Diseases of the larynx / by J. Gottstein ; translated and added to by P. M'Bride.

  • Jacob Gottstein
Date:
[1885?]
Catalogue details

Licence: Public Domain Mark

Credit: Diseases of the larynx / by J. Gottstein ; translated and added to by P. M'Bride. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    of the mirror, and, us the field of vision increases, it is proportionatelj' easier to see the whole interior of the larynx at once. Tlie liandle should be 2 millimetres in diameter and about 15 or 20 centimetres in ¥iG. G. a. Laryngeal luirrois. 0. Diagrams showing the size of the reflecting surface of mirrors 1, 2, 3. length; it is composed of metal and sufficiently resistant not to bend during examination, while it terminates in a handle of wood or ivory about 10 centimetres long. It is better for the stem and handle to be immovably fastened together; but, in order to make laryngoscopic cases convenient and to enable one handle to serve for mirrors of different sizes, the stem may be fastened to the handle by a screw. ]\Ietallic mirrors are now hardly ever used, for, althougli tliey give a more accurate image, still their employment is fraught with too mucli inconvenience; thus they become dim from the slightest moisture, are easily spoilt by contact ■with medicated solutions, and get scratched in cleaning. Among glass mu-rors so much use- less material is offered for sale that we would recommend a careful examination to the intending purchaser. The glass must be white, so that white paper is reflected white and not green or blue ; the thickness of the mirror should be a little over 1 millimetre ; and the metal setting should be firmly adapted to the edge of the reflecting surface. Mirrors with very flexible stems are unsuitable, and the handle should not be too thin or smooth so that it can readily be held in the operator's hand. AVe consider round mirrors as all sufficient and have seen no advantage from the use of oval or quadrilateral varieties. Magnifiers and api)liances for measMing the laryngeal image have been adapted to mirrors, but the results are not satisfactory and can certainly be dispensed with in practice, so that we need not consider them fiu-ther. A good and accurately applied illumination is of such importance towards obtaining a clear laryngeal image that the success of a laryngo- scopic examination is altogether dependent upon it. In this everything hinges not only upon the strength of the light but also upon its accurate application. The physical law which must be taken into consideration is that the rays of light which impinge upon a plane mirror are so reflected that the angle of reflection and the angle of incidence are equal. In order to illuminate the interior of the larynx, we must, therefore, hold the mirror against the posterior wall of the