Due to the frequent diagnosis of benign thyroid nodules, it is necessary to deviate from the traditional paradigm based on frequent surgical treatment. This article highlights the evolution of diagnosis and treatment in recent years, beginning from standardization of ultrasound assessment of nodules and cytology results to minimally invasive techniques to reduce the size of symptomatic thyroid nodules. These achievements reduce the number of surgeries, enable more individualized care for patients with benign thyroid disease, reduce long-term complications, and promote cost-effectiveness within healthcare systems. Furthermore, although the use of minimally invasive techniques significantly decreases thyroid nodule volume, the thyroid nodule usually does not disappear and the challenges in this field are discussed (the efficacy of thermal ablation, a variable part of thyroid nodules that remains viable after thermal ablation, some of the nodules treated with thermal ablation may require a second treatment over time and the efficacy of thermal ablation in nodules with different phenotypes). However, although surgery still represents the \"gold standard\" for establishing the final histopathologic diagnosis, it is associated with lifelong thyroid hormone substitution need and serious complications in rare cases. Therefore, it should represent the ultima ratio only after a detailed diagnostic procedure. In the future, artificial intelligence-assisted programs for the evaluation and management of nodules are expected.

OBJECTIVE: To compare foam sclerotherapy through the access sheath (transluminal foam sclerotherapy [TLFS]) combined with endovenous laser ablation (EVLA) with EVLA alone in terms of safety and one-year venous clinical severity score (VCSS) changes in patients with small saphenous vein incompetence.
METHODS: During EVLA, the sheath tip was placed around the targeted tributary vein, and the sclerosant was injected via the side port. Outcomes assessed at 1 day, 1 week, 1 month, and 1 year included VCSS changes, residual or recurrent reflux, the need for secondary interventions, and other related complications.
RESULTS: The change in VCSS did not reach the minimum clinically important difference. Otherwise, TLFS reduced residual or recurrent reflux of the tributary using the TLFS (3/74 legs) compared with the EVLA alone (12/77 legs) (p = .027).
CONCLUSIONS: TLFS is a safe and feasible procedure that reduces residual or recurrent reflux of the tributary vein compared with truncal EVLA alone.

A nanosecond infrared laser (NIRL) was investigated in cutting dental roots. The focus of the investigation was defining the preparation accuracy and registration of thermal effects during laser application. Ten teeth were processed in the root area using a NIRL in several horizontal, parallel incisions to achieve tooth root ablation as in an apicoectomy. Temperature change was monitored during ablation and the quality of the cutting edges in the roots were studied by means of micro-CT, optical coherence tomography, and histology of decalcified and undecalcified specimens. NIRL produced clearly defined cut surfaces in dental hard tissues. The automated guidance of the laser beam created regular, narrow dentin defects that tapered in a V-shape towards the ablation plane. A biologically significant increase in the temperature of the object and its surroundings did not occur during the laser application. Thermal dentin damage was not detected in histological preparations of treated teeth. Defined areas of the tooth root may be ablated using a NIRL. For clinical translation of NIRL in apicoectomy, it would be necessary to increase energy delivered to hard tissue and develop beam application facilitating beam steering for oral treatment.

Flexible, wearable pressure sensors offer numerous benefits, including superior sensing capabilities, a lightweight and compact design, and exceptional conformal properties, making them highly sought after in various applications including medical monitoring, human-computer interactions, and electronic skins. Because of their excellent characteristics, such as simple fabrication, low power consumption, and short response time, capacitive pressure sensors have received widespread attention. As a flexible polymer material, polydimethylsiloxane (PDMS) is widely used in the preparation of dielectric layers for capacitive pressure sensors. The Young\'s modulus of the flexible polymer can be effectively decreased through the synergistic application of sacrificial template and laser ablation techniques, thereby improving the functionality of capacitive pressure sensors. In this study, a novel sensor was introduced. Its dielectric layer was developed through a series of processes, including the use of a sacrificial template method using NaCl microparticles and subsequent CO2 laser ablation. This porous PDMS dielectric layer, featuring an array of holes, was then sandwiched between two flexible electrodes to create a capacitive pressure sensor. The sensor demonstrates a sensitivity of 0.694 kPa-1 within the pressure range of 0-1 kPa and can effectively detect pressures ranging from 3 Pa to 200 kPa. The sensor demonstrates stability for up to 500 cycles, with a rapid response time of 96 ms and a recovery time of 118 ms, coupled with a low hysteresis of 6.8%. Furthermore, our testing indicates that the sensor possesses limitless potential for use in detecting human physiological activities and delivering signals.

The ever-increasing expansion of chemical industries produces a variety of common pollutants, including colors, which become a global and environmental problem. Using a nanocatalyst is one of the effective ways to reduce these organic contaminants. With this in mind, a straightforward and effective method for the production of a novel nanocatalyst based on lignin-derived carbon, titanium dioxide nanoparticles, and Ag particles (TiO2/C/Ag) is described. The preparation of carbon and Ag particles (in sub-micro and nano size) was carried out by laser ablation in air. The nanocomposite was synthesized using a facile magnetic stirrer of TiO2, C, and Ag. According to characterization methods, a carbon nanostructure was successfully synthesized through the laser irradiation of lignin. According to scanning electron microscope images, spherical Ag particles were agglomerated over the nanocomposite. The catalytic activities of the TiO2/C/Ag nanocomposite were tested for the decolorization of methylene blue (MB) and Congo red (CR), employing NaBH4 in a water-based solution at 25 °C. After adding fresh NaBH4 to the mixture of nanocomposite and dyes, both UV absorption peaks of MB and CR completely disappeared after 10 s and 4 min, respectively. The catalytic activity of the TiO2/C/Ag nanocomposite was also examined for the reduction of 4-nitrophenol (4-NP) using a NaBH4 reducing agent, suggesting the complete reduction of 4-NP to 4-aminophenol (4-AP) after 2.30 min. This shows excellent catalytic behavior of the prepared nanocomposite in the reduction of organic pollutants.

BACKGROUND: Redo-transcatheter aortic valve replacement (TAVR) is a promising treatment for transcatheter aortic valve degeneration, becoming increasingly relevant with an aging population. In redo-TAVR, the leaflets of the initial (index) transcatheter aortic valve (TAV) are displaced vertically when the second TAV is implanted, creating a cylindrical cage that can impair coronary cannulation and flow. Preventing coronary obstruction and maintaining coronary access is essential, especially in young and low-risk patients undergoing TAVR. This study aimed to develop a new leaflet modification strategy using laser ablation to prevent coronary obstruction and facilitate coronary access after repeat TAVR.
METHODS: To evaluate the feasibility of the leaflet modification technique using laser ablation, the initial phase of this study involved applying a medical-grade ultraviolet laser for ablation through pericardial tissue. Following this intervention, computational fluid dynamics simulations were utilized to assess the efficacy of the resulting perforations in promoting coronary flow. These simulations played a crucial role in understanding the impact of the modifications on blood flow patterns, ensuring these changes would facilitate the restoration of coronary circulation.
RESULTS: Laser ablation of pericardium leaflets was successful, demonstrating the feasibility of creating openings in the TAV leaflets. Flow simulation results show that ablation of index valve leaflets can effectively mitigate the flow obstruction caused by sinus sequestration in redo-TAVR, with the extent of restoration dependent on the number and location of the ablated openings.
CONCLUSIONS: Laser ablation could be a viable method for leaflet modification in redo-TAVR, serving as a new tool in interventional procedures.

Introduction: The process of laser-induced breakdown of amorphous and crystalline selenium nanoparticles (Se NPs) of various shapes during nanosecond laser fragmentation of aqueous colloidal solutions of nanoparticles with different concentrations has been studied. Methods: The methods of studying the characteristics of plasma and acoustic oscillations induced by optical breakdown are applied. The methods of assessing the concentration of hydrogen peroxide and hydroxyl radicals, the amount of long-lived reactive species of protein and 8-oxoguanine are applied. Results: It has been established that in the process of laser fragmentation of selenium nanoparticles at a wavelength of 532 nm, corresponding to the maximum absorption of selenium, the highest probability of breakdown, the number of plasma flashes, their luminosity and the amplitude of acoustic signals are achieved at concentrations of the order of 109 NPs/mL. It has been shown that the use of selenium nanoparticles of various shapes and structures leads to a change in the photoacoustic signal during laser-induced breakdown. When crystalline selenium nanoparticles are irradiated, the intensity of the photoacoustic response during breakdown turns out to be greater (1.5 times for flash luminosity and 3 times for acoustics) than when amorphous particles are irradiated at the same concentration. It has been shown that selenium nanoparticles exhibit significant antioxidant properties. Selenium nanoparticles effectively prevent the formation of reactive oxygen species (ROS) during water radiolysis, eliminate radiation-induced long-lived reactive species of protein, and reduce the radiation-chemical yield of a key marker of oxidative DNA damage - 8-oxoguanine. Discussion: In general, the intensity of processes occurring during laser fragmentation of amorphous and crystalline selenium nanoparticles differs significantly. The antioxidant properties are more pronounced in amorphous selenium nanoparticles compared to crystalline selenium nanoparticles.

Objective: This study aims to enhance the precision of implant cavity preparation, addressing a notable challenge in the current state of the field by utilizing femtosecond lasers. Background: The application of femtosecond lasers in implant cavity preparation heralds a noninvasive and efficient technique, characterized by diminished thermal damage and high biocompatibility. Despite these promising attributes, the realization of precise cavity preparation remains a significant challenge in the contemporary domain. Materials and Methods: Our research group devised a specialized femtosecond laser microsurgery robotic system tailored for sophisticated implant cavity preparation. This system facilitated the meticulous analysis of sheep shank bone samples, enabling precise three-dimensional cutting. The analysis included an extensive examination of ablation effects, using a laser scanning microscope and VK Analyzer software. This investigation spanned the phases of laser flux calibration and experimental validation, offering a critical evaluation of the automated preparation process. Results: The study delineated that at the focus position of our custom-made oral clinical femtosecond laser microsurgery robotic system, the laser spot diameter is 75.69 μm, and ascertained the ablation threshold for sheep shank cortical bone to be 1.47 J/cm2. Utilizing low laser flux with minimal ablation craters overlap compromised the sidewall precision of the implant cavity, whereas employing high laser flux with extensive ablation craters overlap resulted in an enlarged ablation angle. At a laser energy setting of 2.2362 J/cm2 and a 50% ablation crater overlap, an implant cavity was successfully crafted featuring a top diameter of 4.41 mm, a bottom diameter of 3.98 mm, and a depth of 3 mm, devoid of any adverse thermal effects such as cracking or carbonization. Conclusions: The oral clinical femtosecond laser microsurgery robotic system can achieve automated and precise implant cavity preparation. This advancement promotes the broader application of femtosecond lasers in the field of orthopedics.

OBJECTIVE: To retrospectively analyze the efficacy and safety of laser ablation (LA) and microwave ablation (MWA) in the treatment of papillary thyroid microcarcinoma (PTMC).
METHODS: This was a retrospective study of 103 patients (109 nodules) who underwent thermal ablation for PTMC between October 2019 and March 2023; 61 underwent LA and 48 underwent MWA. The mean patients\' age was 43.50 ± 12.42 years. After ablation, changes in tumor size at different time points, local recurrence, new lesions, lymph node metastasis, and complications were evaluated and recorded. The feasibility, success rate, and safety of LA and MWA were analyzed.
RESULTS: Complete absence of enhancement on contrast-enhanced ultrasonography was observed in all target tumors after ablation. At the last follow-up, the mean volume of the PTMC nodules decreased from 0.09 ± 0.09 to 0.03 ± 0.03 ml (LA group) and from 0.11 ± 0.10 to 0.06 ± 0.08 ml (MWA group) (both, P < 0.05). There was no significant difference in volume change between the groups (P (groups): 0.520; P (groups over time): 0.423), indicating similar efficacy between the groups. There was also no significant difference in the volume reduction rate between the groups during follow-up, except for at 3 months (P = 0.023). The complication rates did not differ between the LA group (8.2 %) and MWA group (6.3 %) (P > 0.05).
CONCLUSIONS: During the short-term follow-up, ultrasound-guided LA and MWA were effective and safe for PTMC, and there were no significant differences in treatment outcomes between the methods.

Laser corneal reshaping is a safe and effective technique utilized to treat common vision disorders. An advanced laser delivery system equipped with a pulsed UV laser with specific parameters is used to ablate parts of the cornea surface to correct the existing refractive error. The argon fluoride (ArF) excimer pulsed gas laser at 193 nm is the most employed type in the commercial devices for such treatments. This laser is generated using a mixture of Argon, Fluorine, and a significant amount of Neon gases. However, due to the ongoing Russian-Ukraine war, the availability of Neon gas is currently very limited, as this region is considered the primary supplier of pure Neon gas. Consequently we suggest replacing the common ArF laser source in the commercial devices with a solid-state (forth harmonic neodymium-doped yttrium aluminum garnet laser at 266 nm). This replacement uses the same operation parameters, optics, and scanning algorithm. Parameters from five commercial devices (Zeiss MEL 90, Technolas TENEO 317, Alcon Wave Light EX 500, Schwind Amaris 750 s, OptoSystems MICROSCAN VISUM) were compared with those of the i-ablation device, a research device that uses a 266 nm laser source. Our goal is to reduce production costs through a simple modification that has a significant impact. Consequently, the present study aims to find an alternative laser source for the current ArF laser without exchanging the complete system\'s design. This recommendation is based on a numerical simulation study. The thermal effect on a human cornea model was numerically evaluated using finite-element solutions of Pennes\' bioheat equation on the COMSOL platform by applying two laser wavelengths. The results demonstrated that changing the laser source significantly impacts the thermal effect, even with the same laser settings. All studied devices showed a reduction in the thermal effect to below 40°C, compared with nearly 100°C under ordinary conditions.