Lasers in Surgery and Medicine最新文献

Objectives: Spongiotic gingival hyperplasia (SGH) is an uncommon benign, non-plaque-induced epithelial proliferation for which optimal management remains undefined. We describe the case of SGH treated by ablative therapy with a high-power diode laser and summarize previously reported laser-treated cases from the literature.

Methods: An 11-year-old boy presented with a bright-red, granular enlargement of the marginal and attached gingiva adjacent to the mandibular left canine and first premolar. Electronic search was performed in PubMed/MEDLINE, Scopus, Embase, Web of Science, and LILACS to identify studies reporting laser management of SGH.

Results: The lesion was irradiated using an indium-gallium-arsenide diode laser (808 nm, continuous-wave mode, 1.5 W, 748 J, 499 s). Postoperative evaluation revealed excellent hemostasis, preservation of gingival contour, and complete clinical healing without recurrence at 4 months. Five articles comprising eight cases were retrieved. Reported modalities included CO₂ and Nd:YAG lasers and photodynamic therapy with a diode laser. All achieved favorable outcomes, with complete or near-complete remission and no recurrence during 5-24 months of follow-up.

Conclusions: This is the first documented case of SGH managed with high-power diode laser ablation, demonstrating both safety and favorable esthetic outcomes, thereby expanding current therapeutic perspectives for this condition.

Objective: Evaluated the antimicrobial efficacy of curcumin-mediated photodynamic inactivation (PDI) against both sensitive and resistant strains of Streptococcus pneumoniae and Streptococcus pyogenes, as well as its potential to enhance antibiotic effects (amoxicillin, ceftriaxone, erythromycin).

Methodology: The minimum inhibitory concentrations of antibiotics A, B, and C were evaluated in S. pneumoniae and S. pyogenes strains using serial microdilution. Additionally, the photodynamic action of curcumin as a photosensitizer was examined in multiwell plates, which were then irradiated with a 450-nm LED. The effect of the combination over time was determined by colony-forming units per milliliter, using the determined subinhibitory parameters of antibiotics and PDI.

Results: PDI alone significantly reduced bacterial viability, achieving over 3-log reductions at optimal conditions (2.5 µM curcumin, 6.4 J/cm²). When combined with antibiotics, PDI markedly enhanced bactericidal activity, particularly with β-lactams, producing up to 2.8 log greater reductions than antibiotics alone. Notably, three consecutive PDI treatments led to substantial MIC reductions, up to 128-fold for S. pyogenes. We identified that the synergistic effect of curcumin-PDI is highly time-dependent, revealing a dynamic susceptibility window that can be exploited for enhanced antibiotic action. These results support curcumin-PDI as both an antimicrobial tool and a sensitizer agent that enhances antibiotic efficacy.

Conclusion: The study highlights that optimal timing of PDI application is key to maximizing its synergistic effects with antibiotics, revealing that PDI is most effective when applied during specific stages of bacterial response to antibiotic stress, potentially redefining adjuvant treatment strategies.

Background: Existing data on basal cell carcinoma (BCC) clearance rates are predominantly derived from histological sampling or retrospective analyses. Prospective evaluations of clinical clearance remain limited. This study prospectively assessed long-term clinical clearance and scar outcomes following treatment of BCC with a 1064 nm Nd:YAG laser.

Methods: A total of 34 BCC lesions were treated using a 1064 nm Nd:YAG laser and evaluated at approximately 6 and 12 months post-treatment. Each follow-up included assessment for clinical evidence of recurrence and scar evaluation using the Patient and Observer Scar Assessment Scale (POSAS; range 6 = normal skin to 60 = severe scarring) which is a standardized scale.

Results: Twenty-two patients with 34 BCC tumors completed the study. Patients selected laser therapy primarily due to concerns regarding surgical downtime, cosmetic considerations, prior surgical burden, or poor surgical candidacy. Clinical recurrence was identified in one tumor at 6 months, with no additional recurrences observed at 12 months.

Conclusions: At 6 months, 97% of tumors (33/34) demonstrated clinical clearance, and all 33 tumors remained free of recurrence at 12 months. Scar outcomes were favorable, with mean POSAS patient and observer scores of 2.96 and 3.8 (on a 10-point scale), respectively. The 1064 nm Nd:YAG laser represents a promising, cosmetically favorable, and minimally invasive therapeutic option for BCC, particularly in patients who are suboptimal surgical candidates or who prefer non-surgical interventions.

Cover micrograph: The cover image is based on the article Decoding the Mechanisms of Pigment Reduction and Skin Rejuvenation Induced by Picosecond Laser: Insights From a Porcine Model by Hao Wang et al., https://doi.org/10.1002/lsm.70084.

Objective: Given that the therapeutic evidence for doxycycline in rosacea has predominantly been derived from studies on papulopustular rosacea (PPR), this study aimed to evaluate the efficacy and safety of combined oral doxycycline, topical calcineurin inhibitor (TCI), and pulsed dye laser (PDL) therapy in erythematotelangiectatic rosacea (ETR) and to identify clinical predictors of treatment response.

Materials and methods: Medical photographs of patients with ETR treated with oral doxycycline, TCI, and two subsequent PDL sessions were retrospectively reviewed. Erythema on the right cheek was quantitatively measured using computer-aided image analysis.

Results: Of the 79 included patients, 47 had the ETR subtype and 32 had the mixed ETR/PPR subtype. Erythema significantly improved after oral doxycycline and TCI treatment (p < 0.001) and further PDL treatment (p < 0.001). Particularly, in patients with moderate-to-severe ETR, background erythema improved to a level comparable to that observed in patients with mild ETR after treatment (p = 0.307). Post-treatment erythema did not differ by age (p = 0.963) or Fitzpatrick skin type (p = 0.277); however, it was significantly lower among males (p = 0.008) and in patients without prior steroid treatment (p = 0.046). No serious adverse events, including photosensitivity, were observed.

Conclusion: Combined oral doxycycline, TCI, and PDL therapy is effective and safe for ETR, especially in patients with higher severity. Prompt diagnosis and avoidance of steroid misuse may improve treatment responses.

Objectives: To review the efficacy and safety of the dual 1550-nm erbium glass fiber and 1927-nm thulium fiber non-ablative fractional laser system in patients with skin of color (ie, Fitzpatrick skin types [FSTs] III-VI).

Materials and methods: Efficacy, safety, and histologic outcomes were reviewed from 15 clinical studies examining the use of the 1550-nm or 1927-nm wavelength treatment in individuals with skin of color.

Results: Despite variability across study designs, consistent improvement was reported with the 1550-nm wavelength for the treatment of scarring and melasma and the 1927-nm wavelength for the treatment of melasma and photoaging. Postinflammatory hyperpigmentation (PIH) rates varied across studies. Studies directly comparing different settings reported reduced PIH rates with lower energy and/or density. Histologic studies confirmed dermal remodeling and reduced melanin after treatment.

Conclusion: The 1550/1927-nm dual-laser system is safe and effective. Reducing pulse energy and density may confer fewer adverse effects in patients with skin of color. Additional studies are needed, particularly for patients with FST VI and the 1927-nm wavelength treatment.

Objective: To construct a 10.6 μm laser-induced corneal injury model in C57BL/6J mice and observe the wound healing process.

Methods: Four groups of C57BL/6J mice corneas were irradiated with a 10.6 μm laser at dose of 3.0, 4.5, 7.5, and 10.5 J/cm². Corneal injury severity was assessed 1 day after exposure using slit lamp microscopy, optical coherence tomography, and histopathology to determine the optimal dose for constructing corneal injury model. Following this, the corneal wound healing was monitored with the same methods for 6 months.

Results: No corneal damage was observed at dose of 3.0 J/cm². At 4.5 J/cm², a white circular lesion appeared, accompanied by the loss of epithelium and endothelium. At 7.5 and 10.5 J/cm², full-thickness corneal damage was observed, with adhesion to the iris. Therefore, 4.5 J/cm² was selected for constructing the corneal injury model. After injury, the corneas swelled rapidly, reaching maximum at 1 day, and returned to normal by 14 days. From 0hours to 3 days, the corneas exhibited shedding and regeneration of epithelial and endothelial cells, as well as infiltration and regression of inflammatory cells. From 7 days to 6 months, the corneas gradually returned to normal, but some mice still showed stromal hyperplasia.

Conclusion: A moderate corneal injury model can be established in C57BL/6J mice using a 10.6 μm laser at dose of 4.5 J/cm². The acute phase of corneal injury primarily occurs within the first 3 days. While the corneas restore its original physiological structure, transparency may not fully return to normal by 6 months.

Aim: This study aims to perform optical dosimetry in the patient's chest using Monte Carlo simulation, quantifying absorbed optical energy and photon fluence as a function of depth in biological tissue during arthritis rheumatoid photo-treatment.

Method: The MCLTmx code was employed to simulate light transport. A 532, 630, 660, and 850 nm external monoenergetic light source was simulated. The optical energy deposited and photon fluence as a function of depth were calculated under the structural arrangement: source-air-skin-fat-muscle.

Results: Experimental validation was successful. The results indicate that the skin receives, on average, three orders of magnitude more optical energy than fat and muscle for all wavelengths.

Conclusion: The dosimetry developed in this manuscript will serve as a valuable tool to correlate the power of the light source with dosimetric quantities, such as absorbed optical energy and photon fluence, and subsequently with the response to phototreatment. Once this correlation is established, the required irradiation time and power to produce favorable effects in patients suffering from RA can be calculated.

Objectives: Diabetes is one of the most significant chronic metabolic disorders, and diabetic foot ulcers (DFUs) are recognized as one of the most serious complications of this disease due to delayed healing, increased risk of infection, and potential limb amputation. In recent years, noninvasive physical therapies such as low-level laser therapy (LLLT) and polarized light therapy (PLT) or Bioptron have emerged as novel approaches to stimulate wound healing. This study aimed to evaluate and compare the effectiveness of these two therapeutic modalities on the healing process of skin wounds in a diabetic animal model.

Materials and methods: Forty-five male Wistar rats were rendered diabetic using streptozotocin (STZ) and subsequently divided into three groups: control, LLL-treated, and PL-treated. A standardized circular wound was created on the dorsal region of each animal, and treatments were administered daily for seven consecutive days. Wound healing was assessed on Days 0, 3, 5, 7, 14, and 21 using macroscopic analysis and microscopic evaluation on Days 7, 14, and 21 using H&E and Masson's trichrome staining.

Results: LLLT significantly enhanced tissue architecture by stimulating fibroblast activity, promoting angiogenesis, and increasing cellular proliferation. On the other hand, PLT was more effective in reducing wound dimensions and improving the macroscopic healing index. The control group indicated slower and incomplete healing.

Conclusion: Both therapeutic approaches have shown potential to accelerate diabetic wound healing, albeit through distinct mechanisms. The treatment of choice is LLLT for deep wounds and PLT for superficial wounds.