Use of sheet color filters for video-endoscopic observation during intraluminal photodynamic therapy

Background and Objective Photodynamic therapy (PDT) is currently evaluated in clinical studies for the treatment of bronchial and oesophageal tumors. Study Design/Materials and Methods Usually, a cylindrical diffuser is entered into the lumen via a flexible endoscope. Subsequently, the diffuser is positioned at the tumor location under direct‐ or video‐endoscopic vision and manually kept in position by the clinician during the treatment. However, video endoscopes are saturated (overexposure) due to the intense light from the diffuser tip and scattered light from the tissue. This hinders continuous monitoring of the diffuser position. Results A simple color filter sheet, suitable for use with endoscopes with removable CCD‐video head, appeared to be very effective in improving video endoscopic monitoring during treatment. Conclusion The standard fiberoptic endoscopes with the accessory CCD video head are more suitable for PDT treatment monitoring than modern endoscopes with the integrated CCD camera. © 1996 Wiley‐Liss, Inc.