Page:Plates illustrating the natural and morbid changes of the human eye.djvu/25

Rh Fig. 10. The region of the yellow spot, showing the appearance observed during syphilitic choroiditis.

(This form of choroid inflammation has by some been termed choroiditis disseminata, from the foci of inflammation ("lymph nodules") being separated from each other by apparently healthy portions of choroid).

The roundish, yellow, tolerably well-defined spots (seven in number) represent nodules of lymph situated in and upon the choroid.

The groups of black and brown spots of pigment, situated upon and surrounded by light yellow portions of choroid (one of which is represented in the middle of the figure), are portions of choroid in a state of atrophy. The atrophic portions of choroid shade off into more vascular ones.

The group of pigment spots in the middle of the figure occupies the part of the choroid which subtends the yellow spot of the retina. Similar groups, termed atrophic patches, are expected to appear where the lymph nodules are visible at present.

Branching over the choroid, we observe a few thin, unequally dilated blood-vessels of the retina. Their distribution, calibre, and number at the region of the yellow spot is not quite in accordance with health, and indicates a participation of the retina in the morbid changes of the choroid.

Towards the right of the figure is represented a large blood-vessel of the choroid, running through a yellowish atrophic portion of that tunic, and disappearing beneath a group of pigment spots.

Fig. 11. Chronic "syphilitic" inflammation of the choroid and retina (Inherited syphilis.)

The optic disc and the tunics immediately adjoining it.

The optic disc (represented in the middle of the figure) has a yellowish turbid colour. It appears very ill- defined, through the adjoining retina and choroid having likewise lost their transparency. The few blood-vessels which pass from the optic disc into the retina are extremely thin. They are lost sight of in some parts of the retina; in