Laser (light amplification by stimulated emission of radiation) surgery is used to treat a variety of skin conditions. It involves the use of lasers that cut, seal or vaporize skin tissue and blood vessels in the affected area.

Lasers have been used surgically for several decades. However, they were typically avoided in the past because they often caused adverse affects (e.g., scarring). Current laser technology and increased understanding of how lasers interact with skin tissue enables physicians to accurately target specific areas of the skin, without harming surrounding tissue, and lower the risk for these complications.

Certain parts of the skin called chromophores absorb the light from the laser when it is directed at the skin. When this occurs, physical, mechanical, chemical or temperature changes occur inside the tissue of the affected area. This often removes or diminishes the unwanted growth or marking with little or no lasting adverse affects.

In order for a laser to be produced, a large number of electrons must be “excited.” Most lasers use intense flashes of light or electrical discharges to initiate this process. The electron settles after being excited and releases energy in the form of photons (light energy). The photon that is emitted has a specific wavelength (color) that is determined by the energy level of the electron. The wavelength is measured in nanometers (one billionth of a meter) and describes a laser’s intensity. Higher measurements indicate stronger lasers and lower measurements indicate lasers that are less intense.

The light a laser produces is much different than ordinary “white” light, which is weak and travels in many different directions. Lasers produce strong, concentrated light that is organized (coherent), with each photon moving in unison with the others.

Currently, no single laser is available that can be used for all cosmetic and noncosmetic skin conditions. In addition, the patient's skin type and hair color, as well as the location of the area being treated, may affect the physician's choice of laser. Some of the more commonly used lasers include:

• Pulsed lasers. Each of these lasers falls into one of three subcategories:
  
  
• • Pulsed dye lasers (PDL). The treatment of choice for spider veins, rosacea, and various other skin conditions. Ultra-long or variable pulsed-dye lasers (e.g., V-Beam) are capable of treating larger areas of skin with fewer side effects.
    
    
  • Pulsed KTP lasers. Used to treat vascular (pertaining to blood vessels) skin conditions. Pulsed KTP lasers slowly heat the affected blood vessels for long durations allowing the vessels to cool without rupturing.
    
    
  • Long-pulsed infrared laser. Primarily used to treat leg vein disorders that affect the skin. Long-pulsed infrared lasers emit a longer wavelength, penetrating farther into the skin than other lasers.
    
    
• CO2 (carbon dioxide) lasers. These include the high-powered pulsed CO2 laser, which is used for procedures that require deep penetration of the skin.
  
  
• Er:YAG laser. Used for more superficial procedures (e.g., skin resurfacing).
  
  
• Red-light or IR-light systems. Commonly used for hair removal. There are numerous types of lasers that can be used to remove unwanted body hair. Different types may be better suited depending on patient skin and hair color.
  
  
• Continuous-wave lasers. Commonly used until the mid 1980s. They are less popular today because of an increased risk for scarring and skin discoloration as opposed to more modern lasers.
  
  
• Quasicontinuous-wave lasers. Also used frequently in the past to treat many different skin conditions. However, they are not as popular today because of an increased likelihood of scarring.
  
  
• Q-switched lasers. Used to treat or remove superficial and deep pigmented (colored) lesions, tattoo ink and pigment-related skin abnormalities.

In addition, a highly versatile laser–like device known as the intense pulsed light (IPL) source may be used to treat large areas of skin for cosmetic (e.g., hair removal) and noncosmetic procedures (e.g., removal of varicose veins). The IPL can be used extensively because it produces pulsed light at a variety of pulse durations and intervals. However, more treatments of longer durations, as well as a higher degree of expertise by the operator tend to be necessary with the IPL source compared to other lasers.