YAG Laser (yag + laser)

Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by YAG Laser

  • yag laser irradiation
  • yag laser radiation
  • yag laser treatment

  • Selected Abstracts


    Comparison of a Long-Pulse Nd:YAG Laser and a Combined 585/1,064-nm Laser for the Treatment of Acne Scars: A Randomized Split-Face Clinical Study

    DERMATOLOGIC SURGERY, Issue 11 2009
    SEONG UK MIN MD
    BACKGROUND Nonablative laser is gaining popularity because of the low risk of complications, especially in patients with darker skin. OBJECTIVE To compare the efficacy and safety of a long-pulse neodymium-doped yttrium aluminium garnet (Nd:YAG) laser and a combined 585/1,064-nm laser for the treatment of acne scars. MATERIALS AND METHODS Nineteen patients with mild to moderate atrophic acne scars received four long-pulse Nd:YAG laser or combined 585/1,064-nm laser treatment sessions at fortnightly intervals. Treatments were administered randomly in a split-face manner. RESULTS Acne scars showed mild to moderate improvement, with significant Echelle d'évaluation clinique des cicatrices d'acné (ECCA) score reductions, after both treatments. Although intermodality differences were not significant, combined 585/1,064-nm laser was more effective for deep boxcar scars. In patients with combined 585/1,064-nm laser-treated sides that improved more than long-pulse Nd:YAG laser-treated sides, ECCA scores were significantly lower for combined 585/1,064-nm laser treatment. Histologic evaluations revealed significantly greater collagen deposition, although there was no significant difference between the two modalities. Patient satisfaction scores concurred with physicians' evaluations. CONCLUSION Both lasers ameliorated acne scarring with minimal downtime. In light of this finding, optimal outcomes might be achieved when laser treatment types are chosen after considering individual scar type and response. [source]


    Nonablative Acne Scar Reduction after a Series of Treatments with a Short-Pulsed 1,064-nm Neodymium:YAG Laser

    DERMATOLOGIC SURGERY, Issue 8 2006
    GRAEME M. LIPPER MD
    BACKGROUND Effective treatment of facial acne scarring presents a major challenge. Nonablative lasers and radiofrequency devices work by thermally stimulating dermal collagen remodeling, thereby softening acne scars in a minimally invasive fashion. One such laser, a 1,064-nm short-pulsed Nd:YAG, uses rapidly scanned low-energy infrared pulses to heat the dermis selectively through the normal dermal microvasculature. OBJECTIVE In this pilot study, the safety and efficacy of a novel short-pulsed Nd:YAG laser were investigated for the treatment of moderate to severe facial acne scarring. MATERIALS AND METHODS Nine of 10 enrolled patients with moderate to severe facial acne scarring received eight sequential 1,064-nm Nd:YAG treatments (laser parameters 14 J/cm2, 0.3 milliseconds, 5-mm spot size, 7-Hz pulse rate, 2,000 pulses per side of face). Patients were graded for the presence and severity of three scar morphologies: superficial (rolling), medium-depth (boxcar), and deep (ice pick). Outcome measures included blinded evaluation of before and after photographs by three physician observers (scar severity score) and patient self-assessment. RESULTS Acne scarring improved in 100% of the nine patients completing the study. Scar severity scores improved by a mean of 29.36% (95% confidence interval, 16.93%,41.79%; p=.006); 89% of patients noted greater than 10% scar improvement. No treatment-related adverse events were seen. CONCLUSION Our findings support the use of a short-pulsed, low-fluence 1,064-nm Nd:YAG laser as a safe, effective treatment for facial acne scarring. Scar improvement was noted in all treated subjects with minimal discomfort and no downtime. This protocol appears to be most effective at reducing scar depth and softening scar contours. [source]


    Laser Lipolysis Using a Novel 1,064 nm Nd:YAG Laser

    DERMATOLOGIC SURGERY, Issue 2 2006
    KAREN H. KIM MD
    BACKGROUND We studied the safety and efficacy of a 1,064 nm Nd:YAG laser with a 300 ,m fiber for the reduction of small unwanted fat areas. METHODS Thirty subjects with focal areas of fat less than 100 cm3 were enrolled. Ten subjects were treated with laser lipolysis and had magnetic resonance imaging (MRI) at baseline and 3 months post-treatment. Ten subjects had laser lipolysis followed by biweekly treatments with the Tri-active system. The last group of 10 subjects served as control. Patients were seen at baseline, 1 week, 1 month, and 3 month follow-up visits. RESULTS Twenty-nine patients completed the study. Self-assessment evaluations reported an improvement of 37% at the 3-month follow-up visit. MRI demonstrated an average 17% reduction in fat volume. Smaller baseline volume areas, such as the submentum, showed better results, suggesting a dose-response relationship. The most common side effects were mild bruising and swelling resolving within 2 weeks. CONCLUSION Laser lipolysis using the 1,064 nm Nd:YAG laser with 300 ,m fiber appears to be a very promising procedure that delivers good, reproducible results safely and effectively. The advantages include excellent patient tolerance, quick recovery time, as well as the benefit of dermal tightening. [source]


    Variable-Pulse Nd:YAG Laser in the Treatment of Facial Telangiectasias

    DERMATOLOGIC SURGERY, Issue 1 2006
    AVERY A. BEVIN MD
    BACKGROUND Variable-pulse 1,064 nm wavelength lasers have been used with good effectiveness on leg telangiectasias and reticular veins and have shown promising results on facial telangiectasias as well. OBJECTIVE To investigate the effectiveness of a variable-pulse neodymium:yttrium-aluminum-garnet (Nd:YAG) laser using a small spot size in the treatment of facial telangi-ectasias. METHODS Eight male patients (mean age 75 years) underwent a single treatment session using a variable-pulse 1.5 mm spot size Nd:YAG laser with epidermal cooling. Telangiectasia diameters were 0.3 to 2.0 mm. Test sites were performed using three pulse widths (3, 20, and 60 ms), with fluences varying depending on vessel size and response. Full treatments were per-formed using test parameters giving the best response. Thirteen weeks later, the patients returned for final evaluation and satisfaction rating. RESULTS Fluences ranged from 226 to 425 J/cm2, with smaller vessels requiring larger energies. Pulse duration was equally divided between the 20 and 60 ms settings. The shortest pulse width (3 ms) was inferior in all patients. Longer pulse durations achieved superior vessel elimination with minimal immediate purpura and no postinammatory hyperpigmentation. The average mean vessel clearance was 26 to 50% in half of the patients and 51 to 75% in the other half as evaluated by three unbiased dermatologists with extensive laser experience. CONCLUSION A small,spot size Nd:YAG laser using a pulse width of 20 ms or higher appears to be effective in clearing a significant percentage of facial telangectasias with a single pass. The side effects were minimal. [source]


    The Safety and Effectiveness of Single-Pass Erbium:YAG Laser in the Treatment of Mild to Moderate Photodamage

    DERMATOLOGIC SURGERY, Issue 8 2004
    David K. Avram MD
    Background. There are several treatment modalities for mild to moderate photodamage. The demand for effective treatments with minimal side effects has increased. Objective. The objective of this study was to determine the effectiveness of short-pulsed erbium:YAG laser in treating mild to moderate photodamage. Methods. Twenty patients were treated with the short-pulse erbium:YAG laser on the face and neck. One pass was given over the entire face with two to three passes over the perioral and periorbital regions. Patients were evaluated for improvement of pigmentary irregularities, skin texture, and fine wrinkles. All side effects were recorded at follow-up visits. Two lasers were used, Sciton and Cynosure CO3, under local anesthesia. Results. There was a 58% reduction in pigment irregularities and a 54% improvement in skin texture. There was minimal improvement in fine wrinkles with one pass. Two and three passes resulted in a 50% reduction in wrinkles. The procedure was minimally painful. Side effects included 3 to 5 days of erythema and edema. Patients returned to work within 3 days on average. There were no infections. Patient satisfaction with the procedure was rated as very good. There was no difference in efficacy or adverse effects with either laser. Conclusions. One-pass short-pulse erbium:YAG laser in treating photodamage of the face and neck is safe and effective. There are minimal side effects and patients heal within 3 to 5 days. [source]


    Utilization of the 1320-nm Nd:YAG Laser for the Reduction of Photoaging of the Hands

    DERMATOLOGIC SURGERY, Issue 8 2004
    FAACS, Neil Sadick MD
    Background. Nonablative laser resurfacing has been shown to improve the appearance photoaged skin. Clinical improvement has been associated with dermal collagen remodeling. Objective. The objective was to determine the efficacy of a 1320-nm Nd:YAG laser for the treatment of photoaging hands. Methods. Seven patients with photoaged hands received six monthly treatments with a 1320-nm Nd:YAG laser. Improvement in skin smoothness was evaluated by objective and patient assessment using a 6-point improvement scale: 1=no improvement and 6=80% to 100% improvement. Results. Mild to moderate improvement was achieved as determined by both objective and patient assessment. Mean improvement by objective assessment was 2.4 points. Objective improvement was noted in four of seven patients, and these patients demonstrated a mean improvement score of 3.5 points. The mean improvement by patient assessment was 3.1 points. Conclusion. This case series demonstrates that the 1320-nm Nd:YAG laser with cryogen cooling can be effective for rejuvenation of photoaged hands. [source]


    Resurfacing of Different Types of Facial Acne Scar With Short-Pulsed, Variable-Pulsed, and Dual-Mode Er:YAG Laser

    DERMATOLOGIC SURGERY, Issue 4 2004
    Sang-Hyuk Woo MD
    Background. Laser skin resurfacing has become a popular therapeutic modality for the correction of acne scars, but it is not always effective in all types of acne scars. Objective. To evaluate the clinical effects of resurfacing with the short-pulsed Er:YAG laser, the variable-pulsed Er:YAG laser, and the dual-mode Er:YAG laser for each type of facial acne scars. Methods. One hundred fifty-eight patients with facial acne scars were included in this study. Eighty three patients (18 deep boxcar scars, 8 ice-pick scars, 11 rolling scars, and 46 shallow boxcars) were treated with the 350-,s short-pulsed Er:YAG laser at the setting of 12.5 to 15%/cm2. Thirty-five patients (8 deep boxcar scars, 4 ice-pick scars, 12 rolling scars, and 11 shallow boxcars) were treated with the variable-pulsed Er:YAG laser at the setting of 7.0 to 7.5%/cm2 and 7-ms pulse duration. Forty patients (8 deep boxcar scars, 4 ice-pick scars, 17 rolling scars, and 11 shallow boxcars) were treated with the dual-mode Er:YAG laser with 350-, ablation mode at 17.5%/cm2 and 8-ms coagulation mode at 3.15%/cm2. Facial photographs were obtained at baseline and at 2- to 4-week intervals postoperatively. Acne scars were classified into four types, and clinical improvements of facial acne scars were evaluated. Results. Resurfacing with the short-pulsed Er:YAG laser shows good to excellent results for ice-pick and shallow boxcar scars, fair to good for deep boxcar scars, and poor to fair for rolling scars. Resurfacing with the variable-pulsed laser shows good to excellent results for ice-pick and shallow boxcar scars, fair to good for deep boxcar scars, and good for rolling scars. Resurfacing with the dual-mode laser shows good to excellent results for ice-pick, shallow, and rolling scars and produced good results on deep boxcar scars. Conclusion. Shallow boxcar and ice-pick scars can be treated successfully using any types of Er:YAG laser. In cases of rolling and deep boxcar scars, however, Er:YAG laser with a long-pulse duration for a thermal effect is needed for successful treatment. [source]


    Atrophic and a Mixed Pattern of Acne Scars Improved With a 1320-nm Nd:YAG Laser

    DERMATOLOGIC SURGERY, Issue 9 2003
    Arlene S. Rogachefsky MD
    Background. Acne scar correction remains a challenge to the dermatologic surgeon. With nonablative laser resurfacing, this correction is imputed to dermal collagen remodeling and acne scar reorganization. Although atrophic acne scars tend to respond to laser treatment, the deeper ice pick and boxcar scars tend to be laser resistant. Objective. To investigate the treatment of atrophic and a mixed pattern of facial acne scars, we evaluated a 1320-nm Nd:YAG laser. Twelve subjects with atrophic facial acne scars (N=6) or a combination of atrophic and pitted, sclerotic, or boxcar scars (N=6) received three laser treatments. Physician and patient acne scar ratings were performed at baseline and at 6 months after the last treatment. Acne scars were rated with a 10-point severity scale. Results. Mean acne scar improvement was 1.5 points on physician assessments (P=0.002) and 2.2 points on patient assessments (P=0.01). Acne scars were rated more severely by patients than by the physician at all intervals. There were no noted complications at 6 months. Conclusion. The 1320-nm Nd:YAG laser is a safe and effective nonablative modality for the improvement of atrophic and a mixed pattern of facial acne scars. [source]


    Treatment of Pigmented Hypertrophic Scars with the 585 nm Pulsed Dye Laser and the 532 nm Frequency-Doubled Nd:YAG Laser in the Q-Switched and Variable Pulse Modes: A Comparative Study

    DERMATOLOGIC SURGERY, Issue 8 2002
    Leyda Elizabeth Bowes MD
    background. Pigmented hypertrophic scars are a difficult condition to treat. They may result from traumatic injuries or from surgical and cosmetic procedures. The 585 nm flashlamp-pumped pulsed dye laser (FLPDL) has been used to treat this condition, with significant improvement of varying degrees. It remains to be determined whether other laser modalities may have a similar or even greater success in the treatment of pigmented hypertrophic scars. objective. To determine the efficacy of the 532 nm frequency-doubled Nd:YAG laser in the treatment of pigmented hypertrophic scars as compared to the 585 nm FLPDL. methods. Six patients with pigmented hypertrophic scars and skin phototypes II,IV were chosen. A scar was selected for treatment in each patient and divided into four equal 2 cm segments. Three segments were each treated with a different laser modality and one was left untreated to serve as the control. A 585 nm FLPDL was used with an energy of 3.5 J, a pulse duration of 450 ,sec, and a 10 mm spot size. A 532 nm Q-switched frequency-doubled Nd:YAG laser was set to an energy of 2.8 J, a 10-nsec pulse, and a 3 mm spot size. The same 532 nm laser was set to the variable pulse mode to treat a 2 cm scar segment, with an energy of 9.5 J, a 10-msec pulse, and a 4 mm spot size. An average of 3.3 treatments were performed on each scar segment, at intervals of 4,6 weeks and long-term follow-up at 22 weeks. Treatment outcome was graded by a blind observer using the Vancouver General Hospital (VGH) Burn Scar Assessment Scale. A SigmaStat t -test was used to determine the statistical significance of the values obtained. results. Treatment of pigmented hypertrophic scars with the 532 nm Q-switched Nd:YAG laser led to a significant improvement of 38% in the VGH scores when compared to baseline (P = .005). The 585 nm FLPDL also had a favorable effect on the scars, with an average improvement of 36.1% in the VGH scores. There was no significant difference noted between the outcome of treatment with either of these two lasers. Treatment with the 532 nm variable pulse Nd:YAG laser led to a 19% improvement in the VGH scores of scars, which did not differ significantly from the 16.1% improvement observed in control scars on the last follow-up visit. No side effects or complications from treatment were noted or reported during the course of the study. At the conclusion of the study, five of six patients chose the segment treated with the 532 nm Q-switched Nd:YAG laser as the best segment overall. conclusion. The 532 nm Q-switched Nd:YAG laser and the 585 nm FLPDL offer comparable favorable results in the treatment of pigmented hypertrophic scars. The 532 nm Q-switched Nd:YAG laser may be preferred by patients particularly distressed by the dark color of their scars. [source]


    Successful Treatment of Dowling,Degos Disease with Er:YAG Laser

    DERMATOLOGIC SURGERY, Issue 8 2002
    Joerg Wenzel MD
    background. Dowling,Degos disease is a rare condition with a genetically determined disturbance of epidermal proliferation. The typical clinical picture is a reticulate pigmentation of the flexures, genital folds, and pectoral skin areas. Many different treatment options have been tried in recent years without a convincing therapeutic benefit. objective. To determine the effectiveness of Er:YAG laser in Dowling-Degos disease. methods. A 44-year-old woman suffering from Dowling-Degos disease was treated with the Er:YAG laser pulse energy between 1,000 and 1,200 mJ, three consecutive passes. results. The laser treatment led to a good clinical result. conclusion. Our case suggest that treatment with the Er:YAG laser might be a successful strategy in Dowling-Degos disease. [source]


    Re: The Long Pulsed Er:YAG Laser and Intravenous Sedation Versus Dermabrasion (or Laser) Utilizing Tumescent Anesthesia for Colloid Milium

    DERMATOLOGIC SURGERY, Issue 8 2002
    FIACS, Lawrence M. Field MD
    No abstract is available for this article. [source]


    Hair Removal Using a Long-Pulsed Nd:YAG Laser: Comparison at Fluences of 50, 80, and 100 J/cm2

    DERMATOLOGIC SURGERY, Issue 5 2001
    David J. Goldberg MD
    Background. Unwanted hair is a widespread cosmetic problem. Many temporary methods of hair removal have proved unsatisfactory. A variety of laser systems with varying wavelengths, pulse durations, and energy fluences are currently utilized for hair removal. Optimal laser parameters continue to require further investigation. Objective. To evaluate the efficacy and safety of a long-pulse millisecond Nd:YAG hair removal laser utilizing fluences of either 50, 80, or 100 J/cm2. Methods. Fifteen subjects were treated with a contact cooled 50 msec Nd:YAG laser at fluences 30, 50, or 100 J/cm2. Reduction in hair regrowth was measured at 3 months after treatment by comparing the terminal hair count to the baseline values. Potential complications were also evaluated. Results. Average hair reduction at 3 months after treatment was 29%, 29%, and 27% in areas treated with a 50-msec Nd:YAG laser at fluences of 50, 80, and 100 J/cm2, respectively. Although short-term blistering was noted in two subjects, no hyperpimentation, hypopigmentation, or scarring was observed at 3 months after treatment. Conclusion. Long-pulse millisecond Nd:YAG laser hair removal with fluences of either 50, 80, or 100 J/cm2 leads to similar efficacy with no significant adverse effects. [source]


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

    DERMATOLOGIC SURGERY, Issue 4 2001
    Khalil A. Khatri MD
    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 ,sec. 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-,sec 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 ,m and there was decreased bleeding with a 700-,sec pulse duration. Conclusion. The increased pulse duration of Er:YAG laser of 700 ,s does not increase the maximum reported RTD and therefore would not change the recovery time and may have a beneficial effect on hemostasis. [source]


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

    DERMATOLOGIC SURGERY, Issue 2 2001
    Jeung-Tae Jeong MD
    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. [source]


    An Effective Treatment of Dark Lip by Frequency-Doubled Q-Switched Nd:YAG Laser

    DERMATOLOGIC SURGERY, Issue 1 2001
    Somyos Kunachak MD
    Background. Dark lip is a common cosmetic problem in Southeast Asia. There is no known effective treatment. Objective. To propose an effective method for treating dark lips of varying causes with frequency-doubled Q-switched Nd:YAG laser. Methods. Seventy patients with dark lip, of which 22 were congenital, 24 acquired, and 24 of uncertain cause, were treated by frequency-doubled Q-switched Nd:YAG laser at a fluence of 2,3.5 J/cm2 (mode 2.5 J/cm2) after application of topical anesthesia. The endpoint of treatment was complete clearance of the pigment. Follow-up time was 24,36 months (mean 29 months). Results. All patients attained complete clearance of the lesion after an average of 2.5 treatments in the congenital group, 2.2 treatments in the acquired group, and 1.8 treatments in the group with uncertain etiology. The mean (±SD) number of treatments required by the whole group was 2.1 ± 1.4. Recurrence was observed in one case of congenital origin 3 months after the last treatment. In the remaining cases, results persisted up to the time of follow-up. Herpes simplex reactivation was noted in one case 3 days after treatment. There was no dyschromia, scar formation, or change of skin texture. Conclusion. Dark lip can be effectively treated by frequency-doubled Q-switched Nd:YAG laser without major adverse effects. [source]


    Long-term fine caliber hair removal with an electro-optic Q-switched Nd:YAG Laser,

    LASERS IN SURGERY AND MEDICINE, Issue 8 2010
    Abnoeal D. Bakus PhD
    Abstract Background In spite of major advances in hair removal therapy, fine caliber hair remains a significant challenge for laser- and light-based devices. Objective Evaluate a novel Electro-Optic (EO) Q-switched Nd:YAG laser for pigmented fine caliber hair removal in the Standard Single and a double pulse (DP) mode. Methods Eleven patients underwent four laser treatments at monthly intervals. Bilateral anatomical regions received to one side the standard single pulse (SSP) while the other side the DP option. Blinded investigators conducted hair counts at 6 months post-treatment and after 24 months. Patients assessed hair loss and discomfort. Six patients rated their satisfaction at 6 months. Results At 6 months, investigators found a reduction of 50% in hair counts with the DP and 46% with standard pulse. Ninety percent in DP and 50% in SSP reported none to mild discomfort. Transient erythema and edema was observed with a lower severity rating with the DP. There were no other untoward effects. 83.3% of patients who completed the study at 6 months expressed satisfaction with the results. At 24 months hair loss was maintained at the same rate. Conclusion The EO Q-switched Nd:YAG laser is an effective option for the permanent treatment of unwanted fine hair and has a high-patient satisfaction rate. There is less therapeutic discomfort in the DP mode. Lasers Surg. Med. 42:706,711, 2010 © 2010 Wiley-Liss, Inc. [source]


    Tensile bond strength of a flowable composite resin to ER:YAG-laser-treated dentin,

    LASERS IN SURGERY AND MEDICINE, Issue 5 2005
    Juliana Donadio-Moura MSD
    Abstract Background and Objectives This in vitro study evaluated the influence of a flowable composite resin (FCR) on the tensile bond strength of resin to dentin treated with the Er:YAG Laser (L) and diamond bur (DB). Study Design/Materials and Methods Ninety dentin surfaces obtained from 45 third molars were ground and randomly divided into six groups (n,=,15): G1,DB, G2,DB+FCR, G3,L (100 mJ, 10 Hz, 37.04 J/cm2), G4,L (100 mJ, 10 Hz, 37.04 J/cm2)+FCR, G5,L (250 mJ, 2 Hz, 92.60 J/cm2), and G6,L (250 mJ, 2 Hz, 92.60 J/cm2)+FCR. After surface etching with 37% phosphoric acid and the application of an adhesive system, inverted conical specimens were prepared with a hybrid composite resin. In groups G2, G4, and G6 a FCR was placed before the hybrid composite resin. After 24 hours-storage in distilled water, the tensile test was performed in a universal testing machine (0.5 mm/minute, 500 N). Results Data were submitted to Kruskal Wallis test (P,=,0.01). The mean bond strength values (MPa±SD) were: G1,13.54 (±2.99), G2,14.67 (±2.32), G3,9.49 (±3.09), G4,14.60 (±2.76), G5,8.97 (±3.89), and G6,13.02 (±2.18). Groups G1 and G2 presented the highest bond strength values, which were statistically similar to those of G4 and G6. The groups treated with laser and without the FCR (G3 and G5) showed the lowest shear bond strength values. Conclusions FCR can increase the adhesion to dentin treated with Er:YAG laser within different parameters. © 2005 Wiley-Liss, Inc. [source]


    Laser-Assisted Hair Transplantation: Histologic Comparison Between CO2 and Ho:YAG Lasers

    DERMATOLOGIC SURGERY, Issue 4 2001
    Eugene A. Chu MD
    Background. Various laser wavelengths and devices have been advocated for use in the creation of recipient channels during hair transplant surgery, including flash-scanned CO2, Ho:YAG (, = 2.12 ,m), and Er:YAG (, = 2.94 ,m). Objective. To determine the tissue injury caused by flash-scanned CO2 and pulsed Ho:YAG lasers during the creation of hair transplant recipient channels and to assess the efficacy of the Ho:YAG laser. Methods. Recipient channels were created in vivo in human scalp tissue using both lasers, and were excised and prepared for histologic examination. Optical micrometry of tissue sections was used to assess thermal injury. Results. The Ho:YAG laser created jagged, irregular-shaped channels with larger zones of thermal injury (superficial deepithelialization, thermal necrosis, and thermal damage). In contrast, the CO2 laser produced well-defined cylindrically shaped channels free of cellular debris with minimal epithelial disruption and significantly less lateral thermal injury. Conclusion. Given that the Ho:YAG produced larger regions of thermal injury and recipient channels that were unacceptable for graft, the CO2 laser remains the better choice for the creation of recipient channels during hair transplant surgery. However, ongoing research will be necessary to determine the optimal laser wavelength and/or devices for this procedure. [source]


    Growth of tetrakis thiourea potassium iodide as new second order optical material

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 4 2008
    J. Thomas Joseph Prakash
    Abstract A novel organometallic nonlinear optical (NLO) crystal, namely thiourea complex of tetrakis thiourea potassium iodide (TTPI), has been grown by slow evaporation solution growth technique. The harvested crystal is large in size. To our knowledge there is no report is available for the bulk size single crystal of TTPI. This material has a positive temperature coefficient and has been grown by slow evaporation solution growth technique. The grown crystal have been characterized by employing several techniques such as single crystal and powder X-ray diffraction, FTIR, UV-Vis-NIR spectra, thermo gravimetric analyses respectively. Etching studies have also been carried out in order to know the surface defects on the as grown specimen of TTPI. The relative second harmonic generation efficiency have been tested by using Nd:YAG laser as source. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Studies on the structural, thermal and optical behaviour of solution grown organic NLO material: 8-hydroxyquinoline

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2007
    N. Vijayan
    Abstract Single crystal of 8-hydroxyquinoline (8HQ) having chemical formula C9H7NO, an organic nonlinear optical (NLO) material has been successfully grown by slow evaporation solution growth technique at room temperature. The crystal system has been confirmed from the powder X-ray diffraction (PXRD) analysis. The crystalline perfection was evaluated by high resolution X-ray diffractometry (HRXRD). From this analysis we found that the quality of the crystal is quite good. However, a very low angle (tilt angle 14 arc sec) boundary was observed which might be due to entrapping of solvent molecules in the crystal during growth. Its optical behavior has been examined by UV-Vis. analysis, which shows the absence of absorbance between the wavelengths ranging from 400 to 1200 nm. From the thermal analysis it was observed that the material exhibits single sharp weight loss starting at 113°C without any degradation. The laser damage threshold was measured at single shot mode and the SHG behavior has been tested using Nd:YAG laser as a source. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Growth and properties of an organometallic nonlinear optical crystal: bis(isothiocyanato)-bis(4-methylpyridine)zinc(II) (Zn(SCN)2(C6H7N)2)

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2006
    L. Y. Zhu
    Abstract Bis(isothiocyanato)-bis(4-methylpyridine)zinc(II)(Zn(SCN)2(C6H7N)2), (abbreviated as ZBNC) single crystals of optical quality have been grown from acetone solution by the slow temperature-lowering method. Its solubilities at different temperatures in acetone were measured. The X-ray powder diffraction (XRPD) spectroscopy of ZBNC crystal was performed at room temperature. The second harmonic generation (SHG) efficiency was determined by powder technique of Kurtz and Perry using Nd:YAG laser, which is equivalent to KDP crystal. The thermal decomposition process was characterized by thermal gravity and differential thermal analysis (TG\DTA). The specific heat of the crystal is 1440.67 J/mol·K at 325 K. The IR spectrum was recorded in the 500,3500 cm,1 region, using KBr pellets on a Nicolet 170sx FT-IR spectrometer. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Low-Fluence Q-Switched Neodymium-Doped Yttrium Aluminum Garnet Laser for Melasma with Pre- or Post-Treatment Triple Combination Cream

    DERMATOLOGIC SURGERY, Issue 6 2010
    SE-YEONG JEONG MD
    BACKGROUND Topical triple combination (TC) treatment is considered the primary approach to melasma. Recently, collimated low-fluence 1,064-nm Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser treatment has attracted attention as an alternative approach. OBJECTIVES To compare the clinical efficacy and adverse effects of low-fluence Q-switched Nd:YAG laser when performed before and after treatment with topical TC using a split-face crossover design. METHODS Thirteen patients with melasma received topical treatment with TC cream or 1,064-nm Q-switched Nd:YAG laser treatment on opposite sides of the face for 8 weeks, and then treatments were reversed for 8 weeks. Responses were evaluated using the Melasma Area and Severity Index scoring system, spectrophotometry measurements, and a subjective self-assessment method. RESULTS After 16 weeks, better results were seen in subjective assessments when laser treatment was used after 8 weeks of topical TC treatment than before usage of TC. There were no significant adverse effects with the laser treatments. CONCLUSIONS Laser treatment after topical TC cream was found to be safer and more effective than the post-treatment use of topical agents. The authors have indicated no significant interest with commercial supporters. [source]


    Comparison of a Long-Pulse Nd:YAG Laser and a Combined 585/1,064-nm Laser for the Treatment of Acne Scars: A Randomized Split-Face Clinical Study

    DERMATOLOGIC SURGERY, Issue 11 2009
    SEONG UK MIN MD
    BACKGROUND Nonablative laser is gaining popularity because of the low risk of complications, especially in patients with darker skin. OBJECTIVE To compare the efficacy and safety of a long-pulse neodymium-doped yttrium aluminium garnet (Nd:YAG) laser and a combined 585/1,064-nm laser for the treatment of acne scars. MATERIALS AND METHODS Nineteen patients with mild to moderate atrophic acne scars received four long-pulse Nd:YAG laser or combined 585/1,064-nm laser treatment sessions at fortnightly intervals. Treatments were administered randomly in a split-face manner. RESULTS Acne scars showed mild to moderate improvement, with significant Echelle d'évaluation clinique des cicatrices d'acné (ECCA) score reductions, after both treatments. Although intermodality differences were not significant, combined 585/1,064-nm laser was more effective for deep boxcar scars. In patients with combined 585/1,064-nm laser-treated sides that improved more than long-pulse Nd:YAG laser-treated sides, ECCA scores were significantly lower for combined 585/1,064-nm laser treatment. Histologic evaluations revealed significantly greater collagen deposition, although there was no significant difference between the two modalities. Patient satisfaction scores concurred with physicians' evaluations. CONCLUSION Both lasers ameliorated acne scarring with minimal downtime. In light of this finding, optimal outcomes might be achieved when laser treatment types are chosen after considering individual scar type and response. [source]


    Treatment of Melasma Using Variable Square Pulse Er: YAG Laser Resurfacing

    DERMATOLOGIC SURGERY, Issue 3 2009
    RUNGSIMA WANITPHAKDEEDECHA MD
    BACKGROUND Treatment of melasma remains a challenge. Laser treatments show limited efficacy, with a high rate of recurrence and side effects. Recently, variable-pulsed erbium:yttrium aluminum garnet (Er:YAG) lasers have shown favorable results in skin resurfacing, with minimal downtime and adverse effects. OBJECTIVE To determine the efficacy and side effects of variable square pulsed (VSP) Er:YAG laser resurfacing for treatment of epidermal type melasma. METHODS Twenty Thai women with epidermal-type melasma were treated with two passes of VSP Er:YAG laser resurfacing using a 7-mm spot size, pulse duration of 300 ,s, and a fluence of 0.4 J/cm2. Two treatments were given 1 month apart. Visual analog scale (VAS), Melasma Area and Severity Index (MASI) score and melanin index (MI) were measured at baseline and 1, 2, and 4 months after treatment. RESULTS There was a significant improvement in VAS from baseline at 1-, 2-, and 4-month follow-up visits (p<.001). Significant improvement in MASI score at the 2-month visit from baseline (p=.004) was also observed. The average MI measured using melanin reflectance spectrometry measurements corresponded to MASI score rating. CONCLUSIONS VSP Er:YAG laser resurfacing effectively but temporarily improved epidermal-type melasma. Recurrence was observed after the treatment was discontinued. [source]


    Minimally Ablative Erbium:YAG Laser Resurfacing of Facial Atrophic Acne Scars in Asian Skin: A Pilot Study

    DERMATOLOGIC SURGERY, Issue 5 2008
    YONG-KWANG TAY MD
    BACKGROUND Atrophic scars are dermal depressions caused by collagen damage most commonly occurring after inflammatory acne vulgaris. There are little published data regarding the effectiveness and safety of minimally invasive lasers in the treatment of atrophic acne scars in darker skin types. OBJECTIVE The purpose was to evaluate the efficacy and safety of a low-fluence 2,940-nm erbium:YAG laser in the treatment of atrophic acne scars in Asian patients. MATERIALS AND METHODS Nine patients aged 19 to 45 years with mild to moderate atrophic facial scars and Skin Types IV and V were treated with topical anesthesia and one to two passes with an erbium:YAG laser two times at 1-month intervals. Treatment parameters were 6-mm spot size, fluence of 400 mJ, pulse duration of 300 ,s, and repetition rate of 2 Hz. RESULTS At 2 months after the last treatment, mild to moderate clinical improvement was noted in all patients compared to baseline. Treatment was well tolerated. Side effects consisted of posttreatment erythema, peeling, and crusting, which resolved within 1 to 2 weeks. There was no postinflammatory hyper- or hypopigmentation, blistering, or hypertrophic scarring. CONCLUSION Low-fluence erbium:YAG facial resurfacing was effective and safe in patients with mild to moderately severe atrophic acne scarring. [source]


    A Randomized Trial to Determine the Influence of Laser Therapy, Monopolar Radiofrequency Treatment, and Intense Pulsed Light Therapy Administered Immediately after Hyaluronic Acid Gel Implantation

    DERMATOLOGIC SURGERY, Issue 5 2007
    MITCHEL P. GOLDMAN MD
    BACKGROUND Hyaluronic acid-based dermal fillers, such as hyaluronic acid gel (Restylane, Q-Medical AB, Uppsala, Sweden), are widely used for tissue augmentation of the nasolabial folds. Additional dermatologic treatments using infrared light, radiofrequency (RF), and intense pulsed light (IPL) are also important tools for facial rejuvenation. This study was designed to evaluate whether these therapies could be safely administered immediately after hyaluronic acid gel treatment without compromising the effect of the dermal filler. OBJECTIVE The objective of this study was to confirm or refute any possible subtractive effects of augmentation of the nasolabial folds when followed by 1,320-nm Nd:YAG laser, 1,450-nm diode laser, monopolar RF, and/or IPL treatments. METHODS Thirty-six patients with prominent nasolabial folds were treated with hyaluronic acid gel implantation on one side of the face and hyaluronic acid gel followed by one of the nonablative laser/RF/IPL therapies on the contralateral side of the face. RESULTS There were no statistically significant differences between wrinkle severity or global aesthetic scores for hyaluronic acid gel implantation alone and hyaluronic acid gel with laser/RF/IPL treatment at any time point. In a small sample, histologic changes were not apparent after laser/RF/IPL treatment. CONCLUSIONS Based on this small pilot study, laser, RF, and IPL treatments can safely be administered immediately after hyaluronic acid gel implantation without reduction in overall clinical effect. [source]


    Nonablative Acne Scar Reduction after a Series of Treatments with a Short-Pulsed 1,064-nm Neodymium:YAG Laser

    DERMATOLOGIC SURGERY, Issue 8 2006
    GRAEME M. LIPPER MD
    BACKGROUND Effective treatment of facial acne scarring presents a major challenge. Nonablative lasers and radiofrequency devices work by thermally stimulating dermal collagen remodeling, thereby softening acne scars in a minimally invasive fashion. One such laser, a 1,064-nm short-pulsed Nd:YAG, uses rapidly scanned low-energy infrared pulses to heat the dermis selectively through the normal dermal microvasculature. OBJECTIVE In this pilot study, the safety and efficacy of a novel short-pulsed Nd:YAG laser were investigated for the treatment of moderate to severe facial acne scarring. MATERIALS AND METHODS Nine of 10 enrolled patients with moderate to severe facial acne scarring received eight sequential 1,064-nm Nd:YAG treatments (laser parameters 14 J/cm2, 0.3 milliseconds, 5-mm spot size, 7-Hz pulse rate, 2,000 pulses per side of face). Patients were graded for the presence and severity of three scar morphologies: superficial (rolling), medium-depth (boxcar), and deep (ice pick). Outcome measures included blinded evaluation of before and after photographs by three physician observers (scar severity score) and patient self-assessment. RESULTS Acne scarring improved in 100% of the nine patients completing the study. Scar severity scores improved by a mean of 29.36% (95% confidence interval, 16.93%,41.79%; p=.006); 89% of patients noted greater than 10% scar improvement. No treatment-related adverse events were seen. CONCLUSION Our findings support the use of a short-pulsed, low-fluence 1,064-nm Nd:YAG laser as a safe, effective treatment for facial acne scarring. Scar improvement was noted in all treated subjects with minimal discomfort and no downtime. This protocol appears to be most effective at reducing scar depth and softening scar contours. [source]


    Patient Satisfaction and Reported Long-Term Therapeutic Efficacy Associated with 1,320 nm Nd:YAG Laser Treatment of Acne Scarring and Photoaging

    DERMATOLOGIC SURGERY, Issue 3 2006
    ASHISH C. BHATIA
    BACKGROUND AND OBJECTIVE Nonablative laser treatments have become increasingly used for the treatment of acne scarring and photoaging. While nonablative laser treatments are more convenient and relatively safer than ablative laser resurfacing, efficacy and patient satisfaction with the level of improvement of textural abnormalities in acne scarring and rhytids associated with photoaging needs further study. DESIGN/MATERIALS AND METHODS Structured interviews were performed with 34 patients from a referral-based academic practice who each previously received a series of 6 monthly treatments with a 1,320 nm neodymium:yttrium,aluminum,garnet (Nd:YAG) laser for treatment of acne scarring or photoaging. Topical anesthesia was applied 1 hour before each treatment. Patients were interviewed at least 3 months after cessation of treatment (range 3,12 months). RESULTS Patients tolerated the treatments well. Combined results for acne scarring and photoaging patients were as follows: (a) patient satisfaction with treatment was rated at 62%, and (b) textural improvement was reported at 31% at the end of the six treatments, and 30% at the date of interview. When results were stratified by diagnosis, patient satisfaction was slightly higher for treatment of acne scarring than for photoaging. Overall degree of improvement on a 1,10 scale was 5.4 for acne scarring and 3.8 for wrinkling. CONCLUSION Nonablative treatment with the 1,320 nm Nd:YAG laser induced significant patient-reported improvement in both acne scarring and photoaging. The majority of patients reported satisfaction with the degree of improvement. [source]


    Laser Lipolysis Using a Novel 1,064 nm Nd:YAG Laser

    DERMATOLOGIC SURGERY, Issue 2 2006
    KAREN H. KIM MD
    BACKGROUND We studied the safety and efficacy of a 1,064 nm Nd:YAG laser with a 300 ,m fiber for the reduction of small unwanted fat areas. METHODS Thirty subjects with focal areas of fat less than 100 cm3 were enrolled. Ten subjects were treated with laser lipolysis and had magnetic resonance imaging (MRI) at baseline and 3 months post-treatment. Ten subjects had laser lipolysis followed by biweekly treatments with the Tri-active system. The last group of 10 subjects served as control. Patients were seen at baseline, 1 week, 1 month, and 3 month follow-up visits. RESULTS Twenty-nine patients completed the study. Self-assessment evaluations reported an improvement of 37% at the 3-month follow-up visit. MRI demonstrated an average 17% reduction in fat volume. Smaller baseline volume areas, such as the submentum, showed better results, suggesting a dose-response relationship. The most common side effects were mild bruising and swelling resolving within 2 weeks. CONCLUSION Laser lipolysis using the 1,064 nm Nd:YAG laser with 300 ,m fiber appears to be a very promising procedure that delivers good, reproducible results safely and effectively. The advantages include excellent patient tolerance, quick recovery time, as well as the benefit of dermal tightening. [source]


    Variable-Pulse Nd:YAG Laser in the Treatment of Facial Telangiectasias

    DERMATOLOGIC SURGERY, Issue 1 2006
    AVERY A. BEVIN MD
    BACKGROUND Variable-pulse 1,064 nm wavelength lasers have been used with good effectiveness on leg telangiectasias and reticular veins and have shown promising results on facial telangiectasias as well. OBJECTIVE To investigate the effectiveness of a variable-pulse neodymium:yttrium-aluminum-garnet (Nd:YAG) laser using a small spot size in the treatment of facial telangi-ectasias. METHODS Eight male patients (mean age 75 years) underwent a single treatment session using a variable-pulse 1.5 mm spot size Nd:YAG laser with epidermal cooling. Telangiectasia diameters were 0.3 to 2.0 mm. Test sites were performed using three pulse widths (3, 20, and 60 ms), with fluences varying depending on vessel size and response. Full treatments were per-formed using test parameters giving the best response. Thirteen weeks later, the patients returned for final evaluation and satisfaction rating. RESULTS Fluences ranged from 226 to 425 J/cm2, with smaller vessels requiring larger energies. Pulse duration was equally divided between the 20 and 60 ms settings. The shortest pulse width (3 ms) was inferior in all patients. Longer pulse durations achieved superior vessel elimination with minimal immediate purpura and no postinammatory hyperpigmentation. The average mean vessel clearance was 26 to 50% in half of the patients and 51 to 75% in the other half as evaluated by three unbiased dermatologists with extensive laser experience. CONCLUSION A small,spot size Nd:YAG laser using a pulse width of 20 ms or higher appears to be effective in clearing a significant percentage of facial telangectasias with a single pass. The side effects were minimal. [source]