Carbon dioxide laser in surgery

this book about the laser and its applications in medicine specially in surgery, with example of pilonidal sinus excision. laser is an acronym for "light amplification by stimulated emission of radiation". A laser differs from other sources of light in that it emits light coherently, spatially and temporally. Spatial coherence allows a laser to be focused to a tight spot, enabling applications such as laser cutting and lithography. Spatial coherence also allows a laser beam to stay narrow over great distances (collimation), enabling applications such as laser pointers. Lasers can also have high temporal coherence, which allows them to emit light with a very narrow spectrum, i.e., they can emit a single color of light. Temporal coherence can be used to produce pulses of light as short as a femtosecond. The carbon dioxide laser (CO2 laser) was one of the earliest gas lasers to be developed. It was invented by Kumar Patel of Bell Labs in 1964. Carbon dioxide lasers have become useful in surgical procedures because water (which makes up most biological tissue) absorbs this frequency of light very well.