It is ironic now to think that in 1958, when American scientist Charles Townes showed that a MASER could theoretically be made to operate in the visible region of the spectrum, his colleagues told him "that his work would have little relevance to the real world". The year was 1958, the 'hula hoop' was all the craze in Europe and Russian author Boris Pasternek declined the Nobel Prize in Literature as he feared the authorities would expel him from his motherland. I am sure the world had changed a lot when Charles Townes received the Nobel Prize in Physics four years later. Today, lasers are used in every aspect of life including a ever increasing number of cosmetic treatments, including skin resurfacing for wrinkle reduction and acne scars, removal of tattoos, removal of hair, removal of pigmented blemishes (age spots and moles) and the treatment of vascular lesions (port wine stains and spider veins).
In fact the real story of lasers started many years before. In the year of 1917, the great physicist, Albert Einstein postulated that atoms could be persuaded to emit tiny packets of energy called 'photons' in his treatise "On the Quantum Theory of Radiation." This sentinel piece of physics laid the groundwork for the theory of stimulated emission of radiation, which was later used by the by American physicist, Gordon Gould to coin the acronym LASER. In essence, the word is an abbreviation of the phrase light amplification by stimulated emission of radiation.
The year was 1957 and the Russians had just launched Sputnik 1 into the skies above a horrified US nation. Senator Lyndon Johnson spoke for the nation when he said "soon, they will be dropping bombs on us from space like kids dropping rocks onto cars from freeway overpasses!". The newspaper headlines of the day reflected his fear when one stated, "Soviet satellite circles globe every 90 minutes". In that year, plans were made to start the space race and America ushered in a new age of political, military, technological, and scientific developments. The Government formed the Pentagon's Defense Advanced Research Projects Agency and huge grants were poured into private and public laboratories across the United States to fund the creation of a new spacecraft and the first working laser.
In 1960, their efforts paid off when a physicist called Theodore Maiman working with the Hughes Electric Corporation in California, created the world's first working Ruby laser. The acronym LASER, although appearing theoretical is of more than passing interest, because it means a laser device must be able to make a new form of light. This light must be composed of one wavelength (colour), it must pass in one direction (coherent) and its waves must be parallel. These unique characteristics can be used by doctors to achieve different results. We know the different wavelengths can penetrate various depths of skin and they can also cause dissimilar effects by targeting differing coloured lesions. This means that laser A could be used to target haemoglobin (red) in the broken blood vessels (telangiectasia) of rosacea, while laser B may be used to target melanin (brown) in the hair on an upper lip of a female with hirsuitism. It also means that lasers could be used to vapourise water in tissues, thereby causing resurfacing and later collagen stimulation with significant improvements to wrinkles in the skin.
In 1961, research was focused on this new technology continued with the production of a new laser made from crystals of yttrium-aluminum-garnet treated with 1-3% neodymium. The worlds first Nd:YAG laser was developed. This laser emitted energy in the near infrared (IR) spectrum at a wavelength of 1060 nm. Although many Americans felt safer to have more powerful lasers being developed, doctors tried to harness its power as they found its high-penetration emission to be useful for vapourising tissues and thermally coagulating large blood vessels. It is interesting to see that the laser is still widely used in cosmetic medicine today. It has even found a new role targeting hair follicles in darker coloured skin. The following year, the first experiments into depilation by laser took place when Dr. Leon Goldman used the principle of selective target destruction with ruby lasers in an attempt to destroy the melanin in hair follicles.
Unfortunately for him, although the idea was good, he did not take into account that the laser emitted a continuous wave more adept at shooting down Sputnik and it also targeted melanin in the skin and burnt his patients. The other patients in the experiment suffered from post inflammatory hyperpigmentation and the experiment was abandoned. In that year, the argon laser was also developed. This laser emitted energy in the blue-green portion of the visible spectrum, making it more readily absorbed by melanin and hemoglobin than by the surrounding tissue. It was 1962 and the American public waited with baited breath as President Kennedy and Soviet Premier Nakita Khrushchev waged a battle of nerves over the Cuban missile crisis.
In 1963, the ruby laser became the first medical laser when Francis L'Esperance from the Columbia- Presbyterian Medical Centre used it to coagulate retinal lesions. In 1965 he began working with Bell researchers Eugene Gordon and Edward Labuda to design a better laser for eye surgery as the blue-green light of the argon laser is more readily absorbed by blood vessels than the red light of the ruby laser. After further refinements and experiments, they developed a laser that is still used to this day to treat patients with diabetic retinopathy. It also has a use in the treatment of port-wine stains. As the cold war developed, the US Government funded projects that covered research into more powerful lasers, ones that had the power to cut through steel.
In 1964, Patel at Bell Laboratories developed the CO 2 laser. This laser operated at 10,600 nm and it was similar to the Nd YAG in that it could be used for cutting materials like stainless steel. The advantage was that it could also be focused onto a smaller spot; a function that one day could be useful in space. Thankfully for cosmetic medicine at this wavelength, energy is also heavily absorbed by water, which everyone knows is the primary constituent and chromophore of cells in living tissue. This particular function made the energy generated by the new CO2 laser suitable for tissue vapourisation and a whole new era of wrinkle removal by skin resurfacing began. The experiments on trying to find the 'Holy Grail' of being able to remove hair by laser light followed the path of the emerging Beatles throughout most of the rest of the sixties.
In 1967, while Dr. Chris Barnard carried out the world's first human heart transplantation at the Groote Schuur hospital in Cape Town, attempts made to reduce the potential damage to background skin by directing the light energy to individual follicles through the use of a wire-thin fibre optic apparatus. Many of these devices were sold illegally in the United States throughout the late sixties until the FDA banned their use. In 1968, Union Carbide's commissioned a study by Dermascan (manufacturer of the Proteus thermolysis machine) of the effects of applying laser energy applied directly to each hair follicle. The results were largely unsuccessful in that the perceived depilation may have been related to a type of electrolysis effect. Today the company is more famous, for those three nights in 1984, their chemical plant in Bhopal, India, began leaking 27 tons of the deadly gas methyl isocyanate into the atmosphere exposing half a million people to the gas, resulting in the eventual deaths of 20,000 people.
During the 1970's research into finding a means of hair removal with laser continued with Omnicron Corporation producing a photo epilator that used coherent light to epilate hair. The device never produced marketable results and things remained that way until another attempt was by Lasertron inc. in the 1980s when they used an Argon laser to direct energy at the haemoglobin surrounding individual hairs. The device was marketed before proper clinical tests were done to establish its efficacy and before long patients were complaining as it proved to be unsuccessful for permanent hair removal. In 1983, Oshiro and Maruyama noted that hair was lost from after pigmented nevi were treated with a ruby laser. Whenever the increased the laser power to affect the hair follicles, the epidermis became severely damaged. These observations led to Anderson and Parrish developing the theory of 'selective photothermolysis'. This theory was based on the fact that a laser of particular wavelength and pulse duration of light could be used to target a particular chromophore, selectively destroying it while sparing the surrounding tissue. The space race started by the launch of Sputnik continued and in that year, Sally Ride, the first American female astronaut landed aboard the Challenger space shuttle.
While tumultuous things were happening on the world stage, including the fall of the Soviet Empire, the freeing of Nelson Mandela and Saddam Hussein's fateful annexation of Kuwait, the development of laser hair technology seemed to have reached an impasse. There were some highlights when Thermolase Corporation built and tested a low-power Nd: YAG laser for the removal of tattoos and birthmarks.
During the mid nineties the quest to find the 'Holy Grail' laser seemed to quicken when a company called ThermoLase used a topical suspension of carbon particles applied to skin followed by treatment of a Q-switched variant of this Nd: YAG laser called the SoftLight(TM) to treat hair. The laser certainly produced some results and within a short time it received FDA approval and became the first device for hair removal in the United States. ThemoLase went all out to market the product and within a short period they starting using the device in a chain of clinics called Spa Thira. It soon became apparent that this was not the 'Holy Grail' laser as the device seemed to only delay hair regrowth by 3-4 months, but it did not provide permanent hair reduction. This led to several lawsuits against the company and in the period1998-99; they closed most of their spas.
However, all was not lost for TheroLase because it is apparent that many clients who had unsuccessful hair-removal reported improvement in their skin's texture. It appeared the heat emitted by the laser in association with a lotion that was employed caused a form of skin resurfacing. Before long, Thermage exploited this benefit by obtaining FDA approval for SoftLight(TM) resurfacing, marketing it as a safe, fast and effective alternative to CO2 and erbium skin resurfacing.
In 1994, Nelson Mandela became President of South Africa. It was the same year that Doctors Anderson and Grossman working with Palomar Medical Technologies, first used a water-cooled delivery handpiece during epilation with a long pulsed Ruby laser. The laser was developed at Massachusetts General Hospital and the chilled head meant the laser did not thermally damage the surrounding skin, leaving it less irritating than other methods and relatively pain free. This EpiLight ® Ruby laser is still in use in many US clinics today.
In 1995, the world was gripped by the live television coverage of the Los Angeles trial of a former American football star and actor 'O.J.Simpson'. Further upstate in the small town of Los Gatos, dermatologist Patrick Bitter had other things on his mind. He postulated that if he used a Xenon flashlight to emit broad-spectrum light made up of multiple wavelengths, he could use a cutoff filter to restrict the bandwidth to a certain range. By applying different filters, he could imitate laser action by using the shorter wavelengths to clear pigment spots (lentigines) and broken vessels (telangiectasias) and the longer ones rejuvenate and smooth the skin. By using a range of wavelengths and some clever software a company could produce a device that could cure many ailments at once. In these moments the new concepts of Intensed Pulsed Light (IPL) and photorejuventation were born and the world moved closer to finding the 'Holy Grail' laser. Ironically, these devices would not be real lasers, as they were in reality flash lamps giving off white light, similar to that of a light bulb with wavelengths in the range of 400- 765nm.
In 1998, ESC Sharplan announced the introduction of the Vasculight ® and the concept of IPL ® technology for photorejuvenation. In the year 2000, this company became Lumenis and they introduced the Quantum SR as the pioneer IPL of the new Type I Photorejuvenation procedure.
By 2001, numerous companies began to produce IPL machines and market the photorejuvenation procedure. Later that year some of the people who had helped form ESC/Lumenis scientists created a new company called Syneron. In 2002, this company announced the introduction of the Aurora RF, a new type of laser that promised to enhance photorejuvenation by using the addition of RF (bipolar radiofrequency) to the pulsed light source. This action brought both companies into the U.S. District Court with Lumenis bringing a preliminary injunction against Syneron's sale of Aurora devices. In 2004, Lumenis granted Syneron unlimited non-exclusive worldwide licenses for Lumenis patents relating to the use of incoherent light in aesthetic and medical applications, including all of its IPL related patents. It was the same year that a tsunami spread throughout the Indian Ocean, killing nearly a fifth of a million people and devastating coastal communities across South and South East Asia.
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