網頁圖片
PDF
ePub 版

organic diseases of the brain, and disturbances of the cerebral circulation. The ordinary premonitory or associated symptoms, by means of which we may be facilitated in our diagnosis of cerebral from sympathetic conditions of morbid vision are as follow:-*

In all cases of centric cerebral amaurosis, the patient complains of vertigo and headache. The cephalalgia is sometimes acute in character, but occasionally of so mild a type as altogether to escape observation. The headache is associated occasionally with sympathetic affections of the other organs of sense, such as the hearing, smelling, &c. The mind in many cases also exhibits symptoms of disorder. The patient complains at times of great depression of spirits, is occasionally suicidal, and frequently troubled with hallucinations.

The cephalalgia of centric cerebral amaurosis is, according to the experience of all authorities, not generally of a permanent and stationary kind; it occasionally entirely disappears, but is extremely liable to recur in violent paroxysms. "The remissions," says Dr. Copland," from this severe suffering are often so remarkable as to lead a superficial observer to the belief, that it is merely periodical headache connected with dyspepsia." The character of the headache differs remarkably in various cases. Sometimes it is acute and lancinating; in other instances it is oppressive and obtuse. The pain is frequently referred to a particular spot. During the severe paroxysms, the headache is aggravated to perfect torture by the slightest motion, is greatly increased by mental

* Mr. Jabez Hogg has called professional attention to an extremely inge nious instrument, termed the " Ophthalmoscope," by means of which the more obscure diseases of the eye are easily detected, and diagnosed. This discovery will effectually aid the physician in distinguishing cerebral from those amaurotic affections, the effect of organic changes in the delicate structure of the eye itself.—(Vide Mr. Hogg "On the Use of the Ophthalmoscope in the Exploration of Internal Diseases of the Eye." London, 1859.)

† Med. Dict.

application, aggravated when the patient stoops, and becomes acute under the influence of stimulants.

Dyspeptic symptoms, often accompanying a pain and sickness of the stomach, occur occasionally during the severer paroxysms of cephalalgia. When alluding to these symptoms, Dr. Abercrombie observes, "after some continuance of fixed headache, the organs of sense become affected, as the sight, the hearing, the taste, and smell, and occasionally the intellect." The loss of sight generally takes place gradually, being first obscured, and, after some time, entirely lost.

Double vision soon supervenes. This condition may either be permanent or occur at intervals. A remarkable case is on record in which blindness took place rather suddenly, and, after it had continued some time, sight was restored by an emetic. The vision was distinct for an hour, and then, alas! was permanently lost. The intellect is frequently impaired in these cases, and sometimes the speech is lost. The morbid appearances after death present no uniformity.

"In two cases there were tumours so situated as directly to compress the optic nerve; in another, a large tumour pressed upon the corpora quadrigemina; in a third, the disease was situated at the lower part of the anterior lobe; and in another, in which the right eye was affected, it was in the substance of the left hemisphere, near the posterior part. In a case by Drelincurtius, the disease was an enlargement of the pineal gland; and in another case, in which there were both blindness and deafness, a large tumour was found, situated between the brain and the cerebellum."*

Amaurosis is occasionally the effect of local pressure on the optic nerve, or on some portion of the brain in its immediate neighbourhood. This affection arises from * "Abercrombie on Diseases of the Brain," p. 318.

organic disease of the cerebellum, as well as the cerebrum, and from lesions in parts of the brain remote from the origin of the nerves of sight. The impairment of vision is often the consequence of white softening, abscess, and atrophy of the brain and other conditions of the tissue connected with disordered states of nutrition. This disorder, however, is not necessarily the effect of congestion, or organic alterations in the optic nerve or thalamus. Andral relates the particulars of several instances of disease of the cerebellum, accompanied by a complete loss of vision. This distinguished pathologist, when referring to these cases, says, "I am unable to account for the phenomenon. In two out of twelve cases of softening of the cerebellar lobes, blindness existed on the side of the body opposite the lesion."*

The organic diseases within the cranium, which occasionally produce amaurosis, are such as result from inflammation, softening (acute and chronic) serous effusion, induration, abscesses of various kinds, tumours, tuberculous formations, adipose tumours, flesh-like tumours, tumours of a fibro-cartilaginous nature, bony and calcareous concretions, hygromatous tumours, cysts containing a serous or albuminous fluid, hydatids, fungus hæmatodes, melanosis, hæmatomatous tumours, disease of the blood-vessels, aneurismal tumours, thickening of the membranes, depositions of matter between their laminæ; dense tumours of a uniform whitish or ash colour, and exhibiting the appearance and properties of coagulated albumen, which are most frequently attached to the dura mater; diseases of the cranial bones, osteosa coma, exostosis, &c.

In an amaurotic boy, who was attacked by mania a short time before his death, Beer found a considerable

[ocr errors][merged small]

spicula at the side of the sella turcica which had penetrated the optic nerve at the chiasma.

The most frequent cause of amaurosis is a albuminous exudation, commonly the result of meningitis, taking place at the base of the brain compressing the chiasma of the optic nerve. The oculo motor nerve, from its close proximity, is generally involved in the disorder, so that convulsions or paralysis of the muscles of the eye are found to co-exist.*

"Amaurosis from organic disease within the cranium is frequently complicated with epilepsy, apoplexy, paralysis, and affections of the mental powers. It is remarkable that tumours, for example, will be found under the first class, unaccompanied by any remarkable symptoms, while under the second in the same situation, and of no larger size, they were associated with blindness, convulsions, or paralysis.

"It does not appear that these diversities depend either upon the size of the tumours, or, as far as we know at present, upon their particular structure. But these points remain to be investigated; particularly what diversity of symptoms is connected with the nature of the tumours, and especially with their characters as being tumours distinct from the cerebral mass, or as being indurations of the substance of the brain itself.†

"The loss of vision, which results from organic cerebral disease, more commonly affects one eye previously to, or independently of, the other; and if both are attacked, the amaurosis is more rapid in one than in the other, but frequently at the commencement of the disease the field of vision is not equally obscure."‡

The patient complains of musca volitantes, scotoma,

"A Manual of the Nervous Diseases of Man," by M. H. Romberg, M.D. Translated by E. H. Sieveking, M.D., vol. i. p. 232. London, 1853. +"Abercrombie on Diseases of the Brain," p. 322, 323.

Tyrrell, "Cyclopædia of Practical Surgery," vol. i. p. 94.

or sometimes there is increased sensibility to light with luminous spectra and contracted pupil. Not unfre quently objects appear distorted and confused with convulsive movements of the globe or eyelids. As the amaurosis becomes more complete, the vacant stare of the amaurotic patient is evidenced; the pupil becomes widely dilated and motionless, and the muscles convulsed. The eye usually appears on examination free from all organic change, and the retina, as far as can be ascer tained, to be perfectly sound in its structure. But the appearance of the eye, and particularly of the pupil, is not to be depended upon, for, although it is usually dilated and immovable, the exceptions are too numerous to admit of its being considered as of uniform occurrence.*

Sudden loss of sight is occasionally premonitory of apoplexy. A locksmith experienced considerable vertigo for eight days. He then suddenly became blind. He remained in this state of vision for fifteen days, when he was seized with sudden deprivation of consciousness, followed by paralysis. His sight was gradually restored, but the hemiplegia continued.+

The impairment of vision which so often precedes apoplexy, may exist for some time without being recognised by the patient or his friends in consequence of the defect of sight being limited to one eye, the other compensating, as suggested by Dr. F. Devay (of Lyons), for the weakness of its fellow.

Total loss of sight, unassociated with other symptoms of brain disease, may exist for a long period antecedently to the manifestation of other symptoms of cerebral disorder. Baron Hornestein, whose case is cited by Wepfer, became blind three weeks before he was seized with a fatal attack of apoplexy. Dr. Young lost the sight of * "Copland's Medical Dictionary,” vol. i. p. 56.

"Anatomica Apoplecticorum."

† Andral.

« 上一頁繼續 »