A manual of medicine.

  • Allchin, William Henry, 1846-1912.
Date:
1901
Catalogue details

Licence: In copyright

Credit: A manual of medicine. 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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    such as affections of oculo-motor muscles, weakness of limbs, loss of the knee-jerk. The reaction to light is present unless the efferent limb of the light reflex is interfered with through the affection of the third nerve. It has already been mentioned that inequality of pupils may be present with perfectly normal reaction, and probably in quite healthy persons. Inequality may also be present, as has been stated, with Argyll- Robertson pupil. Sometimes inequality of pupil depends upon inter- ference with the sympathetic in the neck. Irritation on one side may cause a dilatation on that side, and this is usually associated with an increase in the size of the palpebral aperture. The pupil, however, on the affected side may be smaller, and a slight degree of ptosis may be present, and this would indicate sympathetic paralysis on this side. Inequality of pupil and interference with ordinary reactions may also be the result of anterior or posterior synechias—evidences of old iritis. It should also be remembered that operations on the iris, such as iridectomy, may give rise to irregularities in the pupil. The same also is true of a developmental defect, such as coloboma, in this structure. Morbid Changes in the Fundus Oculi Certain morbid affections of the ocular structures which show them- selves in altered appearances visible in the fundus of the eye are of great importance in themselves and also as the indications of diseased affections elsewhere, usually of the nervous system, although other structures of the body may be those mainly concerned in the morbid process. The optic disc is probably the most significant part of the fundus, and changes indicative of disease may be visible in that struc- ture while the rest of the fundus remains undisturbed. The changes which take place in the disc are—- (1) Those indicative of hyper^emia. (2) Those indicative of inflammation—optic neuritis or papillitis. (3) Those indicative of atrophy of the nerve—optic atrophy. But other morbid conditions may be present, in which little or no change may appear in the disc, e.g. so-called retro-bulbar neuritis, in which the inflammation is behind the globe and only manifests itself later when the fibres involved have atrophied and so given rise to some change in the appearance of the disc. On the other hand, changes in the disc may succeed some morbid vascular process such as embolism, and may also be consecutive to some diseased condition of the retina and choroid. And there may be retinal changes such as haemorrhages unassociated with visible morbid appearances in the optic nerve, and depending upon some blood state, such as anaemia, leucocythsemia, uraemia, etc.