The lachrymation, conjunctival injection, and nasal moisture are transient symptoms which are usually absent after the first day.
In this connection it is interesting to note that Mr. Jonathan Hutchinson, as early as 1866, recognized many of the ocular symptoms of paralysis of the cervical sympathetic, and wrote a paper thereon.
HOW DOES EXCISION OF THE CERVICAL SYMPATHETIC REDUCE INTRA-OCULAR TENSION?
This is a question difficult to answer—difficult for the reason that we are not sufficiently acquainted with the physiology of the production of aqueous humor under normal surroundings. Panas and Duvigneaud have assumed rightfully that “If the nervous mechanism of intra-ocular secretion or, to speak without hypothesis, the action of the nervous system on intra-ocular tension can be known, the pathology of glaucoma will be cleared up, iridectomy will be explained, and perhaps a new and scientific basis for the treatment of glaucoma will be established.” Many observers have sought to solve the problem. Donders attributed the hypertension to a neuro-secretory cause and believed the trigeminus to be the agent of excessive secretion. He held that section of the trigeminus should relieve intra-ocular tension, while section of the cervical sympathetic could have no particular influence.
His views were overthrown by experiments made by Wegner in 1866, on rabbits. By means of manometers placed in the anterior chamber, he sought to record variations in the intraocular tension. He proved to his own satisfaction that the trigeminus takes no part, while section of the cervical sympathetic produces hypotonia, and irritation of its upper end and causes hypertonia. He held that section of the cervical sympathetic enlarges the blood vessels of the eye; the blood then flows under reduced pressure, and intra-ocular secretion is lessened. Almost identical results were obtained by Adamück—1866–68—who experimented on cats.
Von Hippel and Gruenhagen believed that the cervical sympathetic contains vasoconstrictor fibers for the eye. Their experiments were made on cats and dogs. They found that irritation of the upper end of the cervical sympathetic causes in the cat hypertonia, while its extirpation increases intra-ocular tension. While, according to Wegner, the hypertonic action proceeds from the enlargement of vessels caused by cutting the cervical sympathetic, and the contraction of the blood vessels caused by the irritation of the nerve causes a hypertonic action, the contrary view is held by Adamück, Von Hippel, and Gruenhagen.
However this may be, there is no doubt that the trigeminus plays no great part in the production of ocular tension. Furthermore, the inefficiency of Bedal’s operation—stretching the nasal nerve—is explained by the fact that it is the cervical sympathetic, and not the trigeminus, which influences intra-ocular tension.
Jonnesco believes that the ocular sympathetic fibers from the brain and spinal cord pass through the superior cervical ganglion; permanent or intermittent irritation of these is accompanied by dilatation of the pupil, narrowing of the small intra-ocular arteries, contraction of the peribulbar muscular fibers, and probably an increased action of the elements which produce the aqueous humor. “As a matter of fact,” says Jonnesco, “any increase of the blood pressure will produce a permanent or intermittent narrowing of the arteries and cause the extravasation and increase in aqueous humor; then it is probable, although not definitely settled, that a permanent or intermittent irritation of the excito-secretory fibers is followed by an increase in the secretion of aqueous humor; the permanent or intermittent dilatation of the pupil pushes the iris into the iris-angle, closes the canals of the filtration zone, and hinders or prolongs the exit of aqueous humor from the eye; the permanent or intermittent contraction of the unstriped peribulbar muscular fibers closes the efferent veins of the eyeball, and hinders the venous circulation of the eye—hence the dilatation of the intra-ocular veins.”
He holds that excision of the superior cervical ganglion destroys all vasoconstrictor fibers of the eye. The arteries relax, the blood pressure is lowered, and extravasation is reduced. This operation destroys the excito-secretory fibers, thus limiting the amount of aqueous produced. The fibers which dilate the iris are destroyed, hence the contraction of the pupil reopens the iris-angle and removes the obstacle to the outflow of aqueous. The nerve-fibers supplying the unstriped muscular apparatus contained in Tenon’s capsule are destroyed, hence the pressure on the efferent veins is removed and ocular circulation is reestablished.
Jonnesco believes that the starting-point of the nervous derangement producing glaucoma is central: “When one removes the ganglion the point of origin of the influence will not be removed, but the communication between this center and the eyeball is destroyed.”