OBJECTIVES:Bioactive surface pre-reacted glass-ionomer (S-PRG) technology and high-power laser irradiation have been investigated as promising preventive approaches. S-PRG particles exhibit multifunctional bioactive glass properties, with the ability to release and recharge ions. High-power laser irradiation of dental enamel induces chemical and structural modifications that enhance enamel resistance. Thus, this study evaluated the effect of Er:YAG laser irradiation, used alone or combined with the bioactive PRG Pro-Care gel, on the reduction of enamel demineralization under cariogenic challenge. METHODS:Human enamel specimens were randomly assigned to five groups (n = 12): control (C), Herjos prophylactic paste (H), laser (L), PRG Pro-Care gel (PRG), and laser + PRG Pro-Care gel (LP). After the treatments, the blocks were subjected to an 8-day pH cycling protocol. The percentage of surface hardness loss (%SHL) was determined through surface microhardness analysis and qualitative analysis was performed by scanning electronic microscopy. RESULTS:Groups L, PRG, and LP showed a significant reduction in mineral loss compared with the control group (p < 0.05), with the LP protocol being superior to PRG alone (p = 0.002). No statistically significant difference was observed between groups L and LP (p = 0.928). Group H did not differ significantly from group C- (p = 0.205). Treated groups presented physical surface alterations after irradiation and bioactive treatment. CONCLUSIONS:Er:YAG laser irradiation, whether used alone or in combination with the PRG gel, promoted a significant protective effect against enamel demineralization, indicating its potential clinical application in the prevention of dental caries.
OBJECTIVES:The 675-nm diode laser has emerged as a novel wavelength for non-ablative skin rejuvenation, with potential advantages in selective dermal targeting and minimal epidermal injury. However, integrated clinical and biologic evidence across multiple esthetic domains remains limited. This study aimed to evaluate the efficacy and safety of high-powered 675-nm laser treatment for facial rejuvenation in a real-world clinical setting. MATERIALS AND METHODS:In this prospective single-center study, 22 adults with facial erythema, fine wrinkles, enlarged pores, and textural irregularities underwent 3 monthly sessions of 675-nm non-ablative diode laser treatment. Objective outcomes were assessed using three-dimensional imaging at baseline and the 3-month follow-up (T3). Blinded Global Esthetic Improvement Scale (GAIS) evaluations were performed for pigmentation and erythema. An exploratory histologic analysis was conducted in a subset of participants. RESULTS:Eighteen participants completed the paired imaging analysis. Significant improvements were observed in wrinkle (+0.73 ± 0.86, p = 0.002), pore (+1.54 ± 2.24, p = 0.010), and smoothness scores (+2.18 ± 2.35, p = 0.001), with large effect sizes (Cohen's dz 0.69-0.93). Blinded GAIS assessments demonstrated ≥ 50% improvement in 61.1% of participants for both pigmentation and erythema. Treatment-related pain was mild (median visual analog scale score: 2.0), and no serious adverse events or post-inflammatory hyperpigmentation were observed. Histologic findings suggested increased dermal collagen components. CONCLUSION:High-powered 675-nm non-ablative diode laser treatment significantly improved objective skin texture parameters and provided clinically perceptible improvements in pigmentation and erythema, with favorable tolerability. These findings support its role as a versatile and effective modality for comprehensive facial rejuvenation.
OBJECTIVES:To evaluate whether erbium-doped yttrium aluminum garnet (Er:YAG) laser conditioning of clinically derived supragingival biofilm-fouled sandblasted, large-grit, acid-etched (SLA) titanium reduces residual biofilm, improves apparent wettability, and supports early osteoblast adhesive retention and osteogenic maturation. METHODS:Supragingival plaque biofilms were generated on SLA titanium discs after 48 h of intraoral splint wear and treated with an Er:YAG laser under saline irrigation. Surface morphology, roughness, wettability, and residual biofilm were assessed by scanning electron microscopy, atomic force microscopy, water contact angle measurement, live/dead fluorescence imaging, and 16S ribosomal RNA gene quantitative polymerase chain reaction. MC3T3-E1 cells were evaluated for spreading, adhesive retention, adhesion- and osteogenesis-related gene expression, alkaline phosphatase activity, and mineralized matrix deposition. RNA sequencing (RNA-seq) was performed at 4 h after cell seeding without detachment challenge and on Day 7 under osteogenic induction. RESULTS:Er:YAG treatment preserved local SLA roughness, reduced residual biofilm burden, and improved apparent wettability. Laser conditioning enhanced early osteoblast spreading and adhesive retention, accompanied by time-dependent changes in Fn1, Col1a1, and Ptk2. 4-h RNA-seq showed limited exploratory transcriptional differences without a coordinated up-regulated focal adhesion or PI3K-Akt signature. On Day 7 under osteogenic induction, laser-treated biofilm-fouled surfaces showed higher Runx2, Alpl, and Spp1 expression and broader enrichment of extracellular matrix-receptor interaction, focal adhesion, regulation of actin cytoskeleton, Rap1/Ras, PI3K-Akt, and mTOR-related pathways. These surfaces also showed higher alkaline phosphatase activity on Day 7 and greater mineralized matrix deposition on Day 14. CONCLUSIONS:Within this supragingival-biofilm model, Er:YAG conditioning preserved local SLA roughness, reduced residual biofilm burden, improved apparent wettability, enhanced early osteoblast adhesive retention, and supported osteogenic maturation. Integrated qRT-PCR and RNA-seq findings indicated stage-specific extracellular matrix-, focal adhesion-, cytoskeleton-, and osteogenesis-related responses, with PI3K-Akt-mTOR representing an exploratory component of the osteogenic-phase network rather than a continuous or causal mechanism.
OBJECTIVES:To systematically evaluate submissions to the CAPER database by analyzing procedural context, characteristics of reported adverse events (AEs), and provider involvement in order to identify patterns with potential implications for patient safety. METHODS:A retrospective review of all reports submitted to the CAPER database from March 2021 to August 2025 was conducted, categorizing cases by procedure type, reported AE, and provider involved. RESULTS:In total, 199 reports describing 298 AEs across 35 various cutaneous procedures were submitted to the CAPER registry from March 2021 to August 2025. Dermatologists performed 62% of reported procedures, while non-dermatologist physicians, non-physicians, and unknown providers accounted for 38%. Filler injections, ablative laser resurfacing, and non-ablative laser treatments were the most frequently reported procedures. Although dermatologists performed most procedures represented in the registry, 51% of reported AEs were associated with procedures performed by non-dermatology providers. Erythema and scarring were among the most frequently reported AEs, while rare but serious events, including vascular compromise and necrosis, were reported following injectable and energy-based procedures performed by a variety of provider types, including non-physicians. CONCLUSIONS:The CAPER registry provides valuable insight into AEs associated with cutaneous procedures and may help identify emerging safety concerns related to new devices or techniques. Broader engagement with AE reporting systems may inform best practices and improve patient safety, particularly as cutaneous procedures increasingly occur outside traditional clinical settings.
BACKGROUND:Prolonged postoperative air leak (PAL) after thoracic surgery remains a major cause of morbidity, extended hospital stays, and bronchopleural fistula. Existing intraoperative aerostasis assessment methods, including water submersion testing, iodine indicator instillation, and ventilator flowmetry, are subjective, anatomically restricted, or provide limited information about the precise location and magnitude of individual leaks. This experimental study evaluates a quantitative intraoperative aerostasis monitoring approach employing a laser photoacoustic leak detector with sulfur hexafluoride SF6 as a biologically inert trace gas marker, configured in a rabbit thoracotomy model. METHODS:Validation proceeded in two sequential phases. Bench-top experiments used a latex-balloon respiratory analogue ventilated under positive end-expiratory pressure conditions (PEEP 490-1500 Pa), with controlled microdefects introduced using a 26 G needle. Acute in vivo studies were conducted in a New Zealand White rabbit (3.2 kg) anesthetized with isoflurane and undergoing left-sided lateral thoracotomy with controlled visceral pleural and bronchial stump defects. SF6 was introduced into the ventilator circuit at 0.02 vol.% (1:5000 v/v). The laser photoacoustic leak detector probe (3 mm inner diameter) was hand-scanned across the operative field while photoacoustic signals were recorded continuously at 10 Hz. A mass-balance model tailored to rabbit ventilatory parameters was derived and experimentally validated to relate measured SF6 concentration to defect efflux rate. RESULTS:All 12 controlled defects (10 visceral pleural and 2 bronchial stump) were detected. During systematic scanning of the exposed lung surface, peak signal-to-background ratios ranged from 155:1 to 540:1 at 3-10 mm probe stand-off distance, with a median localization error of 2 mm (0-4 mm range) relative to the known defect sites. Calculated SF6 efflux rates agreed with theoretical predictions within 14%. Continuous ambient monitoring showed operative-field SF6 concentrations of 0.012-0.058 ppm, more than 13,000-fold below the occupational exposure limit. Introduction of 0.02 vol.% SF6 into the ventilator circuit produced no detectable changes in end-tidal carbon dioxide or ventilatory mechanics compared with baseline. CONCLUSIONS:In this rabbit thoracotomy model, laser photoacoustic SF6 leak detection is feasible, safe, and quantitatively reliable for intraoperative aerostasis assessment. The method offers high sensitivity and millimeter-scale spatial resolution when the operative field is systematically scanned, thereby complementing conventional aerostasis tests that rely on visual detection of air bubbles. These findings should be interpreted as proof-of-concept in an experimental setting. Further work is required to refine the human-machine interface, to assess performance in more complex operative fields and minimally invasive procedures, and to compare this approach with existing acoustic and gas-analysis techniques. The validated mass-balance framework provides a basis for scaling efflux-rate estimation to human ventilatory parameters and for future clinical studies linking intraoperative leak characteristics with PAL.
OBJECTIVE:To elucidate the relationship between immediate whitening (IW), vacuole formation, and melanosome disruption in in vivo human skin following picosecond laser irradiation and to establish a mechanistic basis for clinical endpoint selection in pigmented lesions. METHODS:A 755-nm picosecond laser was applied to in vivo normal human skin under varying irradiation conditions. IW responses were graded clinically. Histological analysis quantified vacuole number density and area, and electron microscopy assessed melanosome morphology. A melanosome disruption threshold fluence model was used to estimate fluence at the dermoepidermal junction (DEJ) and to validate the experimental irradiation conditions. Comparisons with a 755-nm nanosecond laser were performed under endpoint-matched and DEJ fluence-matched conditions. RESULTS:Vacuole area increased with the IW degree. Under slight IW, some vacuoles exceeded the cellular scale (defined by basal cell area), whereas under no IW, vacuoles remained below the cellular scale despite melanosome disruption. These findings indicate that the spatial scale of laser-induced immediate responses shifts from subcellular (no IW) to cellular levels (slight IW). Theoretical analysis confirmed that most irradiation settings exceeded the threshold for melanosome disruption. Compared with nanosecond lasers, picosecond lasers produced more spatially confined vacuole formation at matched IW levels, but larger vacuoles under DEJ fluence-matched conditions. CONCLUSION:IW reflects the spatial scale of picosecond laser-induced immediate responses and serves as a mechanistic indicator for disease-specific clinical endpoint selection. These findings provide a framework for optimizing and standardizing picosecond laser treatment parameters.
OBJECTIVES:Selective photothermolysis with Q-switched ruby laser (QsRL) is used for treatments of dermal melanocytosis. Acute widespread cutaneous manifestations associated with transient systemic effects have rarely been reported. MATERIALS AND METHODS:Patients who developed generalized erythema during QsRL treatment under general anesthesia were retrospectively identified and evaluated. RESULTS:During QsRL treatment, two infants with nevus of Ota and one infant with ectopic Mongolian spots developed generalized erythema. The erythema developed after the initiation of laser treatment rather than after induction of anesthesia. It occurred in non-laser-irradiated areas, including distant regions completely shielded from the laser. The erythema progressed rapidly, resembling an allergic reaction. However, the erythema subsided promptly after QsRL treatment. The borders were distinct without wheals, and reproducibility was observed. In some sessions, transient hypotension followed the erythema. Serum tryptase levels, measured in two infants, were below the cutoff values for anaphylaxis. CONCLUSION:Generalized erythema during QsRL treatment under general anesthesia appears to be transient but may be underrecognized. Laser therapy can induce inflammatory responses, and inflammation-mediated mechanism may contribute to the development of erythema; however, the underlying factors remain unclear.
OBJECTIVES:To systematically evaluate wavefront shaping (WFS) as a strategy for deep-tissue phototherapy, assessing progress and translational readiness across four clinically relevant dimensions. METHODS:Narrative review of three mainstream WFS strategies-feedback iterative optimization, transmission matrix (TM) measurement, and optical phase conjugation (OPC)-evaluated against the core requirements of phototherapy: penetration depth, energy deposition accuracy, dynamic stability, and clinical translation. RESULTS:Time-reversal of ultrasound-encoded (TRUE)-based WFS has achieved TRUE-based WFS has demonstrated focusing through approximately 2 mm of living brain tissue, substantially exceeding the approximately 1 mm limit of conventional optics. Peak-to-background ratios (PBR) exceeding 400 have been demonstrated with natural gradient optimization algorithms, and millisecond-scale system response times have been achieved with digital optical phase conjugation. However, no study has simultaneously demonstrated millisecond-scale correction and sustained, therapeutically effective, and safe light-dose delivery in a living model, and only one study has established a quantitative relationship between WFS optical optimization and a biophysical therapeutic endpoint. CONCLUSIONS:WFS demonstrates compelling optical capabilities that directly address the physical barriers limiting conventional phototherapy. Clinical translation requires a shift from optical demonstration to therapeutic validation, incorporating standardized preclinical protocols, absolute light-dose measurement at the target, and multidimensional biological endpoint assessment.
OBJECTIVES:This manuscript reviews studies on the use of pulsed dye laser (PDL) and intense pulsed light (IPL) for the treatment of cutaneous rosacea, with a focus on their emerging role in managing ocular rosacea. METHODS:A literature search was conducted using the PubMed database with the terms "rosacea and intense pulsed light", "ocular rosacea and intense pulsed light", "rosacea and pulsed dye laser", and "ocular rosacea and pulsed dye laser." Of the 81 initially identified articles, studies not in English and those published before 1999 were excluded to ensure relevance to modern laser technologies. Additionally, review articles and case reports with three or fewer patients were excluded due to limited generalizability and statistical robustness. RESULTS:After applying exclusion criteria, 20 articles remained. Studies consistently demonstrated significant improvement in erythema and telangiectasia following multiple sessions of PDL or IPL, with minimal differences between the two modalities. However, one study reported that IPL treatment was faster to administer. While IPL has been widely studied in ophthalmology for treating dry eye syndrome and meibomian gland dysfunction, it has also been shown to effectively alleviate ocular rosacea symptoms, reducing lid margin telangiectasia and improving meibum expressibility. CONCLUSIONS:PDL and IPL have demonstrated efficacy and safety in managing cutaneous rosacea, and IPL has also proven beneficial for ocular rosacea. These findings support the expanding role of laser and light-based therapies as effective treatment options for patients suffering from rosacea-related symptoms.
ABSTRACT Objectives To evaluate the visual outcomes of Nd:YAG laser posterior capsulotomy performed in the supine position under general anesthesia in children with visual axis opacification after cataract surgery. Materials and Methods A retrospective clinical case series of 13 eyes of 9 children with visual axis opacification following congenital, uveitic, or juvenile cataract surgery was conducted. All patients underwent Nd:YAG laser posterior capsulotomy in the supine position under general anesthesia at the Eye Clinic, University Medical Centre Ljubljana, between September 2019 and November 2025. Results Posterior capsulotomy was successfully performed in all 13 eyes. The median age at treatment was 9.1 years (range: 0.9–14 years) and the median follow‐up was 23.8 months (range: 2–60 months). Mean best corrected visual acuity (BCVA) improved from 0.85 ± 0.60 logMAR preoperatively to 0.64 ± 0.73 logMAR postoperatively ( p = 0.002). Three eyes (23%) required a secondary Nd:YAG capsulotomy due to recurrent VAO. Transient intraocular pressure elevation occurred in two eyes (15%) and resolved with topical treatment. No other complications were observed. Conclusions This study demonstrates the feasibility of performing Nd:YAG laser posterior capsulotomy under general anesthesia to manage VAO in children who are unable to undergo the procedure in the standard seated position.
OBJECTIVES:Paronychia is a common and often painful cutaneous adverse event of epidermal growth factor receptor inhibitor therapy that can impair function and quality of life. We report the first known case of amivantamab-associated paronychia successfully treated with 532-nm potassium-titanyl-phosphate laser. MATERIALS AND METHODS:A 67-year-old man with metastatic non-small cell lung cancer receiving amivantamab developed painful periungual inflammation with pyogenic granuloma-like changes involving multiple fingers and both great toes after failing multiple topical therapies. A representative lesion on the left fourth digit was selected for treatment and underwent two sessions of 532-nm KTP laser therapy. Treated and untreated digits were compared for clinical response. RESULTS:Following two treatment sessions, the treated digit demonstrated marked improvement in erythema, pain, and friability. Untreated digits remained inflamed and symptomatic, serving as a within-patient comparator. No adverse events were observed. CONCLUSION:Given its superficial vascular targeting mechanism and broad clinical availability, the 532-nm KTP laser may represent a practical and effective therapeutic option for refractory EGFRI-associated paronychia. To our knowledge, this is the first reported case of successful treatment of amivantamab-associated paronychia with a 532-nm KTP laser.
OBJECTIVES:Laser lithotripsy carries an inevitable risk of collateral tissue injury. This study compared the safety profiles of pulsed Holmium:YAG and Thulium:YAG lasers by examining their effects on soft tissue under laser settings relevant to lithotripsy, using ex vivo porcine kidney models. METHODS:Direct laser impacts were applied to porcine renal parenchyma and pelvis at constant fiber movements and clinical laser settings (0.2-3.5 J, 10-40 Hz, 2-40 W), with high-power extensions for the Thulium:YAG laser up to 80 W/200 Hz. From 560 histological sections, coagulation and cutting depths were measured and clustered. RESULTS:At equivalent power, the Thulium:YAG laser operated with longer pulses than Holmium:YAG, reducing pulse energy per time (pulse power ≤ 3362 vs. ≤ 7777 W). Holmium:YAG laser produced deeper lacerations up to 9.3 mm in renal parenchyma, compared to 5.0 mm with the Thulium:YAG laser. In renal pelvis, maximal cut depth was 3.6 mm with Holmium:YAG-twice as that observed with the Thulium:YAG. While pulse power was a primary determinant for soft tissue damage, high frequencies (100-200 Hz) did not elevate it. Cluster analysis identified laser-specific damage profiles: Thulium:YAG favored coagulative damage at limited depths, whereas Holmium:YAG induced deep lacerations with limited coagulation and tissue detachment. CONCLUSION:Soft tissue safety and complication risk depend on laser parameters and choice of technology. Reduced pulse powers maximize safety, instead pulse frequency seems safe to elevate for improved efficiency. At power levels beyond 20 W, Thulium:YAG benefited from longer pulses showing safer profiles, with shallower penetration and more reliable coagulation compared to Holmium:YAG.
OBJECTIVES:A novel open-angle glaucoma treatment procedure, femtosecond laser image-guided high-precision trabeculotomy (FLIGHT), non-invasively creates aqueous humor (AH) drainage channels from the anterior chamber (AC) to Schlemm's canal (SC) through the trabecular meshwork (TM). The channels decrease AH outflow resistance, thus decreasing intraocular pressure (IOP). The effect of the procedure greatly depends on the condition of the SC segment where the drainage channel ends. The purpose of this study was to develop a 3D finite element model (FEM) of the FLIGHT procedure in the case of resistive flow of the AH in the SC, including cases of segmental flow resulting from blocked or collapsed segments of the SC. METHODS:We adopted the 3D FEM of the intact glaucomatous eye, including drainage system parameters, from our previous paper to simulate the FLIGHT treatment in eyes with resistive and segmental flow in the SC. The TM, SC and collector channels (CCs) were modeled as porous materials, with assigned permeability, to approximate the outflow resistance found in these tissues in-vivo. The permeability of segments of the SC was varied to model resistive and segmental flow within the SC. The FLIGHT treatment was simulated by removing block-like pieces of the TM to create channels that connected the AC to the SC. The size and locations of collapsed segments of SC in the FEM were varied to investigate their impact on IOP reduction following simulated FLIGHT. RESULTS:The FEM simulation results showed that the IOP reduction was maximized when FLIGHT drainage channels were in "free flow" segments of SC. Conversely, channels connecting the AC to blocked or collapsed regions of SC had a significantly diminished effect on IOP reduction. However, this was mitigated by replacing a single drainage channel with multiple channels that bypass the TM in different locations, including "free flow" segments. CONCLUSIONS:The condition of SC distal to the FLIGHT drainage channels has a significant influence on IOP reduction. The importance of multiple drainage channels targeting more segments of the SC is highlighted to mitigate the effect of collapsed segments of the SC.
BACKGROUND:Staphylococcus aureus (S. aureus) is a major cause of skin, wound, and device-related infections. Blue light (405-470 nm), shows promise for treating this organism. However, the translatability, dosing parameters, safety, and effectiveness remain unclear, and no systematic review currently exists. OBJECTIVES:To evaluate the antimicrobial efficacy and safety of blue light therapy against S. aureus across experimental models. METHODS:All relevant in vitro, in vivo, and clinical studies were identified through systematic searches of PubMed, Embase, Web of Science, Cochrane Library, Scopus, and ClinicalTrials. gov. Studies evaluating blue light without exogenous photosensitizers reporting bacterial or clinical outcomes were included. Risk of bias was assessed using SYRCLE. This study was registered with PROSPERO (ID: CRD420251089518). RESULTS:A total of 33 articles met inclusion criteria: 20 planktonic models, 6 biofilm models, and 17 methicillin-resistant S. aureus (MRSA) specific outcomes. The predominant wavelength tested was 405 nm (87.9%). Blue light reduced bacterial burden across models, though results varied by dose and experimental conditions. Additionally, 57.6% of studies did not report statistical significance. CONCLUSIONS:Blue light demonstrates antimicrobial activity against S. aureus, including MRSA, but heterogeneity in study design and limited in vivo data restrict clinical translation. We propose a standardized set of 8 reported parameters for future blue light studies.
OBJECTIVES:To report the first case of Koebner phenomenon induced by picosecond laser treatment in a patient with psoriasis. We analyzed the clinical and histopathological features and discussed the possible mechanism by which the laser's photomechanical effect triggered the reaction. METHODS:A 58-year-old woman with well-controlled plaque psoriasis underwent 755-nm picosecond alexandrite laser treatment (pulse duration: 750 ps; fluence: 3.77 J/cm2; spot size: 3 mm) for seborrheic keratoses on the back and lower waist. Clinical, dermoscopic, and histopathological assessments were performed. RESULTS:One month after treatment, erythematous, scaly plaques emerged at the laser-irradiated sites. Clinical and dermoscopic findings were consistent with psoriasis. Histology confirmed psoriasiform changes, and immunohistochemistry demonstrated a T-cell-predominant infiltrate (CD3+) with dermal CD4+ predominance and epidermal CD8+ enrichment. Notably, no Koebner phenomenon was seen in coexisting melanocytic nevi. Lesions resolved after 4 weeks of topical corticosteroids, with no recurrence up to 4 months. CONCLUSIONS:To our knowledge, this is the first report of the Koebner phenomenon induced by picosecond laser therapy in a patient with psoriasis. Although picosecond lasers are known for minimal thermal damage, their photomechanical effects may activate immune responses and trigger new psoriatic lesions. Therefore, caution and careful monitoring are advised when using picosecond lasers in patients with psoriasis.
