In cases that come on slowly and which are accompanied by symptoms of vascular disturbance or structural changes in the eye, or brain, treatment is likely to be less successful. Nevertheless cœnurus may be removed by surgical means, depressed fractures may be elevated, and acute cerebral and meningeal congestions may be met by appropriate measures. If the cerebral congestion is acute, free bleeding from the jugular with a strong purgative and the application of ice or cold water to the head may prove useful. Apparent benefit has also followed the use of blisters on the face or back of the ear, of setons, and later of a weak electric current and strychnia. Tumors also may be advantageously removed.
But in cases marked by destruction of the retina or papilla, by congestion or atrophy of the optic nerve, by destructive disease of the optic foramen, or of the brain or its meninges, treatment is futile.
ANOPHTHALMOS. ATROPHY OF THE EYEBALL. PHTHISIS BULBI. MICROPHTHALMOS.
In some cases the eye is congenitally absent (Anophthalmos). In others it is abnormally small. One such case came under the notice of the author in which the eyeball was represented by a small black sphere about half an inch in diameter moved by the ocular muscles. The dam of the filly, born with this defect, had, during the pregnancy, a burdock entangled in the forelock and causing a violent ophthalmia which was supposed to have lasted for months. In other cases there is a fistula opening from the vitreous behind.
Cases of wasting and atrophy of the eye follow on exudates into the vitreous and their subsequent contraction, or on suppuration and granulation as noted under internal ophthalmia, recurrent ophthalmia, and panophthalmia. The condition may also result from atrophy or degeneration of the optic nerve or of its cerebral ganglia (thalamus, corpora quadrigemini, geniculata, etc.). These conditions are irremediable.
LUXATIO BULBI. DISLOCATION OF THE GLOBE OF THE EYE.
Definition. Dog, anatomical factors. Symptoms: protrusion of bulb through palpebral orifice, orbicular spasm, vessel, muscle, nerve stretching or tearing. Sphacelus. Panophthalmia. Fracture of orbit. Treatment: early reduction, antisepsis, astringents, scarify sclera, cold, astringents, puncture aqueous with hypodermic needle, enlarge palpebral opening, suture and compress, remove foreign bodies and injurious fragments of tissues, enucleation.
Definition. Displacement of the globe of the eye out of the orbit and through the eyelids.
Causes. Among domestic animals the condition is most frequently seen in the dog, which is predisposed by reason of the normal prominence of its eye, the width of the aperture between the lids and the absence of the orbital process of the frontal bone. Blows upon the region and the insertion of pointed bodies, (teeth, horns, etc.), which can act as levers using the margin of the orbit as a fulcrum are especially liable to cause the lesion. Dog fights are the most common occasions. Other animals may also suffer but not at all frequently.
Symptoms and lesions. In the simplest form the bulb is displaced forward out of the orbit and through the palpebræ which latter contract spasmodically behind it and effectually prevent a spontaneous reduction. The optic nerve, muscles, and vessels are unduly stretched and the circulation in the bulb is seriously impaired, so that even in the least complicated cases any undue delay in reducing the dislocation will lead to serious and destructive changes in the eye. Sphacelus of the globe is not uncommon under such conditions.