Chorioiditis

CHORIOIDITIS (chorioiditis), a disease of the vascular coat of the eye, the choroid. It arises in connection with inflammation of the entire uveal tract or its individual parts (see Iritis, Iris, Ciliary Body, Vascular Coat, Uveitis). Often X. is a limited disease affecting only the vascular coat. Etiology of chorioiditis. Frequently, chorioiditis is a symptom of a general disease, which necessitates thorough general examination of the entire body when present (tuberculin reaction, RW). Sometimes examination of the eye gives certain indications of the etiology of X. For example, deeply lying fine vessels in the cornea or delicate central opacities of it, deposition of pigment in the area of the pupil are remnants of syphilitic eye lesions. Analysis of the ophthalmoscopic picture also facilitates determination of the etiological factor. Thus, sclerosed vessels of the choroid are found in syphilis, arteriosclerosis, nephritis, whereas in tbc changes in the vessels are absent. Among the etiological factors of X., first place is taken by tbc, to which 70% of all cases of disseminated X. are attributed; 8% of all cases of the latter fall on syphilis, acquired and congenital. In the remaining cases, the cause of X. is either unclear or other diseases are responsible for its occurrence: gonorrhea, rheumatism, anemia, pneumonia, leprosy, influenza, postpartum sepsis, etc. In acute infectious diseases, the causative agents of inflammation (pneumococci, meningococci) reach the choroid by the metastatic route, causing X. Characteristic atrophic foci of X. are observed in high myopia in the form of the so-called central or disseminated X. In fresh cases of X., pathological changes are limited to infiltration of the choroid with mononuclear lymphocytes. Then an exudate appears between the choroid and retina, which leads to the death of the pigment epithelium, disappearance of chromatophores, and emptying of capillaries. At the site of the inflammatory focus, atrophy of the choroid develops and connective tissue forms. The latter turns into dense scar tissue, and often adhesion of the choroid and retina occurs. Sometimes proliferation of the pigment epithelium can be observed above the inflammatory focus, which more often occurs at the periphery of the focus. Naturally, the disappearance of capillaries of the choroid is accompanied by atrophy of the retina. In the late stage, sclerosis of the large vessels of the choroid occurs. In most cases, the course of X. is prolonged, and the transition of exudative foci into atrophic spots requires many weeks, and sometimes years. X. has a tendency to recur, as a result of which in the choroid one can observe alternation of old (white) and fresh (black) spots. Often X. gives complications from the lens and vitreous body (opacities), optic nerve and retina (atrophy). Severe cases of X. end in partial or complete blindness. Among the symptoms of X., various visual disturbances should be noted. Thus, decrease in visual acuity is caused by opacification of the vitreous body and edema of the retina, which is confirmed by ophthalmoscopic examination. Swelling of the choroid, its infiltration and subsequent scarring are accompanied by displacement of elements of the visual epithelium, as a result of which decrease in the size of visible objects (micropsia) and distortion of them (metamorphopsia) occur. Death of the visual epithelium will correspond to visual field defects-scotomas. The location of the inflammatory focus has a great influence on visual acuity. Scattered atrophic foci throughout the fundus may not affect vision, whereas delicate, barely noticeable changes in the area of the macula already sharply reduce visual acuity.--In the initial stage, diagnosis of X. is difficult, especially when the inflammatory focus in the choroid has the form of an barely noticeable light spot with indistinct borders. The ophthalmoscopic picture of X. in the late period is very characteristic: often the entire fundus is dotted with spots, white and black, in varying numbers and diverse shapes [see separate plate (for article Cirrhosis of the liver), fig. 3 and 4]. White spots are surrounded by black pigment, partially covered by it. The spots sometimes group around the macula (chorioiditis areolaris). In many cases they are scattered throughout the entire fundus (chorioiditis disseminata). Sometimes almost the entire fundus appears normal, whereas in the macula deposits of black pigment clumps are noticeable, or in the macula there is a yellowish-white focus bordered by pigment (chorioiditis centralis, maculitis). Finally, inflammatory foci may be located at the periphery of the fundus, where they take the form of small black roundish spots, alternating with areas of depigmentation. This variety of X. is called chorioiditis anterior and can be confirmed by the ophthalmoscope only when the head is strongly bent back and the eye is turned up and down. The types of choroid inflammation just described constitute a group of serous, non-suppurative X., whereas infection of the choroid with pyogenic microbes is the cause of purulent chorioiditis. This infection of the choroid occurs exogenously--trauma, purulent keratitis, operation on the eyeball and endogenously--pyemia, postpartum sepsis, etc. (see Eye, pathology of the eye, Ophthalmia, Vascular Coat). Sometimes differential diagnosis has to be made between X. and retinitis (see). It should be said that often both the choroid and retina are involved in the inflammatory process, so that X. can at the same time be combined with retinitis (chorioretinitis) and vice versa. In any case, chorioidal foci in the fresh state have a yellow or yellowish-red hue, turning in the late period into bright white atrophic spots (the sclera is visible through them). In chorioiditis, the pigmentation does not show a pronounced connection with the retinal vessels, is not located along their course, and does not change their course at the site of the chorioidal focus. Attempts are made to differentiate X. according to the etiological criterion. Thus, a syphilitic X. is distinguished, for which chorioiditis centralis (maculitis) is especially characteristic, although syphilis of the choroid can take another picture, indistinguishable from other X. (Mandel'shtam). The diagnosis of tuberculous X. can be made if solitary and miliary tubercles are present on the fundus, whereas the majority of X. of this etiological group show nothing specific and is diagnosed with greater or lesser probability only after general examination of the patient (Fuchs, Tovbin). Samylov noted displacement of pigment in chorioidal foci under the influence of tuberculin therapy, and he recommends keeping this focal reaction in mind for establishing the tuberculous origin of X.- A number of authors distinguish gonorrheal X. Thus, Maier among 238 cases of disseminated X. indicates gonorrheal cause in two. Hesse describes a case of chorioiditis gonorrhoica and recommends for accuracy of etiological diagnosis to widely use serological reactions for gonorrhea. In general, it should be said that in X. various etiological factors cause similar changes in the fundus, ophthalmoscopically difficult to distinguish from each other.-T r e a t m e n t. General-etiologic. In tuberculous X. - tuberculin therapy (with caution). Lukovskii obtained positive results in treating tuberculous X. with injections of creosote. Diaphoretic treatment. Locally-subconjunctival injections of sodium chloride, mercuric cyanide. Zamkovskii recommends subconjunctival injections of dionin, noting the best results in chorioretinitis and chorioiditis.