Safety Issues in Laser Surgery
The introduction of lasers into the medical environment poses several unique problems, as with electrical or electronic equipment. Potential hazards of electrical shock exist requiring appropriate grounding, and other electrical safety procedures are essential. However, there are no particular unique electrical safety problems associated with laser use and biomedical engineers and bioelectronic technicians familiar with safe installation of electrical and electron equipment in hospital and health care environments should have no difficulty in providing guidance for the safe electrical use of laser equipment. As already said in the first chapter, the use of proper radiometric terminology and interaction mechanisms is recommended. Unfortunately, the misuse of radiometric terms such as fluence (for radiant exposure) and fluence rate (for irradiance) continue in the literature. These two terms should only be used for flux densities in tissue. The principal radiometric concepts used to describe laser-tissue interactions and the laser interaction mechanisms used in laser surgery are represented in Figures 1 and 2, respectively the dosimetric terms and the laser tissue interactions; approximate thresholds for laser interactions as a function of pulse duration are shown in Figure 3. Since thresholds actually depend also somewhat upon focal image size, the above values are only approximate and represent values developed from extensive research on laser retinal injury.
KeywordsLaser Beam Stratum Corneum Surgical Laser Occupational Exposure Limit American National Standard Institute
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