Anterior Segment Fluorescein Angiography Using a Modified Photo Slit-Lamp

Ophthalmic Photographer's Society, Fukui K, Yoshida A, Igarashi H, Cheng HM, Isobe H. The Journal of ophthalmic photography, 17(2), 1995, 54-60 authorWe modified a Zeiss Model-211 photo slitlamp by adding a fluorescein fundus photography barrier filter and compared its clinical usefulness for performing iris fluorescein angiography (FA) with two standard FA-capable photo slit-lamps, Zeiss 40-SL and Kowa SC-1200. We evaluated flash intensity, light transmission, filter transmission characteristics, density range on film in response to fluorescence, flash recharge time, and clinical applicability. We obtained the following results from Model-211, the 40-SL, and the SC-1200, respectively: maximum flash exposure, 500,000, 96,000, and 26,000 lux; light transmission from an objective lens through the camera, 350, 120, and 66 lux; minimum useful density of fluorescence, 0.9 x 10 7 , 0.4 x 10- 6 , and 0.8 x 10- 6 g/ml; and flash recharge time, 2.0, 6.0, and 1.0 seconds. The filter permeability rates of the three devices were similar. Small iris vessels were seen more clearly with the modified Zeiss Model-211 than with the other two systems, although the exposure with each magnification must be varied because of the changing light transmission with each magnification. We conclude that our system is clinically useful and superior to othercommercial units for imaging of small blood vessels. Fluorescein angiography (FA) of the anterior segment is widely used to evaluate disease progression and treatment efficacy [1-5]. This technique requires a filter designed for use in a photo slit-lamp and a high-intensity light source to replace the beamsplitter intended for stereoscopic viewing. The new light source must also allow rapid serial angiography. Since devices meeting these conditions are more expensive than conventional photo slit-lamps, their widespread use is limited. In the present study, we modified an existing photo slit-lamp (Model-211, Zeiss Jena, Oberkochen, Germany) by adding a fluorescein fundus photography barrier filter. We report herein the angiographic results from this low-cost modification compared with other commercially available FA-capable photo slit-lamps