Atlas of rare ophthalmoscopic conditions : and supplementary plates to the atlas of ophthalmoscopy / by J. Oeller ; the text translated into English by Thos. Snowball.

  • Johann Nepomuk Oeller
Date:
1905
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Licence: In copyright

Credit: Atlas of rare ophthalmoscopic conditions : and supplementary plates to the atlas of ophthalmoscopy / by J. Oeller ; the text translated into English by Thos. Snowball. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    morrhages give rise to pigment that is visible with t]ie ophthal- moscope, it is nevertheless well known that, when the haemorrhages are very extensive, haematogenous pigment may develop in the retina in the form of patches either discrete or in groups.—The stage reproduced in this plate has evidently followed large, pro- hably frequently recuriing haemorrhages which, considering the patient's great age and the probability that the smaller vessels were diseased, are not surprising. The delicate tissue of the macula over a large area was destroyed by them. The large figure at the macula, therefore, should evidently be regarded as an area of necrosis, composed partly of dead retinal elements partly of fibrin. This stage can apparently continue for many months. Like all dead tissue, however, it acts as a foreign body which the organism endeavours to throw off and replace by living tissue. Leucocytes are attracted by chimiotaxis, and acting as phagocytes they bring about the absorption of the necrosed tissue. The yellowish-white spots whicli are now visible in the position of the disc-shaped figure after two years are very possibly largely made up of clumps of these phagocytes. Simultaneously with the absorption of the products of degeneration new connective tissue begins to develop from the neighbourhood of the figure, this tissue being destined to take the place of the dead matter which gra- ') Leber: The diseases of the retina and optic nerve. Unndbucli von Saemisch und Graefe. Vol. 5: Chap. 8. p. 559. dually disappears. Leber ^j draws attention to the development of pigmented cicatrices or layers of connective tissue after large extravasations, which may cover the surface of the retina. This change will probably take place in this case as it did in that in C. Tab. XXVH of my atlas, where a large shining-white cicatrix with striated edges and spots of pigment here and there could ultimately be seen in the place of the original figure. The two cases that I have observed have this peculiarity that the macular vessels have an abnormal course. The case G. Tab. XXVII showed an arterio-venous anastomosis, and in this case a macular branch from the inferior temporal artery and vein suddenly disappears about the centre of area, and no trace of them can be seen beyond this point. Both these vessels are much larger than other retinal vessels in this region. A very similar condition has already been depicted in C. Tab. Ill of this atlas from a case of albuminuric chorio-retinitis. Patches of exudation extending deep in the tissues or large haemorrhages at the macula, as the case may be, that destroy the layers of the retina which is specially delicate in this region seem to predispose to abnormalities in the course of the vessels in this way, that ad- hesion takes place between the retina and choi'oid, and vessels from the latter layer may grow into the former and even vice versa. Abnormalities of this kind have been hitherto very rarely seen with the ophthalmoscope, although they have from time to time been observed microscopically.