Lasers

What are lasers?

“Laser” is an acronym that denotes “Light Amplification by the Stimulated Emission of Radiation.”  The first laser was created by Theodore Maiman in 1960 of the Hughes Aircraft Research Laboratories.  This ruby laser was based on Albert Einstein’s 1917 theory of stimulated emission of radiation.  Lasers are unique in that they are artificially created beams of energy that possess intense brightness, can travel long distances, and can be harnessed in millions of ways in our everyday life.

How do lasers work?

There are presently over 1000 materials that can create a beam of light, but only around a dozen or two that are clinically used in medicine or aesthetic applications.  Lasers can be created from a variety of sources and are usually named after the components that create this specialized light energy. Common sources or “mediums” are gases, crystals, liquid, and diodes. Laser light can be a visible or an invisible form of energy. Lasers can be in the ultraviolet, visible, or infrared bands of light that make up the electromagnetic spectrum of energy. This specialized light is made up of tiny particles of energy known as photons.  Photons travel in waves called waveforms and make up the various types of energy that we know of today.  

What are medical lasers commonly used for?

Most common medical lasers are heat driven in nature and the laser energy (or light) is absorbed by a specific entity or target in the body.  This absorption of the laser energy by a particular target or chromophore is usually directed toward blood, water, pigment, or collagen.  In the medical and surgical practice, lasers can be used to cut and vaporize tissue and coagulate or seal blood vessels.  Lasers can also be pulsed at very high megawatt powers and be emitted in pulses at a billionth of a second to create a shock wave effect to break up stones in the bladder and ureters.  It also can be used photoacoustically in ophthalmology to open clouded membranes in the eye that can occur after cataract surgery and in dermatology and plastic surgery to break up tattoo ink to facilitate tattoo removal.

In aesthetic and cosmetic practices, the theory of “selective photothermolysis” is commonly utilized.  This concept is applied by the selection of a specific band of light (time the light is delivered to the tissue) and by using a specific energy level, to treat various pigmented lesions, acne, scars, unwanted hair, blood vessels, and much more without thermal injury or damage to the surrounding tissue.

What are the benefits of lasers?

The ability to produce highly precise and controllable effects on tissues,  easy adaptability to fiberoptics, microscopes  and minimally invasive delivery systems, and the potential to literally treat some conditions by shining a highly controllable beam of light on a specific target without touching the tissue with a solid instrument,  make these devices unique. These versatile devices have been used to provide solutions for diagnostic and therapeutic problems and offer the scientist and clinician the opportunity to tailor strategies to fit specific and unique scenarios. Lasers allow one to accomplish more complex tasks. Proper use can reduce blood loss, decrease post operative discomfort, reduce the chance of wound infection, decrease the spread bacteria or of some cancers, minimize the extent of surgery in selected circumstances, and result in better wound healing. They are useful in both open and minimally invasive procedures. These devices are interchangeable to some degree, assuming that the proper delivery device and parameters are selected.

Advances in lasers for medicine

Research and experimental studies are constantly advancing the development of new wavelengths of laser light in the medical and cosmetic field.  New laser light delivery systems using fiber optics are on the nanometer (billionth of a meter) scale and are now being researched in the treatment of a variety of diseases and medical conditions.  It is just a matter of time until laser light will become a common tool in the fight against cancer, diabetes, high blood pressure, and heart disease.