On insufficiency of the power of convergence / by E. Landolt.

  • Edmund Landolt
Date:
[1886]
Catalogue details

Licence: Public Domain Mark

Credit: On insufficiency of the power of convergence / by E. Landolt. Source: Wellcome Collection.

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

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    most from ocular hygiene and attention to the general health, though I would not entirely exclude, in suitable cases, all operative aid or prisms. The two following cases are characteristic examples of the neuropathic form of motor asthenopia. Case 7.—A young nun. L : myopia = 2-25 D R : do. = 275 D / V ~ I- Asthenopia of high degree. When the eyes were quiescent there was divergent strabismus of 50. p did not exceed 1 m. a. In the course of five months I successively advanced both interni, and tenotomised both externi; the immediate effect was, on each occasion, very good, and for some time there was even considerable convergent strabismus with homonymous diplopia, which, after a time, passed off, as did also, for a while, the asthenopia ; nevertheless, at this moment, p is only = 4 ) r _ _ 2 J a = 6 m. a. Both apparent divergent strabismus and asthenopia still persist to a certain extent. It would be impossible to find a better instance of remarkable reduction of the power of convergence or fusion. The insertion of the externi has visibly receded, while the interni have become attached close to the corneal margin. The oper- ations performed would have sufficed to cure the highest degree of external squint, but, notwithstanding this, the eyes can only converge to a distance of }( metre, while they have regained their former condition of divergence. The field of fixation is almost normal in the horizontal plane, though, perhaps, slightly increased internally. Still more instructive is the following:— Case 8.—A young teacher who observes and answers very accurately. There is general weakness of the muscular system. L : myopia = rjD; V= 1, R : do. = 2 D ; V = -8 Motor asthenopia which prevents him working for more than four hours daily. Fields of fixation somewhat limited in every direction. P = 4'5 I
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