Lasers in Surgery and Medicine最新文献

Background: Postinflammatory hyperpigmentation (PIH) is the most common adverse effect following laser treatments, yet the relative efficacy of proposed prophylactic measures remains uncertain.

Objectives: To compare the effectiveness of available interventions for preventing laser-induced PIH in randomized controlled trials (RCTs).

Methods: PubMed, Embase, Scopus, Cochrane Library, and ClinicalTrials.gov were searched through February 2025. RCTs reporting PIH incidence after laser or other energy-based treatments were eligible. A random-effects network meta-analysis (NMA) combined direct and indirect evidence; treatments were ranked by surface under the cumulative ranking curve (SUCRA).

Results: Fourteen RCTs were included in the systematic review, with 11 included in the NMA. Intradermal tranexamic acid (TXA), topical corticosteroids, topical vasoconstrictors, oral TXA, and epidermal cooling were significantly more effective in reducing PIH incidence compared with sunscreen monotherapy, with intradermal TXA demonstrating the highest efficacy (RR: 0.02, 95% CI: 0.00-0.53). Whitening agents and epidermal growth factor formulations did not show significant benefit over sunscreen, while sunscreen monotherapy was ineffective compared with placebo. Reported adverse events were generally mild, although intradermal TXA was associated with injection site discomfort and bruising.

Conclusion: This systematic review and NMA indicate that topical corticosteroids and intradermal TXA may offer greater protection against laser-induced PIH than sunscreen monotherapy. Preventive strategies should be incorporated into laser treatment planning, particularly for patients with higher risk of hyperpigmentation. Overall, the findings support an evidence-based and individualized approach to PIH prevention. Interpretation should remain cautious due to the limited number and modest sample sizes of included trials.

Introduction: Burn injuries are extremely common, and burn wounds can be associated with prolonged healing due to their inherent biofilm formation on the surface, further increasing the risk of complications such as infection and slow healing. This severely affects the patient's life and represents a socioeconomic burden for the patients and for the healthcare system. Photobiomodulation (PBM) has been introduced in wound management since the 1980s and has shown satisfactory outcomes, with no reported negative outcomes. The effects of PBM on the microbial load of burn wounds were assessed in the burn's outpatient dressing clinic.

Methodology: During routine outpatient dressing changes, wounds were standardly cleansed and a baseline burn wound swab obtained, followed by 2 min of noncontact PBM over the wound bed and peri-wound margin. A repeat wound swab was taken immediately after irradiation, and the wound was redressed with the appropriate dressing for the clinical appearance of the wound. The colony-forming units were counted and compared pre- versus post-treatment bacterial load.

Results: Ninety-six paired swabs from acute burn wounds were analyzed. After a single PBM session, the bacterial load decreased in 42 out of 96 wounds, and increased in nine wounds swabbed out of 96. No bacterial growth was present both before and after PBM in 45 out of 96 wounds. One PBM session on an acute burn wound led to an average of 64.4% decrease in the bacterial load on the burn wound surface. Overall, PBM reduces, or does not increase, the microbial load on 91% of the burn wounds.

Conclusion: PBM is a valuable adjunct in burn wound care by decreasing the microbial load, being noncontact, easy to implement, and conserving the same outpatient clinic settings and length of appointment.

Background and objectives: Skin aging, characterized by wrinkles, pigment disorders, and enlarged pores, is driven primarily by photoaging. While a 1064 nm fractional picosecond laser shows efficacy in skin rejuvenation, comparative studies with intense pulsed light (IPL) remain limited. This randomized controlled trial (RCT) aimed to compare the efficacy and safety of the 1064 nm fractional picosecond laser with IPL in Asian women.

Methods: In this single-center RCT, 38 Asian women (30-60 years) were randomized to receive 1064 nm Nd:YAG picosecond laser with a fractional optic (1064 nm Ps) (n = 19) or IPL (n = 19) therapy for three treatments. Baseline and post treatments Global Score for Photoaging (GSP), fine lines and pigmented spots scores were assessed by two blinded dermatologists based on VISIA photographs. Skin texture, T-zone pores and skin tone were measured with VISIA, C-Cube and Delfin Skin Color Catch. Transepidermal water loss (TEWL) was measured before and after a single treatment by Delfin Vapometer. All adverse events were documented.

Results: 1064 nm Ps outperformed IPL in the periorbital fine lines (p = 0.0315) and T-zone pore counts (p = 0.0473). GSP, infraorbital texture area, pigmented spots and lightness (L*), compared to baseline, significantly improved after treatments in each group, while there was no difference between two groups. Regarding safety, erythema was the most frequent transient response in both groups.

Conclusions: Both 1064 nm fractional picosecond laser and IPL were effective and safe in treatments of facial rejuvenation. Compared to IPL, 1064 nm fractional picosecond laser excelled in periorbital fine lines and T-zone pores.

Clinical trial registration: This trial was registered at ClinicalTrials.gov (identifier: NCT07122310).

Objectives: To assess the efficacy of antimicrobial blue light (aBL) in managing Candida albicans keratitis in rabbit corneas ex vivo and safety to retinal cells in vitro.

Methods: C. albicans (strain CEC-749) suspensions were exposed to aBL with different light irradiance to assess the susceptibility of C. albicans to aBL. An ex vivo C. albicans keratitis model using rabbit corneas infected with a bioluminescent strain CEC-749 was developed. aBL was delivered topically to the infected corneas after fungal inoculation at varying irradiances. Bioluminescent imaging was used to track corneal infection progression in real-time. To evaluate the toxicity of aBL to the retinal cells, photoreceptors (661W) and retinal pigment epithelium cells (ARPE-19) were exposed to aBL in vitro, with cell viability and apoptosis assessed. The viability change of 661W cells under intermittent irradiation of aBL is determined.

Results: At varying irradiances of 25, 50, and 100 mW/cm² and a constant 405 nm blue light exposure of 216 J/cm², 3.39-, 3.67-, and 2.83-log10 CFU of C. albicans were inactivated in suspensions, respectively. Bioluminescence imaging revealed that C. albicans keratitis was fully developed in ex vivo rabbit corneas 24 h following fungal inoculation. After exposure to 288 J/cm² aBL, the fungal burden in the 6, 18, and 24 h-infected rabbit corneas was reduced by approximately 1.57-, 2.18-, and 1.47-log10, as determined by bioluminescence imaging. The viability and apoptosis of both 661W and ARPE-19 cells were significantly affected by continuous aBL delivery at 32.43 J/cm². Intermittent irradiation with a total exposure of 37.50 J/cm², administered as 12.50 J/cm² per irradiation session with 2 h intervals for three sessions, did not affect the viability of 661W cells.

Conclusions: aBL is a potential treatment for C. albicans keratitis. The intermittent irradiation approach using aBL to treat fungal keratitis could be a safety modality for clinical application.

Objectives: To objectively quantify early and mid-term facial tightening after dual-wavelength Er:YAG/Nd:YAG laser treatment in Chinese women using three-dimensional (3D) imaging.

Materials and methods: In this prospective observational study, 13 women with lower facial aging underwent four full-face treatment sessions of dual-wavelength Er:YAG/Nd:YAG (Fotona 4D) at 1-month intervals. Standardized 3D facial images were obtained at baseline and at 1 week, 1, 3, and 6 months after completion of the final treatment session. The primary objective outcomes were vertical displacements (mm) of predefined periocular and midfacial landmarks relative to baseline. Secondary outcomes included Wrinkle Severity Rating Scale (WSRS) scores for nasolabial folds and VISIA pore scores, evaluated at baseline and at 3 and 6 months. Adverse events were recorded.

Results: 3D analysis demonstrated significant early and mid-term tightening in the lateral periorbital region. The vertical distance from the lateral canthus to the nasal base decreased by approximately 0.50-0.63 mm at 1 week and by 0.60-0.63 mm at 3 months bilaterally (all p < 0.05), with partial rebound but persistence of mild improvement at 6 months. The highest point of the zygomatic bone showed a delayed, mild elevation that peaked around 1-3 months. WSRS scores for nasolabial folds decreased by about 1 grade at 3 and 6 months on both sides (all p < 0.001). VISIA pore scores improved from 4.97 ± 0.36 at baseline to 3.37 ± 0.43 at 3 months and 3.73 ± 0.54 at 6 months (both p < 0.001). Only transient erythema and edema were observed.

Conclusions: Dual-wavelength Er:YAG/Nd:YAG laser tightening produced early and mid-term improvements in periocular and midfacial laxity, as captured by 3D landmark displacement, with concomitant improvements in wrinkles and pores. 3D imaging provides a sensitive, objective tool to visualize region-specific dynamic responses to energy-based facial rejuvenation.

Objectives: To summarize the scientific rationale for the use of the monopolar radiofrequency tissue tightening system (monoRF) for the prevention of dermal aging (termed prejuvenation).

Materials and methods: This narrative review summarizes the basic science of dermal aging and monoRF-induced collagen remodeling and neocollagenesis. Studies supporting the mechanism of action of monoRF treatment and its use for prejuvenation are reviewed.

Results: Dermal aging is largely attributed to the accumulation of fragmented collagen and depleted collagen levels. Collagen remodeling and neocollagenesis may be induced by monoRF treatment, resulting in immediate tissue tightening and subsequent collagen production, respectively. Preliminary data and expert opinion suggest that early and repeated intervention with monoRF may prevent progressive skin laxity via synergistic and cumulative effects.

Conclusions: MonoRF treatment shows potential as a prejuvenation strategy, with preliminary evidence supporting that it induces collagen remodeling and neocollagenesis. Future research should focus on long-term, prospective studies to determine the preventive benefits of consistent annual treatment for aging.

Background: Human papillomavirus (HPV) infections are a major cause of oral lesions, and in individuals living with HIV, lesions such as focal epithelial hyperplasia (FEH) may persist or exhibit atypical features, potentially progressing to more severe conditions if untreated. Managing oral HPV lesions in immunocompromised patients is challenging, as conventional therapies may carry higher risks or show limited efficacy.

Methods: This study reports the case of a 49-year-old HIV-positive male with valve disease and arthritis, requiring crutches for mobility. He presented with multiple painless oral lesions, diagnosed as FEH associated with oral HPV, and had previously undergone unsuccessful treatments. Photodynamic therapy (PDT) using methylene blue (MB) and a red laser was proposed as a treatment.

Results: Topical MB-mediated PDT successfully cleared the FEH lesions, with no recurrence observed over 24 months.

Conclusion: PDT mediated by MB is an effective and affordable approach for treating FEH associated with HPV in immunosuppressed patients, offering favorable outcomes and improved quality of life.

Objective: Lichen sclerosus (LS) is a chronic inflammatory dermatosis that predominantly affects the genital region, but can also manifest in other areas of the body. Extragenital LS is often less responsive to standard treatments, necessitating alternative modalities. Herein, we describe the case of a young adult man with a 7-year history of an enlarging sclerotic plaque on the right thigh, refractory to high-potency topical corticosteroids and intralesional triamcinolone.

Methods: The patient underwent three sessions of fractional CO₂ laser combined with platelet-rich plasma (PRP) therapy over 6 months. Pre- and post-treatment biopsies were performed to investigate histologic changes associated with the healing response.

Results: The treatment resulted in near-complete flattening of the plaque and resolution of dermal sclerosis. A post-treatment biopsy confirmed diminished collagen hyalinization, restoration of elastic fibers, and increased fibroblasts and neovascularization. No recurrence was observed at 1-year follow-up.

Conclusion: This case highlights the potential role of fractional CO₂ laser combined with PRP as an effective therapeutic option for recalcitrant extragenital LS. Further studies are warranted to validate this combined approach.

Objectives: To theoretically evaluate the efficacy and safety of large-spot (i.e., > 4 mm) picosecond laser treatment for pigmented lesions in Asian skin using a melanosome disruption threshold fluence (MDTF) model.

Materials and methods: The MDTF model was applied to calculate the required fluence for melanosome disruption with 532, 730, 755, 785, and 1064 nm picosecond lasers. To assess potential complication risks, energy deposition in surrounding tissues was simulated. Additionally, a clinical case series was conducted using a 1064 nm picosecond laser with a large spot size to evaluate its feasibility for treating an ectopic Mongolian spot and a nevus of Ota.

Results: At 532 nm, spot size had minimal impact on the required fluence for epidermal melanosome disruption and on collateral energy deposition. For 730-1064 nm wavelengths, the optimal spot size depended on the lesion depth. When targeting epidermal melanosomes, smaller spot sizes confined energy deposition to superficial layers, reducing collateral exposure. In contrast, for dermal melanosomes, larger spot sizes reduced the required fluence by 39%-65% and lowered collateral energy deposition, while also decreasing variation in required fluence across lesion depths. In the clinical validation, both dermal cases showed good clearance without adverse events, supporting the feasibility of this approach. However, increasing the energy output of laser devices may be necessary to achieve sufficient efficacy.

Conclusion: The theoretical analysis shows that at 532 nm, both small and large spot sizes can be effective for treating epidermal lesions. In contrast, at near-infrared wavelengths, smaller spot sizes are preferable for epidermal lesions, whereas larger spot sizes are advantageous for dermal lesions, potentially lowering the risk of complications while maintaining effective target disruption. These findings provide practical clinical guidance by clarifying wavelength- and spot-size-specific strategies according to target depth. Furthermore, the present results may help optimize treatment parameters and device specifications and inform future clinical studies using large-spot picosecond laser systems.