The refraction of the eye; including a complete treatise on opthalmometry; a clinical text-book for students and practitioners . simple hypermetropic astigmatism intoa simple hypermetropia of 1 D. (see Fig. 76). The patient by means of his accommodative power cancorrect this simple hypermetropia (as produced by the minuscylinder) with comfort at times, because he can use the wholeof the ciliary muscle regularly ; while he could not correct thesimple hypermetropic astigmatism without discomfort, since,in that case, it must contract irregularly to act on the horizon-tal meridian of the lens with
The refraction of the eye; including a complete treatise on opthalmometry; a clinical text-book for students and practitioners . simple hypermetropic astigmatism intoa simple hypermetropia of 1 D. (see Fig. 76). The patient by means of his accommodative power cancorrect this simple hypermetropia (as produced by the minuscylinder) with comfort at times, because he can use the wholeof the ciliary muscle regularly ; while he could not correct thesimple hypermetropic astigmatism without discomfort, since,in that case, it must contract irregularly to act on the horizon-tal meridian of the lens without at the same time acting on the MIXKD ASTIGMATISM 17. vertical meridian, which is emmetropic and should Be let alone. Such is tin- simple explanation of these cases. No strongerplea could !>•? urged ir tin- beginning of all tests with plus a -. I .mi sure. recapitulate: mosl cases of mixed astigmatism ran !><•correctly fitted with glasses without the use of a mydriatic,provided that first, the amount and axis of the corneal astig-matism he ascertained ; next, that the test for glasses be begun. Fig. 76.— (.4) Before correction. (B) After correction with —ID eyl., 180°, bywhich the simple hypermetropic astigmatism is converted into a simple liyper-metropia of 1 D. with weak plus glasses and their strength gradually increased ;and finally minus glasses tried. The chief indication for a mydriatic in such cases, as in allother of refractive error, is a spasm of means of detecting spasm of accommodation have alreadybeen pointed out elsewhere, so we need not consider themagain. Case LXXf Mixed astigmatism of large amount and with//,. /-,//. in each eye; Asthenopia; Relief with glasses. — April 21, 180 THE REFRACTION OF THE EYE 1893, Miss S. A., aged twenty-two years, in good generalhealth, has had trouble with her eyes for the last six now complains of having to hold the print too close to hereyes when she reads, also of
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