On the influence of the cervical portions of the sympathetic nerve and spinal cord upon the eye and its appendages, illustrated by clinical cases, with observations / by John W. Ogle.

  • Ogle, John W. (John William), 1824-1905.
Date:
1858
Catalogue details

Licence: Public Domain Mark

Credit: On the influence of the cervical portions of the sympathetic nerve and spinal cord upon the eye and its appendages, illustrated by clinical cases, with observations / by John W. Ogle. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    nerves and spinal cord by branches of junction between them. Thus the iris enjoys a double innervation ; the one cerebral, the other spinal; each antagonising and balancing the other. This counterpoise of the opposing fibres of the iris is well illustrated by the dilatation of the pupil which, as a general rule, occurs along with ptosis and abducent squint, when the third cranial nerve is divided experimentally, or much pressed upon by an int^^- cranial tumour, &c., the iris- dilating or extensor fibres being then unopposed by the / sphincter or flexor fibres. It is also well exemplified by the following circumstances. When a longitudinal opening is made into the iris of a rabbit, the artificial pupil becomes short^ and round^ so long as the eye is healthy and the opposing flexors and extensors of the iris are not prevented from duly balancing each other; but if in the same animal the nervi molles be divided, or, as Valentin terras it, the fons spinalis be destroyed, then the artificial orifice, formerly round in form, becomes no longer so, but greatly elongated and arched, assuming a direction moi'e or less parallel with the margin of the natural pupil. Such being the state of our knowledge in regard to this matter, Budge and Waller, confirmed by experiments,^ in 1841, the fact that those branches of the sympathetic which control certain motions of the iris have not their real origin from the main trunk or the ganglia of the cord in the neck, but that they arise from the spinal cord, passing through the spinal nerves to the cervical sympathetic; and in those con- clusions Wagner and Ruiter^ agreed. By following the nerves step by step until they found a place where irritation produced no efiect, and by gradually removing portions of the cervical cord and watching the results on the pupils, they went on to prove, as it appeared to them, that in certain animals those branches whicli con- trol these movements of the iris were connected solely with that portion of the spinal marrow itself as a centre which 1 Vierordt's ' Archiv fur Physiol. Heilkunde,' 1852; Erganz. Heft. ' 'De actione Belladonna in Iridem/ Dissert. Traj. ad Rhenum, 1849,