronic constipation is a frequent concomitant; the ciliary muscle, with or without associated affection of the iris, is similarly weakened, and the amplitude of accommodation is seriously restricted.^ The prognosis of neurasthenic asthenopia is neither good nor bad. The visual symptoms rarely develop into actual disease, but although they may be relieved or cured for a time, the general nervous excitability scarcely ever quite disappears, and so relapses are common ; although I have seen several cases I have never yet seen a complete cure. IV. Anaemia is another disease that is a common cause of ciliary strain. Here again we have faulty blood metabolism ; and the lack of sufficient oxygen-giving blood naturally induces diminished vital power. Anaemia shows itself in young girls, very often at the age of 14 or 15, and this is just the period when more work is forced upon the ciliary muscles. It is the time in their school life when hard work either begins or reaches its maximum, they are begin- ning to prepare for those severe tests—examinations. Thus, instead of diminished ciliary power they want more. The headaches so often accompanying anaemia are often induced and if not induced, exaggerated by eyestrain. Giraud Teulon found among 727 cases of ciliary strain in school children with Hyperopia, 532 i.e., 63 per cent, suffer- ing from anaemia and adynsemia.^ ' R.L.O.H. Reports, vol. xii., p. 328. 2 Knapps Archiv., vol. xv., p. 223,