DISEASES OF THE CHORIOID 131 



chorioiditis; however, diseases of these eoats do appear 

 to exist independently, and when the chorioid alone is 

 inflamed it is called chorioiditis. The distinction is made 

 by the retinal vessels, without a break, passing over the 

 chorioidal lesion. 



The chorioid is a portion of the uveal tract extending 

 forward and including the ciliary body and iris, and 

 these bodies are often inflamed in conjunction with the 

 chorioid, when it is known as iridochorioiditis. These 

 are the parts first affected in recurrent ophthalmia. 



The chorioid is a vascular and pigmentary coat, with 

 supporting connective tissue, and is subject to simple 

 and inflammatory affections. It rests upon the white 

 sclera, and for this reason rupture of the coat can be 

 easily seen, as can the crescentic rupture near the 

 papifla in cases of high myopia. 



The early stages of chorioiditis are manifest by various 

 spots of a yellowish-white color due to exudates, when 

 the retinal vessels may be seen passing over them. 

 Later, by a proliferation of pigment, these spots appear 

 black, particularly about the borders. There is always 

 a disturbance of vision, with a sensation of flashes of 

 light, with marked scotomata. The causes are syphihs, 

 scrofula, tuberculosis, and diseases of the blood. In 

 cases of high myopia the chorioid suffers many changes 

 by reason of severe stretching. 



According to the location and distribution of the spots 

 or lesions, chorioiditis is known as central, disseminated, 



