Search Results (160)

Computer-assisted surgical simulation (CASS) in craniomaxillofacial (CMF) surgery is traditionally performed using a computer interface (CI) with a two-dimensional monitor, while the adoption of immersive virtual reality (VR) remains limited. This study examined how low-dose (LD) and high-dose (HD) cone beam computed tomography (CBCT) imaging modes influence image quality and usability across both CI and VR environments. Five CMF radiologists rated CBCT views and 3D-segmented models on a 0–4 Likert scale, and intra- and interobserver agreement was calculated. VR usability was further assessed using the NASA Task Load Index and follow-up interviews. LD imaging performed comparably to HD in both interfaces, with slightly higher scores for CBCT views in LD mode. For 3D models, HD scored marginally higher in CI, whereas LD performed slightly better in VR. Observer agreement ranged from fair to excellent, and VR demonstrated reliability like CI. NASA-TLX results indicated reductions in mental and temporal demand, along with decreased effort and frustration during VR use, suggesting diminishing cognitive and emotional strain over time. In this pilot study, the findings suggest that LD CBCT may be feasible for selected CMF CASS applications and that VR offers an immersive and user-friendly alternative without compromising diagnostic reliability, supporting its potential role in future surgical planning. Full article

Background/Objectives: We evaluated whether resin infiltration treatment of demineralized enamel improves shear bond strength (SBS). Methods: Thirty permanent bovine incisor teeth were assigned randomly into three groups (n = 10 per group): control group, demineralized enamel pretreated with ICON^® resin infiltrant (Exp1 group), and demineralized enamel without pretreatment (Exp2). Demineralization was induced using a pH 4.5 solution for 21 days and was monitored using swept-source optical coherence tomography on days 0, 7, 14, and 21. The lesion depth (LD) was quantified and evaluated using ImageJ software. In the Exp1 group, ICON^® was applied prior to bracket bonding; no pretreatment was applied in the Exp2 group. In all groups, brackets were bonded using Super-Bond/Clear fluoride-free self-cure adhesive resin (4-META/MMA-TBB, Sun Medical) following Phosphoric acid (65%; Red Activator, Sun Medical). After debonding, enamel surfaces were evaluated to determine the adhesive remnant index (ARI). Results: No significant difference (p = 0.631) was noted in LD between Exp1 and Exp2 groups. The SBS values significantly differed (p < 0.05) between the control (4.1 ± 1.0 MPa) and Exp1 (5.5 ± 1.4 MPa) groups and between the Exp1 and Exp2 (3.8 ± 1.3 MPa) groups. However, SBS did not differ significantly between the control and Exp2 groups. Furthermore, ARI scores showed no significant difference between the control and Exp1 groups, whereas the Exp2 group recorded significantly elevated ARI scores relative to the control group (p = 0.0127). Conclusions: These findings suggest that resin infiltration with ICON^® may improve bracket adhesion on demineralized enamel. Full article

Background/Objectives: Arterial hypertension might lead to serious organ damage and complications like hypertensive retinopathy. The retina is the only place in the human body where microscopic blood vessels can be directly investigated. This enables early diagnosis of arterial hypertension-mediated organ damage. Untreated hypertensive retinopathy leads to vision loss in its advanced stages. There are many methods of assessing changes in the arterioles; however, the most accurate is adaptive optics (RTX1™ device with AODetectArtery software, ver. 3.0., Imagine Eyes, Orsay, France). It provides a resolution of 1.6 μm, which is superior to conventional imaging techniques. Optical coherence tomography angiography can serve as an early, minimally invasive marker of microvascular damage. Across the studies analyzed, the WLR (Wall-to-Lumen Ratio) exhibited significantly higher values when comparing individuals with hypertensive retinopathy to normotensives (0.31 vs. 0.26). The main aim of this review is to present the application of adaptive optics in the early diagnosis of hypertensive retinopathy. Methods: The search strategy included 267 original studies, among which 12 were selected to be described and analyzed in this review based on criteria including original research and studies performed on humans with hypertensive retinopathy. Results: RTX1™ enables the assessment of arterial parameters such as the Wall Thickness (WT), Lumen Diameter (LD), Outer Diameter (OD), Wall-to-Lumen Ratio (WLR) and Wall Cross Sectional Area (WCSA). These parameters differ depending on the arterial hypertension. The WLR was identified to be the parameter that differs in the vast majority of analyzed studies when comparing hypertensive patients to normotensive patients. Vascular parameters were also found to change depending on different organisms’ states, treatment applications and etiological causes of disease. Furthermore, changes in retinal arterial parameters were associated with increased cardiovascular risk in observational studies. RTX1™ was also identified to provide very good intra- and interobserver variability. Conclusions: RTX1™ is a valuable tool in the examination of arterial vessels and in establishing associations between retinal vascular parameters and a patient’s clinical state. Full article

Human milk fat globules (MFGs)’ size characterization is key for evaluating milk quality and processing effects. Laser diffraction (LD) is widely used for particle size analysis but provides limited morphological information. This study applied image-based morphometric analysis (IBMA) to characterize MFGs’ size and shape distributions in human milk and compared the results with LD measurements. Milk samples from 12 women delivering term and preterm infants were analyzed. LD was performed using a Mastersizer 3000 (Malvern Panalytical, Malvern, UK) and IBMA using a Morphologi 4 (Malvern Panalytical, Malvern, UK), acquiring 2D images at 20× magnification covering particle sizes from ~1.5 to 130 µm. IBMA classified MFGs as individual particles (IP) (HS circularity ≥ 0.920; circle equivalent diameter < 25 µm) or agglomerates (HS circularity < 0.920; solidity < 0.970), extracting descriptors including circularity, elongation, and solidity. IP predominated, while agglomerates represented ~15% of particles. Number-mean diameters (D[1,0]) were 4.91 µm (total), 4.36 µm (IP), and 8.00 µm (agglomerates). Volume-weighted particle diameters (D[4,3]) were 7.21 µm for IP and 14.02 µm for agglomerates. The highest level of agreement between methods was observed for IP D[4,3], although minor differences may be clinically relevant. IBMA and LD provide complementary information; however, IBMA uniquely enables the characterization of MFG structural organization, including the identification of agglomerates, which cannot be resolved by LD. This added level of structural detail may have important implications for understanding the digestibility of human milk, particularly in preterm populations. Full article

This paper presents a Load-Dependent Multimodal Vibration Signal Enhancement and Fusion Framework (LD-MVSEFF) for load-specific condition monitoring, building on the Customised Load Adaptive Framework (CLAF). The proposed approach enhances the classification of CLAF load-dependent subclasses, namely, Healthy, Mild, Moderate, and Severe, by integrating complementary information from raw vibration signals and encoded signal representations. Three input channels are employed, combining time–frequency domain features with Continuous Wavelet Transform (CWT) and Gramian Angular Difference Field (GADF) image encodings, with each channel independently trained and evaluated to identify its most effective classifiers. To address the reduced separability of the Mild and Moderate fault subclasses under varying load conditions, a weighted decision-fusion strategy is introduced, assigning classifier contributions according to their class-specific strengths. Experimental evaluation over five runs demonstrates high and stable performance, with the best configuration achieving an overall accuracy of 99.04% ± 0.22% and an average training time of 18 min and 30 s. The results confirm the effectiveness of LD-MVSEFF as a robust multimodal methodology for load-specific condition monitoring. Full article

Objective: This prospective study investigated the use of H-scan ultrasound (US) imaging as a novel component of a multiparametric radiomic analysis framework for characterizing human breast cancer response to neoadjuvant chemotherapy (NAC) before and early after treatment initiation. Methods: Thirty breast cancer patients scheduled for NAC were scanned using a clinical US system (Logiq E9, GE HealthCare) equipped with a 9L-D linear array transducer. Radiofrequency (RF) data was obtained at baseline (pre-NAC) and after 10% and 30% of the complete dose of chemotherapy. The RF data was analyzed by a bank of 256 frequency-shifted bandpass filters to form H-scan US frequency images. Grayscale texture features were extracted from both B-scan and H-scan US images. In addition, US attenuation coefficient and speckle statistics based on the Nakagami and Burr distributions were estimated from the RF data. Data classification of tumor and peri-tumoral regions was performed using a novel three-dimensional (3D) score map based on support vector machine (SVM) modeling. Unlike conventional classifiers that report only a single prediction score, a 3D score map provides a visual representation of the classifier decision space, enabling interpretation of class separation and treatment-induced shifts in multiparametric US measurements. Results: The dataset was split into 10 disjoint partitions (90% training, 10% testing) to compute area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy measures. Actual patient response to NAC was assessed at surgery and categorized as either pathologic complete response (pCR) or non-pCR. Multiparametric US and data classification results at pre-NAC found AUC values of 0.78 after using only tumor information (p < 0.01), which increased to 0.81 with inclusion of peri-tumoral information (p < 0.01). Significant differences in multiparametric US measures from both cancer response types was found after integration of patient data collected at 10% completion of the NAC regimen (i.e., first NAC cycle), yielding an improved AUC of 0.86 (p < 0.001). Conclusions: Multiparametric US imaging with radiomic features from both the tumor and peri-tumoral regions is a promising noninvasive approach for monitoring early breast cancer response to NAC. Full article

Background/Objectives: Assessing structural damage in pediatric sacroiliitis is challenging, necessitating radiation-free alternatives to computed tomography (CT). This study evaluated the diagnostic performance of advanced MRI sequences—3D-MENSA (Multi-Echo in Steady-State Acquisition), 3D-MERGE (Multiple-Echo Recombined Gradient Echo), and Zero Echo Time (ZTE)—against conventional T1-weighted sequences for detecting structural lesions. Low-dose computed tomography (LDCT) served as the reference standard. A secondary objective was to qualitatively assess the visibility of active inflammatory lesions and fat metaplasia. Methods: In this cross-sectional study, 23 pediatric patients with enthesitis-related arthritis (ERA) were included. To adhere strictly to radiation safety principles, the study used pre-existing ldCT datasets from a clinical cohort as the reference standard. No new CT scans were performed for this study. Structural lesions (erosions, sclerosis, and joint-space changes) were independently scored by two blinded radiologists. Interobserver agreement was assessed using intraclass correlation coefficients (ICC). Results: Advanced sequences (ZTE, 3D-MENSA, 3D-MERGE) demonstrated high agreement with ldCT for erosion detection (ICC range: 0.924–0.998) and significantly outperformed conventional T1-weighted MRI (ICC: 0.707). 3D-MENSA provided distinct contrast, effectively differentiating the ligamentous component of the sacroiliac joint from both the synovial component and the adjacent bone cortex. Qualitatively, 3D-MENSA also identified bone marrow edema and fat metaplasia, which cannot be visualized by ZTE or ldCT. Conclusions: 3D-MENSA and 3D-MERGE enable comprehensive evaluation of structural sacroiliitis lesions in pediatric patients with diagnostic accuracy comparable to ldCT. Specifically, 3D-MENSA demonstrates the potential to detect both active and chronic lesions in a single, rapid, radiation-free acquisition. These findings suggest that it should be considered for routine pediatric imaging protocols. Full article

Purpose: The present study aimed to assess the radiation dose associated with low-dose (LD) CT pelvimetry compared with conventional radiography and to evaluate the adequacy of the resulting image quality. Methods: The absorbed dose was measured using thermoluminescent dosimeters positioned in an anthropomorphic female phantom, including uterine locations, to estimate the fetal dose. Conventional radiographic pelvimetry and LD-CT pelvimetry were performed using clinically implemented protocols. Effective dose was calculated using Monte Carlo–based modeling applying acquisition parameters and retrospective patient dose registry data. Image quality of LD-CT pelvimetry was independently evaluated in 14 consecutive clinical cases using a four-point ordinal scale. Results: LD-CT pelvimetry reduced the mean absorbed pelvic dose by approximately 50% compared with conventional pelvimetry (0.18 vs. 0.39 mGy) and decreased estimated fetal dose by 40% (0.21 vs. 0.37 mGy). These estimates were based on standardized single acquisitions and did not incorporate additional radiation from retakes commonly observed in conventional practice. CT demonstrated substantially more homogeneous dose distribution, whereas conventional pelvimetry exhibited marked heterogeneity with peak values up to 2.3 mGy. The maternal effective dose was lower for LD-CT (0.16 mSv) than for conventional pelvimetry (0.36 mSv); inclusion of retakes increased the conventional effective dose to 0.71 mSv. All CT examinations were diagnostically adequate, and no recalls were required. Conclusions: Optimized low-dose CT pelvimetry significantly reduces radiation dose compared with conventional radiographic pelvimetry while maintaining reliable diagnostic image quality. These results support the clinical adoption of CT-based pelvimetry as a dose-efficient and reproducible alternative to conventional techniques. Full article

Standard SAM-based approaches in medical imaging typically rely on explicit geometric prompts, such as bounding boxes or points. However, these rigid spatial constraints are often insufficient for capturing the complex, deformable boundaries of medical structures, where localization noise easily propagates into segmentation errors. To overcome this, we propose the Localization Distillation-Enhanced Feature Prompting SAM (LDFSAM), a novel framework that shifts from discrete coordinate inputs to a latent feature prompting paradigm. We employ a lightweight prompt generator, refined via Localization Distillation (LD), to inject multi-scale features into the SAM decoder as complementary Dense Feature Prompts (DFPs) and Sparse Feature Prompts (SFPs). This effectively guides segmentation without explicit box constraints. Extensive experiments on four public benchmarks (3D CBCT Tooth, ISIC 2018, MMOTU, and Kvasir-SEG) demonstrate that LDFSAM outperforms both prior SAM-based baselines and conventional networks, achieving Dice scores exceeding 0.91. Further validation on an in-house cohort demonstrates its robust generalization capabilities. Overall, our method outperforms both prior SAM-based baselines and conventional networks, with particularly strong gains in low-data regimes, providing a reliable solution for automated medical image segmentation. Full article

Background/Objectives: Ultra-low-dose computed tomography (ULD-CT) enables substantial radiation reduction compared with routine low-dose computed tomography (LD-CT), but its quantitative reliability across lung imaging biomarkers remains insufficiently characterized. This study aimed to assess the agreement and reliability of quantitative pulmonary imaging biomarkers between paired ULD-CT and LD-CT examinations. Methods: In this prospective study, 48 patients who underwent paired LD-CT and ULD-CT on the same day were analyzed. Whole-lung quantitative biomarkers were categorized into density-derived indices, airway structural metrics, and voxel-based functional biomarkers. Agreement between LD-CT and ULD-CT was evaluated using Bland–Altman analysis and Pearson correlation. Results: Density-based biomarkers demonstrated high concordance, strong correlations, and small systematic biases, indicating robust dose stability. Airway structural metrics showed clinically acceptable agreement with near-perfect reproducibility for cluster-based indices. Voxel-based functional biomarkers exhibited greater dose sensitivity but preserved consistent directional bias. Total lung volume showed excellent reproducibility with minimal bias. Conclusions: ULD-CT enables reliable quantitative lung imaging with clinically acceptable agreement across major biomarker domains, supporting its use as a dose-efficient platform for longitudinal and screening applications. Full article

Unmanned Aerial Spraying Systems (UASS) has rapidly advanced precision crop protection. However, the spray performance of UASSs is influenced by nozzle atomization, rotor-induced airflow, and external environmental conditions. These factors cause strong spatiotemporal coupling and high uncertainty. As a result, visualization-based monitoring techniques are now essential for understanding these dynamics and supporting spray modeling and drift-mitigation design. This review highlights developments in spray visualization technologies along the “droplet–airflow–target” chain mechanism in UASS spraying. We first outline the physical fundamentals of droplet formation, liquid-sheet breakup, droplet size distribution, and transport mechanisms in rotor-induced flow. Dominant processes are identified across near-field, mid-field, and far-field scales. Next, we summarize major visualization methods. These include optical imaging (PDPA/PDIA, HSI, DIH), laser-based scattering and ranging (LD, LiDAR), and flow-field visualization (PIV). We compare their spatial resolution, measurement range, 3D reconstruction capabilities, and possible sources of error. We then review wind-tunnel trials, field experiments, and point-cloud reconstruction studies. These studies show how downwash flow and tip vortices affect plume structure, canopy disturbance, and deposition patterns. Finally, we discuss emerging intelligent analysis for large-scale monitoring—such as image-based droplet recognition, multimodal data fusion, and data-driven modeling. We outline future directions, including unified feature systems, vortex-coupled models, and embedded closed-loop spray control. This review is a comprehensive reference for advancing UASS analysis, drift assessment, spray optimization, and smart support systems. Full article

We aimed to validate the feasibility of combining ultra-widefield (UWF) fundus photography with targeted swept-source optical coherence tomography (SS-OCT) for clinical decision-making regarding a prophylactic laser therapy. For this purpose we enrolled 119 patients (135 eyes) who, basis on fundus examination, were eligible for prophylactic photocoagulation of degenerative retinal lesions. Eyes were classified into two groups: (1) justified laser, when SS-OCT confirmed vitreoretinal traction and/or subretinal fluid beneath the neurosensory retina; and (2) non-justified laser, when SS-OCT did not confirm these criteria. Using this SS-OCT-guided UWF approach, we found that 25.1% of eyes that initially qualified for laser based on clinical examination did not meet the SS-OCT criteria. Patients in the justified laser group were significantly younger than those in the non-justified group. Horseshoe retinal tears, lattice degeneration and snail-track degenerations, multiple lesions, and lesions located in the far and mid-periphery were significantly more frequent in the justified laser group than in the non-justified group. By contrast, the prevalence of operculated holes, bilateral lesions, and degenerative lesions in patients with a retinal detachment in the fellow eye did not differ between groups. Our findings suggest the SS-OCT-guided UWF imaging may refine patient selection for prophylactic laser therapy. Full article

The epidermal cells of bracts, petals and sepals of Ornithogalum umbellatum L. (Star-of-Bethlehem, Asparagaceae) contain lipotubuloids, complex aggregates of lipid droplets (LDs) enmeshed by bundles of microtubules (MTs). We investigated lipotubuloid organization and stability through the transient expression of GFP fusion proteins targeted to different subcellular structures and with immunofluorescence and transmission electron microscopy (TEM). Live cell imaging confirmed that lipotubuloids contain LDs, organelles including endomembranes, mitochondria and peroxisomes, a tonoplast-defined vacuole, and that they move through actin microfilament-based streaming. Intriguingly, the different microscopy modes used showed different patterns of MT organization in the lipotubuloid. While MT sheets and bundles were visible by TEM, few MTs were seen with fusion proteins and immunofluorescence. Oryzalin-based MT depolymerization experiments suggest a possible resolution for this paradox: TEM showed that lipotubuloid MTs resisted depolymerization, even after 20 h in oryzalin, while MT polymerization was visible in lipotubuloids with fusion proteins during oryzalin wash-out. These results suggest that the Ornithogalum lipotubuloids contain hyperstable MTs, possibly formed with microtubule-associated proteins (MAPs) that normally occlude fusion protein and antibody binding sites. Full article

Objective: Chest computed tomography (CT) is a key component of the diagnostic assessment of people with cystic fibrosis (PwCF) and is increasingly replacing chest radiography. Due to improvements in life expectancy, radiation exposure has become a growing concern in PwCF. Photon-counting CT (PCCT) has the potential to reduce the risk of radiation-induced malignancies while maintaining diagnostic accuracy. This study aimed to compare the radiation dose and image quality of low-dose high-resolution (LD-HR) and ultra-low-dose high-resolution (ULD-HR) CT protocols using PCCT in PwCF. Methods: This retrospective study included 72 PwCF, with 36 undergoing a LD-HR chest CT protocol and 36 receiving an ULD-HR protocol on a PCCT. The radiation dose and image quality were assessed by comparing the effective dose and signal-to-noise ratio (SNR). Three blinded radiologists evaluated the overall image quality, sharpness, noise, and assessability of the bronchi, bronchial wall thickening, and bronchiolitis using a five-point Likert scale. Results: The ULD-HR PCCT protocol reduced radiation exposure by approximately 65% compared with the LD-HR PCCT protocol (median effective dose: 0.19 vs. 0.55 mSv, p < 0.001). While LD-HR images were consistently rated higher than ULD-HR images (p < 0.001), both protocols maintained diagnostic significance (median image quality rating of “4-good”). The average SNR of the lung parenchyma was significantly lower with ULD-HR PCCT compared to LD-HR PCCT (p < 0.001). Conclusions: ULD-HR PCCT significantly reduced radiation exposure while maintaining good diagnostic image quality in PwCF. The effective dose of ULD-HR PCCT is only twice that of a two-plane chest X-ray, making it a viable low-radiation alternative for routine imaging in PwCF. Full article

In China, bites caused by the Naja atra and Deinagkistrodona acutus are the most common types of snakebites. While the functional characteristics of the two venom components have been well documented, their in vivo metabolic pathways, target organ distribution patterns, and dynamic pharmacokinetic profiles remain less explored. This study established a murine envenoming model through CY7-SE labeling of Naja atra and Deinagkistrodon acutus venoms. The real-time in vivo absorption and biodistribution of venoms were dynamically monitored via fluorescence imaging, with subsequent proteomic profiling to characterize organ-specific toxin targeting patterns. Gel filtration chromatography and HPLC analyses validated labeling efficiency at ratios of 0.1 mg CY7-SE per 1 mg Naja atra venom and 0.075 mg CY7-SE per 1 mg Deinagkistrodon acutus venom, with electrophoretic confirmation of protein integrity and preserved 740 nm fluorescence excitation. Acute toxicity assays demonstrated no significant difference in LD₅₀ lethality between labeled and native venoms (p > 0.05). The intoxication models revealed species-specific pathophenotypes, i.e., CY7-Naja atra venom induced systemic weakness, tachypnea, and inflammatory necrosis in lung, myocardium, and liver, whereas CY7-Deinagkistrodon acutus venom provoked hemorrhagic diathesis. Both models exhibited marked leukocytosis, transaminitis, and elevated creatinine levels (p < 0.05). Fluorescence tracing uncovered distinct biodistribution kinetics: Deinagkistrodon acutus venom achieved peak organ accumulation at 3 h with rapid dissemination (24 h injection-site retention: 12.61%), contrasting with Naja atra venom’s delayed 6 h peak and prolonged renal sequestration (24 h injection-site retention: 60.9%). Target organ proteomic profiling identified Deinagkistrodon acutus-enriched thrombin-like enzymes and metalloproteinases in lung/liver/spleen, while Naja atra venom predominantly accumulated renal acidic phospholipase A₂ and weakly neurotoxic NNAM2. Full article