Lacrimal obstruction in the young / by Donald Gunn.

  • Gunn, Donald.
Date:
1900
Catalogue details

Licence: In copyright

Credit: Lacrimal obstruction in the young / by Donald Gunn. 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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    be due to some developmental fault, resulting in a failure of the duct to complete itself by opening into he inferior meatus of the nose. This explanation, assuming its correctness, suggests the following queries :— (1) What is the histological nature of the tissues obstructing the lower end of the duct ? (2) Is there any secretion and passage of tears dur- ing foetal life ? (3) If not, what is the material that collects and causes distension of the lacrimal passages ? (i) The mucous lining of the nose—derived from the surface epiblast—is the last structure to be per- forated by the growth of the lumen of the duct, and must of necessity form one, if not the sole, constituent of any obstruction left by the failure of this process to complete itself. In the adult we know that the lower extremity of the duct is formed by the mucous mem- brane, which at this point often makes a more or less complete valve across the opening. It is, therefore, probable that in most cases the fault is due to a per- sistence of the continuity of the mucous membrane at this point. The rapid cure following the passage of a probe in some of the cases quoted (Nos. 2, 5, 6) points to the obstruction having been thin and membranous. At the same time, we must not lose sight of the pos- sibility of the cartilages being at fault, for at birth the cartilages representing the lacrimal, superior maxillary, and inferior turbinate bones bound the duct more or less completely, being thickest towards the lower end of the duct where it is crossed by the turbinate. Lastly, in the nose of a foetus there are cartilages present which disappear entirely later on, and are not permanently represented by any bone in the adult skull. One such is a layer that connects the caiiila- ginous ethmoid above with the lateral cartilage of the nose below.