METHOD FOR KERATOGRAPHIC RECORDING

FINCHAM (1953) gives the history of keratography and discusses its value in ophthalmology. Commercially-produced apparatus to fulfil the functions described are marketed under the names Zeiss Corneal Reflectograph (Jeffreys, 1953) and A.I.M. Photo-Keratoscope (Hansell, 1956). Stein (1958) describes an apparatus which he has produced for photo-keratography. It is not our intention to review this excellent work, but to give details of the methods employed in our department. Procedure Apparatus.-A target similar to that described by Fincham (Fig. 1) was pro-duced by making a stencil and painting it on to a circular piece of medium opal Perspex 8-75 " in diameter. The main body of the apparatus was made from two 9 " diameter cake tins, and the light source was a circular cold cathode tube, made by a local company engaged in the manufacture of neon signs. FIG. 1.-Fincham type target. The camera used was a 35-mm. Exakta single lens reflex with extension tubes and an adapter to accept the optical component, a 50 mm. f.3 5 Berthiot Stellor enlarging lens. A small amount of metal work to fit the components together, was carried out in the hospital workshops. The Perspex target was fitted into the base of one cake tin, which had had a hole 8 " in diameter cut in the bottom, and the cold cathode tube was attached to the interior of the other cake tin by spring clips (Fig. 2). A camera extension ring with the Exakta fitment was then attached to the rear of the tin. The lens and the lens hood were connected to the * Received for publication August 17, 1960