A comparison of direct and indirect video endoscopy.

The advent of microchip video cameras has opened another technology to endoscopy of the gastrointestinal tract: video endoscopy. With direct video endoscopy, the microchip camera is mounted on the distal tip of the endoscope; with indirect video endoscopy, a miniature camera is coupled to the eyepiece of a standard fiberoptic endoscope. Both systems view the procedure on a monitor. The systems were "bench" tested in an electronics laboratory to objectively compare resolution, brightness (luminosity), and color intensity (chroma). Clinical comparison was performed in 619 patients. Both video endoscopy systems provided significant advantages over fiberoptic endoscopes in therapeutic procedures, teaching, and documentation. The direct video system provided the best overall video image; the indirect system had a slightly diminished resolution and luminosity in both the "bench" test and clinical evaluation.