Congenitally malformed cystic eye, causing extensive protrusion of upper eyelid, and complete extrusion of conjunctival sac through the palpebral fissure / by S. Johnson Taylor and E. Treacher Collins.

  • Taylor, S. Johnson.
Date:
[1906]
Catalogue details

Licence: In copyright

Credit: Congenitally malformed cystic eye, causing extensive protrusion of upper eyelid, and complete extrusion of conjunctival sac through the palpebral fissure / by S. Johnson Taylor and E. Treacher Collins. 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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    and its inner wail of degenerate retinal tissue, to be de- scribed directly, there is tissue containing blood-vessels more or less widely spaced out, but devoid of any pig- mented cells. This probably represents attenuated choroid. Inner wall of cyst.—The inner lining tissue of the cyst varies in different parts of the specimen. Nowhere is there any retina with well differentiated layers, and nowhere can those parts of the retina, which are developed from the two layers of the secondary optic vesicle, be found lying in apposition. On the inner surface of the portion of choroid which is well developed, and of the rudimentary ciliary pro- cesses in which it terminates, a layer of pigment epithelial cells presenting their normal appearance is seen. This layer forms part of the lining wall of the cyst, there being no retina on its inner surface. Covering the greater portion of the solid mass of tissue which protrudes into the cavity of the cyst from below, and which, as will be mentioned later, is atypically de- veloped vitreous humour, is a layer of epithelial cells. They resemble those of the outer layer of the retina, but are devoid of pigment, except for a few granules here and there. This slight tendency to pigmentation, and their continuity with the pigment epithelium already described, serve to show that they really represent the outer layer of the secondary optic vesicle. The inner wall of the greater portion of the cyst, ami of all its anterior part, consists of a degenerate kind (if retina. It is composed of a close network of delicate fibres with branching cells and nuclear bodies, like those met with in the nuclear layers of the retina. The partition proceeding backwards from the anterior wall of the cyst, and partially dividing its cavity into two parts (PI. VI, fig. 1), is seen to be composed of two layers of membrane of this description, with fibrous tissue con- taining numerous blood-vessels between them, the latter being evidently of mesoblastic origin. I