There is a controversy regarding which has been developed first between lasers for pigmented lesions and lasers for vascular lesions. Lasers for pigmented lesions were already mentioned in papers published in 1960s, and some of them mentioned hair removal too. Alexandrite laser and dye lasers for pigmented lesions(ex; Pigmented lesion Dye Laser (PLDL)) have a longer history. However, when considering the extent of systematic development, it would be more helpful to mention the lasers for vascular lesions first for better understanding, which is also why I am mentioning it first. This is probably because the vascular lasers could achieve innovative therapeutic effects that could not be achieved earlier in some of vascular lesions. Pigmented lesions, on the other hand, can be treated with a satisfactory outcome just by electrocautery, such as Bovie, or by TCA chemical peeling, without even using a laser. It can be said that the lasers for pigmented lesions started to be developed systematically, later than the vascular lasers, from the moment when it was used for treating dermal melanosis (nevus of Ota or nevus of Ito) that were nonresponsive to conventional treatments.
When skin lasers for destroying blood vessels are arranged in the order of market release, regardless of the order of development by physicists, the order would be argon laser, dye laser, copper vapor laser, KTP and Nd:YAG, and Alexandrite laser. Dye laser can destroy blood vessels without damaging the adjacent tissues, and can be said as the most important one among others. Vascular lasers are broadly divided to those with and without the concept of Selective Photothermolysis by R. Rox Anderson. In order to destroy blood vessels selectively, the theory can be satisfied by using wavelengths, such as 418, 542 and 577nm, which can be absorbed better into oxyhemogloblin than melanin. In practice, however, the depth and the size of the target works as obstructive factors, and a number of lasers have evolved diversely, apart from these wavelengths.
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Understanding the sequence and reasons of development from the past and understanding why such changes in wavelengths and pulse duration have occurred would be helpful for better clinical application of vascular lasers. Determining the optimal vascular laser for each skin problems that are made up of blood vessels or that are treatable by destroying the blood vessels distributed throughout the lesion (such as Port wine stain, Telangiectasia, various Hemangiomas, Sebacious Hyperplasia, Verruca, Facial flushing, Rosacea, Scar, Keloid, Varicose vein, Venouslake and Stria distensae) would be the most important basic knowledge as well.
Development of the first vascular lasers was mostly centered around Boston area in USA.. Most of the developed vascular lasers were imported into Korea, but the problem was that each laser had advantages and disadvantages, making it impossible for a clinic to deliver the best treatment for all kinds of vascular diseases. This might be also one of the reasons why dermatologists lost confidence in vascular lasers. One might think that a newly developed laser device should have a better therapeutic effect in every aspect. In practice, however, the previous device may be better suited for a specific disease or condition. Moreover, some diseases do not require a special know-how about the procedure, contributing to the present complex state of medical community where clinicians can perform laser therapies even without full understanding of skin diseases or the skin itself enough to make an accurate diagnosis. In Korea, the distribution of vascular lasers seems dwindling with time due to the issues such as side effects, efficacy and insurance coverage. Nevertheless, the development process of vascular lasers is highly important, because it can be the basic knowledge for general understanding of lasers.
SPTL-1//b 585nm 450us
It is helpful to understand the relationship among R. Rox Anderson and Horace Furumoto, OT Tan, Candela Corporation, Cynosure and Wellman Laboratory to learn about vascular lasers. Let’s find out about their roles and related history from their papers, before looking into the device itself. It is not too much to say that the early development phase was focused on the treatment of nevus flammeus (Port wine stain or Nevus Flameus)
Wellman Center for Photomedicine at MGH Harvard Medical School
Once called the Wellman Laboratory of Photomedicine, this laboratory focused on the research of light that affects human biology and development of diagnosis and treatment devices using light. The laboratory was established upon the contribution of Mr. and Mrs. Wellman. It has grown in size by John Parrish, and now R. Rox Anderson is the director of the laboratory. The Wellman Center for Photomedicine played a decisive role in the development of skin laser therapies and is still playing a central role in preliminary studies and clinical studies of various lasers, with the Beckman Laser Institute of UC Irvine, where J. Stuart Nelson is the medical director.
Horace Furumoto
After graduating Ohio State University, he participated in the development of weapons using laser. In 1970, he established Candela Corporation and worked there for 19 years as CEO. He also founded Cynosure in 1991 and worked as a CEO until September 2003.
This Japanese American man is also known as the one who developed high-power dye laser, and has laid the foundation for a number of skin lasers that are currently used. After having a conflict with investors, he resigned from 19-years of work as a CEO of Candela and founded Cynosure in 1991. He had a crucial effect on the early study of R. Rox Anderson, who established the concept of Selective Photothermolysis. However, the two men did not seem to get along very well and left only few papers or traces of working together. It is speculated that the two men worked on laser studies together at the Wellman Laboratory of Photomedicine for a certain period of time from the end of 1970s through 1980 (e.g., Effect of dye laser pulse duration on selective cutaneous vascular injury. Garden JM, Tan OT, Kerschmann R, Boll J, Furumoto H, Anderson RR,Parrish JA. J Invest Dermatol. 1986 Nov;87(5):653~7).
The reason of lasers made by Candela and Cynosure still have many similarities is probably because the two companies were founded by the same person. Being a CEO and physicist, he made creative and durable lasers, although overall completeness may be lacking in some cases because he could not receive much help from clinicians or laboratories. He died at the age of 76 on July 9, 2007. The American Society of Laser Medicine and Surgery (ASLMS) awards research projects every year in memory of him.
[Tip]
History of Dye Laser by Candela Corporation
SPTL-1a : 585nm 450us 5mm spot
SPTL-1b : 585nm 450us, 7mm spot
SPTL-2: 585nm, 590nm, 595nm, 600nm(tunable) 0.45~1.5ms true long pulse.
Sclerolaser
ScleroPlus: increased spot size
ScleroPlus HP: abbreviation of High Power, increased Max Fluence, addition of DCD
(Dynamic Cooling Device)
VBeam : 595nm, 0.45~40ms DCD, Stuttered, not True Long pulse(4 sub-pulses)
VBeam Perfecta: 8 sub-puldes
OT Tan
She is a Chinese doctor, graduated from a medical school in the UK. She is the main author of the early clinical studies about dye laser for the treatment of vascular lesions. She was once a rival dermatologist of R. Rox Anderson. After working at the laser center of Boston University, she went back to the clinic again in the mid ‘80s and has been working as a practitioner in Boston. Below listed are the representative studies that can be helpful for understanding vascular dye lasers. As you can see, her studies are in line with the development of vascular dye lasers.
- Histologic responses of port-wine stains treated by argon, carbon dioxide, and tunable dye lasers. Apreliminary report. Tan OT, Carney JM, Margolis R,Seki Y, Boll J, Anderson RR, Parrish JA. Arch Dermatol.1986 Sep; 122(9):1016~22.
- Tunable pulsed dye laser for the treatment of benigncutaneous vascular ectasia. Polla LL, Tan OT, GardenJM, Parrish JA. Dermatologica. 1987 ;174(1): 11~7;577nm, 360us.
- The treatment of port-wine stains by the pulsed dyelaser. Analysis of pulse duration and long-term therapy.Garden JM, Polla LL, Tan OT. Arch Dermatol. 1988Jun; 124(6): 889-96.; 577nm, 20us or 360us.
- Treatment of children with port-wine stains usingthe flashlamp-pulsed tunable dye laser. Tan OT,Sherwood K, Gilchrest BA. N Engl J Med. 1989 Feb 16;320(7): 416~21.; 577nm.
- 585nm for the treatment of port-wine stains. TanOT, Morrison P, Kurban AK. Plast Reconstr Surg. 1990Dec; 86(6): 1112~7; 577nm와 585nm 비교
- The next article will focus on the detailed history of dye lasers, including argon laser, copper vapor laser and dye laser of Candela Corporation, in chronological order.
- To be continued -
▶ Previous Artlcle : #1. Naissance of Cutaneous Laser
▶ Next Artlcle : #3. Development of Vascular Laser Ⅱ-1
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