How to use the ophthalmoscope : being elementary instructions in ophthalmoscopy, arranged for the use of students / by Edgar A. Browne.

Browne, Edgar A. (Edgar Athelstane), 1841-1917.

Date:: 1883

Credit: How to use the ophthalmoscope : being elementary instructions in ophthalmoscopy, arranged for the use of students / by Edgar A. Browne. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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$uiidistinguishable by its colour from the surrourid- incr fundus, aud its situation has to be made out by the convergence of the central vessels. The disc is unnaturally white in anaemia and atrophy. Some practice is required to distinguish the two conditions. In^ansemia the rest of the fundus is.Jtale. and lights up badly. The central vessels are badly filled, but their relative size is not affected. The surface of the disc not sunken, and the white- ness is due to the abstraction of pink alone, so^' that in the erect imasie the nerve can he distin-~ guished frQ.m.the porus opticus and sclerotic border. Both eyes are equally affected. In atrophy the fundus_(by contrast) loo]i:s ^yen rec[derMthan_ no^^^ The arteries are small, and in late stages generally reduced in number, the veins in the early stage dilated, in the later shrunken, and uiidistinguishable from the arteries; the surface of the disc shelving {v. Atrophic Cup) with the margin, at first ragged (in the variety following inflammation), but afterwards sharp and even. The whiteness is due both to the abstrac- tion of pink and the transparent grey of nerve- substance, with the addition of tendinous glisten- ing fronj increased connective tissue, the whole re- sulting in a staring bluish-white, like skim-mill^i _ s$