An inquiry into the action and uses of atropia / by Alex. Fleming.

  • Fleming, Alex.
Date:
[1863]
Catalogue details

Licence: Public Domain Mark

Credit: An inquiry into the action and uses of atropia / by Alex. Fleming. Source: Wellcome Collection.

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    tive poisoning. Again, those conditions which check the arterial flow to the eye tend to dilate the pupil, such as aneurism in the chest and neck impeding the passage of blood into and through the carotid, a tumour pressing on, or a plug in the vessel. Worms and disease of the belly in children dilate the pupil and impair the sight, probably by reflex action through the sympathetic nerve—exciting the radial fibres of the iris and contracting the cerebral arteries. Hence, also, in all likelihood, the train of anaemic head-symptoms so characteristic of tape-worm. On the other hand, those conditions which favour arterial ple¬ thora or venous congestion of the head tend to contract the pupil —such as dilatation and loss of contractility of the aorta and carotid—giving passage to a larger stream, and checking its force less, than the normal vessel. Aneurism of the innominata closing the subclavian and leaving the carotid free will increase the force of the blood current in the latter, and this will be further augmented if the carotid be diseased, dilated, inelastic, and non- contractile. It does not fall within the scope of this paper to allude to the beautiful researches of Budge, Waller, Brown-Sequard, Yon Graefe, Bernard, Harley, Bell, Hughes, and others, into the physiol¬ ogy of the iris, and of the nerves which preside over its movements, nor to the very useful application of this knowledge to practical medicine by Macdonnell, Gairdner, and Ogle, who have traced con¬ traction and dilatation of the pupil to pressure on, or disease involving the cervical sympathetic, and other parts of the nervous system connected with the movements of the iris. But, in examin¬ ing cases of aneurism, and of tumour in the neck and thorax, accompanied by alterations of the pupil, it is well also to bear in mind the causes of change in the size of the pupil to which I have adverted, and to make careful inquiry into the condition of the arterial and venous currents in the neck. The results related in this paper were obtained chiefly by observations on the eyes of my students in the Queen’s University, who most cheerfully gave me every assistance in my inquiries. I have also made numerous experiments on the eye of the cat and rabbit, some of which will be recorded in the appendix to this memoir. PRINTED BY OLIVER AND BOYD, TWEEDDALE COURT, EDINBURGH.