Cooperative Phenomena in Two‐pulse, Two‐color Laser Photocoagulation of Cutaneous Blood Vessels ¶

A novel laser system has been developed to study the effects of multiple laser pulses of differing wavelengths on cutaneous blood vessels in vivo, using the hamster dorsal skin flap preparation and in vitro, using cuvettes of whole or diluted blood. The system permits sequenced irradiation with well‐defined intrapulse spacing at 532 nm, using a long‐pulse frequency‐doubled Nd:YAG laser, and at 1064 nm, using a long‐pulse Nd:YAG laser. Using this system, we have identified a parameter space where two pulses of different wavelengths act in a synergistic manner to effect permanent vessel damage at radiant exposures where the two pulses individually have little or no effect. Using a two‐color pump–probe technique in vitro, we have identified a phenomenon we call green‐light–induced infrared absorption, where a pulse of green light causes photochemical and photothermal modifications to the chemical constituents of blood and results in enhanced infrared absorption. We identify a new chemical species, met‐hemoglobin, not normally present in healthy human blood but formed during laser photocoagulation which we believe is implicated in the enhanced near‐infrared absorption.

[1]  A. Welch,et al.  Is there an optimal laser treatment for port wine stains? , 1986, Lasers in surgery and medicine.

[2]  H. H. Comly Cyanosis in Infants caused by Nitrates in Well Water. , 1945 .

[3]  Photothermal removal of telangiectases of the lower extremities with the PhotodermVL. , 1998, Journal of the American Academy of Dermatology.

[4]  C Chothia,et al.  Haemoglobin: the structural changes related to ligand binding and its allosteric mechanism. , 1979, Journal of molecular biology.

[5]  J. Parrish,et al.  Microvasculature Can Be Selectively Damaged Using Dye Lasers: A Basic Theory and Experimental Evidence in Human Skin , 1981, Lasers in surgery and medicine.

[6]  D. Green Photothermal sclerosis of leg veins. , 1997, Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.].

[7]  Joseph A. Izatt,et al.  Study of bone ablation dynamics with sequenced pulses , 1991, Photonics West - Lasers and Applications in Science and Engineering.

[8]  J. Langerholc,et al.  Thermodynamic analysis of laser irradiation of biological tissue. , 1978, Applied optics.

[9]  R. Anderson,et al.  The optics of human skin. , 1981, The Journal of investigative dermatology.

[10]  A. Welch,et al.  Determining the optical properties of turbid mediaby using the adding-doubling method. , 1993, Applied optics.

[11]  J. Izatt,et al.  In vivo bidirectional color Doppler flow imaging of picoliter blood volumes using optical coherence tomography. , 1997, Optics letters.

[12]  Treatment of spider veins using a 10 millisecond pulse-duration frequency-doubled neodymium YAG laser. , 1999, Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.].

[13]  Kenneth A. Schenkman,et al.  Visible and Near Infrared Absorption Spectra of Human and Animal Haemoglobin , 2002 .

[14]  S. L. Jacques The Role of Skin Optics in Diagnostic and Therapeutic Uses of Lasers , 1991 .

[15]  F. Frank,et al.  Endoscopic Application Of The Nd: YAG Laser In Urology, Biophysical Fundamentals And Instrumentation , 1980, Other Conferences.

[16]  B. Zelickson,et al.  Treatment of leg telangiectasia using a long‐pulse dye laser at 595 nm , 1997, Lasers in surgery and medicine.

[17]  J. Pickering,et al.  Double-integrating-sphere system for measuring the optical properties of tissue. , 1993, Applied optics.

[18]  Gary D. Noojin,et al.  A Comparison Of Various Probit Methods For Analyzing Yes/No Data On A Log Scale. , 1996 .

[19]  Gracie Vargas,et al.  Laser Fluence for Permanent Damage of Cutaneous Blood Vessels , 1999, Photochemistry and photobiology.

[20]  A. Roggan,et al.  Optical Properties of Circulating Human Blood in the Wavelength Range 400-2500 nm. , 1999, Journal of biomedical optics.

[21]  Wim Verkruysse,et al.  Optical Absorption of Blood Depends on Temperature during a 0.5 ms Laser Pulse at 586 nm , 1998, Photochemistry and photobiology.

[22]  R. Weiss,et al.  Early clinical results with a multiple synchronized pulse 1064 NM laser for leg telangiectasias and reticular veins. , 1999, Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.].

[23]  T. Milner,et al.  Cryogen Spray Cooling during Nd:YAG Laser Treatment of Hemangiomas A Preliminary Animal Model Study , 1997, Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.].

[24]  B. Dibernardo,et al.  Laser hair removal: where are we now? , 1999, Plastic and reconstructive surgery.

[25]  Max F. Perutz,et al.  Science Is Not a Quiet Life: Unravelling the Atomic Mechanism of Haemoglobin , 1998 .

[26]  Comly Hh Landmark article Sept 8, 1945: Cyanosis in infants caused by nitrates in well-water. By Hunter H. Comly. , 1987 .

[27]  K R Diller,et al.  Microscopic instrumentation and analysis of laser-tissue interaction in a skin flap model. , 1989, Journal of biomechanical engineering.