Flashlamp-pumped Pulsed Dye Laser Research Articles

Effect of Pulse Width of a 595-nm Flashlamp-Pumped Pulsed Dye Laser on the Treatment Response of Keloidal and Hypertrophic Sternotomy Scars

Flashlamp-pumped pulsed dye lasers (PDLs) have successfully treated keloidal and hypertrophic scars. The objective was to investigate the effect of pulse width of a PDL in treating keloidal and hypertrophic scars. On each of 19 patients, keloidal or hypertrophic median sternotomy scars were divided into two segments. Both segments on all patients were randomly treated with a 595-nm PDL at a fluence of 7 J/cm(2) and pulse widths of 0.45 and 40 ms to both segments, every 4 weeks for a total of three treatments. Scar volume, height, erythema, and pliability were measured at Weeks 0, 4, 8, and 24. The volume of segments treated with 0.45- and 40-ms pulses decreased significantly after two treatments. Segments treated with a 0.45-ms pulse width showed significantly greater improvement than those treated with 40-ms pulses after three treatments. Elasticity of 0.45-ms segments was significantly higher than those of 40-ms segments, following two treatments. Pulse width had no significant effect in improvement of scar erythema. A pulse width of 0.45 ms of PDL was more effective in decreasing scar size and improving scar pliability than that of 40 ms. A 595-nm PDL was safe and effective in treatment of hypertrophic scars and keloids in dark-skinned individuals. This study was supported in part by an educational grant from the Dermatological Society of Thailand.

Effect of Pulse Width of a 595-nm Flashlamp-Pumped Pulsed Dye Laser on the Treatment Response of Keloidal and Hypertrophic Sternotomy Scars

Effect of Pulse Width of a 595-nm Flashlamp-Pumped Pulsed Dye Laser on the Treatment Response of Keloidal and Hypertrophic Sternotomy Scars

Effects of lower fluence pulsed dye laser irradiation on production of collagen and the mRNA expression of collagen relative gene in cultured fibroblasts in vitro

Lower fluence of 585-nm flashlamp-pumped pulsed dye laser has been successfully used as a nonablative technique in the treatment of wrinkles. The objective of this study was to evaluate the effect of the pulsed dye laser (585 nm) on the production of collagen and the mRNA expression of collagen related gene in fibroblasts in vitro. Cultured fibroblasts were treated with a 585-nm flashlamp-pumped pulsed dye laser (fluence 3 J/cm(2), 4 J/cm(2), spot size 7 mm, pulse duration 450 micros). The production of collagen and the mRNA expression of transforming growth factor (TGF)-beta1, SMAD2, SMAD3, SMAD4, SMAD7 and type I procollagen alpha1, alpha2 in fibroblasts were investigated by colorimetry or real time polymerase chain reaction. The production of collagen was significantly up-regulated after treatment with a 585-nm flashlamp-pumped pulsed dye laser with a fluence of 3 J/cm(2) (P < 0.001). The mRNA expression of TGF-beta1, SMAD2, SMAD3, SMAD4, SMAD7 and procollagen I was significantly up-regulated after treatment with a 585-nm flashlamp-pumped pulsed dye laser with a fluence of 3 J/cm(2) (P < 0.001). No significant difference of mRNA expression of SMAD2, SMAD3, SMAD4, SMAD7 and type I procollagen was found between controls and fibroblasts treated with pulsed dye laser with a fluence of 4 J/cm(2) (P > 0.05). Lower fluence (3 J/cm(2)) pulsed dye laser increased the collagen production in fibroblasts by up-regulating TGF-beta1, SMAD2, SMAD3, SMAD4, SMAD7 and type I procollagen mRNA expression. These may be the reason it can be effectively used in the treatment of wrinkles.

New Combination of Triamcinolone, 5-Fluorouracil, and Pulsed-Dye Laser for Treatment of Keloid and Hypertrophic Scars

Keloids and hypertrophic scars are benign growths of dermal collagen that usually cause major physical, psychological, and cosmetic problems. In this 12-week single-blinded clinical trial, 69 patients were randomly assigned into three study groups. In Group 1, intralesional triamcinolone acetonide (TAC, 10 mg/mL) was injected at weekly intervals for a total of 8 weeks. In Group 2 [TAC+5-fluorouracil (5-FU)], 0.1 mL of 40 mg/mL TAC was added to 0.9 mL of 5-FU (50 mg/mL). This combination was injected weekly for 8 weeks. In Group 3, in addition to weekly TAC+5-FU injection for 8 weeks, lesions were irradiated by 585-nm flashlamp-pumped pulsed-dye laser (PDL, 5-7.5 J/cm2) at the 1st, 4th, and 8th weeks. Lesions were assessed for erythema, pruritus, pliability, height, length, and width. Sixty patients completed the study. At the 8- and 12-week follow-up visits, all groups showed an acceptable improvement in nearly all measures, but in comparison between groups, these were statistically more significant in the TAC+5-FU and TAC+5-FU+PDL groups (p<.05 for all). At the end of the study, the erythema score was significantly lower, and itch reduction was statistically higher in the TAC+5-FU+PDL group (p<.05 for both). Good to excellent improvements (>50% improvement) were reported by the patients as follows: 20% in Group 1, 55% in Group 2, and 75% in Group 3, all of which were significantly different (p<.05). Good to excellent responses were reported by the blinded observer as follows: 15% in Group 1, 40% in Group 2, and 70% in Group 3. Their differences were statistically significant (p<.05). Atrophy and telangiectasia were seen in 37% of patients in TAC group. Overall efficacy of TAC+5-FU was comparable with TAC+5-FU+PDL, but the TAC+5-FU+PDL combination was more acceptable by the patients and produced better results. Its effect on lightening of the lesion was promising. The TAC+5-FU+PDL combination seems to be the best approach for treatment of keloid and hypertrophic scars.

Treatment of Granuloma Annulare with the 585 nm Pulsed Dye Laser

Granuloma annulare is a chronic asymptomatic dermatosis that is typically manifested by annular papules arising on the dorsa of the hands, feet, elbows, and knees. Multiple treatment modalities have been used with variable efficacy, but no known cure exists. Obtaining long-term resolution of involved areas is often a therapeutic challenge. We report the results of treatment of a patient with localized erythematous granuloma annulare with a 585 nm flashlamp-pumped pulsed dye laser. A single granuloma annulare plaque present on the left wrist for 3 years was treated on three occasions with a 585 nm flashlamp-pumped pulsed dye laser initially and repeated at months 5 and 13. After initial pulsed dye laser treatment, significant flattening and reduction of erythema were evident within the treated area. After a second treatment at month 5 and a third treatment at month 13, further improvement was evident, and long-term remission was achieved. Localized granuloma annulare may be difficult to manage, presenting a therapeutic challenge. Thorough understanding of available treatment options, their relative efficacies, and risks of complication can facilitate successful management of this chronic disease. Pulsed dye laser therapy may be an effective and relatively safe treatment option for erythematous granuloma annulare, although prospective studies in additional patients would be desirable. Improvement of the condition in a single patient does not imply that others might improve, and variability in response is more likely.

Pulsed dye laser treatment of genital warts

Genital warts represent benign epithelial proliferations induced by human papillomavirus. The goal of treatment is the clearance of visible warts. Different regimens are available. Flashlamp-pumped pulsed dye laser (FPDL) represents one of many treatment options for the management of viral warts (verrucae vulgares), its effectiveness being comparable with that of conventional therapies. We evaluated the effectivity of FPDL light for the treatment of genital warts. A prospective study was performed to examine the efficacy of FPDL in untreated genital warts in which 22 patients were included. All patients showed complete remission after 1.59 (1-5) laser sessions and no scarring was observed. This study demonstrate that FPDL is a simple and safe, cost and time saving alternative treatment option for genital warts and should be listed in genital warts treatment guidelines.

Laser-assisted angioplasty for arterial occlusion of the lower limb: initial results and follow-up

A flashlamp-pumped pulsed dye laser operating at either 480 or 504 nm, coupled to an integral ball-tipped optical fibre, was used to recanalize occluded lower limb arteries. All channels created by the laser were augmented with balloon dilatation. We have treated 78 limbs in 71 patients; 46 limbs (59 per cent) had rest pain and 22 (48 per cent) of these had tissue loss. The median occlusion length was 18 (range 0.5-58) cm. Technical success was achieved in 58 limbs (74 per cent) with clinical success in 46 (59 per cent). Success rates fell with increasing length of occlusion. Two patients died in the perioperative period. A subgroup of 22 patients with marked discrete arterial calcification had a lower technical success rate than the subgroup without calcification (50 per cent versus 84 per cent, P less than 0.01). Both subgroups displayed a similar pattern of reclosure during follow-up. The cumulative patency rate after technical success was 67 per cent at 6 months and 45 per cent at 12 months. Forty-six (59 per cent) limbs avoided bypass surgery or amputation. Laser-assisted angioplasty may offer an alternative to femoropopliteal bypass, although the former procedure is not as durable.

Selective Photothermolysis of Blood Vessels Following Flashlamp-Pumped Pulsed Dye Laser Irradiation: In Vivo Results and Mathematical Modelling Are in Agreement

Laser therapy using the pulsed dye laser is the standard treatment for port-wine stains (PWS). But the mechanism of action has not been elucidated completely, yet. The dorsal skin-fold chamber model in hamsters was used to investigate the effects of laser treatment (lambda(em)=585 nm; pulse duration: 0.45 ms; fluence: 6 J per cm2) on blood vessels. Vessels (n=3394) were marked with FITC dextran (MW 150 kDa) and diameters (2-186 microm) were measured using intravital fluorescence microscopy up to 24 h following irradiation. Histology (H&E, TUNEL, CD31) was taken 1 or 24 h after irradiation. The experimental results were compared with the predictions of a mathematical model based on the finite-element method. Following irradiation treatment the number of unperfused vessels decreases with decreasing vessel diameter in vivo. Histology indicated a restriction of tissue injury to the irradiated area after 1 h. Blood vessels contained aggregated red blood cells. After 24 h tissue damage occurred also outside the irradiated area and thrombus formation was visible. These results were in agreement with the mathematical calculations. In addition to initial physical effects after pulsed dye laser treatment delayed biological processes contribute significantly to the reduction of perfused blood vessels. Because of incomplete photocoagulation of smaller blood vessels (diameter 2-16 microm) a complete bleaching of PWS seems to be unlikely.

Study of patient-reported morbidity following V-beam pulsed-dye laser treatment of port wine stains

The V-beam pulsed-dye laser (PDL) (595 nm) has gained popularity in the treatment of port wine stains (PWS). It uses longer pulse durations than the standard flashlamp-pumped pulsed-dye laser (FPDL) (585 nm) and has an in-built cooling system to protect the epidermis. This should, theoretically, reduce the treatment-associated side effects, including discomfort. The aim of this questionnaire-based study was to confirm the clinical impression that V-beam PDL is well tolerated. The results were compared with a historical group of 62 PWS patients treated with FPDL. Fifty-one patients took part in the current study. Only 35.7% (vs. 81% in the historical comparison group) required topical anaesthetic prior to laser treatment. A shortening in the duration of bruising (8 vs. 10 days) and of symptoms such as burning and tightness (3 vs. 10 days) was recorded. Lifestyle change after treatment was recorded by fewer patients (39 vs. 57%). We conclude that V-beam PDL is better tolerated than FPDL when used at therapeutic levels in patients with PWS.

Evaluation of Flashlamp-Pumped Pulsed-Dye Laser (585 nm) in Nonsurgical Delay of Dorsal Rat Cutaneous Flaps

This study evaluated the efficiency of a flashlamp-pumped pulsed-dye laser operating at 585 nm in the delay of a caudally based, 10 x 3-cm dorsal rat skin flap. Two different laser treatment patterns (only longitudinal borders and the entire surface of the proposed flap) for two different fluences (6 J/cm and 8 J/cm) were compared with an acute untreated control flap as well as two surgical delay methods (incision of longitudinal borders and incision of longitudinal borders plus flap undermining). Twelve male Sprague-Dawley rats were used in each of seven groups. Two additional rats were used for histologic evaluation and two rats were used for in vivo real-time video monitoring studies. Two weeks after delay procedures, the flaps were raised and sutured on the primarily closed flap donor area. After 5 days, the length of flap survival was measured. The effects of the laser on the cutaneous vasculature and perfusion were assessed by intravenous fluorescein injection, histologic analysis, microangiography, and in vivo real-time video monitoring. No statistically significant improvement in flap survival was observed in any of the laser treatment groups. The overall findings indicate that the flashlamp-pumped pulsed-dye laser operating at 585 nm did not penetrate deep into skin and coagulate the subdermal plexus with tested laser settings and did not induce the delay phenomenon.

Treatment of linear and spider telangiectasia with an intense pulsed light source

The flashlamp-pumped pulsed dye laser (585 and 577 nm) has proved to be an effective and safe treatment option in the therapy of linear and spider facial telangiectasia. Nevertheless, the postoperative purpura, which most patients see as cosmetically disfiguring, has always been a matter of concern. To test the effectiveness and safety of an intense pulsed light source (IPLS), which emits non-coherent light adjustable within the 515-1200 nm range, in the treatment of linear and spider facial telangiectasia. One hundred and forty patients with linear and stellate facial telangiectasia were treated with an IPLS. In 94 (67.1%) the results were considered excellent (clearance of 80-100%), 43 (30.7%) showed good results (clearance of 40-80%) and in 3 patients (2.1%) the results were poor (clearance < 40%). Post-treatment side effects were minimal and well tolerated. There were no instances of scarring or other permanent side effects. Owing to the large spot size, a large area could be treated within one session. No anaesthesia was required. IPLS is a highly effective and comparably safe therapeutic alternative to the pulsed dye laser in the treatment of facial telangiectasia. The rate of cosmetically relevant side effects is considerably smaller, patient compliance is excellent and the method can easily be applied in an outpatient setting.

Clinical, Histologic, and Ultrastructural Changes after Nonablative Treatment with a 595-nm Flashlamp-Pumped Pulsed Dye Laser

BACKGROUND The flashlamp-pulsed dye laser has been used for nonablative dermal remodeling. OBJECTIVE We conducted a study analyzing the clinical, histologic, and electron microscopic findings after treatment with different flashlamp-pulsed dye laser settingss in the same subject. RESULTS Most subjects showed mild to moderate improvement after flashlamp-pulsed dye laser laser treatment. There was no statistical difference in the clinical, histologic, or electron microscopic findings with a variety of laser treatment settings. CONCLUSION Nonablative dermal remodeling can be accomplished with not only a variety of different technologies, but also with the same laser using markedly different settings.

Treatment of Facial Scarring and Ulceration Resulting from Acne Excoriée with 585-nm Pulsed Dye Laser Irradiation and Cognitive Psychotherapy

BACKGROUND Self-inflicted skin ulcers and scars are often observed in patients with compulsive skin picking. The term “neurotic excoriation” has been used to describe this condition and may or may not coexist with other true skin pathologies, such as acne. The condition poses a diagnostic and treatment challenge because patients often also have an undiagnosed underlying psychologic disorder. CASE REPORTS Two patients with numerous linear and stellate facial ulcers and hypertrophic and erythematous scars were diagnosed with acne excoriée in the setting of an obsessive-compulsive disorder linked to emotional stress and anxiety. The scars were treated with a 585-nm flashlamp-pumped pulsed dye laser using a 7-mm spot size, 1.5-msec pulse duration, and fluence range of 4.5 to 6.0 J/cm2. The patients received concomitant cognitive psychodynamic therapy to halt the cycle of impulse-driven skin picking and ulcer/scar formation. Marked clinical improvement of the scars and successful treatment of the acne excoriée were achieved with this combination approach. Relapses occurred when psychodynamic intervention was interrupted. conclusion The 585-nm flashlamp-pumped pulsed dye laser improves the appearance of hypertrophic erythematous facial scars and ulcers in patients with severe acne excoriée. Proper diagnosis of underlying impulse-control disorders and ongoing psychodynamic therapy is necessary to maintain improvement.

Role of Laser Therapy in Dermatology – Clinical Aspects

Background: Laser therapy has become an integral part of therapeutic alternatives in dermatology. Nevertheless, there are only few statistical data on the role of lasers in everyday practice of dermatological clinics. Objective: Analysis of laser patients, indications and lasers used. Methods: We analysed 10,244 patients treated with laser therapy in the Department of Dermatology at the University of Regensburg from 1992 to 2000. This figure represents 9.6 % of all patients seen during that period. Results: Vascular lesions (hemangiomas, port-wine stains, telangiectasias) represented the most common indication (more than 70%) followed by infectious disorders (mostly papillomavirus lesions) as well as the removal of hairs and tattoos. Accordingly, the most frequently used laser was the flashlamp-pumped pulsed dye laser (585 nm) followed by the argon ion, the long-pulse tunable flashlamp-pumped pulsed dye laser, the Q-switch ruby laser, and the CO₂-laser. In recent years, the percentage of indications and lasers used has changed significantly, reflecting the development of new lasers and the introduction of new indications. Conclusions: The results confirm the important role of laser therapy in dermatology.

Verrucae vulgares: flashlamp‐pumped pulsed dye laser treatment in 134 patients

Various approaches have been taken in the management of verrucae vulgares, but there is still no first-choice treatment. Thus, a study was designed to evaluate the efficacy of a flashlamp-pumped pulsed dye laser (FPDL) in the treatment of verrucae vulgares. Within 18 months, 134 patients with recalcitrant or untreated verrucae vulgares on their hands or feet, or in other sites, were exposed to a 585-nm FPDL every 3.26 weeks. The following parameters were used: energy density, 8 J/cm2; spot size, 7 mm; pulse duration, 450 micro s. Concomitant topical treatment was not recommended. Eight patients were lost to follow-up. The data of 126 patients were evaluated. Up to eight laser treatments led to total remission in 62.69% of patients and partial remission in 21.42%; 9.52% did not respond to this type of management; 6.34% of patients classified the method as too painful and withdrew after the first one or two treatments. In a median follow-up period of 5.38 months (2-16 months), one relapse occurred. FPDL is safe and effective for the removal or reduction of verrucae vulgares, and requires less patient compliance compared with other treatment options.

The flashlamp-pumped pulsed dye laser (585 nm) treatment of hypertrophic scars in Asians.

Hypertrophic scars are common and cause functional and psychologic morbidity. Various treatment modalities have been advocated in the past, but the flashlamp-pumped pulsed-dye laser-585 nm (PDL) has been shown to be effective in the treatment of a variety of traumatic and surgical scars. This study was performed to determine the effectiveness of the PDL treatment of hypertrophic scars in Asians and to elucidate possible side effects and complications. Thirteen Asian patients with 19 hypertrophic scars that had no response to conservative therapies, such as pressure therapy, intralesional corticosteroid injection, or silastic gel sheeting for more than 6 months, were treated with the PDL. Three months after the last laser treatment, improvement in the appearance, reduction in scar height, and erythema as a result of the PDL treatment were evaluated and compared with baseline values. Compared with the baseline appearance, hypertrophic scars treated with the PDL showed a satisfactory clinical improvement of 84% (16 of 19), a significant percentage of scar flattening of 58.9 +/- 22.1%, and of erythema elimination of 75.7 +/- 19.9% at month 3 after the last laser treatment. The PDL treatment of hypertrophic scars can effectively improve scar pliability and texture and decrease erythema and associated symptoms. In addition, multiple treatment sessions are suggested for achieving greater response, but lower fluences are recommended for prevention of side effects in Asians with a higher melanin content of the skin.

Efficacy of the Flashlamp-Pumped Pulsed-Dye Laser in Nonsurgical Delay of Skin Flaps

Efficacy of the Flashlamp-Pumped Pulsed-Dye Laser in Nonsurgical Delay of Skin Flaps

Efficacy of the flashlamp-pumped pulsed-dye laser in nonsurgical delay of skin flaps.

The purpose of this article was to determine the effectiveness of laser delay by use of the flashlamp-pumped pulsed-dye laser operating at a wavelength of 585 nm; to elucidate the comparable or dissimilar macroscopic, microscopic, and hemodynamic changes between laser and surgical delay methods; and to clarify the possible mechanisms underlying the delay effect of laser. A standardized caudally based random dorsal rat flap model was used in this study: Acute random skin flaps served as control subjects (group 1). Surgical delay was employed by incision of lateral longitudinal borders both without (group 2) and with (group 3) undermining, and laser delay methods were performed by laser irradiation of both lateral longitudinal borders (group 4) and the entire surface (group 5) of the proposed flap. Evaluation was done by histologic examination, India ink injection, laser Doppler perfusion imaging, and measurement of flap survival. Histologically, dilation and hypertrophy of subpapillary and subdermal vessels were evident in groups 2, 3, and 4; on the other hand, degranulation of mast cells in the vicinity of occluded vessels at the 1st hour of laser delay and a striking mast cell proliferation and degranulation in association with newly formed vessels (angiogenesis) at the 14th day of laser delay were prominent in group 5. India ink injections revealed longitudinally arranged large-caliber vessels and cross-filling between the vessels of adjacent territories in groups, 2, 3, and 4, but only small-caliber vessels in group 5. Compared with the acute flaps, both surgical and laser delay significantly increased the mean flap perfusion to the maximal levels after a 14-day delay period, and all delay procedures improved flap survival; the most significant increase in surviving area was observed in group 3, whereas the less significant increase in surviving area was in group 5. This study demonstrates that laser delay is as effective as surgical delay and that laser delay by lasering lateral borders leads to dilation and longitudinal rearrangement of the existing vessels rather than angiogenesis, whereas laser delay by lasering the entire surface results in delay effect by inducing angiogenesis due to activation and degranulation of the mast cells.

Pulsed dye laser treatment of burn scars: Alleviation or irritation?

Introduction: Burn scars are very common in both children and adults, causing great morbidity and often pose a difficult management problem. This study investigated the efficacy of the dye laser in patients with symptomatic burn scars and analysed the impact of the laser treatment on scar redness, surface texture and pruritis. Methods: Patients were placed into four groups—adult new scar ( n=8), adult old scar ( n=10), children new scar ( n=5) and children old scar ( n=15). The area of scar was divided randomly into treatment and control. Photography, histology, surface textural analysis, Vancouver and pruritis scores were made. Each selected area received three laser treatments at monthly intervals (wavelength of 585 nm with a 5 mm diameter spot at 5–6 J/cm 2). Further assessments were made at 6 and 12 months. Results: Pruritis improved significantly between treatment and control areas ( P<0.001). Vancouver scores improved in all groups and sites ( P<0.001), but not significantly between treatment and control at 6 ( P=0.876) or 12 months ( P=0.680). There was no statistical difference between treatment and control in photographic assessment at 6 ( P=0.006) or 12 months ( P=0.329) and surface profile measurements at 0 ( P=0.552), 6 ( P=0.107) or 12 months ( P=0.227). One patient withdrew from the study because of scar breakdown and three patients were lost to complete follow-up. Conclusion: The 585 nm flashlamp-pumped pulsed dye laser is an effective treatment for the intense pruritis often experienced during the healing process after a burn injury. This study has not shown other benefits, such as reduction in scar redness, height and textural improvement to be statistically significant. There is evidence that blood vessel diameters in hypertrophic scar tissue are much smaller than the vessels in port wine stains for which this laser was designed to treat. Therefore, by decreasing the pulse width, more vascular specific damage in the scar may be possible. It is likely that the beneficial effects demonstrated thus far result from changes to the chemical signals that regulate the scar growth and symptoms.

Laser treatment of rosacea

Rosacea is a common condition often resulting in persistent erythema and telangiectasia as well as rhinophyma in a number of patients. Over the last two decades lasers have been increasingly used in the treatment of these permanent changes. The literature is reviewed in terms of the different laser systems, side-effects and comparison with other surgical techniques. Laser studies on rosacea-associated telangiectasia and erythema are limited. Copper-bromide, krypton and KTP lasers have been used with good to excellent results. However, the most commonly applied system is the flash lamp-pumped pulsed dye laser. Rhinophyma can be treated with a variety of different surgical methods, including laser resurfacing. CO(2) lasers are the most widely used lasers, others are the Er:YAG and Nd:YAG lasers. Cosmetic end results are comparable to partial excision with a scalpel or electrosurgery. There does not appear to be an increased risk of infection or scarring, but the conventional surgical methods are quicker to perform and more cost effective.