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Lasers in Surgery and Medicine Oct 2023Port wine birthmarks (PWBs) are vascular malformations affecting 0.3%-0.5% of newborns with the tendency to persist into adulthood without adequate treatment of the...
Largest comparative analysis: Novel large spot size 595 nm, high-energy, pulsed dye laser reduces number of treatments for improvement of adult and pediatric port wine birthmarks.
OBJECTIVE
Port wine birthmarks (PWBs) are vascular malformations affecting 0.3%-0.5% of newborns with the tendency to persist into adulthood without adequate treatment of the heterogenous ectatic vessels. This study compares treatment outcomes and parameters of the prior generation pulsed dye laser (PPDL) and the larger spot novel generation pulsed dye laser (NPDL) to establish whether a larger spot size laser provides greater clearance with fewer treatments.
METHODS
One hundred and sixty patients were treated with either the PPDL (80 patients) and NPDL (80 patients) with retrospective review of age, body site, laser treatment parameters, number of treatments, and improvement following laser therapy.
RESULTS
Patients treated with PPDL were older on average than patients treated with NPDL (mean 24.8 ± 19.7 vs. mean 17.1± 19.3 years, p < 0.05). The majority of lesions treated with PPDL were located on the face and neck, whereas truncal and extremity sites were more frequently treated with the NPDL. Use of NPDL was associated with a mean maximum spot size of 13.1 mm and mean maximum fluence of 7.3 J/cm with pulse durations of 0.45-3 ms, whereas use of the PPDL was associated with a mean spot size of 10.8 mm and mean maximum fluence of 8.8 J/cm with pulse durations of 0.45-6 ms. Fifty percent improvement was seen with 8.8 PPDL treatments compared to 4.3 NPDL treatments (p ≤ 0.01) with no significant difference in overall mean improvement between both devices at the chosen parameters. Multiple regression analysis showed that device type, not age or lesion location, was the only statistically significant independent variable to affect the endpoint of at least 50% improvement of the lesion.
CONCLUSIONS
Use of the larger spot NPDL is associated with achieving 50% improvement with fewer treatments.
Topics: Infant, Newborn; Humans; Child; Adult; Lasers, Dye; Treatment Outcome; Laser Therapy; Port-Wine Stain; Low-Level Light Therapy
PubMed: 37293831
DOI: 10.1002/lsm.23693 -
Optics Express Jul 2023We have used photon pair correlations generated via spontaneous parametric downconversion (SPDC) to measure the fluorescence lifetime of the organic dye rhodamine 6 G,...
We have used photon pair correlations generated via spontaneous parametric downconversion (SPDC) to measure the fluorescence lifetime of the organic dye rhodamine 6 G, demonstrating that fluorescence lifetime measurements can be achieved using a continuous wave (CW) laser, without pulsed or modulated lasers. Our entangled photon method, quantum fluorescence lifetime (Q-FL) measurements, uses one photon to excite fluorescence and the resulting fluorescence photon is timed and referenced to the arrival time of the other entangled photon. Thus, we can exploit the short timescale of photon pair correlations to conduct experiments that are typically carried out with pulsed lasers and we show that the inherent timing of the photons is fast enough to resolve the nanosecond scale fluorescence lifetime of the sample. This measurement paves the way towards using the time correlations of entangled photons for fluorescence imaging; capitalizing on the presence of fast, sub-100 ps correlations that have not been demonstrated classically.
PubMed: 37710542
DOI: 10.1364/OE.494744 -
Journal of Burn Care & Research :... Mar 2024Currently, most burn models for preclinical testing are on animals. For obvious ethical, anatomical, and physiological reasons, these models could be replaced with...
Currently, most burn models for preclinical testing are on animals. For obvious ethical, anatomical, and physiological reasons, these models could be replaced with optimized ex vivo systems. The creation of a burn model on human skin using a pulsed dye laser could represent a relevant model for preclinical research. Six samples of excess human abdominal skin were obtained within one hour after surgery. Burn injuries were induced on small samples of cleaned skin using a pulsed dye laser on skin samples, at varying fluences, pulse numbers and illumination duration. In total, 70 burn injuries were performed on skin ex vivo before being histologically and dermato-pathologically analyzed. Irradiated burned skin samples were classified with a specified code representing burn degrees. Then, a selection of samples was inspected after 14 and 21 days to assess their capacity to heal spontaneously and re-epithelize. We determined the parameters of a pulsed dye laser inducing first, second, and third degree burns on human skin and with fixed parameters, especially superficial and deep second degree burns. After 21 days with the ex vivo model, neo-epidermis was formed. Our results showed that this simple, rapid, user-independent process creates reproducible and uniform burns of different, predictable degrees that are close to clinical reality. Human skin ex vivo models can be an alternative to and complete animal experimentation, particularly for preclinical large screening. This model could be used to foster the testing of new treatments on standardized degrees of burn injuries and thus improve therapeutic strategies.
Topics: Animals; Humans; Burns; Skin; Epidermis; Lasers, Dye; Wound Healing
PubMed: 37202124
DOI: 10.1093/jbcr/irad071 -
In Vivo (Athens, Greece) 2024Postoperative scar formation is inevitable, and a gold standard management has not been established to date. Due to the fact long and large scar formation occurs in...
BACKGROUND
Postoperative scar formation is inevitable, and a gold standard management has not been established to date. Due to the fact long and large scar formation occurs in reconstructive surgery, this study analyzed the relationship between various factors in patients who received breast reconstruction using latissimus dorsi (LD) flap to investigate appropriate and effective management approaches.
PATIENTS AND METHODS
Twenty-seven patients who underwent breast reconstruction between June 2014 and January 2015 received laser therapy on their LD donor site at the Kyungpook National University Chilgok Hospital. Scar evaluation was performed on both the surgical scar and intact skin on the contralateral side. Scar evaluation was conducted at five specific points, 2 cm from the midpoint of the scar on each side. Laser treatment was performed at 4-week intervals, and patients were then followed-up for 6 months. To assess scars, gross images were taken using the same settings. In addition, spectrophotometry was used for color assessment, durometer for texture and pressure evaluation, and Vernier calipers and height gauges for a more precise and objective approach.
RESULTS
The mean age of the participants was 45.7 years, and the mean body mass index was 22.1 kg/m The operator-evaluated scar scale scores were 107.2 and 97.3 in the experimental and control groups, respectively. In the patient-rated questionnaire, the scores were 62.3 and 59.4 in the experimental and control groups, respectively.
CONCLUSION
When analyzing early-stage postoperative scars based on various factors, laser therapy is considered a very useful scar management approach. Additionally, when performing reconstructive surgery, tension force is regarded as a significant factor to take into account since it affects scar widening.
Topics: Humans; Middle Aged; Cicatrix; Superficial Back Muscles; Surgical Flaps; Mammaplasty; Laser Therapy; Treatment Outcome
PubMed: 38418124
DOI: 10.21873/invivo.13509 -
Journal of Cosmetic Dermatology Sep 2023Squamous cell carcinoma (SCC) is the second most common cutaneous malignancy, after basal cell carcinoma (BCC). Photodynamic therapy (PDT) involves converting a...
Evaluating the safety and efficacy of aminolevulinic acid 20% topical solution activated by pulsed dye laser and blue light in the treatment of facial cutaneous squamous cell carcinoma in situ.
BACKGROUND
Squamous cell carcinoma (SCC) is the second most common cutaneous malignancy, after basal cell carcinoma (BCC). Photodynamic therapy (PDT) involves converting a photosensitizer to reactive oxygen intermediates, which preferentially bind to hyperproliferative tissue. The most commonly used photosensitizers are methyl aminolevulinate and aminolevulinic acid (ALA). Presently, ALA-PDT is approved in the US and Canada for the treatment of actinic keratoses on the face, scalp, and upper extremities.
AIMS
This cohort study evaluated the safety, tolerability, and efficacy of aminolevulinic acid, pulsed dye laser, and photodynamic therapy (ALA-PDL-PDT) for treatment of facial cutaneous squamous cell carcinoma in situ (isSCC).
METHODS
Twenty adult patients with biopsy-confirmed isSCC on the face were recruited. Only lesions 0.4-1.3 cm in diameter were included. Patients underwent two treatments with ALA-PDL-PDT spaced 30 days apart. The isSCC lesion was then excised 4-6 weeks following the second treatment for histopathological assessment.
RESULTS
No residual isSCC was detected in 17/20 (85%) patients. Two of the patients with residual isSCC had skip lesions present that explained the treatment failure. Excluding the patients with skip lesions, the posttreatment histological clearance rate was 17/18 (94%). Minimal side effects were reported.
LIMITATIONS
Our study was limited by small sample size and lack of long-term recurrence data.
CONCLUSIONS
The ALA-PDL-PDT protocol is a safe and well-tolerated treatment option for isSCC on the face, providing excellent cosmetic and functional results.
Topics: Adult; Humans; Aminolevulinic Acid; Photochemotherapy; Carcinoma, Squamous Cell; Cohort Studies; Lasers, Dye; Skin Neoplasms; Photosensitizing Agents; Treatment Outcome
PubMed: 37365973
DOI: 10.1111/jocd.15886 -
Journal of Cosmetic and Laser Therapy :... Nov 2023Facial and neckline telangiectasias have an underestimated yet important impact on quality of life of patients with systemic scleroderma (SSc). This monocentric,... (Clinical Trial)
Clinical Trial
Efficacy, tolerance and acceptability of pulsed dye laser on facial and neckline telangiectasias in systemic scleroderma: a prospective open-label monocentric study in 21 patients.
Facial and neckline telangiectasias have an underestimated yet important impact on quality of life of patients with systemic scleroderma (SSc). This monocentric, prospective, open-label, intra-patient comparative study was conducted in 21 consecutive patients with SSc. Patients underwent 4 sessions of PDL 8 weeks apart. A final quadruple assessment was performed by several raters 2 months after the last session, based on the following criteria: change in telangiectasia number; subjective improvement score (LINKERT scale); impact on the quality of life (QoL; SKINDEX score); visual analog pain scale; adverse effects (AEs), including treatment discontinuation for PDL-induced purpura and patient satisfaction. The mean telangiectasia number decreased by 5 (32%) at the end of the protocol. Eighteen patients (85.7%) reported an improvement or a strong improvement, versus 73.81% for the expert committee. Immediate session pain (mean = 3.4/10) was slightly less than overall pain (mean = 4.6/10). Ten patients (47%) experienced at least one AE (oozing/crusts, edema, epidermal blistering), including PDL-induced purpura in 3 patients (14%). AEs were mostly transient (<1 week) and mild (CTCAE grade 1). All QoL parameters improved after treatment, and 85% of patients were satisfied.
Topics: Humans; Lasers, Dye; Pain; Prospective Studies; Purpura; Quality of Life; Scleroderma, Systemic; Telangiectasis; Treatment Outcome
PubMed: 38373440
DOI: 10.1080/14764172.2024.2313472 -
Cold Spring Harbor Protocols Apr 2024Laser microsurgery is a robust method to ablate specific cells in the nervous system and probe the functional consequences of their loss in the animal. By introducing...
Laser microsurgery is a robust method to ablate specific cells in the nervous system and probe the functional consequences of their loss in the animal. By introducing focal lesions to small locations in the animal, laser microsurgery also enables disruptions of specific connections within neuronal circuits and the study of how the nervous system responds to precise forms of damage (for instance, damage to specific axons or dendrites, which have been found to evoke different kinds of responses in neurons). The MicroPoint laser is a pulsed dye laser that can be mounted onto any standard microscope, hence is an affordable alternative to two-photon lasers for providing high powered focal ablations. This protocol describes how to use a MicroPoint laser ablation system to induce focal injuries in larvae. This protocol guides a user who has access to a MicroPoint laser that has already been installed onto an appropriate microscope for high-resolution imaging and configured for laser ablation using Coumarin 440 dye. The protocol covers how to use the laser to carry out surgeries or ablation, how to change the laser dye and calibrate the power settings, and how to make sure the laser is properly focused. While the protocol provides an example of axotomy (axon severing) in the peripheral nervous system of larvae, use of the MicroPoint system can be adapted to other focal surgeries in other organisms.
PubMed: 38649192
DOI: 10.1101/pdb.prot108171 -
Lasers in Medical Science Nov 2023The purpose of this study is to determine the efficacy and safety of 595-nm pulsed dye laser (PDL) for port wine stains (PWS) treatment in Vietnamese patients. The study...
The purpose of this study is to determine the efficacy and safety of 595-nm pulsed dye laser (PDL) for port wine stains (PWS) treatment in Vietnamese patients. The study also analyzed the association between the response to treatment and the characteristics of patients and treatment regimens. Parallelly, the study contributed to further optimal treatment sessions for different subjects based on the data collected. One hundred twenty-five patients who underwent 595-nm PDL to treat PWS were included in the study, in which data from 124 patients was retrospectively analyzed. Data on demographic characteristics of patients, treatment regimens, and clinical improvement were collected. SPSS version 25 was used to analyze the relationship between associated factors and the response rate. The overall response rate of Vietnamese patients who had Fitzpatrick skin classification type III and IV was 73.4%. Age, gender, treatment sessions, and lesion positions were generally not associated with the response rate. The lesion grade was the sole element that affected the clinical improvement. The lesion grade 1 had the best response (100%) even after a short duration of treatment (six to ten treatments). Lesion grade 4 demanded over 16 treatments to reach > 60% of improvement. The lesion grades 1 and 2 could be blanched with regimen < 10 treatments while regimens exceeding 15 treatments should be carefully considered for lesions at grade 3 after evaluating associated conditions. Lesions at grade 4 demanded ≥ 16 treatments to reach acceptable outcomes. These results could help physicians establish a reasonable treatment strategy for patients.
Topics: Humans; Lasers, Dye; Port-Wine Stain; Retrospective Studies; Southeast Asian People
PubMed: 37934314
DOI: 10.1007/s10103-023-03926-8 -
Dermatologic Surgery : Official... Apr 2024Warts are one of the most common benign neoplasms caused by human papillomavirus infection and often pose a therapeutic challenge.
BACKGROUND
Warts are one of the most common benign neoplasms caused by human papillomavirus infection and often pose a therapeutic challenge.
OBJECTIVE
To summarize the current evidence on the safety and efficacy of laser and energy-based devices for the treatment of cutaneous verrucae.
METHODS
A comprehensive systematic review of the literature on laser and energy-based devices for the treatment of cutaneous verrucae was performed.
RESULTS
A total of 904 unique studies were identified, of which 109 were included in this review. The most commonly used lasers as a single treatment modality for verrucae included the long-pulsed Nd:Yag (n = 20) and pulsed dye (n = 18) lasers. Other modalities included the CO2 ablative laser (n = 10), photodynamic therapy (n = 11), local hyperthermia (n = 11), microwave therapy (n = 2), and nanopulse stimulation (n = 1). Other studies combined energy-based modalities with additional treatments, such as retinoids, imiquimod, and intralesional bleomycin. Overall, such devices were generally well-tolerated, with only a mild side effect profile.
CONCLUSION
Overall, the use of laser and energy-based devices is a safe and well-tolerated option for cutaneous verrucae that is relatively less invasive than surgical interventions. Future studies using more consistent outcome assessment tools will be valuable to help clinicians develop device-specific protocols and treatment regimens to ensure replicable and effective outcomes.
Topics: Humans; Treatment Outcome; Warts; Skin; Bleomycin; Hyperthermia, Induced; Lasers, Solid-State
PubMed: 38551277
DOI: 10.1097/DSS.0000000000004069 -
The Tokai Journal of Experimental and... Dec 2023Ecchymosis is a common side effect after injury and surgery. A pulsed dye laser (PDL) is the gold standard for vascular lesions and can minimize ecchymosis. Heating...
Ecchymosis is a common side effect after injury and surgery. A pulsed dye laser (PDL) is the gold standard for vascular lesions and can minimize ecchymosis. Heating induces hemoglobin modification due to oxidative and heat reactions with the formation of bilirubin and methemoglobin, resulting in color changes to brown-yellow. Therefore, downtime following cosmetic procedures can be shortened.
Topics: Humans; Ecchymosis; Lasers, Dye; Hot Temperature
PubMed: 37981852
DOI: No ID Found