Disclaimer: The information contained within the Grand Rounds Archive is intended for use by doctors and other health care professionals. These documents were prepared by resident physicians for presentation and discussion at a conference held at Baylor College of Medicine in Houston, Texas. No guarantees are made with respect to accuracy or timeliness of this material. This material should not be used as a basis for treatment decisions, and is not a substitute for professional consultation and/or peer-reviewed medical literature. Cutaneous Lesions and the Use of the CO2 Laser In the span of just over 30 years, lasers have become a common part of everyday life. Besides the research laboratory, this technology has become the cornerstone of the communication, manufacturing and audiovisual industries. We come in contact with or use lasers daily, whether in grocery stores as bar scanners, or listening to music using a compact disk player. The medical use of lasers has also mushroomed. This technology has been applied to almost every area of Otolaryngology - Head and Neck surgery, frequently with phenomenal results. Often patients ask about the use of lasers in the treatment of their problems thinking that this is the "twenty-first century" technology is better than more traditional treatment methods for every problem. Yet, is this actually true? One area that exemplifies the use of lasers in Otolaryngology, and an area in which data are available to compare to more traditional treatment methods, is the use of lasers in the treatment of cutaneous lesions. All forms of laser energy represent light energy. Light is a complex system of radiant energy composed of small energy bundles known as photons. Lasers in medical use employ radiation or radiant energy within the light or optical portion of the electromagnetic spectrum. Laser is an acronym for Light Amplification by the Stimulation of Emission of Radiation. The underlying idea of all lasers is the concept of stimulated emissions developed by Einstein. This theory states that an energized particle or atom can "dump" this stored energy into a light beam passing through these stimulated particles. A particle's energy is effectively transferred to the photons within the light beam. There are four components to all lasers: the laser medium; the resonating tube (chamber), the amplifier, and the power supply. Two essential components are the laser medium and the resonating chamber. The medium of each laser is the particle through which the light beam passes and is unique to each type of laser. It is also the components for which each laser system is named. A Laser medium can be a gas, a liquid, or a solid. The most commonly used material in the practice of otolaryngology is CO2. The chamber houses the laser medium and contains the amplification system that is usually a combination of mirrors. As the photons of light pass through the laser, medium energy is transferred to the light beam. The mirrors at either end of the chamber not only intensify the beam energy level, but also select those beams that are parallel (the same wavelength), unidirectional (columnated), and in phase (coherent). These properties give lasers immense power and precision. Laser wavelength is a function of the medium. Each wavelength interacts differently with living tissue. Lasers in medical use emit radiant energy in the visible and infrared region of the electromagnetic spectrum. The basic effect of all lasers on tissue is that of a photothermal reaction. There is a balance between wavelength absorption and scatter within tissue that varies with each laser medium. As the wavelength of the laser medium decreases, the amount of tissue scatter increases. The level of absorption or scatter is also governed by the absorption spectrum of the tissue components. The tissue component with the same wavelength as the laser being used will be affected most by the laser energy. Thus, the laser can be chosen which corresponds to a certain tissue type. For example, the argon laser emits photons of 488 to 514 nm. This visible, blue-green light is absorbed preferentially by pigmented tissues such as hemoglobin and melanin. It is, therefore, an excellent tool to use for the treatment of vascular and pigmented lesions. In contrast, the CO2 does not have a specific chromophore with which it preferentially interacts. It is a more versatile laser because it is absorbed by intracellular and extracellular water. The CO2 laser produces radiant energy at a wavelength of 10,600 nm. It is an infrared beam and is not visible. A second, coaxial beam must be used with this laser to guide the invisible beam. Usually a helium-neon laser is used as a pointing beam. The one significant drawback of this system is the fact that it cannot be transmitted via fiber-optic, flexible tubing. This makes the system cumbersome. Lasers can be used either as a precision cutting instrument or as a vaporizer. One can easily change between these modes by focusing or defocusing the beam. The laser creates a characteristic wound. The target tissue is quickly heated over 100 degrees Celsius. This causes rapid vaporization of cellular water that, in turn, causes the cells to explode. Two distinct zones of tissue damage are created. The zone of vaporization and necrosis is devoid of all viable tissue. This zone extends approximately 100 um. Surrounding this area is the zone of thermal conductivity and repair extending another 300 to 500 um. It is within this outer zone the vessels, lymphatics, nerves 0.5 mm or less are sealed instantaneously. The vaporization of tissue and the instantaneous coagulation of vessels make laser systems unique cutting and hemostatic instrument compared to conventional methods. When comparisons are made to other forms of surgical intervention, there are three advantages to using the laser system that are commonly listed in the literature. It is thought to be superior to other systems for hemostasis and edema. It is a noncontact system that theoretically can reduce the potential for wound infection. Finally there is minimal damage to surrounding tissue, therefore inducing less scarring, and improving wound healing. Comparison studies have been performed in animal models to examine laser - tissue vs. scalpel - tissue interactions. Studies have shown that the laser wound is almost 40% weaker, hypocellular, and contains less collagen than a scalpel induced wound for the first three weeks after surgery. Further, Bailin and coworkers reported no difference in final appearance of the wound when the two were compared. Initial data on the effects of the laser on scar formation suggested that the laser induced less scarring. As longer follow-up became available on patients treated with laser systems again no difference could be found between laser and scalpel induced wounds. The one area in which laser technology enjoys a distinct advantage is in the treatment of premalignant lesions. Multiple studies suggest that the CO2 system offers superior cosmesis, decreased recurrence rates, and decreased morbidity compared to more conventional techniques. Laser systems, however, are not the preferred surgical tool in oncology. Adams and Price reported their experience with the excision of 24 superficial basal cell carcinomas of the head and neck region. Twelve of the lesions recurred within a 3 to 12 month follow-up period. Perhaps the best study comparing and contrasting the use of the laser and scalpel for benign conditions was completed by Har-El in 1993. He reviewed 23 patients with rhinophyma. Sixteen patients underwent laser excision, and seven patients were treated with scalpel excision. They found that intraoperative time was longer with the use of the laser. There was no difference between techniques in terms of tissue preservation, need for skin grafting, amount of scarring, or the level of immediate postoperative pain. The laser was superior in terms of hemostasis, overall satisfaction, and pain level during the first week after the procedure. The difference in pain levels during the first week was due to the need for more wound manipulation when the scalpel technique was employed. All laser systems have inherent risk associated with this advanced technology. These issues must be carefully considered. The CO2 system is classified as a class VI laser, the most dangerous category allowed for medical use. Associated hazards are grouped into either direct or indirect. It must be stressed that these are risks not only for the patient, but for each member of the operating team. Direct hazards include direct beam related problems. This includes skin burns, eye injuries and laser fires. Eye damage is rare with the CO2 laser system because the beam is absorbed by water and penetrates no further than the cornea. Direct hazard preventions include proper warning signs, nonreflective operative equipment, wavelength-specific eye protection, protecting exposed skin, and approved laser safe endotracheal tubing. Prescription glasses provide adequate protection for CO2 systems, but goggles are preferred as they provide superior and lateral eye protection. Indirect hazards include the smoke generated from tissue vaporization. The smoke, or laser plume, can be directly toxic or contain viable cells and even viruses. Viral DNA has been retrieved from the laser plume in very small quantities and the infectious potential of this material is still debated. The key precaution for indirect hazards is the use of laser safety masks and the use of the proper smoke evacuator equipment at all times while the laser is in use. Newer laser masks can filter 0.1 mm particles with 95% efficiency. Case Presentation A 62-year-old white male with a history significant only for well controlled hypertension presented with an approximately 5 year history of redness and intermittent tenderness over the nasal tip area. Over the ensuing years he noticed gradual, nodular enlargement of the skin of his nose. When this condition became noticeable to his friends and family members, he presented Otolaryngology clinic for evaluation. He was diagnosed with rhinophyma. Incomplete excision of the lesion was then performed using the CO2 laser system. At 3 week's follow-up, he was doing well and was pleased with the early cosmetic results. Bibliography Abramson AL, DiLorenzo TP, Steinberg BM. Is papillomavirus detectable in the plume of laser-treated laryngeal papilloma? Arch Otolaryngol Head Neck Surg 1990;116:604-607. Achauer BM, Vander Kam VM. Vascular lesions. Clin Plast Surg 1993;20:43-51. Adams EL, Price NM. Treatment of basal cell carcinoma with carbon dioxide laser. J Dermatol Surg Oncol 1979;5:803-806. Airway fires: reducing the risk during laser surgery. Health Devices 1990;19:109-139. Bailin PL, Tarz JL, Wheeland RG. Laser therapy of the skin: a review of principles and applications. Otolaryngol Clin North Am 1990;23:123-164. Bandieramonte G, Chiesa F, Lupi M, Marchesini R. Laser microsurgery in oncology: indications, techniques and results of 5-year experience. Lasers Surg Med 1987;7:478-486. Ben-Baruch G, Fidler JP, Wessler T, Bendick P, Schellhas HF. Comparison of wound healing between chopped model-superpulse mode CO2 laser and steel knife incision. Lasers Surg Med 1988;8:596-599. Buell BR, Schuller DE. Comparison of tensile strength in CO2 laser and scalpel skin incisions. Arch Otolaryngol 1983;109:465-467. Colles MJ. What is a laser and how is it applied for therapy. Br J Hosp Med 1988;40:111-114. David LM. Laser vermilion ablation for actinic cheilitis. J Dermatol Surg Oncol 1985;11:605-608. Dufresne RG, Garrett AB, Bailin PL, Ratz JL. Carbon dioxide laser treatment of chronic actinic cheilitis. J Am Acad Dermatol 1988;19:876-878. Ferenczy A, Bergeron C, Richart RM. Human papillomavirus DNA in CO2 laser-generated plume of smoke and its consequences to the surgeon. Obstet Gynecol 1990;75:114-118. Fitzpatrick RE, Goldman MP, Dierickx C. Laser ablation of facial cosmetic tattoos. Aesth Plast Surg 1994;18:91-98. Fitzpatrick TB, Pathak MA. Historical aspects of methoxsalen and other furcoumarins. J Invest Dermatol 1959;32:229-303. Garden JM, Geronemus RG. Dermatologic laser surgery. J Dermatol Surg Oncol 1990;16:156-168. Garden JM, O'Banion K, Shelnitz LS, Pinski KS, Bakus AD, Reichmann ME, et al. Papillomavirus in the vapor of carbon dioxide laser-treated verrucae. JAMA 1988;259:1199-1202. Greenbaum SS, Krull EA, Watnick K. Comparison of CO2 laser and electrosurgery in the treatment of rhinophyma. J Am Acad Dermatol 1988;18:363-368. Hanke CW. Lasers in dermatology. Indiana Med 1990;83:394-402. Healy GB, Strong MS, Shapshay S, Vaughan C, Jako G. Complications of CO2 laser surgery of the aerodigestive tract: experience of 4416 cases. Otolaryngol Head Neck Surg 1984;92:13-18. Hukki H, Krogerus L, Castren M, Schroder T. Effects of different contact laser scalpels on skin and subcutaneous fat. Lasers Surg Med 1988;8:276-282. Keller GS, Razum NJ, Elliott S, Parks J. Small incision laser lift for forehead creases and glabellar furrows. Arch Otolaryngol Head Neck Surg 1993;119:632-635. Landthaler M, Haina D, Brunner R, Waidelich W, Braun-Falco O. Effects of argon, dye, and Nd:YAG lasers on epidermis, dermis, and venous vessels. Lasers Surg Med 1986;6:87-93. Laser use and safety. Health Devices 1992;21:306-310. McBurney EI. Dermatologic laser surgery. Otolaryngol Clin North Am 1990;23:77-98. Morrow DM, Morrow LB. CO2 laser blepharoplasty: a comparison with cold-steel surgery. J Dermatol Surg Oncol 1992;18:307-313. Morrow DM. Re: carbon dioxide laser blepharoplasty - advantages and disadvantages. Ann Plast Surg 1992;28:397-398. Norris JE. The effect of carbon dioxide laser surgery on the recurrence of keloids. Plast Reconstr Surg 1991;87:44-53. Oosterhuis JW, Verschueren RC, Eibergen R, Oldhoff J. The viability of cells in the waste products of CO2-laser evaporation of cloudman mouse melanomas. Cancer 1982;49:61-67. Ossoff RH. Laser safety in otolaryngology - head and neck surgery: anesthetic and educational considerations for laryngeal surgery. Laryngoscope 1989;99(Suppl 48):1-26. Ossoff RH, Reinisch L. Laser surgery: basic principles and safety considerations. In: Cummings CW, Krause CJ. Otolaryngology - Head and Neck Surgery, 2nd ed. St. Louis: Mosby, 1993:199-212. Sawchuk WS. Infectious potential of aerosolized particles. Arch Dermatol 1989;125:1689-1692. Sawchuk WS, Weber PJ, Lowy DR, Dzubow LM. Infectious papillomavirus in the vapor of warts treated with carbon dioxide laser or electrocoagulation: detection and protection. J Am Acad Dermatol 1989;21:41-49. Shapshay SM, Rebeiz EE. Lasers in Otolaryngology. In: Cummings CW, Fredrickson JM. Otolaryngology - Head and Neck Surgery, 2nd ed. St. Louis: Mosby, 1993;2100-2121. Stern JC, Lucente FE. Carbon dioxide laser excision of earlobe keloids: a prospective study and critical analysis of existing data. Arch Otolaryngol Head Neck Surg 1989;115:1107-1111. Weisberger EC, ed. Lasers in Head and Neck Surgery. New York: Igaku-Shoin, 1991. Wenig BL, Weingarten RT. Excision of rhinophyma with Nd:YAG laser: a new technique. Laryngoscope 1993;103:101-103. Wheeland RG. Cutaneous laser surgery: an update. Otolaryngol Clin North Am 1990;23:165-170. Wheeland RG, Bailin PL, Ratz JL, Roenigk RK. Carbon dioxide laser vaporization and curettage in the treatment of large or multiple superficial basal cell carcinomas. J Dermatol Surg Oncol 1987;13:119-124. Whitaker DC. Microscopically proven cure of actinic cheilitis by CO2 laser. Lasers Surg Med 1987;7:520-523. Grand Rounds Archive | Department Home page BCM Public | BCM Intranet | Privacy Notices | Contact BCM | BCM Site Map | ©2001-2006 Baylor College of Medicine
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