An examination, under atropine, of the refractive state of eyes with normal vision (20/20), and which had never been affected with asthenopia or inflammation / by D.B. St. John Roosa.

  • Roosa, D. B. St. John (Daniel Bennett St. John), 1838-1908.
Date:
[1878?]
Catalogue details

Licence: Public Domain Mark

Credit: An examination, under atropine, of the refractive state of eyes with normal vision (20/20), and which had never been affected with asthenopia or inflammation / by D.B. St. John Roosa. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    • ' JAN .. AN EXAMINATION, UNDER.ATROPINE, OF THE RE- FRACTIVE STATE OF EYES WITH NORMAI, VISION (IJ), AND WHICH HAD NEVER BEEN AFFECTED WITH ASTHENOPIA OR INFLAMMATION. By D. B. St. John Roosa, M.D. It will be at once seen that it is a very difficult thing to procure for examination many eyes that answer to the above-named con- ditions ; and when is added to them another, that is, that the subjects shall be between twenty and forty years of age, the difficulties are not diminished. The importance of such an examination is, how- ever, I think, considerable, for it has been claimed by some that latent hypermetropia and astigmatism are the causes not only of asthenopia, conjunctivitis, blepharitis, etc., but also of chorea and lachrymal disease, while on the other hand, as good an authority as Dr. E. Hansen, of Copenhagen, is very sceptical as to the uni- versal or even general value of the correction of hypermetropia for the relief of asthenopia. In a conversation with Dr. Hansen, last summer, he informed me that he found that glasses in ve.y many instances seemed to utterly fail to afford relief to asthenopia asso- ciated with and apparently caused by hypermetropia. Dr. Hansen has peculiar opportunities for observation upon this subject, for Ire enjoys almost a monopoly in ophthalmic practice in the Danish cap- ital ; and patients have not the same liberty that is enjoyed in Amer- ican, English, or German cities, of roaming about from one oculist to another when their glasses do not suit, or their eyes do not get well. We have had abundant statistics as to the existence of myopia and as to the apparent refraction of unatropinized eyes. I have thought it desirable, however, to learn the refraction of those that have been classified as emmetropic. It is claimed, however, that there is a source of error in drawing conclusions from this kind of an examina- tion. It has been said that we almost invariably flatten the lens in putting an eye under the full influence ofatropia. If this be true, we always either diminish myopia under such circumstances, or convert emmetropia into hypermetropia. My statistics show that there was a certain proportion of cases among those examined that continued to reject even the weakest convex glasses, after atropia had been thoroughly used. Besides, I