USE OF SHEET COLOR FILTERS FOR VIDEO-ENDOSCOPIC OBSERVATION DURING INTRALUMINAL PHOTODYNAMIC THERAPY

Background and Objective: Photodynamic therapy (PDT) is currently eval uated in clinical studies for the treatment of bronchial and oesophage al tumors. Study Design/Materials and Methods: Usually, a cylindrical diffuser is entered into the lumen via a flexible endoscope. Subsequen tly, the diffuser is positioned at the tumor location under direct- or video-endoscopic vision and manually kept in position by the clinicia n during the treatment. However, video endoscopes are saturated (overe xposure) due to the intense light from the diffuser tip and scattered light from the tissue. This hinders continuous monitoring of the diffu ser position. Results: A simple color filter sheet, suitable for use w ith endoscopes with removable CCD-video head, appeared to be very effe ctive in improving video endoscopic monitoring during treatment. Concl usion: The standard fiberoptic endoscopes with the accessory CCD video head are more suitable for PDT treatment monitoring than modern endos copes with the integrated CCD camera. (C) 1996 Wiley-Liss, Inc.