[Transactions of the American Ophthalmological Society] ; Transactions of the American Otological Society : second annual meeting, Newport, R.I., July, 1869.

American Ophthalmological Society

Date:: [1869]

Credit: [Transactions of the American Ophthalmological Society] ; Transactions of the American Otological Society : second annual meeting, Newport, R.I., July, 1869. 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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$diiction at 12 inches now ainoiiiited to 2^, tlic adduction to 18°. The left internus was now divided, and tlie results of the exam- ination made three weeks after the last operation were as fol- lows. If the colored gdass was used alone over one eye there was no homonymous diplopia, even for 20 feet, nor did this occur anywhere from the distance up to the near point, even when the candle was moved laterally across the field of vision; luit if the prism, base up, was added, a small degree of insutliciency (one or two degrees) of the externi was still ap- parent. The patient is entirely relieved of his asthenoi)ia and diplopia, and can use his eyes to the full amount without ex- periencing any inconvenience. Ip the above case there are two ])rincipal jioints to which I would particularly call your attention. (1.) That although there was no actual strabismus, both interni had to be divided to restore the muscular eciuilibrium. (2.) That although the patient could, witli an ellbrt, carry out his optic axes to the parallel, the relative accommodation was so displaced inward, when the eye was adjusted for near objects, that distinct vision was not ])Ossible outside of 12 inches, while near vrork was usually })erformed at 7 inches. To show that this dis})lacement of the relative accommoda- tion may take ])lacc when the insufficiency of the externi is the result of ojierative interference, 1 would call your atten- tion to the very interesting case presented at one of the late meetings by a member of the X. Y. Ophthalmological .Society. The ])atient was a young lad of about 12 years of age. In this case there was a total hypermetropia of 1-8, with vision = 1. There wa§ an insufficiency of the interni amounting to 8° for the far and 14° for the near. In order to relieve this both externi were divided at the same sitting. The result of this double tenotomy was homonymous dijilopia of so great a degree that single vision was only obtained Avhen the object was brought within 6 inches of the eye. This diplopia grad- ually became less, till at the end of three weeks it only oc- casionally manifested itself. ‘The patient’s total hypermetropia was neutralized, -f 1-8 being given. AVith these glasses vision was 1, and there was no diplopia. The error in refraction having been completely neutralized, the eye might be con-$