A system of practical medicine. By American authors. Vol. 4

by Unknown

Mental Affections.

It is admitted by all observers that affections of the pupillary branch of the third pair, such as mydriasis, myosis, and inequality of the pupils, are of comparatively frequent occurrence among all classes of the insane. There is the widest difference of opinion as to the percentage of cases in which it occurs: thus, Nasse out of 229 cases found 146 (64 per cent.) with difference in the size of the pupils, while Wernicke found 24 per cent. in the Leubus Asylum, and only 13 per cent. in the Breslau Institute. The latter author has attempted to classify the pupillary lesions into three groups:

I. Mydriasis, with loss of accommodation, where the pupil does not react to light nor with increased convergence of the eyes.

II. Where the pupillary difference is slight and the irides less prompt than normal in reaction to light, all difference of the pupils disappearing upon convergence of the eyes.

III. In which the irregularity is still less, the narrower pupil being absolutely insensitive to light, but prompt in responding to convergence, while the more dilated pupil acts promptly in obedience to both light and convergence.

In the first group there is some lesion in the course of the third pair; in the second, some lesion of the sympathetic either in the cilio-spinal centre or in its unknown intracranial distribution; whilst in the third, which is not so readily explained, there is possibly an affection of those fibres which pass from the third pair to the optic nerve. Foerster²⁶⁸ states that he has frequently seen cases where at different times the same pupil under similar circumstances showed different diameters; also asserting that variation in the relative sizes of the two pupils sometimes occurred within a few days or weeks. He also maintains that in many cases the occurrence of inequality in the pupils precedes and presages the occurrence of insanity; and as a marked example of it he quotes the case of a friend and colleague who observed this phenomenon in himself. This person was well aware of the theories on the subject, and while yet of sound mind jokingly remarked that on account of this inequality of pupils having set in, he thought of taking up his quarters in an insane hospital. A few years later he actually died insane in the Leubus Asylum. Myosis is said to be frequent in states of mental exaltation. Seifert asserts that when it is accompanied by acute mania general paralysis will sooner or later ensue. Griesinger asserts that the same thing occurs in chronic mania. As regards the changes in the optic discs in the insane, we find usually recorded either a low grade of neuritis or of atrophy: according to Leber²⁶⁹ this atrophy is histologically similar to that occurring in gray degeneration of the nerves. The outer strands are usually those most affected. Indeed, as far as these obscure diseases are at present understood, there is no good reason why any changes should be found in the optic nerves except the congestion which accompanies acute or subacute mental disease and the nerve-degeneration of various grades which might be expected to be found in all worn-out lunatics. Illusions and hallucinations referable to the sense of sight are not uncommon in the insane, and are perhaps due to degenerative changes in the visual centres. In classifying such cases for study of the intraocular changes most writers place them under the following heads—viz.: general paralysis, dementia, mania, and melancholia,²⁷⁰ the account of the changes in the eye-ground and the proportion of cases in which they occur being found to vary greatly.

²⁶⁸ G. u. S., vol. vii. p. 227.

²⁶⁹ A. f. O., xiv., 2, p. 203.

²⁷⁰ Noyes, "Ophthalmoscopic Examination of Sixty Insane Patients in the State Asylum at Utica," pp. 6 (extra copy from Amer. Journ. of Insanity, Jan., 1872).

GENERAL PARALYSIS.—Almost all agree that in this form of the disease we frequently have gray degeneration of the optic nerve, with pupillary symptoms which strongly resemble those found in tabes dorsalis, in some instances the autopsy showing the same location of spinal changes which characterizes the changes seen in locomotor ataxia.