Frontiers in medical technology最新文献

Objectives: To evaluate the accuracy of heart rate and respiratory rate acquired by commercially-available device cameras and software.

Methods: One-hundred and eleven subjects were enrolled at an urban academic teaching hospital in Texas. Heart rate (HR) and respiratory rate (RR) measurements were obtained using three commercially-available cameras and processed using software from Presage Technologies. These values were compared to manual counts of a three-lead ECG and end-tidal CO2 from a patient monitor.

Results: The cameras were able to capture HR in 83% of the measurements and RR in 94% of the RR measurements. Camera-acquired HR showed an extremely high correlation with R∼0.99 and a root-mean-square error (RMSE) of 1.62. Respiratory rate showed a high correlation with R∼0.91 and an RMSE of 1.71.

Conclusions: Heart rate and respiratory rate can be accurately acquired using commercially-available camera devices and software for signal processing.

[This corrects the article DOI: 10.3389/fmedt.2025.1567537.].

Background: Ventricular assist devices (VADs) are an effective treatment for end-stage heart failure and can significantly improve patients' quality of life. However, when the rotational speed of the VAD does not match the intraventricular blood volume, ventricular suction may occur. Severe suction can lead to ventricular collapse, making accurate and real-time suction detection critically important.

Methods: Two statistical features and two frequency-domain features were extracted from the pump flow signal to build a classification and regression tree (CART) model. Additionally, a secondary decision-making process was applied using a time-domain threshold.

Results: The proposed method was validated using both in vivo and in vitro experimental data. Experimental results show that, compared to existing suction detection techniques, the proposed approach not only reduces computational complexity but also achieves higher detection accuracy and enhanced algorithmic stability.

Conclusions: The proposed method provides a more efficient and reliable solution for real-time ventricular suction detection, which is crucial for the safe operation of VADs in clinical settings.

In 2025, three U.S. agencies within the Department of Health and Human Services (FDA, NIH, CDC) alongside EPA and the Departments of the Navy and Veterans Affairs, began substituting animal testing applications with reliable, human-relevant methods. The impact of this shift in public policy taking place at agencies historically bullish on animal testing is still reverberating in the United States and around the world. Here, we examine the circumstances that enabled such momentous reforms, including the role of the FDA Modernization Act 2.0 in advancing new alternative methods, collectively referred to as NAMs. We explain how animal testing, despite its poor value in predicting the safety and efficacy of drugs in humans, came to dominate drug discovery, basic sciences, and environmental toxicity assessments since the inception of the Federal Food, Drug, and Cosmetic Act (Federal FD&C Act) in 1938. Specifically, we identify critical junctures, including catastrophic government decisions, that made the overall research enterprise acutely dependent on animals, leading to the existing predicament-an indefensible 92% failure rate in translating drugs from preclinical studies to actual therapies. Notably, our analysis chronicles events through the lens of "path dependency," a social sciences phenomenon that occurs when faulty past decisions lock-in future action. Finally, we recognize that our narrative is a departure from the medical establishment account or the talking points of powerful interest groups, including some in the academic elite who continue to shore up animal-centric paradigms in drug development for reasons we also outline.

Introduction: Phantoms and reference structures are essential tools for calibration and correlative imaging in pre-clinical and research applications of X-ray-based imaging. They serve as reference standards, ensuring consistency and accuracy in imaging results. However, generating individual phantoms often involves a complex creation process, high production costs, and significant time investment.

Material and methods: Conic reference structures were 3D printed using a mixture of UV-curable resin and X-ray contrast agents. These structures were then embedded together with lung specimens of SARS-CoV-2-infected rhesus macaques in a methyl methacrylate-based solution. The polymerized blocks were scanned using propagation-based phase-contrast microCT, a method chosen for its superior ability to enhance contrast, especially in low-absorbing biological samples. Utilizing the conic reference structures, subsequently performed histological sections were co-registered into the 3D context of the microCT datasets.

Results: The produced 3D printed models were highly visible in terms of contrast and detail in both imaging methods, allowing for a precise co-registration of microCT and histological imaging.

Conclusions: The novel methodology of using contrast agents and resin in 3D printing enables the generation of customizable, contrast-specific phantoms and reference structures. These can be straightforwardly segmented from the embedding material, significantly simplifying and enhancing the workflow of multimodal imaging processes. In this study, 3D printed conic reference structures were effectively used to automate and streamline the precise multimodal fusion of microCT and histological imaging.

Objective: This study aims to evaluate the clinical efficacy of laparoscopic hiatal hernia repair (LHHR) in treating gastroesophageal reflux disease (GERD) and to through the therapeutic effect of total (360°) and partial (270°) laparoscopic fundoplication.

Methods: This retrospective observational study enrolled 100 patients, both with and without documented extra-oesophageal symptoms of GERD. Data were extracted from medical records, covering basic information, symptoms, treatments, and follow-up. Symptom relief and quality of life were assessed via GERD-Q score, Reflux Symptom Index (RSI), and EORTC QLQ-C30 scale, offering a foundation for comprehensive GERD patient management and treatment evaluation in clinical practice.

Results: The DeMeester index significantly decreased postoperatively in both the laparoscopic Nissen fundoplication (LNF) group (from 55.23 ± 25.12 to 11.45 ± 10.20, p < 0.05) and the laparoscopic Toupet fundoplication (LTF) group (from 60.51 ± 28.40 to 11.70 ± 9.65, p < 0.05). The RSI scores improved at 12 months postoperatively in both groups: LNF group (from 23.1 ± 15.4 to 13.7 ± 9.6, p < 0.05) and LTF group (from 21.9 ± 15.8 to 12.8 ± 8.2, p < 0.05). The GERD scores also improved postoperatively: LNF group (from 13 ± 5.0 to 10 ± 4.4, p < 0.05) and LTF group (from 10 ± 4.7 to 7.5 ± 4.5, p < 0.05).

Conclusion: Our report demonstrates that LHHR significantly improved GERD regarding symptom frequency, acid reflux occurrences and DeMeester score. Both LNF and LTF provide good results.

Neonatal hypoxia ischaemia (HI) affects 1-3 per 1,000 live births, is a major cause of infant mortality and morbidity, and leads to adverse long-term neurological outcomes, while reliable biomarkers are scarce. Extracellular vesicles (EVs) are small membrane vesicles released from cells and play key roles in cellular communication through the transfer of diverse cargoes, including proteins, and can be isolated from various body fluids. Here, we developed a new non-invasive method of biofluid-EV profiling, isolating EVs from eye lavage. Our data demonstrate that in a neonatal HI mouse model of mild and severe insults, significant differences are found in EV eye lavage signatures. We identified increased EV numbers and modifications in EV size profiles and EV's proteomic cargo signatures in eye lavage from HI animals compared to controls. A protein-protein interaction network analysis of the EV proteome cargoes identified enrichment in Gene Ontology and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathways in the HI groups associated with various homeostatic and disease-related pathways. The specific changes in the mild HI group included pathways for ribosome biogenesis, translation, RNA processing, gene expression, blood coagulation, innate immunity, antioxidant activity, phospholipid binding, post-synapse, cell cortex, and HIF-1 signalling. The enriched pathways only associated with the EV proteome of the severe HI group included cytoskeleton organisation, peptide cross-linking, monosaccharide biosynthesis, peroxidase activity, extrinsic component of plasma membrane, the GAIT complex, mast cell granulation, ruffle, and sealing of the nuclear envelope by the endosomal sorting complex required for transport III. Here, we report a new non-invasive method using eye lavage EV signatures to identify changes in response to HI. Our results highlight eye lavage EVs as potential clinical biomarkers for predicting changes that occur in the brain and eye due to different neonatal HI injury severities.

Background and objective: Calcific obstruction of the pulmonary conduit is a late complication of surgical implantation of a homograft in congenital patients. Percutaneous pulmonary valve implantation (PPVI) is an effective alternative to surgical repair. However, this procedure is affected by several complications, with coronary artery (CA) compression being one of the most severe. High-fidelity finite element (FE) models can provide accurate predictions but are too computationally expensive for routine use, whereas simplified models sacrifice mechanical fidelity. This study proposes a novel FE-based framework to investigate conduit pre-stenting feasibility, while aiming to balance computational efficiency with predictive accuracy within clinically relevant timelines.

Methods: A semi-automated pipeline was developed, requiring manual input only for the segmentation of computed tomography (CT), virtual stent positioning, and simulation launch. Patient-specific geometries were meshed and processed through an automated in-house script, generating ready-to-run Abaqus input files. A multifactorial CA compression risk index was introduced, integrating baseline and post-expansion distances between the pulmonary artery and CA, and their changes during the procedure. The FE simulation of the pre-stenting procedure was tested on 10 PPVI candidates, simulating CP-stent implantation. Simulation accuracy was assessed against fluoroscopy-derived stent diameters.

Results: The full simulation process required less than 10 h per case, with minimal operator workload. FE-predicted stent configuration showed strong agreement with fluoroscopic measurements ( $R^2$ = 0.87), with a mean absolute error of 3.5 $\pm$ 4.4%. Accuracy was highest in patients with calcific volumes <0.8  ${\mathrm{cm}}^3$ (error <0.5 mm). CA compression index identified 2 high-risk, 2 moderate-risk, and 6 negligible-risk patients. Peri-procedural fluoroscopy was not available for one negligible-risk patient; it excluded CA compression for the remaining negligible-risk patients (true negatives), for all moderate-risk patients, and for one high-risk patient (false positive); it highlighted CA compression for the remaining high-risk patient (true positive).

Conclusions: The proposed FE simulation framework enables patient-specific prediction of stent configuration and CA compression risk within clinically compatible timelines. The balanced trade-off between mechanical fidelity and computational efficiency supports its potential integration into pre-procedural planning of conduit pre-stenting and PPVI.