Nm Diode Laser (nm + diode_laser)

Distribution by Scientific Domains


Selected Abstracts


Pilonidal Sinus Disease Treated by Depilation Using an 800 nm Diode Laser and Review of the Literature

DERMATOLOGIC SURGERY, Issue 5 2005
Anthony V. Benedetto DO, FACP
background. Pilonidal sinus disease is a debilitating, disfiguring chronic ailment that is often resistant to therapy. Its etiology and treatment remain in question. objective. To assess the efficacy of an 800 nm diode laser in the treatment of recalcitrant pilonidal sinus disease. methods. Two patients with recalcitrant pilonidal sinus disease were treated in the lower back, buttocks, and perigluteal cleft area with an 800 nm diode laser with a spot size of 9 × 9 mm, fluences of 30 to 48 J/cm2, and pulse widths of 15 to 24 milliseconds. results. Long-term relief of pilonidal sinus disease was produced with as few as two treatments 2 months apart to as many as six treatments over a 2-year period. With each successive treatment, fewer pulses were needed and the interval between treatments increased. conclusion. The 800 nm diode laser may be an effective tool in the treatment of pilonidal sinus disease. By eliminating the source of hair and hair fragments that course along the surface of the lower back and buttocks, interruption of the etiologic source for pilonidal sinus disease can be accomplished. [source]


Effective Treatment of Leg Vein Telangiectasia with a New 940 nm Diode Laser

DERMATOLOGIC SURGERY, Issue 2 2001
Peter Kaudewitz MD
Background. A variety of lasers have been used in an attempt to treat leg vein telangiectasia Objective. To evaluate the feasibility of a new 940 nm diode laser for the treatment of leg vein telangiectasia. Methods. Thirty-one patients with leg vein telangiectasia were treated with a diode laser; 26 of these with 940 nm, 300,350 J/cm2, 40,70 msec, 1.0 mm handpiece, one pass, and 5 of these with 940 nm, 815 J/cm2, 50 msec, 0.5 mm handpiece, one pass. Each subject had three treatments of the same site at 4-week intervals. Photographs taken before and 4 weeks after the last treatment were evaluated by two independent observers for vessel clearance. Results. In those 26 patients treated with a fluence of 300,350 J/cm2, a vessel clearance of greater than 50% was achieved in 20 patients (76%), 12 of these patients had clearance rates greater than 75%. A clearance rate of less than 50% was obtained in six patients, with three of these patients showing responses of less than 25%. In five patients treated with a fluence of 815 J/cm2 a clearance rate of more than 75% was observed. Conclusions. In this preliminary study a 940 nm diode laser was shown to be safe and effective for the treatment of leg vein telangiectasia. [source]


Pilonidal Sinus Disease Treated by Depilation Using an 800 nm Diode Laser and Review of the Literature

DERMATOLOGIC SURGERY, Issue 5 2005
Anthony V. Benedetto DO, FACP
background. Pilonidal sinus disease is a debilitating, disfiguring chronic ailment that is often resistant to therapy. Its etiology and treatment remain in question. objective. To assess the efficacy of an 800 nm diode laser in the treatment of recalcitrant pilonidal sinus disease. methods. Two patients with recalcitrant pilonidal sinus disease were treated in the lower back, buttocks, and perigluteal cleft area with an 800 nm diode laser with a spot size of 9 × 9 mm, fluences of 30 to 48 J/cm2, and pulse widths of 15 to 24 milliseconds. results. Long-term relief of pilonidal sinus disease was produced with as few as two treatments 2 months apart to as many as six treatments over a 2-year period. With each successive treatment, fewer pulses were needed and the interval between treatments increased. conclusion. The 800 nm diode laser may be an effective tool in the treatment of pilonidal sinus disease. By eliminating the source of hair and hair fragments that course along the surface of the lower back and buttocks, interruption of the etiologic source for pilonidal sinus disease can be accomplished. [source]


Nonablative 1450-nm Diode Laser in the Treatment of Facial Atrophic Acne Scars in Type IV to V Asian Skin: A Prospective Clinical Study

DERMATOLOGIC SURGERY, Issue 10 2004
Sze-Hon Chua MRCP (UK)
Background. There is presently little published data on the clinical effectiveness of nonablative lasers in the treatment of atrophic acne scars and the safety of their use in patients with darker skin types. Objective. This study aims to determine the clinical effectiveness and safety of the nonablative 1450 nm diode laser with cryogen cooling spray in the treatment of facial atrophic acne scars in Type IV-V Asian skin. Methods. This is a prospective non-comparative open study. 4 to 6 laser treatment sessions were performed on patients with atrophic acne scars. Final clinical assessment was performed 6 months after the last treatment. Results. 57 patients were evaluated. Patient's self-assessment of scar improvement as compared with doctor's assessment was as follows: patients who completed 4 treatments (15.7% vs 6.6%), patients who completed 5 treatments (20% vs 7.9%) and patients those who completed 6 treatments (17.3% vs 5.0%). Main side effects were mild to moderate pain during the procedure, transient erythema, and hyperpigmentation which occurred in 39% of treated patients. Conclusion. The nonablative 1450 nm diode laser may be effective in achieving mild to moderate gradual clinical improvement in the treatment of facial atrophic acne scars. The procedure is associated with minimal downtime and is safe for use in darker skin types IV and V. [source]


Comparison of Endovenous Radiofrequency Versus 810 nm Diode Laser Occlusion of Large Veins in an Animal Model

DERMATOLOGIC SURGERY, Issue 1 2002
Robert A. Weiss MDArticle first published online: 27 FEB 200
background. Endovenous occlusion using radiofrequency (RF) energy has been shown to be effective for the elimination of sapheno-femoral reflux and subsequent elimination of varicose veins. Recently, endovenous laser occlusion has been introduced with initial clinical reports indicating effective treatment for varicose veins. However, in our practice we note increased peri-operative hematoma and tenderness with the laser. Little is known regarding the mechanism of action of this new laser vein therapy. objective. To better understand the mechanism of action of endovenous laser vs. the endovenous RF procedure in the jugular vein of the goat model. methods. A bilateral comparison was performed using 810 nm diode laser transmitted by a bare-tipped optical fiber vs. the RF delivery by engineered electrodes with a temperature feedback loop using a thermocouple (Closure procedure) in three goat jugular veins. Immediate and one-week results were studied radiographically and histologically. Temperature measurements during laser treatment were performed by using an array of up to five thermocouples, spaced 2 mm apart, placed adjacent to a laser fiber tip during goat jugular vein treatment. results. Immediate findings showed that 100% of the laser-treated veins showed perforations by histologic examination and immediate contrast fluoroscopy. The RF-treated side showed immediate constriction with maintenance of contrast material within the vein lumen and no perforations. The difference in acute vein shrinkage was also dramatic as laser treatments resulted in vein shrinkage of 26%, while RF-treated veins showed a 77% acute reduction in diameter. At one week, extravasated blood that leaked into the surrounding tissue of laser treated veins acutely, continued to occupy space and impinge on surrounding structures including nerves. For the laser treatment, the highest average temperature was 729°C (peak temperature 1334°C) observed flush with the laser fiber tip, while the temperature feedback mechanism of the RF method maintains temperatures at the electrodes of 85°C. conclusion. Vein perforations, extremely high intravascular temperatures, failure to cause significant collagen shrinkage, and intact endothelium in an animal model justify a closer look at the human clinical application of the 810 nm endovenous laser technique. Extravasated blood impinging on adjacent structures may theoretically lead to increased peri-operative hematoma and tenderness. Further study and clinical investigation is warranted. [source]


Effective Treatment of Leg Vein Telangiectasia with a New 940 nm Diode Laser

DERMATOLOGIC SURGERY, Issue 2 2001
Peter Kaudewitz MD
Background. A variety of lasers have been used in an attempt to treat leg vein telangiectasia Objective. To evaluate the feasibility of a new 940 nm diode laser for the treatment of leg vein telangiectasia. Methods. Thirty-one patients with leg vein telangiectasia were treated with a diode laser; 26 of these with 940 nm, 300,350 J/cm2, 40,70 msec, 1.0 mm handpiece, one pass, and 5 of these with 940 nm, 815 J/cm2, 50 msec, 0.5 mm handpiece, one pass. Each subject had three treatments of the same site at 4-week intervals. Photographs taken before and 4 weeks after the last treatment were evaluated by two independent observers for vessel clearance. Results. In those 26 patients treated with a fluence of 300,350 J/cm2, a vessel clearance of greater than 50% was achieved in 20 patients (76%), 12 of these patients had clearance rates greater than 75%. A clearance rate of less than 50% was obtained in six patients, with three of these patients showing responses of less than 25%. In five patients treated with a fluence of 815 J/cm2 a clearance rate of more than 75% was observed. Conclusions. In this preliminary study a 940 nm diode laser was shown to be safe and effective for the treatment of leg vein telangiectasia. [source]


Bond strength of AH Plus and Epiphany sealers on root dentine irradiated with 980 nm diode laser

INTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2008
E. Alfredo
Abstract Aim, To evaluate the bond strength of AH Plus and Epiphany sealers to human root canal dentine irradiated with a 980 nm diode laser at different power and frequency parameters, using the push-out test. Methodology, Sixty canine roots were sectioned below the cementoenamel junction to provide 4-mm-thick dentine discs that had their root canals prepared with a tapered bur and irrigated with sodium hypochlorite, ethylenediaminetetraacetic acid and distilled water. The specimens were assigned to five groups (n = 12): one control (no laser) and four experimental groups that were submitted to 980 nm diode laser irradiation at different power (1.5 and 3.0 W) and frequency (continuous wave and 100 Hz) parameters. Half of specimens in each group had their canals filled with AH Plus sealer and half with Epiphany. The push-out test was performed and data (MPa) were analysed statistically by anova and Tukey's test (P < 0.05). The specimens were split longitudinally and examined under SEM to assess the failure modes after sealer displacement. Results, The specimens irradiated with the diode laser and filled with AH Plus had significantly higher bond strength values (8.69 ± 2.44) than those irradiated and filled with Epiphany (3.28 ± 1.58) and the nonirradiated controls (3.86 ± 0.60). The specimens filled with Epiphany did not differ significantly to each other or to the control (1.75 ± 0.69). There was a predominance of adhesive failures at Epiphany,dentine interface (77%) and mixed failures at AH Plus,dentine interface (67%). Conclusions, The 980 nm diode laser irradiation of root canal dentine increased the bond strength of AH Plus sealer, but did not affect the adhesion of Epiphany sealer. [source]


Tunable narrow linewidth Tm3+ -doped silica fiber laser with an intracavity taper

LASER PHYSICS LETTERS, Issue 3 2010
Y. Zhang
Abstract Using an intracavity long fiber taper, the 793 nm diode laser (LD) clad-pumped tunable narrow linewidth Tm3+ -doped silica fiber laser was realized. The intracavity long taper was fabricated directly on the Tm3+ -doped fiber by heating and stretching method, and located several centimeters from the output fiber end. The fiber laser cavity was combined by the fiber end Fresnel reflection and a dichroic. The fiber laser had a maximal output power of 5.86 W at 1927.2 nm, with a narrow linewidth of 148 pm. By stretching or bending the taper, the output laser center wavelength could be tuned from 1910.6 nm to 1958.1 nm with a variable spectrum width ranging from 92 , 148 pm. (© 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]


Histological changes occurring after endoluminal ablation with two diode lasers (940 and 1319 nm) from acute changes to 4 months

LASERS IN SURGERY AND MEDICINE, Issue 10 2008
FACS, Ronald G. Bush MD
Abstract Background Endovenous laser ablation of the saphenous vein was studied from a histologic analysis to establish changes that occur from time of injury to 4 months when the vein is difficult to visualize by ultrasound. Methods Twenty-four patients were examined after treatment with either a 1319 nm diode laser (Sciton, Palo Alto, CA) or a 940 nm diode (Dornier, Kennasaw, GA) 12 patients were randomly assigned to the 940 nm group and 12 patients to the 1319 nm group. Histologic evaluations were only done once per patient. All patients had symptomatic saphenous insufficiency with varicosities. All were in CEAP class 3 or 4. Sections of treated veins were submitted for evaluation after staining with hematoxylin,eosin. The evaluations were done acutely, at 1 and 4 months. Ultrasound findings were also evaluated and compared at the same intervals. Results Acutely, all examined veins revealed loss of intima. In the 1319 nm group numerous vacuoles were present in the subintimal layer. On gross exam at 1 month, both groups showed vein wall thickening, intraluminal thrombus and inflammatory changes. Histologic evaluation showed thrombus was present with many fibroblasts and inflammatory cells. At 4 months, collagen was the predominant histologic finding. However, the changes were less in regards to the injury response with the 1,319 nm group as manifested by less collagen deposition at 4 months. Conclusion This study demonstrates the cellular sequence that occurs after endovenous ablation. Fibroblast infiltration is a result of the injury response which leads to negative modeling of the thrombus and eventual collagen deposition. Replacement of the thrombus with collagen is necessary for eventual long-term success. Lasers Surg. Med. 40:676,679, 2008. © 2008 Wiley-Liss, Inc. [source]


Clinical effect of low-energy double-pass 1450 nm laser treatment for acne in Asians

PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 1 2009
Reiko Noborio
Background: While the 1450 nm diode laser is highly effective for the treatment of acne, its use is associated with considerable pain. Low-energy, double-pass irradiation was attempted as an alternative to prevent the occurrence of pain as an adverse effect. Purpose: This study aimed to evaluate the clinical efficacy of low-energy, double-pass, 1450 nm diode laser treatment in the treatment of acne in Asian patients. Methods: Thirty Japanese patients with inflammatory acne were treated with the low-energy, double-pass, 1450 nm diode laser at 2,4-week intervals. An open study was performed in patients that underwent at least five and up to 10 treatment sessions. The clinical effect was assessed using an acne grading scale. Results: Of the 30 patients, 27 completed the study. The mean acne grades decreased from 3.9 to 1.4 (P<0.01) in the 27 patients. The pain was tolerated by 25 patients, and two patients required local anesthesia. No remarkable side effects occurred in any of the patients; all but a few patients had transient faint erythema. Conclusion: Low-energy, double-pass therapy is an alternative method that is beneficial for patients who complain of considerable pain. Furthermore, the method may have a lower risk of transient hyperpigmentation induced by cryogen spray, even in Asian patients who tend to develop inflammatory pigmentation. [source]


Laser Hair Removal with Alexandrite versus Diode Laser Using Four Treatment Sessions: 1-Year Results

DERMATOLOGIC SURGERY, Issue 11 2001
Sorin Eremia MD
Background. Laser hair removal is the treatment of choice for hypertrichosis. The two most commonly used hair removal lasers are compared. Objective. To present the results of a comparative study examining the role of wavelength, fluence, spot size, pulse width, and cooling systems on long-term results after a series of four laser hair removal treatments using the 755 nm alexandrite and 800,810 nm diode lasers. Methods. The axillae of 15 untanned, type I,V patients were treated side by side four times at 4- to 6-week intervals with a 755 nm, 3-msec pulse width, cryogen spray-equipped alexandrite laser and an 800 nm, variable pulse width, cooled sapphire window-equipped diode laser. Each patient was pretested and treated with the maximum fluence tolerated at the largest spot size available for each laser (12 mm round/113 mm2 for the alexandrite and 9 mm for the diode). Results. Evaluations were done at 3, 6, 9, and 12 months after the last treatment. Twelve-month results with the alexandrite and diode lasers achieved 85% versus 84% hair reduction. The fact that tan avoidance was strictly followed permitted the use of relatively high fluences (25,30+ J/cm2) even in type IV patients. For most patients, four treatment sessions using high fluences (30,40 J/cm2) with relatively large spot sizes (12 mm round for the 755 nm alexandrite and 9 mm for the 800 nm diode) resulted in 12-month hair reductions in the 90% range. Conclusion. Both the alexandrite and diode lasers in this 12-month study produced excellent long-term hair reductions. [source]