Er:YAG Laser for the Treatment of Actinic Keratoses

BACKGROUND: There is no single optimal treatment for multiple facial actinic keratoses. The existing therapies such as topical 5-fluorouracil, chemical peels, cryotherapy, dermabrasion, and CO2 laser resurfacing can produce prolonged recovery time or are often operator dependent. OBJECTIVE: The purpose of this study was to investigate another therapeutic modality which provides a shorter recovery time with uniform results. We performed a prospective pilot study investigating the use of the Er:YAG laser for the treatment of multiple facial actinic keratoses. METHODS: Five patients with multiple facial actinic keratoses were treated with two to three passes of Er:YAG laser. Anesthesia was achieved in all cases by topical application and local infiltration when indicated. All patients were treated with 2.0 J, 5 mm spot size, and a fluence of 10 J/cm2. Clinical and histologic evaluations were performed both pre- and postoperatively. RESULTS: All patients showed a decrease in the total number of clinical actinic keratoses on the face ranging from 86 to 96%. In addition to the reversal of actinic damage in the epidermis, histologic evidence revealed increased fibroplasia and decreased superficial solar elastosis 3 months after the laser resurfacing. Reepithelialization occurred in 5-8 days, and erythema lasted for about 3-6 weeks after the procedure. There was no evidence of scarring or pigmentary changes in any of the patients during the follow-up period. CONCLUSION: Er:YAG laser skin resurfacing is a safe and effective treatment for multiple facial actinic keratoses. Histologic data suggest a new zone of collagen deposition occurs in the superficial papillary dermis. Under our current parameters, Er:YAG laser skin resurfacing has a relatively short recovery period and a low risk of scarring. Unlike the CO2 laser, Er:YAG laser skin resurfacing can be performed with topical anesthesia alone.     

Er:YAG Laser Treatment of Verrucous Epidermal Nevi

BACKGROUND: The term verrucous epidermal nevi refers to benign hyperplasia of the epidermis. Numerous treatment modalities have been tried, but no ideal treatment is yet available. We would like to present our experience with Er:YAG laser ablation in the treatment of verrucous epidermal nevi. OBJECTIVE: The purpose of this study is to assess the long-term results of Er:YAG laser treatment of verrucous epidermal nevi. METHODS: Twenty patients with verrucous epidermal nevi were treated with Er:YAG laser. Twelve patients were treated with the variable-pulsed Er:YAG laser, a 5-mm handpiece at the setting of 7.0 to 7.5 J/cm2, at a 500-micros pulse duration. The dual-mode Er:YAG laser, with a 2-mm handpiece at the setting of 6.3 J/cm2, at a 350-micros pulse duration (25 microns ablation), was used in eight patients. The laser was fired at 5 Hz until all epidermal nevi were removed. The results of treatment were evaluated for the changes of skin lesions, texture, and color by physicians over a 24-month period. RESULTS: After a single laser treatment, successful elimination of the verrucous epidermal nevi was observed in 15 patients. Five patients (25%) showed a relapse within 1 year after the treatment. Postoperative healing time was 7 to 10 days. Erythema occurred in all patients after the laser treatment and subsided in 2 months. Postinflammatory hyperpigmentation occurred in two patients (10%). One patient (5%) experienced transient hypopigmentation. Mild to moderate postoperative acne flare-up occurred in one patient (5%) with facial lesions. No other adverse effects, including scarring, were observed. CONCLUSION: The Er:YAG laser ablation is an effective, safe, and nonscarring method for the treatment of verrucous epidermal nevi.     

Current lasers in skin resurfacing

Because of its cosmetic implications in the treatment of photoaging and facial rejuvenation, CO2 and Er:YAG laser resurfacing has raised a lot of interest. It has replaced dermabrasion and medium and deep chemical peels in many clinical settings. The best technique or combination of techniques for any given treatment will depend on the judgment and experience of the skilled clinician. Treatment results have been impressive. As laser technology is refined, the side effect and complication profiles of laser resurfacing continue to improve.     

Treatment of Atrophic Facial Scars with Combined Use of High-Energy Pulsed CO2 Laser and Er:YAG Laser: A Practical Guide of the Laser Techniques for the Er:YAG Laser

BACKGROUND: Although CO2 laser resurfacing provides substantial clinical improvement for atrophic facial scars, the CO2 laser often results in excessive thermal damage to the skin. It increases complications postoperatively. The Er:YAG laser ablates thinner layers of tissue than the CO2 laser with minimal thermal damage to the surrounding skin. OBJECTIVE: To determine the efficacy of combined treatment of atrophic facial scars with high-energy pulsed CO2 laser and Er:YAG laser. METHODS: One hundred fifty-eight patients were treated with a combination of high-energy pulsed CO2 laser and Er:YAG laser for atrophic facial scars. All patients were evaluated after 3 months of treatment. RESULTS: The scars improved 80-89% in 65 patients, 70-79% in 56 patients, more than 90% in 32 patients, 60-69% in 2 patients, and less than 60% in 3 patients after laser treatment. CONCLUSION: Treatment of atrophic facial scars with combined use of high-energy pulsed CO2 laser and Er:YAG laser is a very effective and useful method.     

Resurfacing of Pitted Facial Acne Scars with a Long-Pulsed Er:YAG Laser

BACKGROUND: Conventional short-pulsed Er:YAG lasers show less effective hemostasis and weak photothermal damage on papillary dermis. Recently, newer long-pulsed Er:YAG laser systems has been developed. OBJECTIVE: To evaluate the clinical and histologic effects of long-pulsed Er:YAG laser resurfacing for pitted facial acne scars. METHODS: Thirty-five patients with pitted facial acne scars were treated with a long-pulsed Er:YAG laser. All patients had Fitzpatrick skin phototypes III-V. A pulsed Er:YAG laser with a 5 mm handpiece at a setting of 7.0-7.5 J/cm2 with a 10-msec pulse duration was used. The laser was fired at 5 Hz, with four to five passes. In 28 patients, the results of laser treatment were evaluated for the degree of clinical improvement, duration of erythema, pigmentary change, and any adverse events at 2 weeks, 1 month, and 3 months. In seven patients, skin biopsy specimens were obtained at the following intervals: immediately, 1 week, 2 weeks, 4 weeks, and 8 weeks postoperatively for histologic examination. RESULTS: The results of long-pulsed Er:YAG laser resurfacing for pitted facial acne scars were excellent in 10 patients (36%), good in 16 patients (57%), and fair in 2 patients (7%). Erythema occurred in all patients after laser treatment and lasted longer than 3 months in 15 patients (54%). Postinflammatory hyperpigmentation occurred in 8 patients (29%). But the pigmentation faded or disappeared within 3 months. One patient (4%) experienced mild hypopigmentation. Pruritic symptoms that required medical intervention occurred in 16 patients (57%). Mild to moderate postoperative acne flare-up occurred in 8 patients (29%). No other adverse effects such as scarring, bacterial infection, or contact dermatitis were observed. CONCLUSION: In conclusion, resurfacing with a long-pulsed Er:YAG laser is a safe and very effective treatment modality for pitted facial acne scars.     

Treatment of Atrophic Facial Acne Scars with a Dual-Mode Er:YAG Laser

BACKGROUND: Scar revision with CO2 and Er:YAG lasers has become popular in recent years. Reports on the newest (modulated, dual-mode) Er:YAG systems have been limited mostly to the treatment of photodamaged skin and rhytides. OBJECTIVE: To prospectively evaluate the efficacy and safety of a dual-mode 2940 nm Er:YAG laser for atrophic scar revision. METHODS: Twenty-five consecutive patients with moderate to severe atrophic facial acne scars received treatment with a dual-mode Er:YAG laser. Clinical assessments using a standard grading scale and photographic documentation were performed at 1, 3, 6, and 12 months postoperatively. Postoperative recovery was monitored and the rate of side effects and complications recorded. RESULTS: Average clinical grading scores reflected good to excellent response of atrophic scars to the dual-mode Er:YAG laser system. Side effects and complications were limited to transient hyperpigmentation and acne flare-ups. No hypopigmentation or scarring was seen. Prolonged erythema (longer than 1 month) was observed in 1 patient (4%). CONCLUSION: Dual-mode Er:YAG laser skin resurfacing is a safe and effective modality for the treatment of atrophic facial scarring.     

铒激光微剥脱治疗脂溢性角化病63例疗效观察

目的:观察铒激光微剥脱治疗脂溢性角化病的临床疗效。方法:采用铒激光微剥脱治疗脂溢性角化病63例,210个皮损,根据皮损的部位、性质及对激光的反应,选择能量10～12.5J/cm2治疗。结果:63例患者,共计210个皮损,治疗8周后随访,176个皮损痊愈,治愈率83.80%,34个皮损显效,有效率100%,未出现创面感染和瘢痕形成。结论:铒激光微剥脱治疗脂溢性角化病有效且安全。     

Early Recurrence of Eruptive Vellus Hair Cysts after Er:YAG Laser Therapy: Case Report and Review of the Literature

BACKGROUND: Therapy of eruptive vellus hair cysts (EVHCs) often leads to unsatisfying results or recurrences. Recently, erbium:yttrium-aluminum-garnet (Er:YAG) laser therapy has been recommended in this condition. OBJECTIVE: To report the results of Er:YAG laser treatment and discuss the treatment options in EVHC, presenting a review of the literature. METHODS: Full-face Er:YAG laser therapy was performed in a 30-year-old female patient with a 15-year history of cosmetically bothersome facial EVHCs. RESULTS: Immediately after the laser treatment, the ablated skin showed an even surface, presenting no residual signs of EVHCs. After reepithelialization, however, early recurrence of EVHCs occurred. Recurrence was also observed in the previously treated test spot, where slight atrophy indicated deeper ablation. CONCLUSION: Er:YAG laser therapy might be a treatment option for distinct lesions of EVHCs but proved to be ineffective in a case of EVHCs in the face, where the depth of ablation is limited owing to the risk of atrophy or scarring and where deep enucleation of distinct single cysts was not possible owing to the dense dissemination of the lesions. Despite numerous treatment options reported in the literature, therapy for EVHCs is still challenging owing to recurrences or side effects.     

Ablative Techniques in Psoriasis Vulgaris Resistant to Conventional Therapies

BACKGROUND: Treatment of patients with psoriasis vulgaris exhibiting only solitary plaque-stage lesions might become difficult since topical treatments often fail and systemic therapies seem inappropriate. OBJECTIVE: We evaluated the feasibility of ablative techniques in this clinical setting comparing dermatome shaving to the application of an Er:YAG laser. METHODS: Six patients were treated by means of dermatome shaving; in four of these patients additional lesions were ablated utilizing an Er:YAG laser (2 J, 10 Hz, 5 mm spot size). RESULTS: Four of six patients experienced complete clearance of the lesions treated, three of the four patients receiving additional Er:YAG treatment also showed a complete clinical response. CONCLUSION: Our observations document that removal of epidermis and the papillary dermis is effective in treating recalcitrant psoriatic plaques. The Er:YAG laser represents a state-of-the-art device for performing this task. The beneficial effect on skin might be due to clearance of the putative autoantigen along with a considerable part of the potential effector cell population.     

Resurfacing of Pitted Facial Acne Scars Using Er:YAG Laser with Ablation and Coagulation Mode

Although the conventional, short-pulsed erbium: yttrium-aluminum-garnet (Er:YAG) laser provides substantial clinical improvement for pitted, facial acne scars, it shows less effective hemostasis and limited residual thermal effect in the dermis. Recently, dual-mode Er:YAG laser systems with both ablation and coagulation modes have been developed. The purpose of this study was to evaluate the clinical and histologic effects of resurfacing pitted, facial acne scars with a dual-mode Er:YAG laser. Twenty patients with pitted facial acne scars underwent laser resurfacing using a computerized-scanning, dual-mode Er:YAG laser. All patients had Fitzpatrick skin types ranging III–V. Initially, the epidermis was removed in two passes using the ablative settings. This step was followed by two passes in a mixed ablation and coagulation mode, to produce further ablation and controlled, residual thermal damage. A final pass in a ablation mode was used to remove necrotic tissue. Laser overlapping was approximately 30%. The results of laser treatment were evaluated for the degree of clinical improvement, duration of erythema, pigmentary change, and any adverse events at two weeks, one month, and three months. In two patients, skin biopsies were obtained at the following intervals: immediately and two weeks postoperatively for histologic examination. There was a 75% average clinical improvement observed in pitted, facial acne scars after laser treatment. Complete wound healing occurred between six and eight days. On histologic examination, complete re-epithelialization was observed at two weeks. Erythema occurred in all patients after laser treatment and lasted longer than three months in 10 patients (50%). Post-inflammatory hyperpigmentation occurred in 12 patients (60%) two to four weeks after laser treatment and lasted longer than three months in one patient (5%). One patient (5%) experienced mild hypopigmention. Mild to moderate, postoperative acne flare-up occurred in seven patients (35%). No other adverse effects were observed. In conclusion, resurfacing with a dual-mode Er:YAG laser is a safe and effective treatment modality for pitted, facial acne scars.     

Treatment of Multiple Eruptive Hair Cysts with Erbium:YAG Laser

BACKGROUND: Eruptive vellus hair cysts (EVHC) frequently resist a variety of treatment modalities. While pulsed carbon dioxide (CO2) laser has been used effectively for facial EVHC, this laser presents significant risks for hypertrophic scarring when used on truncal sites. Due to absorption of 2940 nm energy by both tissue water and protein, the erbium:yttrium-aluminum-garnet (Er:YAG) laser ablates more cleanly and creates less residual thermal injury in the wound bed. This laser might prove efficacious and safe in treating nonfacial EVHC. OBJECTIVE: To assess treatment efficacy and wound healing after Er:YAG laser ablation of EVHC. METHODS: Two patients with 32 truncal EVHC were treated with pulsed Er:YAG laser using a drilling technique followed by second intention healing. RESULTS: Laser treatment sites healed without permanent dyspigmentation or hypertrophic scarring. No lesion recurrence was observed. CONCLUSION: Er:YAG laser ablation is an effective method for treating EVHC at anatomic sites prone to hypertrophic scar formation.     

Comparative Treatment of Giant Congenital Melanocytic Nevi with Curettage or Er:YAG Laser Ablation Alone versus with Cultured Epithelial Autografts

BACKGROUND: Treatment options for congenital melanocytic nevi (CMN) include complete surgical excision, dermabrasion, curettage, and laser therapy. Fresh cultured epithelial autograft (CEA) after curettage or erbium:yttrium-aluminum-garnet (Er:YAG) ablation presents a novel option in the management of large-sized or giant CMN. OBJECTIVE: The purpose of this study was to evaluate the outcome of CEA after curettage or Er:YAG ablation of CMN and to compare the safety, efficacy, and side-effect profile of CEA with the non-CEA group. METHODS: Ten patients with CMN were treated with curettage (one patient), Er:YAG ablation (four patients), or both (five patients) followed by CEA, and eight patients were treated with curettage (two patients), Er:YAG ablation (one patient), or both (five patients) without CEA. All 18 patients were evaluated at week 16 after the operation with respect to pigmentation, erythema, hypertrophic scarring, textural change, granulation tissue formation, infection, and healing time. Global Assessment Scale scores were graded before and 16 weeks after the operation by physicians and patients. RESULTS: Reduced pigmentation in the treated areas was seen in both groups, but the time to complete healing was significantly shorter in the CEA than in the non-CEA group (p < .05). There was less hypertrophic scar formation and granulation tissue formation and fewer other side effects in the CEA group. CONCLUSION: In view of the favorable outcome of CEA combined with curettage or Er:YAG laser ablation in the treatment of giant CMN, CEA is a safe and effective novel treatment adjunct that accelerates healing, with fewer side effects.     

Immediate Postoperative Laser Resurfacing Improves Second Intention Healing on the Nose: 5-Year Experience

BACKGROUND: Mohs surgery defects on convex nasal surfaces do not reliably heal well by second intention. Prior to the availability of laser resurfacing we found that immediate postoperative dermabrasion improved the predicted outcome from second intention healing for these defects. OBJECTIVE: To determine the ability of immediate postoperative CO2 and Er:YAG laser resurfacing to improve predicted healing by second intention. METHODS: Seventy-four patients with Mohs surgical defects on the nose underwent immediate postoperative resurfacing with either a scanned CO2 or long-pulsed Er:YAG laser. Thirty patients had photographs of appropriate quality and follow-up for evaluation by a panel of nine objective physicians. RESULTS: All 74 patients were satisfied with their result and none have requested scar revision. Of the 30 patients evaluated by the panel, all were scored acceptable to excellent. CONCLUSION: Immediate laser resurfacing can improve the predicted outcome from second intention healing on the nose and should be considered for select patients.     

Atrophic Facial Scars Secondary to Discoid Lupus Erythematous: Treatment Using the Erbium:YAG Laser

BACKGROUND: Discoid lupus erythematosus (DLE) is a chronic inflammatory skin condition notorious for causing disfiguring scars and alopecia. We describe the case of a 66-year-old woman with a 25-year history of relapsing DLE who developed extensive cribriform scarring on her face. OBJECTIVE: To assess the safety and efficacy of laser resurfacing in the treatment of facial scars in DLE. METHODS: One patient was treated with an Er:YAG laser and followed for more than 2 years. RESULTS: The patient showed remarkable cosmetic improvement with no hypertrophic scarring and no reactivation of her disease. CONCLUSION: Er:YAG laser resurfacing may be safe and effective in the treatment of patients with DLE-induced atrophic scars.     

Erbium:YAG laser treatment of post-burn scars: potentials and limitations

Erbium:YAG lasers are successfully used to treat a variety of epidermal and dermal lesions, including rhytides, dyschromias, and certain types of scars. To date, however, no report has focused on the experiences with this laser in reconstructive burn surgery. Since 2001, the Erbium:YAG laser has become an integral part of the treatment of postburn scars at the Berlin Burn Center. This paper presents the techniques applied and clinical experiences obtained. In addition, a new stripe technique is introduced, which avoids healing disturbances in scars following deep burns. In conclusion, the Erbium:YAG laser has proven to be a valuable supplementary tool for the improvement of cosmetically disturbing mild postburn scars. It is particularly handy in areas difficult to treat, such as the eyes, nose, lips, and fingers. The individual advantages of the Erbium:YAG laser, other laser systems, and dermabrasion for the treatment of burn scars are compared in a brief survey.     

Potential applications of the erbium:YAG laser in endourology.

The holmium:YAG laser has become the laser of choice in endourology because of its multiple applications in the fragmentation of kidney stones, incision of strictures, and coagulation of tumors. This paper describes the potential use of a new laser, the erbium:YAG laser, for applications in endourology. Recent studies suggest that the Er:YAG laser may be superior to the Ho:YAG laser for precise ablation of strictures with minimal peripheral thermal damage and for more efficient laser lithotripsy. The Er:YAG laser cuts urethral and ureteral tissues more precisely than does the Ho:YAG laser, leaving a residual peripheral thermal damage zone of 30 +/- 10 microm compared with 290 +/- 30 microm for the Ho:YAG laser. This result may be important in the treatment of strictures, where residual thermal damage may induce scarring and result in stricture recurrence. The Er:YAG laser may represent an alternative to the cold knife and Ho:YAG laser in applications where minimal mechanical and thermal insult to tissue is required.     

Pulsed Er:YAG- and 308 nm UV-excimer laser: an in vitro and in vivo study of skin-ablative effects

Using a pulsed XeCl excimer laser (308 nm) and a pulsed Er:YAG laser (2,940 nm), we investigated skin ablation as a function of pulse number, radiant energy, and repetition rate. In vitro analysis of lesions performed in freshly excised human skin were consistent with in vivo results obtained from experiments on pig skin. Pulsed 308 nm laser radiation caused considerable nonspecific thermal tissue injury followed by an inflammatory reaction and impaired healing of lesions in vivo. These findings were especially pronounced with higher repetition rates, which would be required for efficient destruction of larger lesions. On the other hand, the 2.94 microns Er:YAG laser radiation produced clean and precise lesions with only minimal adjacent injury. In vivo skin ablation caused intraoperative bleeding with deeper penetration. The Er:YAG laser offers a promising surgical tool for careful removal of superficial epidermal lesions, if higher repetition rates, and an appropriate laser beam delivery system are available for clinical use.     

Single-Pass Carbon Dioxide Versus Multiple-Pass Er:YAG Laser Skin Resurfacing: A Comparison of Postoperative Wound Healing and Side-Effect Rates

BACKGROUND: Ablative laser skin resurfacing with carbon dioxide (CO2) and erbium:yttrium-aluminum-garnet (Er:YAG) lasers has been popularized in recent years and their side effects individually reported. No prior study, however, has directly compared the relative healing times and complications rates between the two different systems. OBJECTIVE: To evaluate and compare postoperative wound healing and short- and long-term side effects of single-pass CO2 and multiple-pass, long-pulsed Er:YAG laser skin resurfacing for the treatment of facial photodamage and atrophic scars. METHODS: A retrospective chart review and analysis of sequential clinical photographs were performed in 100 consecutive patients who underwent laser skin resurfacing with single-pass CO2 (Ultrapulse 5000; Coherent, Palo Alto, CA, N=50) or multiple-pass, long-pulsed Er:YAG laser resurfacing (Contour; Sciton, Palo Alto, CA, N=50). All laser procedures were performed by a single operator for the amelioration of facial rhytides or atrophic scars. The rate of re-epithelialization, duration of erythema, and presence of complications were tabulated. RESULTS: The average time to re-epithelialization was 5.5 days with single-pass CO2 and 5.1 days with long-pulsed Er:YAG laser resurfacing. Postoperative erythema was observed in all patients, lasting an average of 4.5 weeks after single-pass CO2 laser treatment and 3.6 weeks after long-pulsed Er:YAG laser treatment. Hyperpigmentation was seen in 46% of the patients treated with single-pass CO2 and 42% of the patients treated with the long-pulsed Er:YAG laser (average duration of 12.7 and 11.4 weeks, respectively). No incidences of hypopigmentation or scarring were observed. CONCLUSION: Skin resurfacing with single-pass CO2 or multiple-pass long-pulsed Er:YAG laser techniques yielded comparable postoperative healing times and complication profiles.     

Erbium:YAG Laser Pretreatment Accelerates the Response of Bowen''s Disease Treated by Topical 5-Fluorouracil

BACKGROUND: Topical 5-fluorouracil (5-FU) is a standard treatment for Bowen's disease. However, its efficacy may be limited by the presence of stratum corneum. The Er:YAG laser has shown a dramatic enhancement effect on the delivery of 5-FU in vitro by ablation of the stratum corneum. The efficacy of laser-assisted delivery of 5-FU has not been tested in human. OBJECTIVE: To see whether Er:YAG laser pretreatment can improve the efficacy of topical 5-FU in the treatment of Bowen's disease. METHODS: Three target lesions from a patient with multiple Bowen's disease were selected for a half-side comparison study. The Er:YAG laser was used to remove the cornified layer on one side of each lesion, followed by twice-daily application of 5-FU cream to both sides. Clinical and histologic responses were compared. RESULTS: Lesions pretreated with the Er:YAG laser showed more rapid clinical and histologic responses to topical 5-FU than those treated with 5-FU alone. Evaluation at 9 months after treatment showed no recurrences of lesions on both sides. CONCLUSIONS: Our preliminary study demonstrates that this Er:YAG laser-assisted modality is effective and shows accelerated clinical response and shortened treatment time compared with topical 5-FU as a single treatment.     

Variable pulse erbium:YAG laser skin resurfacing of perioral rhytides and side-by-side comparison with carbon dioxide laser

BACKGROUND AND OBJECTIVE: Laser resurfacing of facial rhytides has become a popular treatment option for many patients with wrinkles, photoaging, and acne scarring. Laser wavelength/pulse duration options and new techniques continue to shorten the healing phase associated with laser skin resurfacing while maintaining clinical efficacy. Variable pulse erbium:YAG (Er:YAG) laser systems are now available that offer the surgeon the ability to vary the Er:YAG pulse duration from a pulse that is primarily ablative to one that is more thermal. The objective of this study was to evaluate the histologic effects created with a variable pulse Er:YAG laser. To study prospectively the clinical effects on upper lip rhytides with a variable pulse Er:YAG laser when compared side by side with pulsed carbon dioxide (CO(2)) laser resurfacing. STUDY DESIGN/MATERIALS AND METHODS: Forty-two treatment sites on 21 patients were randomized and evaluated after treatment of the upper lip region with CO(2) laser resurfacing on one side and a variable pulse Er:YAG laser on the other. Patient diaries were maintained to assess erythema, crusting, pain, and pigmentary changes. Blinded objective grading of improvement was performed. Chromometer measurements were obtained to analyze erythema. RESULTS: The variable pulse Er:YAG laser treatment reduced the duration of crusting on average from 7.7 days with CO(2) to 3.4 days. Chromometer measurements noted decreased postoperative erythema. Grading by physicians in a blinded manner showed 63% improvement for the CO(2) treatment site and 48% improvement in the variable pulse Er:YAG site. No cases of permanent hyperpigmentation, hypopigmentation, or scarring occurred. CONCLUSION: The variable pulse Er:YAG laser resurfacing is a safe and effective resurfacing tool, which combines ablative and thermal modalities. The protocol used in this study approaches but does not equal the results we have traditionally seen with CO(2) laser resurfacing.