You are in: eMedicine Specialties > Dermatology > PHYSICAL MODALITIES INCLUDING LASER APPLICATIONS Cutaneous Laser Resurfacing: Carbon DioxideArticle Last Updated: Nov 13, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 10
 
Author: Robert S Bader, MD, Assistant Clinical Professor, Department of Dermatology, Hahnemann Hospital Robert S Bader is a member of the following medical societies: American Academy of Dermatology, American Society for Dermatologic Surgery, and American Society for MOHS Surgery Editors: Tina S Alster, MD, Clinical Professor, Department of Dermatology, Georgetown University School of Medicine; Director, Washington Institute of Dermatologic Laser Surgery; Michael J Wells, MD, Associate Professor, Department of Dermatology, Texas Tech University Health Sciences Center; Mary Farley, MD, Dermatologic Surgeon/Mohs Surgeon, Department of Dermatology, The Skin Surgery Center; Glen H Crawford, MD, Assistant Clinical Professor, Department of Dermatology, University of Pennsylvania School of Medicine; Chief, Division of Dermatology, The Pennsylvania Hospital; William D James, MD, Paul R Gross Professor of Dermatology, University of Pennsylvania School of Medicine; Vice-Chair, Program Director, Department of Dermatology, University of Pennsylvania Health System Author and Editor Disclosure Synonyms and related keywords: laser peel, carbon dioxide laser resurfacing, CO2 laser resurfacing, laser peeling, carbon dioxide laser peel, CO2 laser peel, skin resurfacing, facial, wrinkle treatment, wrinkle reduction, scar treatment, scar reduction INTRODUCTIONSection 2 of 10
 
Over the past decade, advances in laser technology have allowed cosmetic surgeons to diminish the appearance of scars and wrinkles using both ablative and nonablative lasers. Until recently, surgeons relied on chemical peeling, dermabrasion, surgical scar revision, electrosurgical planing, and dermal/subdermal filler substances (eg, collagen implantation, silicone injection, autologous fat transplantation) for the correction of scars and wrinkles. Today, physicians use 5 laser modalities for ablative skin resurfacing:
Each of these treatments relies on the principles of selective photothermolysis in order to selectively target water-containing tissue and effect controlled tissue vaporization. HISTORY AND GENERAL OVERVIEWSection 3 of 10
The carbon dioxide laser became available in 1964 and soon became the most widely used laser in dermatologic practice. The carbon dioxide laser emits an invisible infrared beam at a 10,600-nm wavelength, targeting both intracellular and extracellular water. When light energy is absorbed by water-containing tissue, skin vaporization occurs with production of coagulative necrosis in the remaining dermis. Tissue vaporization is best accomplished with minimal coagulation or residual thermal damage when exposure times are shorter than 1 millisecond. In addition, 5 J/cm2 of energy is needed to exceed the vaporization threshold of the targeted skin. Two different carbon dioxide laser technologies can deliver sufficient energy to vaporize the skin in less than 1 millisecond. One involves the use of an ultra-short pulse to deliver the energy to tissue. The second uses a computer-controlled optomechanical shutter system, which scans a continuous wave beam so rapidly that the emitted light is prevented from contacting skin for more than 1 millisecond. Several factors contribute to the fact that uniform laser parameters in clinical practice do not exist. While several clinical and histologic studies have been reported in the medical literature, varying styles of laser practice between surgeons could affect end clinical results. In addition to the laser parameters chosen, for example, clinical effect is also influenced by the number of laser passes delivered, the degree of pulse or scan overlap, the complete/incomplete removal of partially desiccated tissue between each laser pass, preoperative preparation, and postoperative wound care. INDICATIONS AND PATIENT SELECTIONSection 4 of 10
Indications As with any modality, the surgeon must have a complete understanding of the indications and limitations of a given procedure. The carbon dioxide laser is a powerful tool in the cosmetic surgeon's armamentarium that can have beneficial effects when used properly for the correct indication. Skin resurfacing with a pulsed or scanned carbon dioxide laser is largely used for improvement of fine or moderate rhytids. While deeper rhytids may also be improved, other procedures such as autologous fat transplantation, Contour Treadlifting, Sculptra injections, Gore-Tex/other implantation, or surgical lifting can be used to provide additional benefit. Dyschromias, including solar lentigines, are often improved with laser resurfacing, although they are not generally regarded as a primary indication for treatment. Improvement of melasma has been reported, although the recurrence rate after laser resurfacing is high. Carbon dioxide laser resurfacing may greatly improve atrophic scars caused by acne, trauma, or surgery. Deeper pitted acne scars often require ancillary procedures for optimal results, such as excision or punch grafting. These procedures can be performed either prior to or concomitant with carbon dioxide laser resurfacing. Other conditions that have been shown to respond favorably to carbon dioxide laser resurfacing include rhinophyma, severe cutaneous photodamage (observed in Favre-Racouchot), sebaceous hyperplasia, xanthelasma, syringomas, actinic cheilitis, and diffuse actinic keratoses. The carbon dioxide laser was used more often in the past for tattoo removal (in conjunction with dermabrasion and salabrasion); however, its use for this purpose has been largely abandoned because of the availability of more tattoo-specific lasers. Treatment areas The success of a cutaneous resurfacing procedure relies upon the presence of skin appendages (eg, sweat glands, folliculo-infundibular units) to serve as sources of epithelium that can migrate upward to form the new epidermis. Therefore, the greater the number of skin appendages per square centimeter of skin, the more rapid the healing and the less risk for scarring. For this reason, carbon dioxide laser resurfacing is largely limited to the face. Resurfacing of the hands and neck has been successful, although much greater risk for scarring exists when treating these areas. Patient selection As with any cosmetic procedure, proper patient selection is essential. During the initial consultation, the surgeon should ascertain the patient's expectations of treatment. Also, ascertain how the patient arrived at the decision to have cosmetic surgery. A complete medical and surgical history, including recent use of isotretinoin (its regular use within 6 months to a year of dermabrasion had shown higher risk of hypertrophic scarring), should be obtained. History of previous laser resurfacing, dermabrasion, or deep phenol peel is noteworthy because these procedures could potentially slow the wound healing response due to the presence of fibrosis. Patients with a prior history of transcutaneous lower blepharoplasty and limited infraorbital elasticity may have increased risk of ectropion. When applicable, patients should be discouraged from smoking before and after surgery to reduce the risk of delayed or impaired wound healing. A thorough examination of the skin to be treated should be performed, carefully noting scarring, dyschromia, rhytid formation, and skin type. For patients desiring periorbital laser treatment, a careful examination of the eyes for scleral show, lid lag, and ectropion should be performed. Other cutaneous disorders should also be investigated, including seborrheic keratosis, solar lentigines, actinic keratosis, acne vulgaris, and cutaneous carcinomas. The latter should be treated prior to any resurfacing procedures. With this information, the benefits of laser resurfacing must be assessed, along with its limitations, risks, and benefits. Perhaps most important, one must be certain that the patient has realistic expectations and sound reasons for deciding to undergo the cosmetic laser surgical procedure. Other cosmetic surgery treatments should be reviewed so that the patient may make an informed decision. CONTRAINDICATIONS AND CAUTIONSSection 5 of 10
Absolute contraindications include isotretinoin use within the previous 6 months, active cutaneous bacterial or viral infection in the area to be treated, and ectropion (for infraorbital resurfacing). Relative contraindications include patient history of keloid formation or hypertrophic scarring, ongoing ultraviolet exposure, prior radiation therapy to treatment area, and collagen vascular disease. Caution should be taken with patients who smoke or who have a history of previous laser resurfacing, phenol chemical peel, dermabrasion, and/or transcutaneous lower blepharoplasty. Also, patients planning to undergo neck or extremity laser resurfacing should be forewarned of the increased risk of fibrosis in these areas. ANTIVIRAL AGENTS AND ANTIBIOTICS: THEIR ROLES IN LASER RESURFACINGSection 6 of 10
Oral antiviral agents Because laser skin resurfacing can cause reactivation of latent herpes simplex infection or can predispose the patient to a primary infection during the reepithelialization phase of healing, surgeons are recommended to routinely prescribe the prophylactic use of an antiviral medication during the postoperative period, regardless of a patient's herpes simplex virus history. Some surgeons begin the regimen 24 h prior to surgery, while others initiate treatment on the morning of surgery. Commonly used regimens include famciclovir 250 mg PO bid, acyclovir 400 mg PO tid, and valacyclovir 500 mg PO bid for 7-10 d. Antibiotics Some surgeons routinely prescribe antibiotics for bacterial prophylaxis; however, little data exist to support their use, given the relatively low incidence of postoperative bacterial infection.1 When used, a cephalosporin (cephalexin), semisynthetic penicillin (dicloxacillin), macrolide (azithromycin), or quinolone (ciprofloxacin) is begun 1 day before or on the day of surgery and continued until reepithelialization is complete. The use of topical antibiotics on the laser-induced wound is not routinely recommended because of the possibility of contact dermatitis. ANESTHESIASection 7 of 10
For localized areas, local infiltration with 1% lidocaine with epinephrine or tumescent anesthesia using standard Klein solution is usually sufficient to produce adequate anesthesia. For larger areas, such as full-face resurfacing, nerve blocks (eg, supraorbital, supratrochlear, infraorbital, mental) are often used with local infiltration. Some surgeons use tumescent anesthesia with or without nerve blocks to provide local anesthesia, while others prefer to use conscious sedation (or twilight anesthesia) alone or in conjunction with other techniques. COMMONLY USED LASER PARAMETERS AND OTHER VARIABLESSection 8 of 10
While clinical and histologic studies using various laser parameters and different laser systems have been performed, no consensus has been reached regarding the optimal parameters to use in every clinical setting. Most surgeons use their experience and the experience of others as guidance in determining the parameters to use in each case. POSTOPERATIVE CARE AND COMPLICATIONSSection 9 of 10
Postoperative wound care Postoperative wound care varies considerably from surgeon to surgeon. Wounds reepithelialize more rapidly in a moist environment. Also, crust and eschar impede keratinocyte migration and retard the healing process. Therefore, most surgeons advocate maintaining a moist environment either with topical emollients and/or with semiocclusive dressings. Postoperative wound care can follow an open or closed method. With the closed method, a semiocclusive dressing (usually involving hydrogel) is placed on the denuded skin. These wound dressings have been shown to accelerate the rate of reepithelialization by maintaining a moist environment. In addition, decreased postoperative pain has been reported with their use. However, some believe that occlusive dressings also yield a low-oxygen environment that may promote the growth of anaerobic bacteria, thereby causing infection and impeding wound healing. As such, many proponents of the closed technique now combine the use of semiocclusive dressings with topical emollients. Others simply advocate the use of an open postoperative method, involving the application of copious amounts of topical emollients to promote rapid reepithelialization without risking prolonged occlusion and inability to observe the wound surface. Complications after laser resurfacing3 Carbon dioxide laser resurfacing imparts a thermal injury to denuded skin. Therefore, side effects are expected and must be differentiated from complications. Nearly all patients encounter side effects ranging from postoperative pain and edema to pruritus and tightness. Mild complications sometimes occur and usually are of minimal consequence. Minor complications include milia formation, perioral dermatitis, acne and/or rosacea exacerbation, contact dermatitis, and postinflammatory hyperpigmentation. Moderate complications include localized viral, bacterial, and candidal infection, delayed hypopigmentation, persistent erythema, and prolonged healing. The most severe complications are hypertrophic scarring, disseminated infection, and ectropion. Early detection of complications and rapid institution of appropriate therapy are extremely important. Delay in treatment can have severe deleterious consequences, including permanent scarring and dyspigmentation. REFERENCESSection 10 of 10
Cutaneous Laser Resurfacing: Carbon Dioxide excerpt Article Last Updated: Nov 13, 2007 |
