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1.
Artigo em Inglês | MEDLINE | ID: mdl-39370493

RESUMO

PURPOSE: Teleoperated Interventional Robotic systems (TIRs) are developed to reduce radiation exposure and physical stress of the physicians and enhance device manipulation accuracy and stability. Nevertheless, TIRs are not widely adopted, partly due to the lack of intuitive control interfaces. Current TIR interfaces like joysticks, keyboards, and touchscreens differ significantly from traditional manual techniques, resulting in a shallow, longer learning curve. To this end, this research introduces a novel control mechanism for intuitive operation and seamless adoption of TIRs. METHODS: An off-the-shelf medical torque device augmented with a micro-electromagnetic tracker was proposed as the control interface to preserve the tactile sensation and muscle memory integral to interventionalists' proficiency. The control inputs to drive the TIR were extracted via real-time motion mapping of the interface. To verify the efficacy of the proposed control mechanism to accurately operate the TIR, evaluation experiments using industrial grade encoders were conducted. RESULTS: A mean tracking error of 0.32 ± 0.12 mm in linear and 0.54 ± 0.07° in angular direction were achieved. The time lag in tracking was found to be 125 ms on average using pade approximation. Ergonomically, the developed control interface is 3.5 mm diametrically larger, and 4.5 g. heavier compared to traditional torque devices. CONCLUSION: With uncanny resemblance to traditional torque devices while maintaining results comparable to state-of-the-art commercially available TIRs, this research successfully provides an intuitive control interface for potential wider clinical adoption of robot-assisted interventions.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39231067

RESUMO

SIGNIFICANCE: Research on the conditions under which electronic cigarette (EC) use produces a net reduction in the population harm attributable to combusted cigarette (CC) use requires the triangulation of information from cohort(s) of smokers, non-smokers, EC users, and dual-users of all varieties. MATERIALS AND METHODS: This project utilizes data from the All of Us Research Program to contrast a panel of wellness and disease-risk indicators across a range of self-reported tobacco-use profiles, including smokers, current, and former EC users. This article focuses on the tobacco use history and current tobacco use status among All of Us participants enrolled between May 2017 and February 2023 (Registered Controlled Tier Curated Data Repository [CDR] v7). RESULTS: The present analytic sample included an unweighted total of N = 412 211 individuals with information on ever-use of both CC and EC. Among them, 155 901 individuals have a history of CC use, with 65 206 identified as current smokers. EC usage is reported by 64 002 individuals, with 16 619 being current users. Model predicted analyses identified distinct patterns in CC and EC usage across demographic and socioeconomic variables, with younger ages favoring ECs. DISCUSSION: Age was observed to significantly affect EC usage, and gender differences reveal that males were significantly more likely to use CC and/or EC than females or African Americans of any gender. Higher educational achievement and income were associated with lower use of both CC and EC, while lower levels of mental health were observed to increase the likelihood of using CC and EC products. CONCLUSION: Findings suggest the potential for the All of Us Research Program for investigation of causal factors driving both behavioral use transitions and cessation outcomes.

3.
Neural Netw ; 180: 106732, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39305783

RESUMO

Blood coagulation, which involves a group of complex biochemical reactions, is a crucial step in hemostasis to stop bleeding at the injury site of a blood vessel. Coagulation abnormalities, such as hypercoagulation and hypocoagulation, could either cause thrombosis or hemorrhage, resulting in severe clinical consequences. Mathematical models of blood coagulation have been widely used to improve the understanding of the pathophysiology of coagulation disorders, guide the design and testing of new anticoagulants or other therapeutic agents, and promote precision medicine. However, estimating the parameters in these coagulation models has been challenging as not all reaction rate constants and new parameters derived from model assumptions are measurable. Although various conventional methods have been employed for parameter estimation for coagulation models, the existing approaches have several shortcomings. Inspired by the physics-informed neural networks, we propose Coagulo-Net, which synergizes the strengths of deep neural networks with the mechanistic understanding of the blood coagulation processes to enhance the mathematical models of the blood coagulation cascade. We assess the performance of the Coagulo-Net using two existing coagulation models with different extents of complexity. Our simulation results illustrate that Coagulo-Net can efficiently infer the unknown model parameters and dynamics of species based on sparse measurement data and data contaminated with noise. In addition, we show that Coagulo-Net can process a mixture of synthetic and experimental data and refine the predictions of existing mathematical models of coagulation. These results demonstrate the promise of Coagulo-Net in enhancing current coagulation models and aiding the creation of novel models for physiological and pathological research. These results showcase the potential of Coagulo-Net to advance computational modeling in the study of blood coagulation, improving both research methodologies and the development of new therapies for treating patients with coagulation disorders.

4.
Drug Alcohol Depend ; 263: 112390, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39173221

RESUMO

INTRODUCTION: Exposure to xylazine has been associated with wounds distinct from typical injection-related skin and soft tissue infections. We sought to understand drug use and wound care practices, and treatment experiences of people who use drugs (PWUD) in a high-prevalence area of xylazine adulteration. METHODS: In August 2023, we surveyed adult PWUD reporting at least one past-year drug use-related wound across three Massachusetts syringe service programs. Using a representative illustration, participants indicated if they had experienced a xylazine wound in the past 90 days. We compared demographic, drug use factors, wound care, and medical treatment experiences among those with and without xylazine wounds. We also conducted additional content analysis of open-ended responses. RESULTS: Of the 171 respondents, 87 % (n=148) had a xylazine wound in the past 90 days. There were no statistically significant demographic differences between those with and without xylazine wounds. Among those primarily injecting (n=155), subcutaneous injection was nearly ten times more likely among people with xylazine wounds. For those with xylazine wounds (n=148), many engaged in heterogeneous wound self-treatment practices, and when seeking medical care, 74 % experienced healthcare stigma and 58 % had inadequate pain and withdrawal management. CONCLUSION: People with self-identified xylazine wounds were more likely to engage in subcutaneous injection and faced several barriers seeking medical wound treatment. Programs serving people exposed to xylazine should work to support safer injection practices, including alternatives to injecting and improving access to high-quality, effective wound care. Further study is warranted to understand the causes, promoters, and prevention of xylazine-related wounds.


Assuntos
Xilazina , Humanos , Xilazina/uso terapêutico , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Ferimentos e Lesões/epidemiologia , Contaminação de Medicamentos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Massachusetts/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/terapia
5.
Langmuir ; 40(25): 13155-13166, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38860974

RESUMO

The development of heterostructured anode materials provides an effective approach for enhancing the electrochemical performance of sodium-ion batteries (SIBs). In this work, ab initio molecular dynamics simulations and first-principles calculations are employed to investigate the Na-ion intercalation and diffusion in MXene/graphene oxide heterostructures. The influence of graphene oxidation on interlayer spacing, Na-ion diffusion kinetics, and transport mechanisms is examined at an atomic scale. It has been observed that oxygen functional groups can increase the interspacing between adjacent layers, thereby improving the initial embedding of Na ions. However, overoxidation causes an obstructive effect on the ionic conduction channels. An appropriate oxidation degree enables optimal Na-ion migration kinetics while retaining structural integrity. Our simulation results provide crucial insights into the rational design of high-performance MXene-based anodes for SIBs with excellent capacity and cycling stability.

6.
Sci Rep ; 14(1): 392, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172209

RESUMO

The pathogenesis of Acute-on-chronic liver failure (ACLF) involves several forms of cell death, such as pyroptosis, apoptosis, and necroptosis, which consist of PANoptosis. To explore PANoptosis as a regulated cell death pathway in ACLF. Firstly, a bioinformatic strategy was used to observe the role of the PANoptosis pathway in ACLF and identify differentially expressed genes related to PANoptosis. Enrichment analysis showed that PANoptosis-related pathways were up-regulated in ACLF. We screened out BAX from the intersection of pyroptosis, apoptosis, necroptosis, and DEGs. Secondly, we screened articles from literature databases related to PANoptosis and liver failure, and specific forms of PANoptosis were reported in different experimental models in vitro and in vivo. Secondly, we established a model of ACLF using carbon tetrachloride-induced liver fibrosis, followed by D-galactosamine and lipopolysaccharide joint acute attacks. A substantial release of inflammatory factors(IL-6, IL-18, TNFα, and IFNγ) and the key proteins of PANoptosis (NLRP3, CASP1, GSDMD, BAX, CASP8, CASP3, CASP7, and MLKL) were detected independently in the ACLF rats. Finally, we found that combining TNF-α/INF-γ inflammatory cytokines could induce L02 cells PANoptosis. Our study highlighted the potential role of ACLF and helps drug discovery targeting PANoptosis in the future.


Assuntos
Insuficiência Hepática Crônica Agudizada , Ratos , Animais , Insuficiência Hepática Crônica Agudizada/metabolismo , Proteína X Associada a bcl-2 , Citocinas/metabolismo , Cirrose Hepática , Fator de Necrose Tumoral alfa/metabolismo , Apoptose
7.
Mater Horiz ; 11(1): 113-133, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37856234

RESUMO

Carbon dots (CDs) are a new type of quasi-spherical and zero-dimension carbon nanomaterial with a diameter less than 10 nm. They exhibit a broad absorption spanning from the ultraviolet (UV) to visible light regions and inspire growing interests due to their excellent performance. In recent years, it was identified that the CDs embedded in various inorganic matrices (IMs) can effectively activate afterglow emission by suppressing the nonradiative transitions of molecules and protecting the triplet excitons of CDs, which hold broad application prospects. Herein, recent advances in CDs@IMs are reviewed in detail, and the interaction and luminescence mechanisms between CDs and IMs are also summarized. We highlight the synthetic strategies of constructing composites and the roles of IMs in facilitating the applications of CDs in diverse areas. Finally, some directions and challenges of future research in this field are proposed.

8.
JACS Au ; 3(8): 2291-2298, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37654575

RESUMO

Carbon dot (CD)-based luminescent materials have attracted great attention in optical anti-counterfeiting due to their excellent photophysical properties in response to ultraviolet-to-visible excitation. Hence, there is an urgent need for the general synthesis of CD-based materials with multimode luminescence properties and high stability; however, their synthesis remains a formidable challenge. Herein, CDs were incorporated into a Yb,Tm-doped YF3 matrix to prepare CDs@YF3:Yb,Tm composites. The YF3 plays a dual role, not only serving as a host for fixing rare earth luminescent centers but also functioning as a rigid matrix to stabilize the triplet state of the CDs. Under the excitation of 365 nm ultraviolet light and 980 nm near-infrared light, CDs@YF3:Yb,Tm exhibited blue fluorescence and green room-temperature phosphorescence of CDs and upconversion luminescence of Tm3+, respectively. Due to the strong protection of the rigid matrix, the stability of CDs@YF3:Yb,Tm is greatly improved. This work provides a general synthesis strategy for achieving multimode luminescence and high stability of CD-based luminescent materials and offers opportunities for their applications in advanced anti-counterfeiting and information encryption.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37027614

RESUMO

The combination of augmented reality (AR) and medicine is an important trend in current research. The powerful display and interaction capabilities of the AR system can assist doctors to perform more complex operations. Since the tooth itself is an exposed rigid body structure, dental AR is a relatively hot research direction with application potential. However, none of the existing dental AR solutions are designed for wearable AR devices such as AR glasses. At the same time, these methods rely on high-precision scanning equipment or auxiliary positioning markers, which greatly increases the operational complexity and cost of clinical AR. In this work, we propose a simple and accurate neural-implicit model-driven dental AR system, named ImTooth, and adapted for AR glasses. Based on the modeling capabilities and differentiable optimization properties of state-of-the-art neural implicit representations, our system fuses reconstruction and registration in a single network, greatly simplifying the existing dental AR solutions and enabling reconstruction, registration, and interaction. Specifically, our method learns a scale-preserving voxel-based neural implicit model from multi-view images captured from a textureless plaster model of the tooth. Apart from color and surface, we also learn the consistent edge feature inside our representation. By leveraging the depth and edge information, our system can register the model to real images without additional training. In practice, our system uses a single Microsoft HoloLens 2 as the only sensor and display device. Experiments show that our method can reconstruct high-precision models and accomplish accurate registration. It is also robust to weak, repeating and inconsistent textures. We also show that our system can be easily integrated into dental diagnostic and therapeutic procedures, such as bracket placement guidance.

10.
Med Eng Phys ; 113: 103969, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36966003

RESUMO

A miniature grinding wheel (0.85 mm diameter) was fabricated by nickel (Ni)-diamond electroplating on a thin (0.65 mm outer diameter) flexible hollow stainless steel drive shaft to remove the calcified plaque in coronary and peripheral arteries by atherectomy procedure. To coat electrically nonconductive diamond grits, the drive shaft was submerged in a pile of diamond grit during Ni electroplating. The electroplating current density and temperature were investigated for better surface finishing and Faraday efficiency. The electroplating time to obtain the designed coating thickness was modeled based on Faraday's law of electrolysis and the geometry of drive shaft, wheel, and diamond grit. To validate the miniature wheel performance in atherectomy, grinding experiments were conducted on an atherectomy cardiovascular simulator with a calcified plaque surrogate. The wheel motion, material removal rate, and wheel surface wear were studied via high-speed camera imaging and laser confocal microscopy. The grinding wheel with 80,000 rpm rotational speed had an orbital speed of 14,300 rpm around the 1.5 mm diameter plaque surrogate lumen. After grinding for 120 s, the plaque surrogate inner diameter was enlarged to 3.03 mm, and no wear or loss of diamond abrasive was observed on the grinding wheel. This study demonstrated that the proposed electroplating process for fabricating miniature grinding wheels could effectively remove the calcified plaque surrogate. This research could lead to a more effective and safer atherectomy device with sub-mm miniature diamond wheels to treat lesions deep in coronary and peripheral arteries.


Assuntos
Diamante , Galvanoplastia , Doença das Coronárias/fisiopatologia , Níquel , Angiografia Coronária/métodos , Coração
11.
J Vasc Access ; 24(4): 722-728, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34711097

RESUMO

BACKGROUND: The arteriovenous fistula (AVF) is the preferred vascular access for End Stage Renal Disease, having superior patency and lower infection risks than prosthetic graft and catheter access. When AVF dysfunction or delayed maturation does occur, the gold standard for diagnosis is the fistula angiogram (a.k.a. fistulogram). 3D ultrasound is available for obstetrical and other specialized uses, but it is cost prohibitive and has a field of view that is too small to cover the region of interest for the dialysis fistula application. We sought to develop a point of care 3D solution using freehand 2D ultrasound data acquisition. METHODS: We developed open-source software for 3D image reconstruction and projection of an angiogram-like image of the vascular access using a 2D freehand ultrasound scanner. We evaluated this software by comparing the ultrasound "sono-angiogram" images to fistulogram images in five subjects, using visual inspection and by applying the Percent of Exact Match (PEM) as a statistic test. RESULTS: The sono-angiograms showed identifiable characteristics that matched the fistulogram results in all five subjects. The PEM ranged between 42.8% and 77.0%, with Doppler and grayscale ultrasound data, showing complementary advantages and disadvantages when used for sono-angiogram image construction. Motion from freehand ultrasound acquisition was a significant source of mismatch. 3D image generation is a potential advantage with ultrasound data. CONCLUSIONS: While further work is needed to improve the accuracy with free hand scanning, fistulogram-like "sono-angiograms" can be generated using point of care 2D ultrasound. Methods such as these may be able to assist in point-of-care diagnosis in the future. The software is open-source, and importantly, the ultrasound data used are non-proprietary and available from any standard ultrasound machine. The simplicity and accessibility of this approach warrant further study.


Assuntos
Derivação Arteriovenosa Cirúrgica , Fístula , Humanos , Diálise Renal , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Ultrassonografia Doppler , Software , Grau de Desobstrução Vascular
12.
Nano Lett ; 22(13): 5127-5136, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35700100

RESUMO

Carbon dots (CDs) have aroused widespread interest in the construction of room-temperature phosphorescent (RTP) materials. However, it is a great challenge to obtain simultaneous multicolor long-wavelength RTP emission and excellent stability in CD-based RTP materials. Herein, a novel and universal "CDs-in-YOHF" strategy is proposed to generate multicolor and long-wavelength RTP by confining various CDs in the Y(OH)xF3-x (YOHF) matrix. The mechanism of the triplet emission of CDs is related to the space confinement, the formation of hydrogen bonds and C-F bonds, and the electron-withdrawing fluorine atoms. Remarkably, the RTP lifetime of orange-emissive CDs-o@YOHF is the longest among the reported single-CD-matrix composites for emission above 570 nm. Furthermore, CDs-o@YOHF exhibited higher RTP performance at long wavelength in comparison to CDs-o@matrix (matrix = PVA, PU, urea, silica). The resulting CDs@YOHF shows excellent photostability, thermostability, chemical stability, and temporal stability, which is rather favorable for information security, especially in a complex environment.


Assuntos
Carbono , Pontos Quânticos , Carbono/química , Corantes Fluorescentes/química , Fluoretos , Pontos Quânticos/química , Temperatura
13.
Stroke Vasc Neurol ; 7(6): 465-475, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35649687

RESUMO

OBJECTIVES: To integrate morphological, haemodynamic and mechanical analysis of carotid atheroma driving plaque disruption. MATERIALS AND METHODS: First, we analysed the phenotypes of carotid endarterectomy specimens in a photographic dataset A, and matched them with the likelihood of preoperative stroke. Second, laser angioscopy was used to further define the phenotypes in intact specimens (dataset B) and benchmark with histology. Third, representative vascular geometries for each structural phenotype were analysed with Computational Fluid Dynamics (CFD), and the mechanical strength of the complicated atheroma to resist penetrating forces was quantified (n=14). RESULTS: In dataset A (n=345), ulceration (fibrous cap disruption) was observed in 82% of all plaques, intraplaque haemorrhage in 68% (93% subjacent to an ulcer) and false luminal formation in 48%. At least one of these 'rupture' phenotypes was found in 97% of symptomatic patients (n=69) compared with 61% in asymptomatic patients. In dataset B (n=30), laser angioscopy redemonstrated the structural phenotypes with near-perfect agreement with histology. In CFD, haemodynamic stress showed a large pulse magnitude, highest upstream to the point of maximal stenosis and on ulceration the inflow stream excavates the necrotic core cranially and then recirculates into the true lumen. Based on mechanical testing (n=14), the necrotic core is mechanically weak and penetrated by the blood on fibrous cap disruption. CONCLUSIONS: Fibrous cap ulceration, plaque haemorrhage and excavation are sequential phenotypes of plaque disruption resulting from the chiselling effect of haemodynamic forces over unmatched mechanical tissue strength. This chain of events may result in thromboembolic events independently of the degree of stenosis.


Assuntos
Estenose das Carótidas , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/complicações , Estenose das Carótidas/complicações , Constrição Patológica/complicações , Constrição Patológica/patologia , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/cirurgia , Fibrose , Hemorragia
14.
J Ultrasound Med ; 41(11): 2755-2766, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35170801

RESUMO

OBJECTIVES: Ultrasound is useful in predicting arteriovenous fistula (AVF) maturation, which is essential for hemodialysis in end-stage renal disease patients. We developed ultrasound software that measures circumferential vessel wall strain (distensibility) using conventional ultrasound Digital Imaging and Communications in Medicine (DICOM) data. We evaluated user-induced variability in measurement of arterial wall distensibility and upon finding considerable variation we developed and tested 2 methods for semiautomated measurement. METHODS: Ultrasound scanning of arteries of 10 subjects scheduled for AVF surgery were performed. The top and bottom of the vessel wall were tracked using the Kanade-Lucas-Tomasi (KLT) feature-tracking algorithm over the stack of images in the DICOM cine loops. The wall distensibility was calculated from the change of vessel diameter over time. Two semiautomated methods were used for comparison. RESULTS: The location of points selected by users for the cine loops varied significantly, with a maximum spread of up to 120 pixels (7.8 mm) for the top and up to 140 pixels (9.1 mm) for the bottom of the vessel wall. This variation in users' point selection contributed to the variation in distensibility measurements (ranging from 5.63 to 41.04%). Both semiautomated methods substantially reduced variation and were highly correlated with the median distensibility values obtained by the 10 users. CONCLUSIONS: Minimizing user-induced variation by standardizing point selection will increase reproducibility and reliability of distensibility measurements. Our recent semiautomated software may help expand use in clinical studies to better understand the role of vascular wall compliance in predicting the maturation of fistulas.


Assuntos
Derivação Arteriovenosa Cirúrgica , Falência Renal Crônica , Humanos , Reprodutibilidade dos Testes , Diálise Renal/métodos , Software
15.
ASAIO J ; 68(3): 440-445, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34049311

RESUMO

Maintaining dialysis vascular access is a source of considerable morbidity in patients with end-stage renal disease (ESRD). High-resolution radiofrequency (RF) ultrasound vascular strain imaging has been applied experimentally in the vascular access setting to assist in diagnosis and management. Unfortunately, high-resolution RF data are not routinely accessible to clinicians. In contrast, the standard DICOM formatted B-mode ultrasound data are widely accessible. However, B-mode, representing the envelope of the RF signal, is of much lower resolution. If strain imaging could use open-source B-mode data, these imaging techniques could be more broadly investigated. We conducted experiments to detect wall strain signals with submillimeter tracking resolutions ranging from 0.2 mm (3 pixels) to 0.65 mm (10 pixels) using DICOM B-mode data. We compared this submillimeter tracking to the overall vascular distensibility as the reference measurements to see if high-strain resolution strain could be detected using open-source B-Mode data. We measured the best-fit coefficient of determination between signals, expressed as the percentage of strain waveforms that exhibited a correlation with a p value of 0.05 or less. The lowest percentage was 86.7%, and most were 90% and higher. This indicates high-resolution strain signals can be detected within the vessel wall using B-mode DICOM data.


Assuntos
Falência Renal Crônica , Humanos , Falência Renal Crônica/terapia , Ultrassonografia/métodos
16.
J Neurosurg ; 136(1): 197-204, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34087793

RESUMO

OBJECTIVE: Despite advancement of thrombectomy technologies for large-vessel occlusion (LVO) stroke and increased user experience, complete recanalization rates linger around 50%, and one-third of patients who have undergone successful recanalization still experience poor neurological outcomes. To enhance the understanding of the biomechanics and failure modes, the authors conducted an experimental analysis of the interaction of emboli/artery/devices in the first human brain test platform for LVO stroke described to date. METHODS: In 12 fresh human brains, 105 LVOs were recreated by embolizing engineered emboli analogs and recanalization was attempted using aspiration catheters and/or stent retrievers. The complex mechanical interaction between diverse emboli (elastic, stiff, and fragment prone), arteries (anterior and posterior circulation), and thrombectomy devices were observed, analyzed, and categorized. The authors systematically evaluated the recanalization process through failure modes and effects analysis, and they identified where and how thrombectomy devices fail and the impact of device failure. RESULTS: The first-pass effect (34%), successful (71%), and complete (60%) recanalization rates in this model were consistent with those in the literature. Failure mode analysis of 184 passes with thrombectomy devices revealed the following. 1) Devices loaded the emboli with tensile forces leading to elongation and intravascular fragmentation. 2) In the presence of anterograde flow, small fragments embolize to the microcirculation and large fragments result in recurrent vessel occlusion. 3) Multiple passes are required due to recurrent (15%) and residual (73%) occlusions, or both (12%). 4) Residual emboli remained in small branching and perforating arteries in cases of alleged complete recanalization (28%). 5) Vacuum caused arterial collapse at physiological pressures (27%). 6) Device withdrawal caused arterial traction (41%), and severe traction provoked avulsion of perforating and small branching arteries. CONCLUSIONS: Biomechanically superior thrombectomy technologies should prevent unrestrained tensional load on emboli, minimize intraluminal embolus fragmentation and release, improve device/embolus integration, recanalize small branching and perforating arteries, prevent arterial collapse, and minimize traction.


Assuntos
Encéfalo/cirurgia , Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Procedimentos Neurocirúrgicos/métodos , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Idoso , Arteriopatias Oclusivas/cirurgia , Autopsia , Cadáver , Catéteres , Artérias Cerebrais/patologia , Artérias Cerebrais/cirurgia , Falha de Equipamento , Humanos , Doença Iatrogênica , Embolia Intracraniana/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Stents , Trombectomia/efeitos adversos , Falha de Tratamento , Resultado do Tratamento
17.
J Vasc Access ; 23(6): 871-876, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33971754

RESUMO

INTRODUCTION: Dialysis vascular access, preferably an autogenous arteriovenous fistula, remains an end stage renal disease (ESRD) patient's lifeline providing a means of connecting the patient to the dialysis machine. Once an access is created, the current gold standard of care for maintenance of vascular access is angiography and angioplasty to treat stenosis. While point of care 2D ultrasound has been used to detect access problems, we sought to reproduce angiographic results comparable to the gold standard angiogram (fistulogram) using ultrasound data acquired from a conventional 2D ultrasound scanner. METHODS: A 2D ultrasound probe was used to acquire a series of cross sectional images of the vascular access including arteriovenous anastomosis of a subject with a radio-cephalic fistula. These 2D B-mode images were used for 3D vessel reconstruction by binary thresholding to categorize vascular versus non-vascular structures followed by standard image segmentation to select the structure representative of dialysis vascular access and morphologic filtering. Image processing was done using open source Python Software. RESULTS: The open source software was able to: (1) view the gold standard fistulogram images, (2) reconstruct 2D planar images of the fistula from ultrasound data as viewed from the top, analogous to computerized tomography images, and (3) construct a 2D representation of vascular access similar to the angiogram. CONCLUSION: We present a simple approach to obtain an angiogram-like representation of the vascular access from readily available, non-proprietary 2D ultrasound data in the point of care setting. While the sono-angiogram is not intended to replace angiography, it may be useful in providing 3D imaging at the point of care in the dialysis unit, outpatient clinic, or for pre-operative planning for interventional procedures. Future work will focus on improving the robustness and quality of the imaging data while preserving the straightforward freehand approach used for ultrasound data acquisition.


Assuntos
Derivação Arteriovenosa Cirúrgica , Falência Renal Crônica , Humanos , Diálise Renal , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Ultrassonografia/métodos , Angiografia , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/terapia
18.
J Vasc Access ; 23(2): 304-308, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32985326

RESUMO

We used novel open source software, based on an ultrasound speckle tracking algorithm, to examine the distensibility of the vessel wall of the inflow artery, anastomosis, and outflow vein before and after two procedures. An 83-year-old white man with a poorly maturing radio-cephalic fistula received an angioplasty at the anastomosis followed by branch ligation 28 days later. Duplex Doppler measurements corroborated the blood flow related changes anticipated from the interventions. The experimental distensibility results showed that it is technically feasible to measure subtle vessel wall motion changes with high resolution (sub-millimeter) using standard Digital Imaging and Communications in Medicine (DICOM) ultrasound data, which are readily available on conventional ultrasound scanners. While this methodology was originally developed using high resolution radiofrequency from ultrasound data, the goal of this study was to use DICOM data, which makes this technology accessible to a wide range of users.


Assuntos
Derivação Arteriovenosa Cirúrgica , Fístula , Idoso de 80 Anos ou mais , Angioplastia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Humanos , Masculino , Diálise Renal/métodos , Software , Resultado do Tratamento , Grau de Desobstrução Vascular
19.
ASAIO J ; 68(1): 112-121, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34380948

RESUMO

This study presents an edge detection and speckle tracking (EDST) based algorithm to calculate distensibility as percentage of change of vessel diameter during cardiac cycles. Canny edge detector, Vandermonde matrix representation, Kanade Lucas Tomasi algorithm with pyramidal segmentation, and penalized least squares technique identifies the vessel lumen edge, track the vessel diameter, detrend the signal and find peaks and valleys when the vessel is fully distended or contracted. An upper extremity artery from 10 patients underwent an ultrasound examination as part of preoperative evaluation before arteriovenous fistula surgery. Three studies were performed to evaluate EDST with automatic peak and valley selection versus manual speckle selection of expert users using manual peak and valley selection. Results demonstrate the effectiveness of the proposed methodology, to obtain comparable results as those obtained by expert-users, and considerably reducing the variability associated with external factors such as excessive motion, fluctuations in stroke volume, beat-to-beat blood pressure changes, breathing cycles, and arm-transducer pressure.


Assuntos
Algoritmos , Derivação Arteriovenosa Cirúrgica , Artérias Carótidas/diagnóstico por imagem , Humanos , Movimento (Física) , Ultrassonografia
20.
IEEE Robot Autom Lett ; 6(3): 4664-4671, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34532570

RESUMO

Novel severe acute respiratory syndrome coronavirus 2 (COVID-19) has become a pandemic of epic proportions, and global response to prepare health systems worldwide is of utmost importance. 2-dimensional (2D) lung ultrasound (LUS) has emerged as a rapid, noninvasive imaging tool for diagnosing COVID-19 infected patients. Concerns surrounding LUS include the disparity of infected patients and healthcare providers, and importantly, the requirement for substantial physical contact between the patient and operator, increasing the risk of transmission. New variants of COVID-19 will continue to emerge; therefore, mitigation of the virus's spread is of paramount importance. A tele-operative robotic ultrasound platform capable of performing LUS in COVID-19 infected patients may be of significant benefit, especially in low- and middle-income countries. The authors address the issues mentioned above surrounding the use of LUS in COVID-19 infected patients and the potential for extension of this technology in a resource-limited environment. Additionally, first-time application, feasibility, and safety were validated in healthy subjects. Preliminary results demonstrate that our platform allows for the successful acquisition and application of robotic LUS in humans.

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