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H Seidlitz

Publications and source records attributed to H Seidlitz.

4 recordsLinked to original sources
PubMed1990

Perspectives in "electronic endoscopy". Past, present and future of fibers and CCDs in medical endoscopes.

Electronic endoscopy has undergone considerable evolution in recent years. Early instruments had poorer resolution than fiberscopes, and distorted colors significantly. The second generation of electronic endoscopes has been considerably improved, and electronic endoscopy is expected to play a major role in endoscopy in the next decade, with its enhanced teaching abilities, permanent image storage, reproduction and retrieval. An important new development has been the development of a high-resolution colonoscope & gastroscope. Electronic endoscopes are now able to produce better resolution than fiberscopes, and the future should bring further improvements in resolution with electronic instruments. A number of problems still remain to be solved with electronic endoscopy. Irregular reflection from secretions, food and blood at short focus (less than 1 cm) results in a loss of resolution, which makes electronic endoscopy particularly difficult when bleeding is brisk. Electronic endoscopes synthesize color from a strobed signal of red, blue and green in a processor. Color is dependent on brightness, and at close focus, excessive brightness in the center of the field results in erratic color reproduction. Images acquired at electronic endoscopy may be digitized for storage and processing in a computer--which, however, is not a straightforward task at the present time. Image processing in electronic endoscopy is still in its early stages, but we anticipate that new developments in early diagnosis, classification and measurement of lesions will take place. Digitized images can also be transmitted via telephone lines, and it will soon be possible to instantaneously send images across the world.

Color↗
PubMed1989

Optical performance of electronic imaging systems for the colon.

Electronic (video) endoscopes are a significant new development in gastroenterology, offering the potential of enhanced teaching and permanent storage of pictorial data. The primary concern of gastroenterologists is the resolution and color performance of these instruments, as these parameters have important bearings on the ability to discern pathological changes in mucosa. We sought to determine the resolution and color capabilities of electronic colonoscopes and compare them with a conventional fiber colonoscope. Resolution was determined using a standard test chart at various distances and the number of picture elements (a measure of resolution) was calculated. The mean number of picture elements was Fujinon (219), Fiber (172), Pentax (169), Toshiba (142), Olympus (140), and Welch Allyn (133). In close focus examination (target distances less than 1 cm), the Fujinon and Toshiba endoscopes had significantly higher resolution than the other instruments. Color was measured quantitatively using a standard color chart and a color analyzer. Color polygons were plotted for each endoscope on a reference chromaticity diagram. All systems had an acceptable overall performance but color was undersaturated with some systems. The optical performance of electronic endoscopes has improved considerably since the inception of electronic endoscopy.

Colonoscopes↗