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Laparoscopic and endoscopic surgery rely uniquely on high quality display of acquired images, but a multitude of problems plague the researcher who attempts to reproduce such images for educational purposes. Some of these are intrinsic limitations of current laparoscopic/endoscopic visualization systems, while others are artifacts solely of the process used to acquire and reproduce such images. Whatever the genesis of these problems, a glance at current literature will reveal the extent to which endoscopy suffers from an inability to reproduce what the surgeon sees during a procedure. The major intrinsic limitation to the acquisition of high-quality still images from laparoscopic procedures lies in the inability to couple directly a camera to the laparoscope. While many systems have this capability, this is useful mostly for otolaryngologists, who do not maintain a sterile field around their scopes. For procedures in which a sterile field must be maintained, one trial method has been to use a beam splitter to send light both to the still camera and the digital video camera. This is no solution, however, since this results in low quality still images as well as a degradation of the image that the surgeon must use to operate, something no surgeon tolerates lightly. Researchers thus must currently rely on other methods for producing images from a laparoscopic procedure. Most manufacturers provide an optional slide or print maker that provides a hardcopy output from the processed composite video signal. The results achieved from such devices are marginal, to say the least. This leaves only one avenue for possible image production, the videotape record of an endoscopic or laparoscopic operation. Video frame grabbing is at least a problem to which industry has applied considerable time and effort to solving. Our own experience with computerized enhancement of videotape frames has been very promising. Computer enhancement allows the researcher to correct several of the shortcomings of both laparoscopic video systems and videotapes, namely color imperfections, scanline problems, and lack of image resolution for later display. We present a history of laparoscopic imaging, the current state of the art, and future prospects for high-resolution images from laparoscopic and endoscopic systems.
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