Analysis of hyperpigmentation and hypopigmentation after Er:YAG laser skin resurfacing

BACKGROUND AND OBJECTIVES: Pigmentary disorders--such as hyperpigmentation and hypopigmentation, are devastating complications of erbium:yttrium-aluminum-garnet (Er:YAG) laser resurfacing. This study was undertaken to assess the clinical and histopathologic features of hyperpigmentation and hypopigmentation following Er:YAG laser resurfacing, especially in darker skin. STUDY DESIGN/MATERIALS AND METHODS: One hundred and ninety patients (skin phototypes III and above), treated with Er:YAG lasers--short-pulsed and modulated (variable-pulsed and dual-mode) Er:YAG lasers--for skin resurfacing were recruited. The clinical features of hyperpigmentation and hypopigmentation were evaluated retrospectively using medical charts and serial photographs. For histopathologic examinations, skin biopsies were performed in three patients at hyperpigmentation sites and in four patients at hypopigmentation sites. RESULTS: Hyperpigmentation was observed in 38.4% of the patients. Mean onset and duration were 3.5 and 7.2 weeks, and then it has faded away within 16 weeks in 93.2% of cases. Hypopigmentation was observed in 13.7% of the patients; its mean onset was 2 months after treatment, and it faded within 1 year in 85% of cases. The incidences and mean durations of these side effects were more intense and longer in patients treated with short-pulsed, variable-pulsed, and dual-mode Er:YAG lasers, in increasing order. In terms of histopathologic examinations, melanin amounts in the epidermal basal layer were observed to vary. CONCLUSIONS: Hyperpigmentation and hypopigmentation are frequent complications of Er:YAG laser resurfacing. Long pulse duration-induced thermal damage seems to be the most important factor in terms of the induction of pigmentary disorders.     

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.     

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.     

Treatment of Facial Skin Using Combinations of CO2, Q-Switched Alexandrite, Flashlamp-Pumped Pulsed Dye, and Er:YAG Lasers in the Same Treatment Session

BACKGROUND: Many patients who seek facial CO2 laser resurfacing for improvement of photodamage are also concerned with "dark circles" under their eyes (periorbital hyperpigmentation) and/or telangiectasia as well as various types of deep scars on their faces. CO2 laser resurfacing alone provides limited improvement for these problems. OBJECTIVE: The purpose of this study was to demonstrate the conjunctive therapeutic effects of the CO2, Q-switched alexandrite, Er:YAG, and/or flashlamp-pumped pulsed dye lasers on facial skin treatments. METHOD: Thirty patients who underwent CO2 laser resurfacing were treated with additional lasers specific for their cosmetic concerns. Twenty patients with facial telangiectasias were treated with the pulsed dye laser immediately prior to CO2 laser resurfacing. Eleven patients with periorbital hyperpigmentation were treated with the Q-switched alexandrite laser immediately following use of the pulsed CO2 laser. Eight patients having sharply defined acne scars were treated with the Er:YAG laser following use of the CO2 laser. All patients had peripheral feathering performed with the Er:YAG laser. Nine patients were treated with all four lasers. RESULTS: In addition to significant improvement of the wrinkle scores from the CO2 laser resurfacing, patients had 75-100% clearing of the periorbital hyperpigmentation. All patients with facial telangiectasia showed virtually 100% improvement. All deep wrinkles and sharply defined scars responded with combined CO2/Er:YAG laser better than with CO2 laser resurfacing alone. All feathering was more uniform, with a more subtle transition to nontreated skin. There were no complications that could be attributed to the simultaneous use of multiple lasers. CONCLUSIONS: For patients who present with multiple cosmetic complaints, combined treatment using appropriate lasers offers excellent therapeutic outcome.     

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.     

Histologic Effect of a Variable Pulsed Er:YAG Laser

BACKGROUND: Carbon dioxide (CO2) lasers used for laser resurfacing produce significant thermal damage. Short-pulsed Er:YAG lasers provide significant control over depth of ablation with minimal thermal damage. Newer combined short-pulsed/long-pulsed Er:YAG lasers offer the potential for both precise control over depth of ablation and degree of chosen thermal damage. OBJECTIVE: To determine the correlation between the histologic effects of an ablative short-pulsed Er:YAG laser and/or a thermally damaging longer-pulsed Er:YAG laser and the findings chosen on the touch panel of such a machine. METHODS: In situ lasing of abdominoplasty specimens was undertaken. Various depths of ablation and/or thermal effect were chosen on the machine. The tissue was laser irradiated, histologically analyzed, and ablation/thermal depths of damage were analyzed by a blinded dermatopathologist. RESULTS: Postlaser histologic depths of ablation after short-pulsed Er:YAG laser resurfacing correlated well with those chosen on the machine. However, when a longer, thermally damaging Er:YAG laser pulse was chosen, chosen ablative and/or thermal depths of damage showed histologic correlation only for the first pass. With repeated passes, using the variable pulse width, the histologic depth of ablation and residual thermal damage do not match the settings on the machine. CONCLUSION: A dual-mode Er:YAG laser provides the histologic control over depth of ablation seen with all short-pulsed Er:YAG lasers. In addition, the histologic thermal effect desired from CO2 lasers could be observed when such a system is used with longer Er:YAG laser pulses. Good correlation between chosen laser parameters and histologic findings are seen with all chosen levels of short-pulsed Er:YAG laser parameters. Good correlation is seen between the chosen laser parameters and histologic findings after a first pass of either a longer pulsed thermal damaging Er:YAG laser alone or in combination with a shorter pulsed ablative Er:YAG laser. However, subsequent laser passes in these modes showed poor correlation between the chosen laser parameters and histologic effect. Such findings have important implications when such a laser is used clinically.     

Laser resurfacing with a long pulse erbium:YAG laser compared to the 950 ms pulsed CO(2) laser

BACKGROUND AND OBJECTIVE: Laser resurfacing with the 950 micros pulsed CO(2) laser is an effective treatment for photodamage and acne scarring; however, the potential for prolonged erythema and delayed re-epithelialization dissuade many patients from the procedure. With the use of erbium lasers alone, there is a decrease in the incidence and severity of these adverse sequelae; however, it is difficult to achieve the same degree of improvement as with the CO(2) laser because of the more superficial depth of resurfacing. Thus, new erbium lasers have been developed with longer pulse durations to deliver increased thermal effects to tissue. It is hypothesized that with the use of these lasers, diminished erythema and faster wound healing will be observed as well as enhanced clinical outcomes. STUDY DESIGN/MATERIALS AND METHODS: Sixteen patients were randomized to receive laser resurfacing on one-half of the face with the 950 micros pulsed CO(2) laser (UPCO(2)) followed by short pulse erbium:YAG ablation, and to the other half with a variable pulsed erbium laser (VP Er:YAG) followed by traditional short pulse erbium laser. Patients were evaluated clinically before resurfacing and at 1, 2, 4, 8, and 12 weeks post-operatively. Histologic samples taken at various time periods before and after resurfacing were also evaluated. RESULTS: Overall clinical improvement was equal for both UPCO(2) and VP Er:YAG treated sides with an average improvement in photoaging scores of 57%. Decreased erythema, less edema, and faster healing were observed on the VP Er:YAG treated side. CONCLUSION: The VP Er:YAG laser can achieve a similar degree of improvement as seen with short pulse CO(2) laser resurfacing with decreased thermal tissue effects and decreased risk for adverse sequelae.     

One-Pass CO2 Versus Multiple-Pass Er:YAG Laser Resurfacing in the Treatment of Rhytides: A Comparison Side-by-Side Study of Pulsed CO2 and Er:YAG Lasers

BACKGROUND: The CO2 laser is normally described as an aggressive resurfacing tool, whereas the erbium:YAG laser has enjoyed a reputation as the ideal tool for superficial resurfacing. The implication from many studies is that the CO2 laser is incapable of "minimally invasive" resurfacing. OBJECTIVE: To compare a short-pulsed CO2 laser with an Er:YAG laser over a range of parameters intended to produce equivalent microscopic and clinical injuries. METHODS: A prospective, randomized, comparative interventional trial was conducted in a tertiary care teaching hospital. Thirteen patients with facial wrinkles were enrolled in the study. A side-by-side comparison was performed using periorbital and perioral regions as treatment sites. One side was treated with a pulsed CO2 laser and the other with an Er:YAG laser. Postauricular skin was treated in an identical fashion to the study sites and biopsied for microscopic analysis. The biopsies were obtained before treatment, immediately after treatment, and either 3 or 6 months after treatment to evaluate the acute level of injury and subsequent degree of fibroplasia. Photographs were taken at baseline, immediately after treatment, 1, 2, and 6 weeks, and 3 and 6 months after treatment. Nine physicians evaluated the photographs for erythema, pigmentation, and wrinkle improvement. RESULTS: Investigator assessment showed no statistically significant differences between the lasers with respect to hyperpigmentation and wrinkle reduction. There was less erythema at the CO2 laser-treated sites 2 weeks after treatment; the differences had resolved by 6 weeks after treatment. Histologic examination demonstrated equivalent dermal thermal injury on immediate postoperative biopsies and equivalent fibroplasia on subsequent biopsies. Both CO2 and Er:YAG laser-treated sites showed overall modest wrinkle improvement compared to the pretreatment photographs. CONCLUSION: When CO2 and Er:YAG lasers are used in a manner such that there are equivalent immediate postoperative histologic results, equivalent healing and cosmetic improvement occurs. One can use CO2 laser with one pass to mimic a moderately aggressive Er:YAG laser treatment.     

Laser Resurfacing of the Neck with the Combined CO2/Er:YAG Laser

BACKGROUND: Several clinical studies on laser resurfacing on the neck have yielded variable results with adverse sequelae of hypopigmentation and scarring using the CO2 laser. The Er:YAG laser on the neck resulted in an improved appearance with no adverse sequelae. The combined CO2/Er:YAG laser is a laser that combines a low fluence CO2 laser with the Er:YAG laser in a near simultaneous beam. OBJECTIVE: To study the effects of the CO2/Er:YAG laser on the neck. The decreased nonspecific thermal damage of the CO2/Er:YAG laser should result in decreased postoperative erythema and improved wound healing. METHODS: Eleven patients were treated with the CO2/Er:YAG laser on the neck as well as the face at identical settings. The face was treated with four passes while the neck was treated with two passes. The patients were evaluated for the first 2 weeks then 3-6 months postoperatively. Patients were asked about treatment satisfaction and improvement in skin texture and color using a 25% scale. Skin texture and color, as well as improvement in wrinkling and adverse results were judged by a dermatologist using a 0-4 scale. RESULTS: Moderate improvement was seen in skin color while a higher degree of improvement was seen in skin texture and wrinkling in all 11 patients. No adverse sequelae, including hypopigmentation or scarring, were observed. The majority of patients had a 75-100% improvement in skin texture and color in addition to a 75-100% overall satisfaction rating. CONCLUSIONS: There is a higher degree of overall patient satisfaction, as well as improvement in skin texture and skin color, compared to patients treated with the Er:YAG laser alone. The CO2/Er:YAG laser is a highly effective laser for neck resurfacing with no adverse sequelae to date.     

Er:YAG Laser Resurfacing Using Combined Ablation and Coagulation Modes

BACKGROUND: The two main laser types used in resurfacing, the CO2 and the Er:YAG lasers, have their supporters and detractors, and each system has clear advantages and disadvantages. OBJECTIVE: The Er:YAG laser can be used in the usual efficient ablative mode, followed by reprogramming to achieve nonablative deeper dermal coagulation associated with the CO2 laser, thereby achieving the main advantages of both laser types. PATIENTS AND METHODS: Twenty-three female patients, ages 42-72 yrs, skin types I-IV, were treated. The epidermis was first removed in the ablative settings in a single pass with 50% overlap. The Er:YAG laser was reprogrammed for the subablative mode, and several passes produced controlled residual thermal damage (RTD) without further ablation. RESULTS: At 2 months postresurfacing the results were assessed. Thirteen patients were rated "very good," eight as "good," and two as "fair." CONCLUSION: The dual mode Er:YAG laser can first be used in the ablative mode to remove the epidermis with minimal RTD, following which, in the subablative mode, the same laser induces a controlled layer of dermal RTD, stimulating the dermis to achieve collagenesis and collagen remodeling and giving good long-term results.     

Carbon dioxide and ER:YAG laser resurfacing. Results

Laser resurfacing is exciting "futuristic" surgery. The CO2 laser resurfaces using different parameters from the Er:YAG laser. When the surgeon understands these parameters, each laser can be used as a powerful tool for specific clinical applications. The Er:YAG laser was initially thought to be for the patient who has minimal skin laxity, but who desires skin resurfacing and needs a speedy return to social life. The CO2 laser has typically been thought to work best for skin laxity as well as rhytids, at the price of a longer recovery period. As the hardware and techniques continue to evolve, the differences between the clinical scope addressed by each laser diminishes. Both lasers deserve a place in the plastic surgeon's armamentarium. This new combination CO2/Er:YAG technique is intriguing and deserves further in-depth investigation. Laser resurfacing is not a cureall, but, when applied appropriately, it is an excellent tool that the plastic surgeon can use for skin rejuvenation.     

Skin resurfacing with the erbium:YAG laser.

The Er:YAG laser provides superficial ablation and is generally used for more superficial rejuvenation. Three newer systems provide for thermal-coagulative and ablative properties. These systems are considered as intermediate resurfacing lasers, providing faster healing and results that are typically in between those of the CO2 and standard Er:YAG lasers. The use of traditional and combination Er:YAG lasers is reviewed along with preoperative and postoperative considerations.     

The Effects of Variable Pulse Width of Er:YAG Laser on Facial Skin

BACKGROUND: The use of CO2 and Er:YAG lasers for resurfacing has increased significantly in the past few years. Er:YAG laser causes pinpoint bleeding during and after treatment with a typical pulse width of 250 microsec. A longer pulse of Er:YAG laser can potentially coagulate dermal blood vessels and increase the residual thermal damage (RTD). OBJECTIVE: To evaluate the effects of various pulse durations of Er:YAG laser on the depth of RTD and bleeding. METHODS: The preauricular skin of a volunteer was exposed to Er:YAG laser at 250-, 350-, and 700-microsec pulse durations, with a fluence of 5 J/cm2. The number of passes varied between 6 and 16. The treated skin was excised and a histologic evaluation was done. RESULTS: The maximum depth of RTD was 50 microm and there was decreased bleeding with a 700-microsec pulse duration. CONCLUSION: The increased pulse duration of Er:YAG laser of 700 micros does not increase the maximum reported RTD and therefore would not change the recovery time and may have a beneficial effect on hemostasis.     

Combined Laser Resurfacing with the 950-μsec Pulsed CO2+ Er:YAG Lasers

INTRODUCTION: Laser resurfacing with the 950 microsec pulsed CO2 laser has been proven to be efficacious in improving photodamaged skin and acne scarring. Unfortunately, prolonged erythema and delayed wound healing are common adverse sequelae, which require intensive patient education and intervention. These adverse effects may be due to the degree of nonspecific thermal damage present after resurfacing with the CO2 laser. Since erbium: YAG (Er:YAG) laser vaporization leaves far less thermal damage, it is hypothesized that its use after CO2 laser resurfacing will decrease the extent of nonspecific damage and result in improved wound healing. METHODS: Ten patients were randomized to receive laser resurfacing of one-half of the face with the 950 Msec pulsed CO2 laser with 3 passes at 300 mJ, utilizing the computer pattern generator (CPG) at settings of 596, 595, 584, and the other half of the face (randomly chosen) resurfaced with the 950 Msec pulsed CO2 laser 2 passes with the CPG at 300 mJ at settings of 596 and 595, followed by 2 passes with the Er:YAG laser (Derma-20 or Derma-K, ESC Medical Systems, Inc., Needham, MA) with a 4 mm diameter spot size at 1.7 J (approximately 14 J/cm2). Patients were evaluated in a "blinded" manner clinically and histologically before resurfacing, immediately after resurfacing, 2 to 3 days postoperatively, 1 week postoperatively, and, 4 to 8 weeks postoperatively. RESULTS: There was slightly less inflammation with the CO2/Er:YAG-treated patients. The epidermis re-formed 1 to 2 days faster with combination (UPCO2)/Er:YAG treatment than with UPCO2 laser treatment alone. In 7 of 10 patients, Er:YAG erythema resolved within 2-3 weeks with CO2 x 3 erythema persisting at the 8-week follow-up period in all patients. Three of 10 patients had no difference in the degree of erythema between the 2 treatment areas. Clinical findings correlated with histologic findings of vascularity. There was no difference in the extent or time of edema between techniques. The usual demarcation line between cheek and neck at the mandibular angle was less apparent when the UPCO2/Er:YAG combination was used. Two of 10 patients noted quicker healing with the combination laser technique. CONCLUSION: Treating a patient with the Er:YAG laser after treatment with the UPCO2 laser results in a decreased incidence of adverse sequelae without a noticeable difference in the degree of wrinkle improvement.     

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.     

CO2 laser resurfacing of the face and neck.

Laser resurfacing with the short-pulsed, high-energy CO2 laser has been used to treat photodamaged skin and acne scars. Efficacy and safety have been demonstrated with this technique since 1992. Newer treatment methods, including sequential or combination treatment with the Er:YAG laser have led to increased efficacy with a decrease in adverse sequelae. This article details the author's experience with CO2 laser resurfacing and promotes the use of sequential CO2/Er:YAG laser resurfacing.     

Combined CO2/erbium:YAG laser resurfacing of peri-oral rhytides and side-by-side comparison with carbon dioxide laser alone.

BACKGROUND: Laser resurfacing of facial rhytids has become a popular treatment option for many patients with wrinkles, photoaging, and acne scarring. Laser wavelength options and optimization of techniques continue to evolve in an attempt to shorten the healing phase associated with laser skin resurfacing. OBJECTIVE: To prospectively study the clinical effects of pulsed carbon dioxide (CO2) laser resurfacing of facial rhytids used alone, compared with a combination of CO2 and the pulsed Erbium:YAG (Er:YAG) laser. METHODS: Forty treatment sites on 20 patients were randomized and evaluated following treatment of the upper lip region with a combination of CO2 laser resurfacing alone or with the same CO2 laser treatment followed by 3 passes with the Er:YAG laser. Patient diaries were maintained to assess erythema, crusting, pain, itching, swelling, pigmentary changes, and the day of first make-up application. Blinded objective grading of improvement was independently assessed by 4 blinded observers at time intervals 3, 6, and 10 days, and 1, 2, and 4 months. Chromometer measurements of erythema were also analyzed and percentage moisture recorded. RESULTS: Subjectively, all patients reported, on average, 10 days of redness and 2.4 days of pain, with no significant difference noted between the two procedures. On average, patients were able to apply make-up 5.5 days postoperatively, regardless of which procedure used. However, the combined CO2/Er:YAG laser treatment patients experienced reduced duration of crusting, compared to the patients treated with CO2 alone. The duration of crusting was reduced on average from 7.4 to 6.5 days, and also the duration of itching was reduced in patients receiving combined treatment from 5.5 to 4.8 days. Chromometer measurements noted no significant difference between techniques in the rate of resolution of erythema. Blinded objective grading revealed that crusting was reduced on average from 7.2 to 6.0 days, and swelling was reduced from 6.3 to 6.0 days in patients receiving the combined procedure. No cases of permanent hyperpigmentation, hypopigmentation, or scarring occurred in any patients. CONCLUSION: The addition of the Er:YAG laser following CO2 laser resurfacing reduces the duration of crusting, swelling, and itching postoperatively. Medium to deep (Grade III) facial rhytids were improved by 70% with both procedures with no significant difference noted between techniques.     

Analysis of Erythema after Er:YAG Laser Skin Resurfacing

BACKGROUND Postoperative erythema can be expected to occur in every patient after laser resurfacing, and pigmentary disturbances may be related to the intensity and the duration of erythema.
OBJECTIVE This study was undertaken to assess the clinical features of erythema, the factors that influence its duration, and the relation between the duration of erythema and the incidence of hyperpigmentation and hypopigmentation in skin of Asian persons after Er:YAG laser resurfacing.
METHODS A total of 218 patients (skin phototypes III to V) were recruited and treated with a short-pulsed Er:YAG laser, a variable-pulsed Er:YAG laser, or a dual-mode Er:YAG laser for skin resurfacing. Clinical assessments were performed retrospectively using medical charts and serial photographs.
RESULTS Postoperative erythema was observed in all patients after Er:YAG laser resurfacing with a mean duration of 4.72 months. In 98.2% of patients, erythema faded completely within 12 months. Postinflammatory hyperpigmentation was observed in 38.1% of patients after Er:YAG laser resurfacing.
CONCLUSIONS Skin phototype, level of ablation, and depth of thermal damage caused by a long-pulsed laser appear to be important factors that affect the duration of erythema. Moreover, prolonged erythema was related to the risk of postinflammatory hyperpigmentation.     

Effect of Laser Resurfacing on p53 Expression in Photoaged Facial Skin

BACKGROUND: p53 overexpression has been reported in photoaged skin. Meanwhile, p53 gene mutations have been implicated as an important factor in the pathogenesis of ultraviolet (UV) light-induced skin cancer. OBJECTIVE: The objective was to evaluate the effect of laser resurfacing on the epidermal thickness and expression of p53 in photoaged skin. METHODS: Specimens were obtained from the facial skin of 10 patients before and after 3 months and 1 year of treatment using CO(2) (five cases) and erbium (Er):YAG (five cases) lasers. Specimens were also obtained from six age-matched controls. These biopsies were used for routine histopathology, histometry, and p53 immunoperoxidase staining. RESULTS: Both CO(2) and Er:YAG lasers were found to induce a significant decrease in p53 expression in biopsies obtained after 3 months (p=.0004 and .002, respectively) followed by gradual increase (p=.01 in both groups). A significant increase (p<.01) in epidermal thickness was also observed after 1 year of resurfacing. This increase, however, is inversely correlated with the level of p53 expression in such patients. CONCLUSION: The decrease in epidermal p53 expression after CO(2) and Er:YAG lasers may account for some of the benefits of resurfacing on the epidermis, as well as prevention of actinic neoplasia by adjusting any disturbance in the proliferation/apoptosis balance observed in photoaged facial skin.     

Laser skin resurfacing using a frequency doubled Nd:YAG laser after topical application of an exogenous chromophore.

BACKGROUND AND OBJECTIVES: Although laser skin resurfacing performed with CO(2) or Er:YAG lasers is efficient, side effects such as prolonged postoperative erythema, delayed healing, scarring, and pigmentation, have been reported. These side effects are due to skin characteristics but also to variations of the thermal effects associated with laser skin resurfacing. The study aimed to evaluate a new laser resurfacing method based on a previous topical application of an exogenous chromophore in order to have reproducible thermal effects. MATERIALS AND METHODS: Exogenous chromophore consisted in carbon dispersed and mixed with film-forming polymers and water. The resultant solution was applied to the skin surface using an airbrush. Experimental evaluation was performed in vivo on hairless rat skin using the following parameters (532 nm, 2.7 W, 1 mm, 50-200 ms, 17.2-68.8 J/cm(2), single pass). Skin biopsies were taken to evaluate histological changes and to quantify epidermis ablation and dermal coagulation depth. Wound healing was followed up during 10 days. RESULTS: Total epidermis ablation was achieved with all pulse durations used. Dermal coagulation depth increased as a function of exposure time. Scar formation was correlated with dermal coagulation depth. CONCLUSION: The concept of applying a carbon-based solution onto skin in order to obtain laser light conversion into heat followed by heat transfer to the tissue is valid for laser skin resurfacing. By selecting exposure time, the thermal effects are predictable and dermal coagulation depth can be either that observed with a Er:YAG laser or that obtained with a CO(2) laser. Moreover, frequency doubled Nd:YAG laser, already used in dermatology for angiodysplasias treatment, could be easily used for resurfacing of periorbital or perioral zones.