madman
Super Moderator
INTRODUCTION AND HISTORY
The history of laser medicine starts with Albert Einstein’s theory of stimulated emission, introduced in 1916. He postulated that when excited molecules/atoms interact with each other, they are able to stimulate the emission of new photons that are of a similar frequency, phase, and direction as the original atoms/molecules. This concept was used by early physicists, including TheodoreMaiman, to develop the earliest lasers. In 1963, Dr. Leon Goldman, a pioneer in laser medicine, first used a laser on human skin to treat melanoma. Dr. Goldman also used the continuous wave CO2 and argon lasers to treat port wine stains. 1 Although the lesions he treated lightened, they had high rates of scarring and complications due to the non-selective nature in which the laser energy was absorbed in the skin. The theory of selective photothermolysis, as elucidated by Drs. John Parrish and Rox Anderson propelled the use of lasers and forever changed the field of dermatology, and other medical specialties.2 The concept of selective photothermolysis refers to localized, “selective,” destruction of the desired target by combining a selective wavelength that is absorbed by the target chromophore and a pulse duration that is equal or shorter than the thermal relaxation time of the target chromophore. The combination of these 2 notions allows for more precise control of thermal energy and allows for more focused destruction. With the advent of selective photothermolysis, the treatment of unwanted pigment, tattoos, and hair became possible. We went from non-selective lasers to early versions of both ablative and non-ablative lasers. Additional applications became possible with the advent of fractional photothermolysis.3 The laser beam can be applied fully to the tissue, or it can be delivered in a pixilated pattern, called fractional photothermolysis (FP). FP can use both ablative and nonablative wavelengths of light. This fractional injury is seen in the form of microscopic treatment zones (MTZ) that often form a grid pattern of injury on the skin. This allows for the sparing of normal tissue between each MTZ, and a shorter treatment recovery time. Interestingly, up to 50% of the tissue can be destroyed during FP without causing scarring or necrosis. By creating multiple laser holes in the skin, FP has been also used as a new method for drug delivery. This expansion continues with advances in technology and technique. Herein, we provide a review of updates in lasers as they are used in dermatology to treat a variety of medical and aesthetic conditions.
*Vascular Lasers
*Hair Removal
*Tattoos
*Pigmentation/Pigmented Lesions
*Scars
*New Devices
Although there have been so many recent advances and updates in laser technology and its applications, there are continually new devices and applications in the pipeline. One promising development is a newer 3-dimensional (3D) laser that has been FDA-cleared and will be commercially available in the United States soon. This 3D laser is highly focusable allowing laser energy to be targeted at precise depths in the dermis with reduced fluences at the epidermis. The reduced energy at the epidermis will make this a safer device for the skin of color patients. Additionally, there will be a high-resolution, high-speed imaging system that will be paired and integrated with the laser. This imaging system will not only allow mapping and guidance during treatment but also pretreatment and post-treatment skin changes to be archived, making way for a more personalized laser treatment for every patient.
Other devices modifications that may be on the horizon in the future include the integration of robots into dermatology. These laser “robots” may be programmed by humans, however, the action itself will be executed by robot software. Such a laser “robot” may be useful in skin cancer surgery, where we can perform image-guided laser ablation. Another way to integrate robots into lasers may be fractional-laser robots. These laser robots may be able to penetrate the skin at any precise depth and target several imageable structures such as sweat glands, nerves, cells, tumors, etc. These ablative fractional robot lasers may even be used for very precise drug delivery. The future remains very bright when it comes to the emergence of new technology that will advance our ability to treat a variety of medical and cosmetic dermatologic conditions.
The history of laser medicine starts with Albert Einstein’s theory of stimulated emission, introduced in 1916. He postulated that when excited molecules/atoms interact with each other, they are able to stimulate the emission of new photons that are of a similar frequency, phase, and direction as the original atoms/molecules. This concept was used by early physicists, including TheodoreMaiman, to develop the earliest lasers. In 1963, Dr. Leon Goldman, a pioneer in laser medicine, first used a laser on human skin to treat melanoma. Dr. Goldman also used the continuous wave CO2 and argon lasers to treat port wine stains. 1 Although the lesions he treated lightened, they had high rates of scarring and complications due to the non-selective nature in which the laser energy was absorbed in the skin. The theory of selective photothermolysis, as elucidated by Drs. John Parrish and Rox Anderson propelled the use of lasers and forever changed the field of dermatology, and other medical specialties.2 The concept of selective photothermolysis refers to localized, “selective,” destruction of the desired target by combining a selective wavelength that is absorbed by the target chromophore and a pulse duration that is equal or shorter than the thermal relaxation time of the target chromophore. The combination of these 2 notions allows for more precise control of thermal energy and allows for more focused destruction. With the advent of selective photothermolysis, the treatment of unwanted pigment, tattoos, and hair became possible. We went from non-selective lasers to early versions of both ablative and non-ablative lasers. Additional applications became possible with the advent of fractional photothermolysis.3 The laser beam can be applied fully to the tissue, or it can be delivered in a pixilated pattern, called fractional photothermolysis (FP). FP can use both ablative and nonablative wavelengths of light. This fractional injury is seen in the form of microscopic treatment zones (MTZ) that often form a grid pattern of injury on the skin. This allows for the sparing of normal tissue between each MTZ, and a shorter treatment recovery time. Interestingly, up to 50% of the tissue can be destroyed during FP without causing scarring or necrosis. By creating multiple laser holes in the skin, FP has been also used as a new method for drug delivery. This expansion continues with advances in technology and technique. Herein, we provide a review of updates in lasers as they are used in dermatology to treat a variety of medical and aesthetic conditions.
*Vascular Lasers
*Hair Removal
*Tattoos
*Pigmentation/Pigmented Lesions
*Scars
*New Devices
Although there have been so many recent advances and updates in laser technology and its applications, there are continually new devices and applications in the pipeline. One promising development is a newer 3-dimensional (3D) laser that has been FDA-cleared and will be commercially available in the United States soon. This 3D laser is highly focusable allowing laser energy to be targeted at precise depths in the dermis with reduced fluences at the epidermis. The reduced energy at the epidermis will make this a safer device for the skin of color patients. Additionally, there will be a high-resolution, high-speed imaging system that will be paired and integrated with the laser. This imaging system will not only allow mapping and guidance during treatment but also pretreatment and post-treatment skin changes to be archived, making way for a more personalized laser treatment for every patient.
Other devices modifications that may be on the horizon in the future include the integration of robots into dermatology. These laser “robots” may be programmed by humans, however, the action itself will be executed by robot software. Such a laser “robot” may be useful in skin cancer surgery, where we can perform image-guided laser ablation. Another way to integrate robots into lasers may be fractional-laser robots. These laser robots may be able to penetrate the skin at any precise depth and target several imageable structures such as sweat glands, nerves, cells, tumors, etc. These ablative fractional robot lasers may even be used for very precise drug delivery. The future remains very bright when it comes to the emergence of new technology that will advance our ability to treat a variety of medical and cosmetic dermatologic conditions.