Experimental comparative study of the effect of fractional CO2 laser combined with pulsed dye laser versus each laser alone on the treatment of hypertrophic scar of rabbit ears

Long non-coding RNA CRNDE promotes the progress of hypertrophic scar via regulating the proliferation and migration of hypertrophic scar fibroblasts through targeting microRNA-29a-3p

Hypertrophic scar (HS) represents an excessive fibrotic response during the healing of skin injuries, constituting a common and intricate pathological process that is tightly regulated. This study aimed to explore the clinical significance and potential mechanisms of long non-coding RNA CRNDE in the development of HS. This study encompassed 71 HS patients, and the expression levels of lncRNA CRNDE were assessed via RT-qPCR. Concurrently, the concentrations of collagen I A1 and collagen III A1 were quantified using the Enzyme-linked immunosorbent assay (ELISA) technique, while the cellular activities of hypertrophic scar fibroblasts (HSFs) were evaluated through CCK-8 assays, Transwell migration assays, and flow cytometry. Furthermore, a dual-luciferase reporter gene assay was conducted to confirm the target interaction between CRNDE and microRNA -29a-3p. LncRNA CRNDE was markedly upregulated in HS tissues. Silencing lncRNA CRNDE led to a reduction in collagen I A1 and collagen III A1 levels in HSFs, inhibited cell proliferation and migration, and simultaneously promoted cell apoptosis. Moreover, miR-29a-3p expression was downregulated in HS tissues and exhibited a negative correlation with lncRNA CRNDE expression. The effects of lncRNA CRNDE knockdown on collagen I A1/ III A1 levels, cell proliferation, migration, and apoptosis could be partially mitigated by a miR-29a-3p inhibitor. LncRNA CRNDE influenced the biological behaviors of HS through its interaction with miR-29a-3p.

Combination therapy of pulsed dye laser and ablative fractional carbon dioxide laser for the treatment of pediatric postburn scar: a systematic review

This study aims to determine the effectiveness of combining pulsed dye laser (PDL) and ablative fractional carbon dioxide laser (AFCL) in the treatment of scars in pediatric patients, as well as to identify appropriate treatment parameters, initial treatment timing, and treatment intervals through a systematic literature review. A literature search was conducted between April 6, 2014 and April 6, 2024 in four databases to select studies on the effects of the combination of carbon dioxide fractional laser and pulsed dye laser therapy in children hypertrophic burn scars. This systematic literature review included 497 participants across 8 studies, with individual study sample sizes ranging from 17 to 125 participants. 7 studies reported the gender distribution of participants, with a higher proportion of males (60%, n = 264) than females (40%, n = 170). The average age of the patients was 7.18 years, and scald (62%, n = 235) were identified as the primary cause of scar. The combination therapy of 595 nm PDL and 10,600 nm AFCL significantly improved Vancouver Scar Scale (VSS) / Patient and Observer Scar Assessment Scale (POSAS) score. Study treatment intervals were approximately 1-2 months for simultaneous treatment and 1 month for PDL and 3 months for AFCL for sequential treatment. Two studies investigated the efficacy of early laser therapy (< 3 months), the AFCL laser energy parameters ranged from 30 mJ-50 mJ, significantly lower than the rest of the studies of laser energy parameters, which ranged from 50 mJ-120 mJ. The PDL energy density parameters showed little difference from study to study and were in the range of 5-12 J/cm2. Complications after treatment (4%, n = 22), with rash being the most common (50%, n = 11). Rational use of PDL combined with AFCL (lower laser energy, increase density parameters, shorten treatment intervals (< 1 month)) can safely and effectively treat hypertrophic scars in pediatric burn patients and is superior to single-type laser therapy in efficacy. Significant disorganization was observed among studies suggesting the need to explore high-level evidence-based clinical research that may improve treatment outcomes.

CO2 Laser for Esthetic Healing of Injuries and Surgical Wounds with Small Parenchymal Defects in Oral Soft Tissues

A number of studies have recently demonstrated the effectiveness of CO2 laser irradiation for the repair and regeneration of scar tissue from injuries or surgical wounds. However, such studies of the oral mucosa are highly limited. Previous studies using CO2 laser irradiation have indicated that two factors contribute to esthetic healing, namely, artificial scabs, which are a coagulated and carbonized blood layer formed on the wound surface, and photobiomodulation therapy (PBMT) for suppressing wound scarring and promoting wound healing. This review outlines basic research and clinical studies of esthetic healing with the use of a CO2 laser for both artificial scab formation by high-intensity laser therapy and PBMT in the treatment of injuries and surgical wounds with small parenchymal defects in oral soft tissues. The results showed that the wound surface was covered by an artificial scab, enabling the accumulation of blood and the perfusion necessary for tissue regeneration and repair. Subsequent PBMT also downregulated the expression of transformation growth factor-b1, which is involved in tissue scarring, and decreased the appearance of myofibroblasts. Taken together, artificial scabs and PBMT using CO2 lasers contribute to the suppression of scarring in the tissue repair process, leading to favorable esthetic and functional outcomes of wound healing.

Advances in Photoelectric Therapy for the Early Intervention and Treatment of Traumatic Scars

Traumatic scar is a disease that affected approximately tens of millions of patients worldwide. According to the histological and morphological properties of scars, the traumatic scar typically includes superficial scar, atrophic scar, hypertrophic scar, and keloid. Its formation is a natural consequence of wound healing, regardless of whether the wound was caused by trauma or surgery. However, the production of scars has considerable impacts on the physical and mental health of patients, even causing substantial aesthetic and functional impairments. Prevention or early treatment of scars is the most suitable therapeutic method, including surgical and non-surgical procedures; nevertheless, the benefits of non-operative therapies for scars are quite limited, and surgical treatments are always hard to achieve satisfying outcomes. Through the application of innovative technologies such as lasers, intense pulsed light, and radiofrequency, significant progress has been made in the treatment of traumatic scars. This review highlights the current advancements of photoelectric therapy for the prevention and treatment of various traumatic scars, which may throw light on innovative therapeutic options for scar therapies.