Page:Plates illustrating the natural and morbid changes of the human eye.djvu/28

22 Fig. 16. Inflammation of the greater 'part of the optic disc, and of a portion of the choroid and retina adjoining it. The grey-white and opaque part, in the middle of the Figure, represents the inflamed optic disc, which towards the right and downwards is seen to merge into an oval-shaped portion of the same colour, being the inflamed part of the retina and choroid. A narrow strip of healthy retina and choroid is represented round the opaque part.

The blood-vessels appear more or less indistinct in the inflamed optic disc.

Two thin blood-vessels, passing into the inflamed part of the retina, &c., are lost sight of in some, and appear thin and ill-defined in other places, while on reaching the healthy retina they again appear natural.

Fig. 17. The optic disc, &c. (of Fig. 16), represented after all inflammation had subsided. The optic disc, occupying the middle of the figure, still appears greyish-white and opaque (anæmic). (It continued so for 18 months after this drawing had been made.)

The retinal blood-vessels can be traced into the disc from all sides.

To the right and downwards from the optic disc we observe a group of brownish-black pigment spots upon a yellow patch; this indicates an atrophic condition of the previously inflamed parts. (Judging from the state of vision, the retina was destroyed at the atrophic part.)

Fig. 18. Extreme anæmia with atrophy of the optic disc, and of the tunics adjoining it (described by some as Retinitis pigmentosa).

The optic disc occupies the middle of the figure. Its centre appears white, the rest grey-white and opaque.

The blood-vessels of the retina which pass through the disc, are extremely thin, unequally dilated, and few in number. At some distance from the disc, in the retina, they are hardly perceptible.

The "retina " appears transparent. Beneath it we observe a