Clinical use of transillumination.

Transillumination of fluid-filled intracranial pathology in infants and small children has been discussed in recent reports (Calliauw, 1961;Dodge and Porter, 1961;Shurtleff, 1964).The threefold purpose of this communication is (1) to describe a method for both quantitation and easy recording of observed transillumination, (2) to emphasize the detection of potentially curable intracranial lesions, and (3) to stress the usefulness of transillumination in detecting and evaluating fluid-filled lesions in body areas, other than the skull. MethodOthers have described methods for transillumination photography that are both time consuming and somewhat variable in results (Dodge and Porter, 1961; Cambem and Shurtleff, 1961;Taylor, Dent, Lynch, and Alexander, 1956).For the past few years we have been recording cases on High Speed Ektachrome, Daylight ASA 160, using a single lens reflex camera.The transillumination light is an 800 watt second Ascor Spotlight (Fig. 1) projected through a Cooke 2 in.f/18 lens in place of the usual fresnel lens (Fig. 1).In this manner the light can be 'coned down' with no escape and the beam condensed with little loss.The fill light is a 200-watt second strobe (Fig. 1) with blue filter bounced from ceiling or wall and triggered by a photocell (Fig. 1) within the transilluminating spotlight head (Fig. 1).The cool blue tones resulting from the blue filtered light record the reddish areas of trans- illumination much more realistically than would be the case if normally balanced light were used.Exposure is one flash at f/5 -6 orf/8, depending on the amount of transillumination observed.Since the speed of the strobe obviates the effect of any movement, it is possible to hand-hold the camera and struggling child without loss of clarity.Room lights may be left on. ResultsA standardized light source, time of exposure, and recording device obviate the variables inherent in