Eetropion, of the lower lid especially, may also be originated, due to the con traction of the orbicularis and exerted upon the lids—already prone to ever sion by the swelling of the conjunctiva.
Xerosis of the conjunctiva occurs as a result of the cicatrices. The blood-sup ply to the conjunctiva is shut ofr and its epithelium undergoes fatty degenera tion. The surface of the membrane then becomes dry and smooth and almost leathery, and the corneal epithelium also becomes thick-er and its transparency much interfered with. The eye finally becomes blind and a source of continued annoyance, by reason of the constant sensation of local dryness experienced.
The pannus may clear up entirely, leaving a normal cornea beneath. If there be ulceration, however, opacities remain, which disturb vision according to the extent to which they involve the pupillary area of the cornea. Fre quently, as a result of pannus, there occurs a connective-tissue metamorpho sis, which greatly interferes with the transparency of the cornea. Another re sult of pannus sometimes is a bulging, or staphylomatous, condition of the cor nea, the tissues of which have become so altered that they give way before the normal intra-ocular tension.
Etiology. — In general, the disease may be said to arise from poor hygienic conditions. It develops in institutions where the inmates are crowded together, in armies, orphan-asyltuns, almshouses, and the like. It is probable that the so called lymphatic or scrofulous tempera ment predispose toward it, although the disease may attack those in perfect health.
'Trachoma always arises through in fection from another eye already in fected, by means of the secretion; only under exceptional circumstances, when the air is heavily 'charged with the poison, can it be the medium of com munication of the disease. The fectious nature of the secretion is doubt less due to micro-organisms; but, while numerous bacteria are found in the secre tion, gonococci, streptococci, etc., the specific germ has not yet been isolated.
Etiological factor in acute contagious eonjunctivitis a small, unknown bacillus. Weeks (N. Y. Eye and Ear Infirmary Reports, Jan., '95).
It is always contagious,—frequently epidemic. The symptoms, which vary in severity, begin two or three days after infection, with gluing together of the eyelids on awakening in the morning, and small, yellowish masses at the base of the lashes. There is increased lacryma
tion, congestion, and turbid discharge. It usually begins first in one eye, but afTects both in its course. There are burning pains and the sense of a foreign body; the lids are swelled and discol ored; and the eyeball is of a rosy tint, which has given the affection the name of "pink-eye." The symptoms continue to increase for two or three days, and frequently a slight coryza arises. Victor Morax. and G. IV. Beach (Archives of Ophth., vol. xxv, No. 1, '97).
Nine thousand one hundred and sixty six cases of trachoma (1500 of which were complicated with corneal alTections) ex amined to discover whether there is any accountable pathogenic microbe or not. It was concluded that there is none, but that the morbid entity of trachoma has an histology which is characteristic and absolutely different from that of follicu lar conjunctivitis. Lessening the :.a.lka linity of the lacrymal secretion tends to the acquisition of conjunctival diseases. V. L. 11fatkovic (Rec. d'Oplitak, Feb., '9S).
Trachoma is due to encapsulated diplo coccus, Piz to 2 millimetres in length and 5 millimetres in breadth, which is not decolorized by the Gram method of staining, and whose septum at times has an affinity for aniline stains, causing the diplococcus to simulate bacillus. This organism is constantly present in the trachoma-follicle and secretions, before astringent and antiseptic remedies have been employed. E. F. Syndecker (Jour. Med. and Surg., Apr., '99).
A thorough inspection of 36 public schools in New York in July of last year showed that, of 57,450 children ex amined, 6690 AA-ere found to have some form of contagious eye disease. Of these, 2328 were severe trachoma, 3243 were mild trachoma, and 1099 acute purulent conjunctivitis. A large num ber of cases were excluded from the schools, and there was a coincident in crease in the number of trachoma cases treated in the New York eye hospitals. The question of the contagiousness of trachoma is still unsettled. It is prob able that children suffering from eye diseases of this class should be excluded from the schools until the condition has been cured. Lambert (Med. Record, Feb. 21, 1903).