Lasers in Medical Science最新文献

Cardiovascular disease (CVD) is a major cause of unnatural death worldwide, so timely diagnosis of CVD is crucial for improving patient outcomes. Although the traditional diagnostic tools can locate plaque and observe inner wall of blood vessel structure, they commonly have radioactivity and cannot detect the chemical composition of the plaque accurately. Recently emerging Raman techniques can detect the plaque composition precisely, and have the advantages of being fast, high-resolution and marker-free. This makes Raman have great potential for detecting blood samples, understanding disease conditions, and real-time monitoring. This review summarizes the origin and state-of-art of Raman techniques, including the following aspects: (a) the principle and technical classification of Raman techniques; (b) the applicability of Raman techniques and its comparison with traditional diagnostic tools at different diagnosis targets; (c) the applicability of Raman spectroscopy in advanced CVD. Lastly, we highlight the possible future applications of Raman techniques in CVD diagnosis.

The use of polylactic acid (PLA) coated with photosensitizer (PS) and activated by visible light could represent a novel, inexpensive, and eco-friendly self-sterilizing material to produce customized biomedical devices with antimicrobial properties. The rise of antibiotic resistance highlights the urgent need for alternative antimicrobial strategies, like Methicillin-resistant Staphylococcus aureus (MRSA), which represents a major global health concern, responsible for severe invasive diseases to minor skin infections and asymptomatic nasal colonization. Antimicrobial photodynamic inactivation (aPDI) has emerged as a promising technique, using the synergistic effects of light, oxygen, and a photosensitizer to generate reactive oxygen species (ROS) that eradicate bacteria. Brazil's rich biodiversity offers a reservoir of natural compounds, such as Eugenia uniflora (EU) extract, which has demonstrated effective antimicrobial activity when used in aPDI. This study explored the development of a 3D-printed self-sterilizing surface by combining aPDI and EU extract to combat MRSA. Polylactic acid (PLA) discs were impregnated with EU extract and evaluated for their ability to reduce MRSA colonies under visible light, assessing bacterial growth at 0, 8, and 24 h. Results showed significant reductions in MRSA colonies under visible light after 8 h (~ 50%), which were enhanced at 24 h (~ 70%). ROS involvement was confirmed, with EDTA and azide restoring ~ 50% of bacterial growth, implicating metal ions and singlet oxygen in the mechanism. DNA damage assays revealed heightened genotoxic effects under light exposure, as shown by DNA smearing. This innovative approach underscores the potential of EU coated 3D-printed surfaces in reducing nosocomial infections. Further studies will examine ROS generation and antibiofilm capabilities.

Prostate cancer diagnosis relies on methods like PSA testing, digital rectal exams, and biopsies. The Z-scan technique, a nonlinear optical method, may provide a new, non-invasive approach to detecting circulating free DNA (ccfDNA) in serum, offering potential improvements in cancer diagnosis and monitoring. The aim of this study is to evaluate whether the Z-scan technique can serve as an alternative or complementary diagnostic tool to existing prostate cancer tests. The Z-scan technique was applied to detect apoptotic and necrotic ccfDNA fragments in the serum or plasma of prostate cancer patients. This technique measures the nonlinear refractive index's dispersive and absorptive components and was compared with laboratory data, such as PSA levels and cancer progression indicators. The study found a correlation between Z-scan-derived θ values and PSA levels, suggesting its utility in identifying cancer relapse. However, no correlation was observed with the Gleason scale. The Z-scan technique shows promise as a diagnostic and monitoring tool for prostate cancer, offering a potential non-invasive alternative to traditional methods.

Six Sigma and DMAIC methodology are potent quality improvement tools that can significantly improve healthcare processes. This article provides an overview of the DMAIC framework and demonstrates its application in improving procedures for physicians performing laser resurfacing and tattoo removal procedures. This methodology begins with defining clear objectives and assembling a dedicated team, followed by measuring and analyzing Critical-to-Quality variables using statistical tools. Improvement strategies are then developed and tested, with control measures implemented to ensure successful outcomes are maintained over time. By systematically following the DMAIC phases, teams can identify areas for improvement, proactively implement changes, and ultimately minimize adverse outcomes associated with medical laser procedures. Adapting the DMAIC framework for dermatological laser procedures offers a structured approach to enhance treatment effectiveness, patient satisfaction, and standardize care, ultimately reducing the risks and side effects associated with these procedures.

Prior laser studies have demonstrated that as the temperature of a medium increases, the amount of energy delivered to the target increases. We sought to investigate the role of irrigation fluid temperature on Thulium fiber laser (TFL) urolith ablation. 360 calculi were divided in vitro according to chemical composition: calcium oxalate monohydrate (COM), cystine (CYS), struvite (STR), calcium phosphate (CAP), uric acid (UA), and calcium oxalate dihydrate (COD). A 200 μm TFL was placed directly on each stone, while immersed in 0.9% NaCl at four different temperatures (25 C, 37 C, 44 C, 60 C) and a single laser pulse administered at distinct energy settings (0.1 J, 0.5 J, 1.5 J). Optical coherence tomography assessed the resulting ablation cone volume. Mean stone volume and porosity were evaluated through ANOVA and Tukey post-hoc analysis. A multivariate generalized model for each composition accounted for the impact of fluid temperature and laser energy on stone ablation. Warmer fluid temperatures yielded greater ablation cone volumes for most energy settings, excluding UA stones. When accounting for chemical composition, higher tensile strength stones (COM, CYS) benefited most from warmer fluid in comparison to frangible stones (CAP, STR). The effects of increasing fluid temperature are modest relative to laser pulse energy as a large temperature increase (i.e. 7ºC) is equivalent to a minor energy increase (i.e. 0.1 J). For non-UA stones, TFL ablation efficiency increases with warmer irrigation fluid. The effect, albeit modest compared to laser pulse energy, was most notable for COM and CYS stones.

With recent developments in laser technologies and growing demand for alternative treatments, laser therapy has been increasingly studied as a treatment for androgenetic alopecia (AGA). Low-level laser therapy (LLLT) and fractional laser therapies have been marketed as safe and effective options for treating AGA in comparison with traditional drug therapies, which are associated with unwanted side effects. We discuss the history of development and implementation of laser devices for treatment of hair loss and outline the proposed mechanism of action for LLLT and fractional lasers. Additionally, we summarize the evidence of efficacy for LLLT and fractional laser monotherapies in the treatment of AGA and assess potential risk of bias in available clinical studies. While evidence is still mounting, there exists some congruency in proposed mechanisms for the stimulation of hair follicles by laser therapy. Laser light is believed to foster a supportive microenvironment for the hair follicle, through improved vascularization and modulation of inflammation, and directly stimulate growth signaling in the follicle. As for evidence of clinical efficacy, studies of LLLT and fractional laser monotherapies have reported improvement in AGA markers from baseline values. However, these studies have a relatively small sample size and our risk of bias assessment suggests some concerns in procedural design. Although laser therapy represents a safe alternative treatment option for AGA, its evidence of efficacy is hindered by a lack of large-scale, high-quality clinical trials, susceptibility to bias, and a wide range of devices, treatment protocols and parameters.

This study aimed to systematically verify the available systematic reviews and meta-analyses of Low-level laser therapy (LLLT) in diabetic foot ulcer (DFUs) to identify the effects and optimal parameters of LLLT in the management of DFUs. This umbrella review was written according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) report items and registered in the International Prospective Register of Systematic Review (PROSPERO). The search for articles was performed in the Pubmed, Scopus, Web of Science and Embase databases. The following terms were used: Diabetic Foot, Diabetic Neuropathies, Peripheral Vascular Diseases, Peripheral Neuropathy, Diabetic Foot Ulcer, LASER Therapy, Low-Level Light Therapy, LLLT, LASER Biostimulation, Low Intensity LASER Irradiation, Low Power LASER Irradiation, Low Intensity LASER Therapy, Low Power LASER Therapy. A search was performed in the references section of the included studies. The systematic review (SR) included studies that compared LLLT with non-therapeutic doses (parameters considered low to modify healing), sham irradiation, and conventional DFU treatment. The interventions were performed using red and infrared wavelengths. Although two studies included in the SR used wavelengths below 600 nm, these were combined with diodes with infrared wavelengths within the same device. Another study performed a comparative analysis of LLLT at different wavelengths (632 nm and 904 nm), with area reduction rates of 63.7% and 56.8%, respectively, with no statistically significant difference. This is study indicated that, compared with standard treatment and non-irradiation treatments, the use of photobiomodulation (PBM) with different parameters was effective in promoting UPD healing. Further studies are warranted to determine the ideal parameters for improving patient outcomes. (International Prospective Register of Systematic Review Registration number: CRD42022362447).

This study aimed to systematically review the literature for laboratory studies that evaluated the influence of mono- and polywave light-emitting diode (LED) devices on the degree of conversion (DC) of composite resins and adhesive systems. A search of three electronic databases (PubMed, Web of Science, Scopus) and using Google Scholar was conducted through June 2024 to identify eligible studies that compared monowave and polywave LED devices on the DC of composite resins and adhesive systems. Studies that evaluated DC using indirect methods, material other than composite resin and adhesive system, and missing DC values as mean and standard deviation were excluded. Meta-analysis was performed at a significance level of ≤ 0.05 comparing DC values (mean and standard deviation) produced by LEDs. Heterogeneity was quantified using I² values. 79 potentially relevant studies were identified from online databases, 27 were selected for full-text assessment, and 22 were included in this systematic review. Eighteen of the included studies had a high risk of bias and four had a moderate risk of bias. Polywave LEDs significantly improved the DC of composite resins (p ≤ 0.5) and did not affect on adhesive systems (p = 0.18). Despite the high risk of bias and the heterogeneity of the included studies, the available evidence may support the conclusion that polywave LED devices improve the DC of composite resins. Monowave or polywave LED devices did not affect the DC of adhesive systems.

This bibliometric analysis aimed to analyze global research trends in laser therapy for hemangiomas, a common benign vascular tumor in children from 1977 to 2024. Publications in laser therapy for hemangiomas from 1977 to 2024 were retrieved from the Web of Science Core Collection (WoSCC) database, and only articles published in English were analyzed. Bibliometric and visual analyses were performed using VOSviewer, CiteSpace, and the R package "bibliometrix." A total of 1,028 publications from 66 countries and 4,199 authors were analyzed, showing an annual growth rate of 5.61%. The United States led with 365 articles and 11,713 citations. Major contributors included the University of California System and Harvard Medical School, and key journals were Lasers in Surgery and Medicine and Dermatologic Surgery. Pulsed dye laser (PDL) was the most studied laser type. Research focused on optimizing treatment safety, effectiveness, and management, especially in children. The rise of propranolol as a keyword highlighted its increasing role in hemangioma therapy, and the keyword like "classification" and "vascular anomalies" underlining the importance of accurate diagnosis and classification. This study highlights the growing importance of laser therapies for hemangiomas. Future research should explore combining propranolol with laser treatments and the role of precise diagnosis in improving treatment outcomes.