Efficacy and safety comparison between pulsed dye laser and intense pulsed light configured with different wavelength bands in treating erythematotelangiectatic rosacea.

Previous clinical studies have shown that pulsed dye laser (PDL) and intense pulsed light (IPL) are effective for treating erythematotelangiectatic rosacea(ETR). This article aims to compare the efficacy and safety of PDL and IPL at three different wavelength bands (broad-band, single-narrow-band, and dual-narrow-band) in treating ETR. Sixty subjects with ETR were randomly categorized into four groups and received one of the following laser treatments: PDL (595 nm), IPL with Delicate Pulse Light (DPL, 500-600 nm), IPL with M22 590 (590-1200 nm), or IPL with M22 vascular filter (530-650 nm and 900-1200 nm). Four treatment sessions were administered at 4-week intervals, with one follow-up session 4 weeks after the final treatment. The efficacy of the four lasers was evaluated by comparing the clinical symptom score, total effective rate, VISIA red area absolute score, and RosaQoL score before and after treatment. The safety was evaluated by comparing adverse reactions such as pain, purpura, erythematous edema, and blister. All 60 subjects completed the study. Within-group effects showed that the clinical symptom score, VISIA red area absolute score, and RosaQoL score of all four groups were significantly reduced compared to before treatment (p < 0.001). Between-group effects showed no statistically significant difference among the four laser groups. Safety analysis showed that all four lasers were safe, but the incidence of blister was higher in the M22 vascular group. Nonpurpurogenic PDL, DPL, M22 590, and M22 vascular were equally effective in treating ETR and were well-tolerated. ClinicalTrial.gov Identifier: NCT05360251.

The impact of temperature on vascular function in connection with vascular laser treatment.

Pulsed dye lasers are used effectively in the treatment of psoriasis with long remission time and limited side effects. It is, however, not completely understood which biological processes underlie its favorable outcome. Pulsed dye laser treatment at 585-595 nm targets hemoglobin in the blood, inducing local hyperthermia in surrounding blood vessels and adjacent tissues. While the impact of destructive temperatures on blood vessels has been well studied, the effects of lower temperatures on the function of several cell types within the blood vessel wall and its periphery are not known. The aim of our study is to assess the functionality of isolated blood vessels after exposure to moderate hyperthermia (45 to 60°C) by evaluating the function of endothelial cells, smooth muscle cells, and vascular nerves. We measured blood vessel functionality of rat mesenteric arteries (n=19) by measuring vascular contraction and relaxation before and after heating vessels in a wire myograph. To this end, we elicited vascular contraction by addition of either high potassium solution or the thromboxane analogue U46619 to stimulate smooth muscle cells, and electrical field stimulation (EFS) to stimulate nerves. For measurement of endothelium-dependent relaxation, we used methacholine. Each vessel was exposed to one temperature in the range of 45-60°C for 30 seconds and a relative change in functional response after hyperthermia was determined by comparison with the response per stimulus before heating. Non-linear regression was used to fit our dataset to obtain the temperature needed to reduce blood vessel function by 50% (Half maximal effective temperature, ET50). Our findings demonstrate a substantial decrease in relative functional response for all three cell types following exposure to 55°C-60°C. There was no significant difference between the ET50 values of the different cell types, which was between 55.9°C and 56.9°C (P>0.05). Our data show that blood vessel functionality decreases significantly when exposed to temperatures between 55°C-60°C for 30 seconds. The results show functionality of endothelial cells, smooth muscle cells, and vascular nerves is similarly impaired. These results help to understand the biological effects of hyperthermia and may aid in tailoring laser and light strategies for selective photothermolysis that contribute to disease modification of psoriasis after pulsed dye laser treatment.

532-nm potassium titanyl-phosphate laser versus 595-nm pulsed dye laser for port-wine birthmarks: A prospective, randomized, split-side study.

BACKGROUND: Pulsed dye lasers (PDL) are currently the first-line treatment of port-wine birthmarks (PWB). Due to high maintenance costs and instable technology, alternative methods are needed. OBJECTIVES: To compare clinical outcomes of a variable-sequenced, long-pulsed 532-nm potassium titanyl-phosphate (KTP) laser and PDL on treating PWB. METHODS: A prospective, randomized, split-side study. Patients were treated with a KTP laser and PDL with 1 to 5 sessions at intervals of 6-8 weeks. A follow-up visit was scheduled 6 weeks post-treatment. Efficacy was evaluated through colorimetric analysis, area reduction measurements and clinical evaluations by two blinded investigators based on photo documentation. Subjects provided rating of pain intensity during treatment, post-treatment reactions and satisfaction. Safety was measured by adverse events. Maintenance issues of the laser systems were documented. RESULTS: A total of 35 patients (mean age 42.1 years) were enrolled. 63% were female. Patients received 2.4 (SD 1.4; 1-5) treatment sessions. Colorimetric analysis indicated a comparable clearance effect in PWB of both KTP laser and PDL. Independent investigators rated clinical appearance to be significantly improved compared to baseline. No significant difference was observed between both laser systems. Regarding post-treatment reactions, the KTP laser caused less swelling, purpura and crusts. 96% would recommend both treatment modalities. Patients were satisfied with both laser systems. During the study, PDL systems malfunctioned for 6.6 months in total. For the KTP laser, we did not observe any system failures. CONCLUSION: Our data indicate that the KTP laser of the latest generation with large-spot sizes, subpulse technology and cryogen cooling has a comparable efficacy to the PDL in treating PWB. In addition, KTP laser is associated with greater tolerability, fewer technical failures and lower repair costs. Further prospective studies are required to determine the true effectiveness of the KTP laser in PWB treatment. This study was preregistered in Clinicaltrials.gov (NCT05771298).

Modeling pulsed dye laser treatment of psoriatic plaques by combining numerical methods and image-derived lesion morphologies.

OBJECTIVES: Knowledge of the physical effects of pulsed dye laser (PDL) treatment of psoriatic lesions is essential in unraveling the remedial mechanisms of this treatment and hence also in maximizing in its disease-modifying potential. Therefore, the main objective of this study was to provide estimates of these physical effects (for laser wavelengths of 585 and 595 nm), with the aim of identifying pathogenic processes that may be affected by these conditions. METHODS: We modeled the laser light propagation and subsequent photothermal heating by numerically solving the transient diffusion and heat equations simultaneously. To this end, we used the finite element method in conjunction with an image-derived psoriatic lesion morphology (which was defined by segmenting blood vessels from a confocal microscopy image of a fluorescently labeled section of a 3 mm punch biopsy of a psoriatic lesion). The resulting predictions of the generated temperature field within the lesion were then used to assess the possibility of stalling or arresting some suspected pathogenic processes. RESULTS: According to our results, it is conceivable that perivascular nerves are thermally denatured, as almost all locations that reach 60°C were found to be within 18 µm (at 585 nm) and 11 µm (at 595 nm) of a blood vessel wall. Furthermore, activation of TRPV1 and TRPV2 channels in perivascular neuronal and immune cells is highly likely, since a critical temperature of 43°C is generated at locations within up to 350 µm of a vessel wall (at both wavelengths) and sustained for up to 700 ms (at 585 nm) and 40 ms (at 595 nm), while a critical temperature of 52°C is reached by locations within 80 µm (at 585 nm) and 30 µm (at 595 nm) of a vessel wall and sustained for up to 100 ms (at 585 nm) and 30 ms (at 595 nm). Finally, we found that the blood vessel coagulation-inducing temperature of 70°C is sustained in the vascular epithelium for up to 19 and 5 ms at 585 and 595 nm, respectively, rendering partial or total loss of vascular functionality a distinct possibility. CONCLUSIONS: The presented approach constitutes a useful tool to provide realistic estimates of the photothermal effects of PDL treatment of psoriatic plaques (as well as other selective photothermolysis-based treatments), yielding information that is essential in guiding future experimental studies toward unraveling the remedial mechanisms of these treatments.

Fragile hands: targeting nonmelanoma skin cancer on older hands using 595 nm pulsed dye laser.

PURPOSE: The mainstay of treatment for nonmelanoma skin cancer (NMSC) on thin skin remains surgical, but procedures on older hands may be complicated by skin fragility and dermal atrophy. Used without cooling, 595 nm (nm) pulsed dye laser (PDL) has the capability of destroying NMSC through nonspecific thermal necrosis. The purpose of this study was to understand recurrence of NMSC on dorsal hands of older patients after one or two treatments using 595 nm PDL. METHODS: A retrospective chart review identified 147 cases of NMSC located on the dorsal hands treated with 595 nm PDL. Cases of basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs) were included. All patients received one to two treatments with PDL. The primary outcome was the recurrence of carcinoma. RESULTS: Among NMSC cases treated with PDL, recurrence occurred in 12 patients (8.2%). No cases of BCC recurred during the study period. Recurrence of SCC was 4.7% for SCC in situ and 10.4% recurrence for invasive SCC (p = 0.34). Among 71 patients treated once, recurrence occurred in 10 patients (14.1%), and among 76 cases treated twice, recurrence occurred in 2 patients (2.6%, p = 0.01). CONCLUSION: Two treatments of PDL for NMSC on the dorsal hands of older patients was well tolerated, had low recurrence, and seemed more effective than one treatment.

Current clinical evidence is insufficient to support HMME-PDT as the first choice of treatment for young children with port wine birthmarks.

BACKGROUND: Port wine birthmark (PWB) is a congenital vascular malformation of the skin. Pulsed dye laser (PDL) is the "gold standard" for the treatment of PWB globally. Hematoporphyrin monomethyl ether (HMME or hemoporfin)-mediated photodynamic therapy (HMME-PDT) has emerged as the first choice for PWB treatment, particularly for young children, in many major hospitals in China during the past several decades. AIM: To evaluate whether HMME-PDT is superior to PDL by comparing the clinical efficacies of both modalities. METHOD: PubMed records were searched for all relevant studies of PWB treatment using PDL (1988-2023) or HMME-PDT (2007-2023). Patient characteristics and clinical efficacies were extracted. Studies with a quartile percentage clearance or similar scale were included. A mean color clearance index (CI) per study was calculated and compared among groups. An overall CI (C0), with data weighted by cohort size, was used to evaluate the final efficacy for each modality. RESULT: A total of 18 HMME-PDT studies with 3910 patients in China were eligible for inclusion in this analysis. Similarly, 40 PDL studies with 5094 patients from nine different countries were eligible for inclusion in this analysis. Over 58% of patients in the HMME-PDT studies were minors (<18 years old). A significant portion (21.3%) were young children (<3 years old). Similarly, 33.2% of patients in the PDL studies were minors. A small proportion (9.3%) was young children. The overall clearance rates for PDL were slightly, but not significantly, higher than those for HMME-PDT in cohorts with patients of all ages (C0, 0.54 vs. 0.48, p = 0.733), subpopulations with only minors (C0, 0.54 vs. 0.46, p = 0.714), and young children (C0, 0.67 vs. 0.50, p = 0.081). Regrettably, there was a lack of long-term data on follow-up evaluations for efficacy and impact of HMME-PDT on young children in general, and central nervous system development in particular, because their blood-brain barriers have a greater permeability as compared to adults. CONCLUSION: PDL shows overall albeit insignificantly higher clearance rates than HMME-PDT in patients of all ages; particularly statistical significance is nearly achieved in young children. Collectively, current evidence is insufficient to support HMME-PDT as the first choice of treatment of PWBs in young children given: (1) overall inferior efficacy as compared to PDL; (2) risk of off-target exposure to meningeal vasculature during the procedure; (3) administration of steriods for mitigation of side effects; -and (4) lack of long-term data on the potential impact of HMME on central nervous system development in young children.

Treatment of erythematous acne scars using 595-nm pulsed dye laser combined with 1565-nm ResurFX nonablative fractional laser.

BACKGROUND: Acne vulgaris is a common inflammatory disease associated with various sequelae after skin lesion remission. Acne erythema has been considered simple erythema or a vascular lesion; however, because the understanding of this disease has improved, acne erythema is currently considered an early scar with erythematous components. AIMS: This study evaluated the efficacy of using both a 595-nm pulsed dye laser (PDL) and 1565-nm nonablative fractional laser (NAFL) for the treatment of erythematous scars caused by acne. METHODS: Ninety patients with acne scars were equally randomized to two groups. Group A (n = 45) received treatment with the NAFL. Group B (n = 45) received treatment with the PDL and NAFL. Each patient underwent one treatment session and 4 weeks of follow-up. RESULTS: Qualitative (χ2 = 12.415; p < 0.05) and quantitative (t = 2.675; p < 0.05) scores of Groups A and B were determined using a global scarring grading system and exhibited statistically significant differences. The quantitative score of Group A was higher than that of Group B (6.67 ± 3.46 vs. 4.98 ± 2.44). The erythema areas of the groups differed significantly after treatment, with Group B exhibiting more notable score improvements (5.00 [3.10, 7.10] vs. 2.80 [1.65, 4.60]; Z = 3.072; p < 0.05). The erythema regression rate of Group B (88.9%) was significantly higher than that of Group A (66.7%) (χ2 = 20.295; p < 0.001). Adverse events, including redness and swelling (86.6%), scabbing (78.8%), and purpura (36.6%), occurred within 7 days for 86.6% of patients. CONCLUSIONS: The combined use of the PDL and NAFL is safe and effective for erythematous acne scars.

The efficacy, satisfaction, and safety of carbon dioxide (CO2) fractional laser in combination with pulsed dye laser (PDL) versus each one alone in the treatment of hypertrophic burn scars: a single-blinded randomized controlled trial.

The tendency to use less-invasive laser-based methods with far more obvious effectiveness has been taken into consideration today for improvement of burning scars. The present study thus aimed to assess the efficacy of two laser-based techniques including pulsed dye laser (PDL) and ablative fractional CO2 laser (AFCL) and its combination on improving different aspects of burning scars regardless of the types of scar as hypertrophic or keloid scars. This randomized single-blinded clinical trial was performed on patients suffering hypertrophic or keloid burning scars. The patients were randomly assigned into three groups scheduling for treatment with PDL alone, AFCL alone, or its combination. All patients were visited before and 40 days after the last treatment session, and their scars were assessed. In all groups, significant improvement was revealed in the Vancouver scar scale (VSS) score, the color of scar, vascular bed in the scar, the and height of scar and its pliability; however, the improvement in each item was more highlighted in the group receiving a combination therapy with PDL and AFCL techniques. In this regard, the highest improvement was found in vascular bed and pliability in the combination therapy group as compared to other groups. Although the superiority of the combined group was not statistically significant, due to the high percentage of improvement in total VSS and most of its indicators, it can be clinically significant. The efficacy of the treatment protocols was different considering subgroups of mature and immature scars (less than 1 year), so that more improvement in pliability of scar, vascularity, and color of scar was found in the group scheduling for PDL + AFCL as compared to those who were treated with PDL alone in immature scar group but not in mature scar group. Combined treatment can be much more effective in improving the appearance and pathological characteristics of scars than each individual treatment. This effectiveness can be seen mainly in immature scars.

The Effectiveness of 595-nm Pulsed Dye Laser for the Treatment of Bilateral Cleft-Lip Scars in Asian Patients: A 6-Month Prospective, Randomized, Self-Controlled Trial.

Objective: This study is the first prospective within-patient self-controlled research seeking to investigate the safety and efficacy of 595 nm pulsed-dye laser (PDL) for the treatment of cleft-lip scars. Approach: This prospective, randomized, self-controlled study is based on the clinical records of the patients who received laser-assisted treatment due to bilateral cleft-lip scars. The bilateral scars were randomly assigned to the 595 nm PDL group with five consecutive sessions at 2-week intervals or control group in a blinded manner of evaluators, with subsequent follow-up for 6 months after the final treatment. Clinical efficacy and safety outcomes were evaluated by Vancouver Scar Scale (VSS), Patient Scar Assessment Questionnaire (PSAQ), and other objective evaluations. Results: A total of 18 patients were included. The 595 nm PDL-treated sides showed statistically significant improvement in VSS after treatment at follow-up compared with the baseline (p < 0.05). Interestingly, the 595 nm-PDL-treated side achieved significantly better improvement in scar pigmentation and pliability (p < 0.05). Though there was statistically significant difference between two groups (p < 0.05), the gap in overall PSAQ is not obvious. And comparison by area and coloring evaluation (E/M index) also suggests that the responses of scars to treatment by PDL were slightly improved (p < 0.05). Innovation and Conclusion: It is the first time to apply the 595nm PDL for cleft-lip scars. It would be a better choice for the early treatment of red scar with proliferative tendency after cleft-lip surgery.

Effect of Laser and Energy-based Device Therapies to Minimize Surgical Scar Formation: A Systematic Review and Network Meta-analysis.

Utilization of lasers and energy-based devices for surgical scar minimization has been substantially evaluated in placebo-controlled trials. The aim of this study was to compare reported measures of efficacy of lasers and energy-based devices in clinical trials in preventing surgical scar formation in a systematic review and network meta-analyses. Five electronic databases, PubMed, Scopus, Embase, ClinicalTrials.gov, and the Cochrane Library, were searched to retrieve relevant articles. The search was limited to randomized controlled trials that reported on clinical outcomes of surgical scars with treatment initiation no later than 6 months after surgery and a follow-up period of at least 3 months. A total of 18 randomized controlled trials involving 482 participants and 671 postsurgical wounds were included in the network meta-analyses. The results showed that the most efficacious treatments were achieved using low-level laser therapy) (weighted mean difference -3.78; 95% confidence interval (95% CI) -6.32, -1.24) and pulsed dye laser (weighted mean difference -2.46; 95% CI -4.53, -0.38). Nevertheless, low-level laser therapy and pulsed dye laser demonstrated comparable outcomes in surgical scar minimization (weighted mean difference -1.32, 95% CI -3.53, 0.89). The findings of this network meta-analyses suggest that low-level laser therapy and pulsed dye laser are both effective treatments for minimization of scar formation following primary closure of surgical wounds with comparable treatment outcomes.

Comparative Treatment of Mucocutaneous Lesions in Hereditary Haemorrhagic Telangiectasia Patients With Dual Sequential Pulsed Dye Laser and Neodymium: Yttrium-Aluminium-Garnet Versus Neodymium: Yttrium-Aluminium-Garnet Laser Alone: A Double-Blind Randomized Controlled Study With Quality-of-Life Evaluation. / [Artículo traducido] Tratamiento comparativo de lesiones mucocutáneas en pacientes con telangiectasia hemorrágica hereditaria con láser dual secuencial de colorante pulsado y neodimio: itrio-aluminio-granate versus neodimio: itrio-aluminio-granate solo: un estudio controlado aleatorizado doble ciego con evaluación de la calidad de vida.

BACKGROUND: Hereditary haemorrhagic telangiectasia (HHT) is characterized by the presence of telangiectases and larger arteriovenous malformations in different organs. Mucocutaneous telangiectases can bleed and become an aesthetic concern, impairing quality of life (QoL). However, the best treatment approach has not been defined yet. OBJECTIVE: To evaluate the efficacy and safety of dual wavelength sequential 595/1064nm laser (DWSL) compared to 1064nm laser (Nd:YAG) alone. Secondarily, to evaluate QoL impairment in HHT patients, and its improvement with laser therapy. METHODS: A comparative randomized split-body double-blinded prospective study (DWSL vs Nd:YAG). Demographic, clinical and treatment characteristics were recorded. The severity and degree of improvement were evaluated by three blinded examiners who scored pre-treatment and post-treatment pictures on a 5-point scale. Patients fulfilled Skindex-29 and FACE-Q® tests and assessed procedure-associated pain and patient satisfaction. RESULTS: 111 treatment areas (55 treated with DWSL and 56 with Nd:YAG) from 26 patients were analyzed. The median number of laser sessions was 2 (interquartile range [IQR] 2-4; mean 2.90 vs 2.88, respectively). The median improvement score, irrespective of location, was significantly higher for Nd:YAG compared to DWSL: 3 (IQR 2-3; mean 2.61) vs 2 (IQR 2-3; mean 2.32), p=0.031. Both FACE-Q index and Skindex-29 test results improved significantly (p<0.001), and 92.4% patients reported a high degree of satisfaction (≥8). No severe adverse events were reported. CONCLUSIONS: DWSL and Nd:YAG laser are convenient, safe and effective treatment options for mucocutaneous telangiectases in HHT patients. However, Nd:YAG delivered better results with better tolerability. QoL was significantly improved by both treatments.

Successful treatment of xanthoma disseminatum with pulsed dye laser: A case report.

Xanthoma disseminatum is a rare form of non-Langerhans cell histiocytosis with limited treatment options due to its unknown aetiology and diffuse skin lesions. This case report presents the successful treatment of a 31-year-old male with severe pan-facial xanthoma disseminatum lesions following a facial burn and traumatic brain injury resulting from a car accident. After 5 sessions of monthly pulsed dye laser treatment, there was a clinically significant reduction in the lesions. Over the course of 3 years, the patient underwent a series of monthly pulsed dye laser treatments, and the lesions were almost cleared. These findings suggest that pulsed dye laser therapy may offer an effective treatment option for managing xanthoma disseminatum. This is the first report on use of the pulsed dye laser for treatment of xanthoma disseminatum.

A 595 nm pulsed dye laser as an adjuvant intervention for post-comedone extraction erythema and comedone reduction: A randomized, split-face controlled trial.

BACKGROUND: Comedone extraction provides greater satisfaction for acne treatment than conventional treatment alone; however, post-comedone extraction erythema (PCEE) remains a concern for patients. OBJECTIVES: To evaluate the efficacy of pulsed-dye laser (PDL) in PCEE and comedone reduction. METHODS: Mild-to-moderate acne patients were randomly allocated in split-face fashion. Three comedones were extracted on each facial side. On the PDL-treated side, 595-nm PDL was delivered to the entire side with an additional shot on three comedone-extracted sites. Erythema index (EI) and total acne lesion counts (TALC) were evaluated at baseline, week 2 and 4. The comprehensive acne severity scale (CASS) was assessed by three blinded independent pediatric dermatologists. Participant satisfaction surveys were completed at the end of the study. RESULTS: Thirty-five participants (age 12.9-24.2 years) showed no differences in the EI and TALC at baseline on both sides. At weeks 2 and 4, the EI on the PDL-treated side was significantly lower (p < 0.001) with a greater EI reduction (p < 0.001) when compared to the control side regardless of gender and menstruation. There was significantly lower TALC on the PDL-treated side at week 2 (p < 0.001) and week 4 (p = 0.02). No complications were noted with high participant satisfaction reported (median 8; IQR 7-9). PDL remained significantly associated with EI improvements after controlling for gender, menstruation cycle, and examination stress. CONCLUSION: PDL can be an adjunctive intervention for the treatment of PCEE and comedone reduction due to its effectiveness and high participant satisfaction.

Pulsed dye laser and adjuvant topical therapies for the treatment of port-wine stains: A systematic review.

OBJECTIVES: The current gold standard treatment for port-wine stains (PWS) is pulsed dye laser (PDL). However, multiple treatment sessions may be necessary and complete resolution is often not achieved. Neoangiogenesis can occur soon after treatment and is thought to be a major factor contributing to treatment failure. Adjuvant antiangiogenic topical therapies may therefore improve the efficacy of pulsed dye laser treatment of port-wine stains. MATERIAL AND METHODS: Following PRISMA guidelines, we searched PubMed, Embase, Web of Science, and clinicaltrials.gov using "port-wine stain," "nevus flammeus," "capillary malformation," "sturge weber," and "pulsed dye laser" as keywords and medical subject heading (MeSH) terms. Articles were included if they (1) were a randomized controlled trial (RCT); (2) studied patients with PWS; and (3) investigated topical adjuvant therapies with PDL. Bias was assessed using the Critical Appraisal Skills Programme (CASP) Randomized Controlled Trial Standard Checklist. RESULTS: 1835 studies were identified, with six studies meeting inclusion criteria. The total number of patients studied was 103 (range: 9-23), with 8-36 week follow-up. The average age ranged from 11 to 33.5 years old. Three studies examined adjuvant topical sirolimus (n = 52), two examined timolol (n = 29), and one studied imiquimod (n = 22). Two of three RCTs reported no improvement through colorimetric analysis with topical sirolimus; however, one of these studies did show a significant improvement through Investigator Global Assessment (IGA) score. The last sirolimus study showed significant improvement through digital photographic image scoring (DPIA). Studies examining topical timolol reported no change in PWS appearance compared to placebo. The addition of 5% adjuvant imiquimod cream did lead to significant improvement. A variety of outcome measures were used. Imiquimod and sirolimus led to mild cutaneous adverse events, while timolol caused no side effects. None of the adverse events led to treatment discontinuation. Study quality was moderate in three, high in two, and low in one. CONCLUSION: The efficacy of adjuvant topical therapy was unclear. Limitations included variation in concentration and duration of adjuvant therapies, differences in follow-up time, and inconsistent outcome measure reporting. Given their potential clinical promise, larger prospective studies examining topical adjuvant therapies should be considered.

Delayed ulceration following combination pulse dye laser and topical sirolimus treatment for port wine birthmarks: A case series.

Port wine birthmarks (PWB) are capillary vascular malformations within the papillary and reticular dermis, most commonly occurring on the head and neck and may darken and thicken with age. Pulsed dye laser (PDL) is the gold standard of treatment for PWB as it selectively targets involved vessels. Sirolimus is a macrolide antibiotic that selectively inhibits mammalian target of rapamycin, thereby suppressing the angiogenesis pathways that can be activated by PDL. Sirolimus and PDL may be used together to treat PWB. We present a case series describing three cases of delayed ulceration and systemic sirolimus absorption following combination therapy, highlighting a potential complication and patient safety concern.

A New Ex Vivo Human Skin Burn Model.

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.