Laser Ablation Therapy Research Articles

Impact of Fractional Ablative Laser Therapy on Function, Symptoms, and Quality of Life in the Management of Traumatic Scars: A Review

ABSTRACTObjectivesA substantial and expanding body of literature addresses the safety and efficacy of fractional ablative laser therapy for traumatic scarring resulting from burns and other trauma. However, available scar research commonly employs standardized assessment scales that generally do not directly address the impact on function and overall quality of life. Unlike past reviews, this manuscript will explore available evidence with a focus explicitly on function and quality of life (QoL) outcomes and de‐emphasize surrogate outcome measures that rely primarily on visual characteristics.MethodsThrough literature review conducted up to January 2024, the authors examined relevant studies focusing on function and quality of life outcomes in traumatic and burn scar management with fractional ablative laser therapy. PubMed, EMBASE, MEDLINE, and Cochrane Library were utilized as primary databases. Reference lists were secondarily reviewed to supplement the literature review process. Studies that did not highlight functional or QoL endpoints or were not in the English language were excluded.ResultsThe reviewed studies demonstrated that fractional ablative therapy led to consistent significant and meaningful improvements in functional outcomes, relief from pruritus and pain, and overall enhancements in quality of life for patients with traumatic scarring. Adverse events associated with fractional ablative therapy were infrequent and generally of mild severity, indicating a favorable safety profile.ConclusionsThe findings from this literature review document ample existing evidence supporting the efficacy and safety of fractional ablative therapy to enhance function, mobility, reduce pruritus and pain, and improve overall QoL. Fractional ablative laser therapy should be integrated more widely into standard management protocols. Given the previous reliance on standardized scar assessment tools that heavily integrate visual characteristics, future studies should prioritize functional and QoL outcomes to further advance scar management protocols and optimize patient care.

Long-term remission of Hailey-Hailey disease by Er:YAG ablative laser therapy.

Hailey-Hailey disease (HHD) is a rare genetic therapy-resistant blistering disease with great disease burden. Treatment is currently focused on symptomatic relief. Er:YAG ablative laser therapy is a therapeutic modality with promising results, though evidence is currently scarce. To analyse the effect of Er:YAG ablative laser therapy on clinical remission of erosive plaques in HHD and on patient's quality of life (QoL). In this observational study eight patients were included and 77 erosive plaques were treated once only by Er:YAG laser and assessed for clinical remission. QoL was evaluated by obtaining Skindex-29 and DLQI questionnaires before laser therapy, 6 weeks and 3 years after laser therapy. Skin biopsies were taken to evaluate the depth of laser ablation. The intercellular distance between keratinocytes, the number of desmosomes and intermediate filament distribution were studied by electron microscopy before and after laser therapy and in clinically uninvolved skin and were compared to subjects without HHD. One single Er:YAG laser ablation to mid-dermis resulted in complete remission of 97.4% of HHD plaques (75/77) after median 38 months (range 7-63 months) and significantly improved QoL. Laser therapy restored the number of desmosomes, decreased intercellular distance and diminished perinuclear retraction of keratin filaments to a level comparable to the patient's clinically uninvolved skin. After laser ablation, the skin showed significantly fewer ultrastructural aberrations compared to the patient's clinically uninvolved skin and rather resembled the skin of healthy control individuals. One single Er:YAG laser treatment resulted in long-term remission of HHD and significantly improved QoL. Our findings support a greater role for ablative laser surgery in the management of this recalcitrant disorder.

Comparison of Low-dose Diluted Hyperbaric Bupivacaine and Standard Hyperbaric Bupivacaine in Subarachnoid Block for Ambulatory Endovenous Laser Ablation of Varicose Vein: A Randomized Controlled Trial

Abstract Background: Low-dose spinal anesthesia represents a highly coveted anesthetic technique for patients undergoing endovenous laser ablation of varicose veins in a day-care setting, given its prompt onset, reliable anesthesia, brief turnover time, and cost-effectiveness. Given that intense motor block is not required for this procedure, this trial compared the efficacy of low-dose diluted hyperbaric bupivacaine with standard hyperbaric bupivacaine in the subarachnoid block for endovenous laser ablation of varicose veins. Methodology: A prospective, randomized controlled trial at a tertiary care hospital, Tamil Nadu, South India. Sixty individuals with varicose veins requiring endovenous laser ablation surgery were split at random into two groups. Group A (n = 30) got 0.5% hyperbaric bupivacaine 10 mg (2 ml), Group B (n = 30) got diluted hyperbaric bupivacaine 5 mg (1 ml of 0.5% hyperbaric bupivacaine diluted with an equivalent volume of normal saline) intrathecally. This study evaluated the time to surgical readiness, peak sensory block level, motor block grade, sensory block level at the completion of surgery, duration of motor and sensory blocks, and timing of discharge. Results: The median peak sensory block level for Group A was T6 (T8–T6), whereas for Group B it was T8 (T10–T6), with a P = 0.03. At the conclusion of surgery, the median sensory block level was T6 (T6–T8) for Group A and T8 (T7–T10) for Group B. No patients in either group needed a rescue analgesic. The average timing of discharge for Group B was shorter (P = 0.00002). Conclusion: For patients receiving endovenous laser ablation therapy for varicose veins, subarachnoid blockade with low-dose diluted hyperbaric bupivacaine (5 mg) offers an effective anesthesia, the best recovery profile, and early hospital discharge.

Timing of Laser Intervention on Facial Scars: A 3D Imaging and Scar Scale Analysis in a Retrospective Study.

Scars resulting from injuries or surgical procedures often present both physical and aesthetic challenges. Recent studies have indicated promising results in improving postoperative scar outcomes through the combined use of specific laser technologies. Nevertheless, there remains a crucial need for further exploration to ascertain the optimal timing for initiating such treatments. In this retrospective investigation, a cohort of 47 adult patients who did not require hospitalization was analyzed. These patients were divided into two distinct groups: Group A, which received intervention beginning 2 weeks after their respective operations, and Group B, which commenced intervention 4 weeks postoperation. Each group underwent a comprehensive treatment protocol consisting of five laser sessions. Initially, patients underwent three sessions of V-beam pulsed-dye laser (PDL) therapy followed by two sessions of ablative fractional CO2 laser (AFL) therapy. Evaluation of outcomes was conducted using advanced imaging techniques such as Antera 3D imaging, in conjunction with established scar assessment tools including the Vancouver Scar Scale (VSS) and the University of North Carolina "4P" Scar Scale (UNC4P). All patients successfully completed the full course of five treatment sessions, with no dropouts and no reported adverse events. Baseline cosmetic assessments of scars were equivalent across both groups. In Group A, the mean VSS scores decreased from 7.04 before treatment to 5.29 at 3 months posttreatment and further to 4.33 at 6 months posttreatment. Meanwhile, in Group B, scores decreased from 7.52 to 6.83 at 3 months and 6.17 at 6 months. There were no statistically significant differences in baseline VSS scores between the two groups (p = 0.34). At both the 3- and 6-month follow-up points, mean VSS scores were significantly lower in Group A compared to Group B (p < 0.05). Similar trends were observed in UNC4P scores. Statistically significant differences were noted across all time points (baseline, 3 months, and 6 months posttreatment) for both VSS and UNC4P scores (p < 0.05). Subset analysis revealed greater improvements in texture and depression volume at 3 months posttreatment, while improvements in depression area, depth, elevation variation, and area were more pronounced at the 6-month mark. Early intervention using the combined 595-nm pulse dye laser and CO2 ablative fractional laser (AFL) 2- and 4-weeks post-surgery proves to be an effective and safe method for improving scar outcomes, particularly for facial surgical scars when treatment starts 2 weeks after surgery. However, further research is needed to refine our understanding and address potential study limitations.

Stealth Autoguide as Robotic Holder for Cranial Endoscopic Surgery: Technical Note and Proof of Concept

The Stealth Autoguide (Medtronic, Minneapolis, USA) is a robotic auto-targeting device for stereotactic brain biopsy, placement of stereoelectroencephalography electrodes, and laser ablation therapy. This paper evaluates its off-label application as robotic endoscope holder in transnasal and intraventricular neurosurgery. The potential to enhance stability, reduce manual adjustments, and improve surgical precision is discussed, alongside cost-effectiveness and feasibility. Patients who underwent endoscopic endonasal, transventricular, and microsurgical endoscopic-assisted surgeries using the Stealth Autoguide as robotic holder from August 2023 to March 2024 were included. Surgical data and surgeons' remarks on advantages, disadvantages and limitations of the technique were collected. In this preliminary experience, Stealth Autoguide has proven safe and effective for several approaches. It was successfully used for patients with sellar, parasellar and suprasellar lesions. Moreover, the holder was employed in a third ventriculocisternostomy, a septostomy, and a removal of intraventricular lesion. Finally, the Autoguide has been a useful holder for the endoscope after gross total microsurgical excision of a tumor: the robot aligned the endoscope to the chosen trajectory and allowed the surgeon to "look around the corner" and confirm the extent of resection. No complications occurred in the treated cases, and the system provided great stability and usefulness throughout the surgeries. This experience proves that the Stealth Autoguide can be safely and effectively used as a robotic support for endoscopic procedures. This device ensures precise positioning and manipulation of neuroendoscopes, facilitating visualization and targeting of the desired area. Further researches are needed to verify applications and limitations.

Efficacy of a Combination Treatment of Ablative Fractional Carbon Dioxide Laser Therapy and Recombinant Human Epidermal Growth Factor for Atrophic Acne Scars.

Atrophic acne scars (AAS) are disfiguring and permanent changes caused by inflammatory acne. Fractional carbon dioxide is a common ablative device used to treat this condition. However, issues such as unclear effectiveness, frequent treatments, and potential side effects exist. In recent years, recombinant human epidermal growth factor (rhEGF) has also been frequently reported for its application in the treatment of acne scars. To explore the potential synergistic effect of fractional carbon dioxide laser combined with rhEGF in AAS treatment. We enrolled 15 patients with AAS. They received fractional carbon dioxide laser treatment and were then randomly assigned to receive either rhEGF or a placebo on one side of the face. The procedure was repeated three times, and the results were evaluated using the échelle d'évaluation clinique des cicatrices d'acné (ECCA) score and analyzed using the CBS camera system, 3D analysis (3DMD). Reflectance confocal microscopy (RCM) examination was also conducted. Both sides exhibited significant improvement in the appearance of the acne scars after treatment, as confirmed by the ECCA score, 3DMD data, and CBS texture score. On the rhEGF-treated side, the pore number and epidermal pigment area significantly improved as compared to the control side, whereas no significant differences were observed in the other data. Under RCM, a significant increase in epidermal thickness and appearance of reticular collagen fibers in the dermal layer after treatment was observed. Compared to the sole use of laser, the combination of fractional carbon dioxide laser and rhEGF does not significantly enhance scar therapeutic effects. However, it does shorten the recovery period after laser treatment and improves the pore appearance.

Follicular unit extraction combined with fractional carbon dioxide laser therapy for post-traumatic eyebrow scar with defects: A prospective and comparative study.

Eyebrows play a crucial role in the human body. While Follicular Unit Extraction (FUE) is a widely utilized and highly effective treatment for typical eyebrow deficiencies, it may not yield satisfactory outcomes for patients with post-traumatic eyebrow scars and defects. A prospective comparative clinical study was conducted to explore the treatment outcomes of post-traumatic eyebrow scars accompanied by defects using a combination of ablative fractional CO2 laser therapy with FUE. Between January 2019 and January 2023, we enrolled 30 patients with post-traumatic eyebrow scars and accompanying eyebrow defects, randomly assigning them to experimental and control groups. Patients in the control group received FUE treatment exclusively, whereas patients in the experimental group underwent CO2 fractional laser therapy on the eyebrow scars prior to FUE treatment. Alongside the patients' baseline data and the quantity of transplanted follicular units during surgery, we will compare the follicular survival rates between the two groups at 6 and 12 months post-treatment. Prior to FUE, there were no notable variances in baseline data between the two-patient groups. At 6 and 12 months postoperatively, the follicular survival rate in the experimental group was significantly higher compared to the control group. Additionally, patients in the control group were more prone to experiencing postoperative asymmetry between their eyebrows and developing curly hair. For patients with post-traumatic eyebrow scars accompanied by eyebrow defects, we applied ablative fractional CO2 laser therapy in combination with FUE treatment. This approach not only resulted in a higher follicular survival rate postoperatively but also led to the achievement of a well-defined eyebrow shape.

Prophylactic Antibiotics are Unnecessary for Routine CO2 Laser Burn Scar Treatment.

CO2 ablative fractional laser (CO2 AFL) therapy is a safe and effective procedure when used in the treatment of hypertrophic scars for burn patients. It has a high patient satisfaction rate and a minimal side effect profile, typically consisting of postoperative pain, irritation, surgical site inflammation, and, in rare cases, infection. Although prophylactic antibiotics have historically been recommended, there is a paucity of literature on the topic and recent studies indicate that they may be unnecessary in routine cases. In this retrospective, single center descriptive study, 230 cases in patients with hypertrophic burn scars treated with CO2 AFL therapy were compared. 28 cases were with the use of prophylactic antibiotics and 201 cases were without the use of prophylactic antibiotics. We found that there was no significant association between the use of antibiotics and the prevention of topical skin infection in cases treated with CO2 AFL therapy (p=1). Therefore, we conclude that the omission of prophylactic antibiotics is not associated with an increased risk of infection and recommend that prophylactic antibiotics should not be indicated in the setting of routine CO2 AFL therapy for patients with hypertrophic burn scars.

СОВРЕМЕННАЯ ТАКТИКА ХИРУРГИЧЕСКОГО ЛЕЧЕНИЯ БОЛЬНЫХ С ВАРИКОЗНОЙ БОЛЕЗНЬЮ НИЖНИХ КОНЕЧНОСТЕЙ

Varicose veins are a very popular disease. It is observed in 10–15% of men and 20–35% of women and is often accompanied by long-term incapacity and subsequent disability of the patient. That’s why it’s not surprising that endovenosus laser ablation therapy (EVLT) is replacing surgery as the main treatment for varicose veins. Currently, laser radiation with wavelengths in the λ range from 0.45 to 2 is used for EVLT. A positive treatment result was achieved at all wavelengths that were used. The resulting differences in clinical applications in terms of pain levels, complications, and postoperative healing were rates largely subjective, leading to controversy regarding the choice of the most effective method. This was facilitated by the evolution of interpretations of the processes occurring during EVLT, which, from the authors’ point of view, is useful for their understanding. Endovasal methods have been proven to be cost-effective and safe and can be performed under local anesthesia on an outpatient basis. To date, this technique has become quite widespread in vascular surgery. This paper provides a review of the literature on the prevalence and pathophysiology of varicose veins of the lower extremities, the achievements of endovasal methods of treating varicose veins of the lower extremities, and studied modern methods of surgical correction of varicose veins. We analyzed and described the main issues related to endovenous techniques for obliterating varicose veins. Conducted on 20 case histories of patients with venous insufficiency of the lower extremities, operated on at the CHU “KB “RZD-Medicine” named after. N.A. Semashko” comparative analysis of modern surgical methods for the treatment of varicose veins of the lower extremities. The operation was performed on one lower limb in 18 patients, and on two lower limbs in 2 people. All patients underwent endovasal laser coagulation (EVLC) in combination with miniphlebectomy. The disadvantages and advantages of the modern surgical method of treating venous insufficiency of the lower extremities (EVL) have been identified.

Systematic Review: Safety and Efficacy Comparison of Laser Therapy With And Other Resurfacing Technology

There is an increasing demand of almost all young and adult population for the noninvasive cosmetic procedures specially to enhance the facial appearance and the requirement has expanded all over the world. This review was designed to identify and summarize the literature/evidence from different types of research/clinical studies conducted in facial resurfacing methodologies. A systematic review was designed and conducted in relation to facial resurfacing and rejuvenating techniques using data from PubMed, MEDLINE Cochrane database and Scopus. Systematic review protocol guidelines were used for research questions, aim of the review and PICO breakdown, eligibility criteria and used search engine and extraction of data. A minimum of 17 clinical studies and reviews were identified including randomized clinical trials. Significant results have been obtained in some clinical trials about techniques of rejuvenation and some studies have elucidated contrasting evidence. In most of the work, ablative and non-ablative laser therapy had been compared and we found that some results were compatible, and others showed contrasting evidence. In conclusion, more high-quality randomized control clinical trials are needed to decide on better safety and effectiveness of ablative or non-ablative laser therapy vs conventional treatments.

A rare etiology of frequent ventricular ectopy: Embolic complication of a venous iliac stent to the right ventricle.

Peripheral venous stent migration is an exceedingly rare complication of endovascular stenting. In this clinical vignette, we present a case of a 74-year-old male with a history of endo-venous laser ablation therapy of the right greater saphenous vein complicated with an occlusion requiring a left iliac vein stent. The patient presented to the clinic months after the procedure with complaints of palpitations. Multimodality imaging revealed a stent that had become dislodged and was now located in the right ventricle, trapped within the tricuspid valve apparatus.

Rhinophyma - the end-stage of rosacea

Rhinophyma is defined as a progressive, deforming, nodular enlargement of the sebaceous glands caused by hypertrophy of the sebaceous follicles. It is assumed to be the final phase of chronic rosacea occurring mainly in Caucasian men. This disease negatively affects the quality of life of patients due to decreased self-esteem and depressive disorders. Nasal deformation by narrowing the nostrils impairs the physical performance of patients and even leads to the development of sleep apnea. Treatment is mainly based on surgery to remove pathological tissue. The literature also provides the possibility of therapy using ablative techniques and laser therapy.&#x0D;

Influence of photoactivation on tissue response to different dyes used in photodynamic therapy and laser ablation therapy

Laser ablation therapy (LA) uses Indocyanine Green dye (ICG) which efficiently absorbs laser energy and the increased temperature results in an instantaneous flame that chars tissue and microbes. Photodynamic therapy (PDT) uses different dyes that are activated by light to kill bacteria. This study evaluated the biocompatibility of the dye Curcumin (CUR), Methylene Blue (MB), and Indocyanine Green (ICG) before and after laser activation (ACT). Polyethylene tubes containing one of the dyes were implanted in the subcutaneous tissue of 32 rats (4 tubes per rat) which were divided into 8 groups: C - control (saline solution); C + ACT (Red Laser 660 nm); CUR; CUR + ACT (480 nm blue LED); MB; MB + ACT (Red Laser 660 nm); ICG; ICG + ACT (810 nm Infrared Laser). After 7 and 30 days (n = 8/time), the rats were euthanized and the tubes with the surrounding tissue were removed and processed for histological analysis of inflammation using H&E stain, and collagen fiber maturation using picrosirius red (PSR). A two-way analysis of variance statistical test was applied (p < 0.05). At 7 days, regardless of laser activation, the CUR group showed a greater inflammatory infiltrate compared to the ICG and control groups, and the MB group had a greater inflammation only in relation to the control (p < 0.05). At 30 days, CUR and MB groups showed a greater inflammatory infiltrate than the control (p < 0.05). ICG group was equal to the control in both periods, regardless of the laser activation (p > 0.05). Laser activation induced the proliferation of collagen immature fibers at 7 days, regardless of the dye (p < 0.05). The CUR group showed a lower percentage of immature and mature fibers at 7 days, compared to ICG and control (p < 0.05) and, at 30 days, compared to control (p < 0.05). Regardless of laser activation, the ICG showed the results of collagen maturation closest to the control (p > 0.05). It was concluded that all dyes are biocompatible and that laser activation did not interfere with biocompatibility. In addition, the maturity of collagen was adequate before and after the laser activation. These results demonstrate that the clinical use of dyes is safe even when activated with a laser.

The effect of fractional microablative carbon dioxide laser therapy on vaginal atrophy in menopause women: A review

Vaginal atrophy is one of Genitourinary Syndrome of menopause. This condition occurs due to decreased estrogen levels during menopause. Epidemiological data obtained from several countries estimated that up to 50% of post-menopausal women experience symptoms of vaginal atrophy. This paper aims to conduct a systematic review, and this meta-analysis is to analyze the effect of micro ablative fractional CO2 laser therapy on vaginal atrophy in postmenopausal women. Data was collected online from Pubmed-MEDLINE, Scopus, EBSCO, Cambridge Core, ProQuest, Springer Link, Cochrane Library, and ClinicalTrials.gov databases. Tracking will be carried out in May-July 2023. The population of this study is the result of clinical trial research on the effect of microablative fractional CO2 laser therapy on vaginal atrophy in postmenopausal women. Meta-analysis showed that the VHI score was higher after therapy in the group that received micro ablative fractional CO2 laser compared to the group that received sham laser for vaginal atrophy in menopausal women. VAS scores were lower after administration in the group that received microablative fractional CO2 laser compared to the group that received sham laser for vaginal atrophy in menopausal women. The incidence of side effects in the CO2 laser group did not differ from the sham laser group. This study recommends an RCT study was conducted comparing micro ablative fractional CO2 laser compared to other energy-based devices such as erbium laser and radiofrequency on vaginal atrophy in postmenopausal women so that it can be used as a basis for further systematic review research and meta-analysis.

The State-of-the-Art and Perspectives of Laser Ablation for Tumor Treatment.

Tumors significantly impact individuals' physical well-being and quality of life. With the ongoing advancements in optical technology, information technology, robotic technology, etc., laser technology is being increasingly utilized in the field of tumor treatment, and laser ablation (LA) of tumors remains a prominent area of research interest. This paper presents an overview of the recent progress in tumor LA therapy, with a focus on the mechanisms and biological effects of LA, commonly used ablation lasers, image-guided LA, and robotic-assisted LA. Further insights and future prospects are discussed in relation to these aspects, and the paper proposed potential future directions for the development of tumor LA techniques.

Efficacy of low energy fractional carbon dioxide laser therapy in management of post-surgical hypertrophic scars

Background: aberrant &amp; accelerated wound-healing process that results in hypertrophic scarring causes extracellular matrix &amp; collagen to deposit abnormally in the dermis. After tissue damage occurs, a defensive reaction called tissue repair occurs. Aim; in this review; we aimed to present the effectiveness of low-energy fractional carbon dioxide laser therapy in treating hypertrophic scars following surgery. Summary: A safe &amp; effective approach for treating hypertrophic burn scars is fractional ablative CO2 laser therapy. Even though more treatment sessions have been necessary for satisfying outcomes, a big improvement can be seen after just one round of therapy. Combination therapy with other modalities can decrease the need for repetition of therapy as efficacy increases. Though, in some studies, combination therapy may shorten the duration of studied case downtime &amp; in others, combination therapy may increase side effects. essential for laser energy setting needs to be adjusted for each hypertrophic scar condition. larger research population &amp; longer follow-up period are recommended.

Effects of Ultrasound-Guided Laser Ablation Therapy on Symptomatic Benign Thyroid Nodules, Using EchoLaser – Results of a Pilot Study in the United States

ObjectiveTo evalate the efficacy of single ultrasound-guided laser ablation treatment on symptomatic benign thyroid nodules in outpatient setting, we conducted a single-center, prospective, nonrandomized, open label interventional study. MethodsThis study included adults with normal thyroid function and symptomatic thyroid nodules measuring >29 mm and ≤60 mm with <20% cystic area by ultrasound. Laser ablation energy was calculated based on device guidelines. A single nodule was treated under local anesthesia. Each application session lasted between 400 and 600 seconds under a laser power output of 3 W. ResultsTen subjects underwent the procedure and 9 subjects completed 12-month follow-up. Baseline thyroid nodule volumes ranged from 5.51 to 28.22 mL and the total energy delivered ranged from 1477.00 to 7206.50 J. The average nodule volume reduction at 12 months after procedure for 9 patients was 71.087%. Nodules were visible from >1 m away at baseline for all 10 subjects and not visible in 8 of 10 at 3 months and 6 of 9 subjects at 12 months. Most subjects reported that they would likely undergo the procedure again. No significant adverse events were reported. ConclusionThis study demonstrated the feasibility of performing laser ablation in a clinical setting in the United States. Reduction in nodule volume and symptoms were observed, and the procedure was tolerated well by the subjects.

SMOOTH protocol: A pilot randomised prospective intra-patient single-blinded observational study for examining the mechanistic basis of ablative fractional carbon dioxide laser therapy in treating hypertrophic scarring.

Burn injuries are the fourth most common type of trauma and are associated with substantial morbidity and mortality. The impact of burn injury is clinically significant as burn injuries often give rise to exuberant scarring. Hypertrophic scarring (HTS) is a particular concern as up to 70% of burns patients develop HTS. Laser therapy is used for treating HTS and has shown positive clinical outcomes, although the mechanisms remain unclear limiting approaches to improve its effectiveness. Emerging evidence has shown that fibroblasts and senescent cells are important modifiers of scarring. This study aims to investigate the cellular kinetics in HTS after laser therapy, with a focus on the association of scar reduction with the presence of senescent cells. We will conduct a multicentre, intra-patient, single-blinded, randomised controlled longitudinal pilot study with parallel assignments to achieve this objective. 60 participants will be recruited to receive 3 interventional ablative fractional CO2 laser treatments over a 12-month period. Each participant will have two scars randomly allocated to receive either laser treatment or standard care. Biopsies will be obtained from laser-treated, scarred-no treatment and non-scarred tissues for immune-histological staining to investigate the longitudinal kinetics of p16INK4A+-senescent cells and fibroblast subpopulations (CD90+/Thy1+ and αSMA+). Combined subjective scar assessments including Modified Vancouver Scar Scale, Patient and Observer Scar Assessment Scale and Brisbane Burn Scar Impact Profile; and objective assessment tools including 3D-Vectra-H1 photography, DermaScan® Cortex, Cutometer® and ColoriMeter®DSMIII will be used to evaluate clinical outcomes. These will then be used to investigate the association between senescent cells and scar reduction after laser therapy. This study will also collect blood samples to explore the systemic biomarkers associated with the response to laser therapy. This study will provide an improved understanding of mechanisms potentially mediating scar reduction with laser treatment, which will enable better designs of laser treatment regimens for those living with HTS. ClinicalTrials.gov: NCT04736251.

Efficacy and Safety of Erbium-YAG Laser Ablation Therapy in Superficial Dermatoses

Efficacy and Safety of Erbium-YAG Laser Ablation Therapy in Superficial Dermatoses

Long and Short-terms Effects of Ablative Fractional Laser Therapy on Human Skin: A Network Analysis.

Introduction: Time-dependent effects of laser radiation have been investigated by researchers. An understanding of the molecular mechanism of the time course effect of the laser needs molecular assessment and function evaluation of the related genes. In the present study, the importance of repetition of treatment after 4 weeks and gene expression alteration after 7 days of laser radiation versus one day on the human skin was evaluated via protein-protein interaction (PPI) network analysis and gene ontology enrichment. Methods: The differentially expressed genes (DEGs) were extracted from Gene Expression Omnibus (GEO) and assessed via PPI network analysis. The critical DEGs were enriched via gene ontology. The related biological processes and biochemical pathways were retrieved from "GO-Biological process" and "Kyoto Encyclopedia of Genes and Genomes" (KEGG) respectively. Results: The repetition of laser therapy after 4 weeks of the first treatment did not have a significant effect on treatment efficacy. Sixty-three significant DEGs and six classes of biological terms discriminated the samples seven days after the treatment from individuals one day after the treatment. The studied DEGs were organized into two clusters with certain functions. Conclusion: Based on the findings after laser therapy, several days are required to complete the critical processes such as DNA biosynthesis and skin cornification.