Search Results (13)

Background and Objectives: Because of its consistently high stone-free rates (SFRs), percutaneous nephrolithotomy (PCNL) continues to be the first-line treatment for renal stones larger than 20 mm. Standard 24 to 30 Fr access tracts, however, are linked to access-related morbidity, such as bleeding, pain, and extended hospital stays. These restrictions have led to progressive tract miniaturization and the development of mini-PCNL, ultra-mini PCNL, and micro-PCN techniques. Materials and Methods: We performed a narrative review of studies published through January 2026 using PubMed and Google Scholar. Search terms included percutaneous nephrolithotomy, mini-PCNL, ultra-mini PCNL, micro-PCNL, and vacuum-assisted PCNL. Original studies, systematic reviews, and meta-analyses reporting clinical outcomes, complications, and advancements were selected, whereas conference abstracts, non-English papers, and articles without accessible full text were excluded. Results: Across randomized trials, miniaturized PCNL generally preserves efficacy when patients are selected appropriately. Across randomized trials and meta-analyses, miniaturized PCNL achieved stone-free rates comparable to standard PCNL (typically ~80–90% for stones ≤20 mm and similar rates in selected stones >2 cm), while demonstrating lower hemoglobin decrease (mean difference approximately −0.6 to −1.0 g/dL), reduced transfusion rates, and shorter hospital stays, at the cost of longer operative time (mean difference ~8–12 min). On the other hand, operative time may increase, and smaller working channels can make visualization and fragment evacuation more demanding as stone burden rises. Raised intrarenal pressure is a recurring safety issue because it may increase infectious risk unless drainage is actively managed. Recent innovations aim to address these limitations, including vacuum-assisted access sheaths, pressure-controlled irrigation, improved laser and lithotripsy platforms, image-fusion guidance, navigation systems, and robotic assistance. Conclusions: PCNL now spans a spectrum of tract sizes rather than a single standard approach. When chosen appropriately and performed with attention to pressure control and fragment evacuation, miniaturized PCNL can reduce morbidity without sacrificing stone clearance. Future advancements in percutaneous stone surgery are more likely to rely on integrated technological solutions that improve accuracy, safety, and repeatability than on additional tract size reduction. Full article

Background/Objectives: This study evaluates whether ultrawide-field optical coherence tomography angiography (UWF-OCTA) can guide navigated laser therapy for non-perfused areas (NPAs) in branch retinal vein occlusion (BRVO). It further explores whether the laser spots can be accurately placed according to plan, considering that the retina is three-dimensional (3D), while UWF-OCTA provides two-dimensional (2D) images. Methods: UWF-OCTA images from three devices—VG200, Xephilio OCT-S1, and Bmizar—guided the treatments. These images were superimposed onto NAVILAS^® system images to guide NPA treatments. Pre-treatment planning was strategically designed to avoid normal and collateral vessels, with immediate post-laser OCTA and en face images assessing the efficacy of the laser spots in avoiding these vessels as planned. The accuracy of navigated laser therapy was further analyzed by comparing the intended laser locations with the actual spots. Results: All montaged OCTA images from the three devices were seamlessly integrated into the navigated laser system without registration errors. All patients received treatments targeting the NPAs as planned. However, not all collateral or normal vessels were successfully avoided by the laser spots. A further analysis revealed that the actual locations of the laser spots deviated slightly from the planned locations, particularly in the mid-periphery areas. Conclusions: UWF-OCTA-guided navigated laser photocoagulation is feasible and precise for treating NPAs in BRVO. Nonetheless, minor deviations between planned and actual locations were observed. This discrepancy, particularly important when treating diseases of the macular area, should be carefully considered when employing OCTA-guided navigated laser photocoagulation. Full article

The early history of retinal laser therapy began with the observation of solar blindness, leading to the development of various laser technologies for treating retinal diseases. The first retinal photocoagulation machine was developed in 1956, and subsequent advancements introduced ruby and argon lasers. While conventional theories posited that retinal damage was an indispensable prerequisite for therapeutic effects, emergent insights highlight the non-damaging mechanisms, such as photostimulation- and self-repair-related mechanisms. Novel therapies, such as subthreshold micropulse laser (SMPL) and selective retina therapy (SRT), are now being employed alongside innovative delivery systems to improve treatment efficiency and safety. Clinical studies are underway to evaluate the efficacy of these therapies for conditions like diabetic retinopathy and central serous chorioretinopathy. Despite the challenges in standardization and long-term evaluation, these innovations represent significant progress towards safer and more effective laser treatment for retinal diseases. Full article

Background: Diabetic retinopathy (DR), as a complication of diabetes mellitus (DM), remains a significant contributor to preventable vision impairment in the working-age population. Laser photocoagulation is essential in treating DR in conjunction with anti-vascular endothelial growth factor (VEGF) injection, steroids, and vitrectomy. This review summarizes the history of laser photocoagulation and highlights its current role and long-term effectiveness in real-world conditions. Methods: The National Clinical Trial (NCT), PubMed, Google Scholar, and China National Knowledge Infrastructure (CNKI) databases were searched utilizing combined or individual keywords, and a total of 121 articles were reviewed by the authors. Results: Several novel laser photocoagulation technologies, such as patterned scanning laser, subthreshold micropulse laser, navigated laser, multimodal imaging-guided laser, and retina rejuvenation therapy, substantially decrease the adverse effects and improve the accuracy and security of laser therapy. Numerous studies have demonstrated the outstanding clinical efficacy of combination therapies with pharmacologic treatments like anti-VEGF in treating DR and diabetic macular edema (DME). A 20-year follow-up retrospective study in our center preliminarily demonstrated the long-term effectiveness of conventional laser photocoagulation. Conclusions: More clinical trials are required to confirm the clinical effectiveness of novel laser technologies. Better treatment protocols for the combination therapy may be detailed. Anti-VEGF treatment has better effects, especially for DME and in a short period. But in real-world conditions, given the long-term effectiveness and economic advantages of conventional laser treatment, it should be prioritized over anti-VEGF injection in certain situations. Full article

This study presents the development of a route planner, called Mission Planner, for an agricultural weeding robot that generates efficient and safe routes both in the field and on the farm using a graph-based approach. This planner optimizes the robot’s motion throughout the farm and performs weed management tasks tailored for high-power laser devices in narrow-row crops (wheat, barley, etc.) and wide-row crops (sugar beet, maize, etc.). Three main algorithms were integrated: Dijkstra’s algorithm to find the most optimal route on the farm, the VRMP (Visibility Road-Map Planner) method to select the route within cultivated fields when roads are not visible, and an improved version of the Hamiltonian path to find the best route between the crop lines. The results support the effectiveness of the strategies implemented, demonstrating that a robot can safely and efficiently navigate through the entire farm and perform an agricultural treatment, in this case study, in laser-based weed management. In addition, it was found that the route planner reduced the robot’s operation time, thus improving the overall efficiency of precision agriculture. Full article

Background and Objectives: This study aimed to elucidate the role of laser photocoagulation therapy in the treatment of diabetic macular edema (DME) as an alternative to, or in conjunction with, the first-line treatment, anti-vascular endothelial growth factor (VEGF). Materials and Methods: A comprehensive literature search to identify studies that evaluated the efficacy of laser photocoagulation therapy in the management of DME was performed. The relevant findings of the efficacy of focal/grid laser therapy from data in randomized, controlled trials were synthesized, and the potential of new laser technologies, such as navigated laser systems, pattern scan lasers, and subthreshold lasers, was explored. The usefulness of multimodal imaging-guided laser therapy was also evaluated, with a focus on the potential contribution to anti-VEGF therapy. Results: Focal laser photocoagulation targeting microaneurysms remains an effective therapeutic approach to chronic refractory edema, despite the widespread use of anti-VEGF therapy. To achieve the best possible treatment outcomes, precise identification of microaneurysms is essential. This requires the use of multimodal imaging-guided, highly accurate, minimally invasive coagulation techniques. Subthreshold laser therapy can also reduce the frequency of anti-VEGF injections and minimize treatment burden. Conclusions: Further studies are needed to determine the optimal timing and settings for laser photocoagulation therapy and the potential of new laser technologies in the management of DME. Nevertheless, laser photocoagulation therapy plays an important role in the management of DME, in conjunction with anti-VEGF therapy. Full article

The utilisation of miniature robots has become essential in the domain of minimally invasive surgery and long-distance delivery of nanomedicine. Among these, the miniature magnetic continuum robot (MCR) stands out because of its simple structure and dexterity, which allow it to penetrate small cavities, transport specialised tools such as a laser, and deliver medications to support surgical treatment. Nevertheless, because of their soft bodies with a single stiffness, conventional MCRs have limited controllability when navigating through intricate cavities. To address this limitation, we propose a novel concentric magnetic continuum robot (C-MCR) comprising a concentric magnetic catheter with a guidewire having varying stiffness. The C-MCR allows substantial curvature bending owing to its difference in stiffness, and its detachable nature allows it to have four working modes to adapt to specific application requirements with improved stiffness controllability. Experiments demonstrate the ability of the C-MCR to navigate complex pathways and deliver nanomedicines over long distances to specific areas via its internal channels using a large homemade eight-coil electromagnetic system. The C-MCR offers promising application prospects for the long-distance delivery of tailored nanomedicines because of its simple operation, reduced risks, and larger attainable workspace. Full article

The prevalent cause of retinal detachment is a full-thickness retinal break and the ingress of fluid into the subretinal space. To prevent progression of the detachment, laser photocoagulation (LPC) lesions are placed around the break in clinical practice to seal the tissue. Unlike the usual application under indirect ophthalmoscopy, we developed a semi-automatic treatment planning software based on a sequence of optical coherence tomography (OCT) scans to perform navigated LPC treatment. The depth information allows demarcation of the border where the neurosensory retina is still attached to the retinal pigment epithelium (RPE), which is critical for prevention of detachment progression. To evaluate the method, artificially provoked retinal breaks were treated in seven ex-vivo porcine eyes. Treatment outcome was assessed by fundus photography and OCT imaging. The automatically applied lesions surrounding each detachment (4.4–39.6 mm²) could be identified as highly scattering coagulation regions in color fundus photography and OCT. Between the planned and applied pattern, a mean offset of 68 µm (SD ± 16.5 µm) and a mean lesion spacing error of 5 µm (SD ± 10 µm) was achieved. The results demonstrate the potential of navigated OCT-guided laser retinopexy to improve overall treatment accuracy, efficiency, and safety. Full article

Hepatocellular carcinoma (HCC) is a tumor that poses a serious threat to human health, with an extremely low five-year survival rate due to its difficulty in early diagnosis and insensitivity to radiotherapy and chemotherapy. To improve the therapeutic efficiency of HCC, we developed a novel multifunctional nanoplatform (SCF NPs) with an amphiphilic polymer (Ce6-PEG2000-FA) and a multitarget tyrosine kinase inhibitor sunitinib. SCF NPs showed superior therapeutical efficiency for HCC due to the synergetic effect of molecular targeted therapy and phototherapy. The Ce6-PEG2000-FA not only serves as a nanocarrier with excellent biocompatibility but also can act as a therapeutic reagent for photothermal therapy (PTT) and photodynamic therapy (PDT). Furthermore, the folic acid group of Ce6-PEG2000-FA enhanced the active targeting performance of SCF NPs. As a multitargeted tyrosine kinase inhibitor, sunitinib in SCF NPs can play a role in molecular targeted therapies, including tumor growth inhibition and anti-angiogenesis. In vivo experiments, SCF NPs showed multimode imaging capabilities, which can be used for tumorous diagnosis and intraoperative navigation. Meanwhile, SCF NPs showed outstanding synergetic tumor inhibition ability. Tumors of SCF NPs group with laser radiation were eradicated without any recrudescence after 14 days of treatment. Such theranostic nanoparticles offer a novel therapeutic tactic for HCC. Full article

Selective therapy and controlled drug release at an intracellular level remain key challenges for effective cancer treatment. Here, we employed folic acid (FA) as a self-navigating molecule in nanoconjugates containing quantum dots (QDs) and β-cyclodextrin (β-CD) for the delivery of antitumor unsymmetrical bisacridine compound (C-2028) to lung and prostate cancers as well as normal cells. The bisacridine derivative can form the inclusion complex with β-cyclodextrin molecule, due to the presence of a planar fragment in its structure. The stability of such a complex is pH-dependent. The drug release profile at different pH values and the mechanism of C-2028 release from QDs-β-CD-FA nanoconjugates were investigated. Next, the intracellular fate of compounds and their influence on lysosomal content in the cells were also studied. Confocal Laser Scanning Microscopy studies proved that all investigated compounds were delivered to acidic organelles, the pH of which promoted an increased release of C-2028 from its nanoconjugates. Since the pH in normal cells is higher than in cancer cells, the release of C-2028 from its nanoconjugates is decreased in these cells. Additionally, we obtained the concentration profiles of C-2028 in the selected cells treated with unbound C-2028 or nanoconjugate by the HPLC analysis. Full article

Background: The anatomical and functional changes after intravitreal dexamethasone implant (IDI) alone and combined with navigated subthreshold micropulse laser (NSML) in diabetic macular oedema (DMO) were compared. Methods: Patients with a clinically confirmed diagnosis of non-proliferative diabetic retinopathy (NPDR) and DMO were enrolled in this prospective study and were randomly assigned to two different treatment groups: thirty patients were treated with IDI (IDI group), and the other 30 patients received IDI combined with NSML treatment (combined IDI/NSML group). All patients during a 6-month follow-up underwent best corrected visual acuity (BCVA) evaluation and spectral domain optical coherence tomography (SD OCT). The main outcome measures were: BCVA, central macular thickness (CMT); (3) choroidal vascularity index (CVI), subfoveal choroidal thickness (SCHT); and time to retreatment between IDI at baseline and the second implant in both groups. Results: BCVA, CMT, and SCHT significantly decreased starting from the 1-month follow-up and CVI from 3 months in both groups. The between-group differences were significantly different from 1-month follow-up for BCVA, from 5-month follow-up for CMT and SCHT, and from 4-month follow-up for CVI. The Needed to Treat analysis indicated that six patients would have to be treated with SML after IDI in order for just one person to receive a benefit. Conclusions: the combined treatment showed good anatomical and functional outcomes for the treatment of DMO. In addition, IDI/SML seems to reduce injection frequency over time, improving patients’ quality of life and reducing the socio-economic burden. Full article

Contemporary advances in technology have allowed the transfer of knowledge from industrial laser melting systems to surgery; such an approach could increase the degree of accuracy in orbital restoration. The aim of this study was to examine the accuracy of selective laser melted PSIs (patient-specific implants) and navigation in primary orbital reconstruction. Ninety-six patients with orbital fractures were included in this study. Planned vs. achieved orbital volumes (a) and angles (b) were compared to the unaffected side (n = 96). The analysis included the overlay of post-treatment on planned images (iPlan 3.0.5, Brainlab^®, Feldkirchen, Germany). The mean difference in orbital volume between the digitally planned orbit and the postoperative orbit was 29.16 cm³ (SD 3.54, presurgical) to 28.33 cm³ (SD 3.64, postsurgical, t = 5.00, df = 95.00; p < 0.001), resulting in a mean volume difference (planned vs. postop) of less than 1 cm³. A 3D analysis of the color mapping showed minor deviations compared to the mirrored unaffected side. The results suggested that primary reconstruction in complex orbital wall fractures can be routinely achieved with a high degree of accuracy by using selective laser melted orbital PSIs. Full article

The hemispherical resonator gyroscope (HRG) has attracted the interest of the world inertial navigation community because of its exceptional performance, ultra-high reliability and its potential to be miniaturized. These devices achieve their best performance when the differences in the frequencies of the two degenerate working modes are eliminated. Mechanical treatment, laser ablation, ion-beams etching, etc., have all been applied for the frequency tuning of resonators, however, they either require costly equipment and procedures, or alter the quality factors of the resonators significantly. In this paper, we experimentally investigated for the first time the use of a chemical etching procedure to decrease the frequency splits of hemispherical resonators. We provide a theoretical analysis of the chemical etching procedure, as well as the relation between frequency splits and mass errors. Then we demonstrate that the frequency split could be decreased to below 0.05 Hz by the proposed chemical etching procedure. Results also showed that the chemical etching method caused no damage to the quality factors. Compared with other tuning methods, the chemical etching method is convenient to implement, requiring less time and labor input. It can be regarded as an effective trimming method for obtaining medium accuracy hemispherical resonator gyroscopes. Full article