On the development and abnormalities of the zonule of zinn / by E. Treacher Collins.

  • Collins, E. Treacher (Edward Treacher), 1862-1937.
Date:
[1892]
Catalogue details

Licence: Public Domain Mark

Credit: On the development and abnormalities of the zonule of zinn / by 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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    fiilly traced out, and the same may be said with regard to the zonule of Zinn. They are probably both foi-med by part of the same mesoblast as forms the vitreous humour (Lieberkiihn, Angelucci). All this leaves the matter very indefinite. My atten- tion was first directed to it by the examination of an eye- ball which had been enucleated from an infant aged three months, under the supposition that it contained a new growth. Pathological examination, however, re- vealed that the opaque mass behind the lens which had been taken for the growth was really a collection of cells and fibres into which a persistent hyaloid artery, still patent and carrying blood, passed and broke up. The chief interest of the specimen, however, centred in the fact that it exhibited the fibres of the suspensory ligament in all stages of theii- development; several of these are shown in Figs. 1 and 2. The fibres of the lens, instead of developing in their normal way, filling and rendering tense the capsule in which they were contained, had undergone retrogressive changes, and left the capsule lax and wrinkled. Whether this was the result of the per- sistence of the hyaloid artery, or whether it had persisted as the result of changes in the lens, I am unable to deter- mine. Anyhow, as the result of the lax condition of the capsule, the fibres of the suspensory ligament do not appear to have become stretched to theu- usual extent, and hence we have exhibited all stages of delayed develop- ment in them. The full details of this case are given at the end of this paper. I will now sketch what I find, from the examination of this eye, and from the examination of sections of several human foetal eyes, to be the course of events in the development of the zonule of Zinn, first briefly stating the steps preparatory to it. The process of cuticular epiblast, which dips in to form the lens, indents the primary optic vesicle, and at first lies in contact with what becomes the inner layer of the