Characterizing the 'gold standard' image for laparoscopic surgery

Background The term gold standard is often used to describe preferred display devices, frequently without substantiating evidence. A meaningful and objective measure of display quality for endoscopic surgery is required. Methods Typical colors from five tissue types were arranged in a striped pattern and displayed on four devices: a medical-grade cathode ray tube monitor, a liquid crystal display, a digital light projection display, and an obsolete cathode ray tube (CRT) monitor. The breadth and color contrast of the stripes were adjusted until the patterns became indiscernible to 12 subjects. The data provide a discernibility threshold. Results The liquid crystal display (LCD) monitor provided the best image. The medical grade and obsolete CRTs were second and third, respectively, and the projection display provided the most inferior image. Conclusions A meaningful and relevant measurement of image display quality for laparoscopic surgery based on the discernibility threshold is provided. Of the devices tested, the LCD is the best in terms of image, although the CRT may be preferred at off-axis viewing angles. The projection system, however, offers compensatory ergonomic advantages.