The cure of strabismus by surgical operation : being an appendix to the first, second, and third editions of his 'Practical treatise on the diseases of the eye' / by William Mackenzie.

  • Mackenzie William, 1791-1868.
Date:
1841
Catalogue details

Licence: Public Domain Mark

Credit: The cure of strabismus by surgical operation : being an appendix to the first, second, and third editions of his 'Practical treatise on the diseases of the eye' / by William Mackenzie. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    prevent the distortion when on their guard. A recent and transient strabismus is not unfrequently the result of intense use of the eyes, men- tal agitation, or irritation communicated from the abdominal viscera to the brain. Such cases should be treated with rest, purgatives, tonics, and proper exercise of the eyes. It is only when strabismus has continued for a considerable length of time, generally for years, and has attained the character of being conjirmed, that we should think of remedying it by operation. * In a valuable analysis of 200 cases of strabismus, Mr Radclyfte Hall® enumerates the following causes as those assigned by the patients them- selves or their parents, without vouching for the correctness of the testi- mony, except where physical conditions yet remained to substantiate the opinions given. “ 1. Convulsions during infancy, in 9 cases ; falls on the head, in 7; severe con- cussion of the brain, in 1; difficult dentition, in 3 ; hooping-cough, in 3 ; intestinal worms, in 3 ; epilepsy, in 2 ; a severe thrashing, in 1; excessive fright, in 1. “ 2. Ophthalmia which had left no opacities, in M ; opacity of the cornea, in 5 ; opacity said to have existed formerly, in 1 ; wound of the cornea, by a stocking needle, in 3 ; by a fork, in 1; by a thorn, in 2 ; blow on the eye. in 5 ; burn of the eye from a piece of metal flying into it, in 1 ; a habit of looking at the sun, in 3 ; crush from a cart-wheel going over the orbit, in 2 ; amaurosis, in 2 ; imperfect eatar.act, in 3 ; exposure during infancy to the light and heat of a blazing fire, in 3. “ 3. Imitation of asrjuinting person, in 39 ; watching the motion of a shuttle, in 1 ; voluntarily trying to squint, in 1 ; a habit of looking at a sear on the eye-brow, in 1 ; at a scar on the nose, in 2 ; at a scar on the cheek, in 2 ; at a small encysted tumor at the inner *canthus, in 1; at a small naevus in the same situation, in 1 ; at a mole on the nose, in 1; a habit of sucking the thumb, and looking stedfastly at it, at the same time, in 1; Iwlding the head sideways whilst knitting, in 3., “ 4. Measles, in 4 ; small-pox, in 0. “ 5. Severe buims of the abdomen, in 2.” lu four instances, Mr Hall was assured that the strabismus was con- genital. In the remaining cases of the two hundred, no causes were as- signed. Mr Hall’s remarks on the different classes of causes are highly judi- cious. It appears probable, that in the 1st and 5th classes, an unequal com- munication of nervous energy to the muscles of the eye, in consequence of disease in the brain or its vessels, is the origin of the distortion. In the 2d and 4th classes, the distortion is probably at first an effort to free the eye from pain, or the result of such disuse of the eye and of its natural movements, as must often arise from wearing a shade over one eye. In the 3d class, strabismus arises from habit. In the early stage of every strabismus, double vision must exist. An effort to free the vision from the confusion, attending diplopia, probably increases the distortion. As the disease becomes confirmed, the vertex of the retina of the squinting eye, being no longer turived towards objects, and therefore receiving only the light which falls upon it obliquely, seems to lose a great share of its sensibility, merely from disuse. In all the five classes, strabismus, having once become habitual, so that one of the muscles of the eye is almost always in a state of active con- traction, while its antagonist is left in a state of relaxation, the former not only obtains an increase of power at the expense of the latter, but there is reason to think that interstitial changes sometimes take place, by which the active muscle may become hypertrophied, and the inactive one wasted. The process by which such a condition of the parts can be