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1.
Nat Commun ; 15(1): 1107, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321061

RESUMO

Hierarchical compartmentalization, a hallmark of both primitive and modern cells, enables the concentration and isolation of biomolecules, and facilitates spatial organization of biochemical reactions. Coacervate-based compartments can sequester and recruit a large variety of molecules, making it an attractive protocell model. In this work, we report the spontaneous formation of core-shell cell-sized coacervate-based compartments driven by spontaneous evaporation of a sessile droplet on a thin-oil-coated substrate. Our analysis reveals that such far-from-equilibrium architectures arise from multiple, coupled segregative and associative liquid-liquid phase separation, and are stabilized by stagnation points within the evaporating droplet. The formation of stagnation points results from convective capillary flows induced by the maximum evaporation rate at the liquid-liquid-air contact line. This work provides valuable insights into the spontaneous formation and maintenance of hierarchical compartments under non-equilibrium conditions, offering a glimpse into the real-life scenario.


Assuntos
Células Artificiais , Fenômenos Físicos , Tamanho Celular , Veias
3.
Microsurgery ; 44(2): e31148, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38343011

RESUMO

BACKGROUND: In breast reconstruction with free flaps, retrograde venous anastomosis into the internal mammary vein (IMV) is often unavoidable. Utility of a crossing vein between the right and left IMV, one of the anatomical foundations which make retrograde flow possible, has been reported but only with a few detailed features. This study evaluated the presence, actual location, and diameter of the crossing veins using preoperative imaging such as contrast-enhanced computed tomography (CECT), or contrast-enhanced magnetic resonance imaging (CEMRI). Moreover, this is a preliminary non-invasive study to clarify these processes on a larger scale. METHODS: We included 29 cases of unilateral breast reconstruction performed between July 2018 and September 2023 at our institution using unipedicled or bipedicled free deep inferior epigastric artery perforator (DIEP) flaps with retrograde venous anastomosis to only one IMV at the level of anastomosis. No congestion or necrosis was observed. In the final 24 cases with sufficient imaging coverage of preoperative contrast-enhanced images (15 CECT and 9 CEMRI), the crossing veins of IMVs were detected and the number, localization, and diameter were measured. RESULTS: In 20 cases of 24 images, the crossing veins between IMVs were completely identified (83%). In 18 of the cases, only one crossing vein was established immediately ventral to the xiphoid process, averaging 19.3 ± 7.18 mm caudal to the fibrous junction between the sternal body and xiphoid process. The average diameter of the veins was 1.57 ± 0.42 mm. In two other cases, the second crossing vein originated on the dorsal surface of the sternum, but it was a very thin vein of about 0.4 mm. Three images indicated incomplete identification of the crossing vein at the xiphoid process, and in one case, no crossing vein was observed between bilateral IMVs. CONCLUSION: The contrast-enhanced imaging study revealed an anatomic feature that the crossing veins (about 1.5 mm in diameter) connecting the right and left IMVs are located just ventral to the xiphoid process. Furthermore, the crossing veins can be identified on contrast-enhanced images, and refinement of this method is expected to lead to future non-invasive anatomical investigations in an even larger number of cases.


Assuntos
Retalhos de Tecido Biológico , Mamoplastia , Retalho Perfurante , Humanos , Veias/diagnóstico por imagem , Veias/cirurgia , Mamoplastia/métodos , Retalhos de Tecido Biológico/cirurgia , Tomografia Computadorizada por Raios X , Imageamento por Ressonância Magnética , Artérias Epigástricas/diagnóstico por imagem , Artérias Epigástricas/cirurgia , Retalho Perfurante/irrigação sanguínea
4.
Medicine (Baltimore) ; 103(7): e36923, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363945

RESUMO

RATIONALE: Klippel-Trenaunay syndrome (KTS) is a rare congenital venous malformation, it had been found to be caused by mutations of the phosphatidylinositol 4, 5-diphosphate 3-kinase catalytic subunit alpha (PIK3CA) gene. Currently KTS is defined as a triad of skin wine pigmented spots, varicose veins and malformations of the lower extremities, and hypertrophy of bone and soft tissue, involving urinary system up to 6% to 30%. When the urinary system is involved, KTS is often presented as painless massive gross hematuria. PATIENT CONCERNS: This article describes a woman who was hospitalized with painless massive gross hematuria. Physical examination revealed significant hypertrophy of the right lower limb with varicose veins, port-wine stains in the skin, and right perineal hemangiomatous changes with swelling. The patient was admitted to hospital 4 times for repeated hematuria and infection. DIAGNOSES: By physical examination, CT urography, ureteroscopy and cystoscopy, the patient was diagnosed to have Klippel-Trenaunay syndrome, involving the urinary system. INTERVENTIONS: The patient hematuria improved after multiple indwelling D-J tubes and anti-inflammatory treatment. OUTCOMES: The final symptoms of hematuria improved significantly, follow-up so far has not recurred. LESSONS: This case presents the possibility of painless gross hematuria with KTS. Most of patients can be improved by conservative treatment. Cystoscopic laser therapy is the preferred treatment for poor bleeding control. Cystectomy and nephrectomy should be considered when life-threatening.


Assuntos
Síndrome de Klippel-Trenaunay-Weber , Varizes , Feminino , Humanos , Síndrome de Klippel-Trenaunay-Weber/complicações , Síndrome de Klippel-Trenaunay-Weber/diagnóstico , Hematúria/etiologia , Veias/anormalidades , Varizes/complicações , Hipertrofia
5.
J Clin Apher ; 39(1): e22106, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38334167

RESUMO

INTRODUCTION: Donor vein assessment for the selection of good quality veins is crucial for a successful apheresis procedure. This study intends to find out the effectiveness of a vein assessment scoring tool (VST) used and found to be effective in selecting whole blood donors to reduce the difficulty in identifying good quality veins for the plateletpheresis procedure. MATERIALS AND METHODS: This was a prospective observational study on platelet apheresis donors with the application of a VST consisting of three vein descriptor parameters (vein visibility, vein palpability, and vein size) with 5 Likert-type responses constituting a score of 0-12 for each arm. Two vein assessors independently evaluated the vein in both arms and marked their responses blinded from each other as well from the principal investigator. The scores were then calculated and analyzed at the end of the study for their association with phlebotomy and procedural outcomes. RESULTS: A total of 190 donors were recruited. The mean scores for the arms with successful and failed phlebotomy were 9.1 and 9.4 (SD 2.3), respectively. The intra-class correlation Alpha Cronbach value was 0.834 and 0.837 for total scoring in the left arm and right arm, respectively, between the two assessors. Scores neither showed a correlation with other outcomes like low flow alarms, hematoma formation, number of phlebotomy attempts, and procedure completion. CONCLUSION: The study showed that the vein score tool did not truly predict the phlebotomy outcome in apheresis donors, though there was a good degree of inter-assessor reliability.


Assuntos
Plaquetoferese , Veias , Humanos , Plaquetoferese/métodos , Reprodutibilidade dos Testes , Doadores de Sangue , Flebotomia/métodos
6.
Int J Mol Sci ; 25(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338837

RESUMO

One of the early symptoms of chronic venous disease (CVD) is varicose veins (VV) of the lower limbs. There are many etiological environmental factors influencing the development of chronic venous insufficiency (CVI), although genetic factors and family history of the disease play a key role. All these factors induce changes in the hemodynamic in the venous system of the lower limbs leading to blood stasis, hypoxia, inflammation, oxidative stress, proteolytic activity of matrix metalloproteinases (MMPs), changes in microcirculation and, consequently, the remodeling of the venous wall. The aim of this review is to present current knowledge on CVD, including the pathophysiology and mechanisms related to vein wall remodeling. Particular emphasis has been placed on describing the role of inflammation and oxidative stress and the involvement of extracellular hemoglobin as pathogenetic factors of VV. Additionally, active substances used in the treatment of VV were discussed.


Assuntos
Varizes , Insuficiência Venosa , Humanos , Varizes/etiologia , Varizes/patologia , Veias/patologia , Insuficiência Venosa/patologia , Extremidade Inferior/patologia , Doença Crônica , Inflamação/patologia
7.
Khirurgiia (Mosk) ; (2): 52-58, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38344960

RESUMO

OBJECTIVE: To analyze the comprehensive program for prevention of thromboembolic complications in orthopedic patients. MATERIAL AND METHODS: We have analyzed thromboembolic complications in orthopedic patients after surgeries on large joints over the past 5 years (2018-2022). CONCLUSION: A comprehensive approach to prevention and treatment of thromboembolic complications including ultrasound, early surgical prevention of pulmonary embolism can significantly improve postoperative outcomes after joint replacement surgery. Vacuum aspiration retrograde thrombectomy is effective, feasible and safe for acute ilio-femoral venous thrombosis reducing hospital-stay (p=0.0124) and restoring vein patency. Widespread thromboembolic complications, especially for pulmonary embolism in 2022, are likely due to a new coronavirus infection and require careful screening of patients with risk factors with appropriate preventive antithrombotic therapy.


Assuntos
Embolia Pulmonar , Trombose Venosa , Humanos , Trombose Venosa/diagnóstico , Trombose Venosa/etiologia , Trombose Venosa/prevenção & controle , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiologia , Embolia Pulmonar/prevenção & controle , Veias , Trombectomia/efeitos adversos , Fatores de Risco , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle
8.
Khirurgiia (Mosk) ; (2): 45-51, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38344959

RESUMO

OBJECTIVE: To improve the results of treatment of deep vein thrombosis of the upper extremities sing endovascular technologies. MATERIAL AND METHODS: We analyzed safety and effectiveness of treatment in 24 patients with deep vein thrombosis of the upper extremities. All ones were divided into 2 homogeneous groups by 12 people each. In the first group, conventional anticoagulation was performed. In the second group, we used additional regional catheter thrombolysis with alteplase and, if necessary, venous stenting or balloon angioplasty for residual stenosis. Patients received apixaban at baseline and throughout 6 postoperative months. After 12 months, we performed ultrasound and clinical examination to identify deep vein patency and venous outflow disorders. Vein recanalization was evaluated as follows: <50% - minimal, 50-99% - partial, 100% - complete. The quality of life of patients was studied using the SF-36 questionnaire. RESULTS: In the first group, we observed complete vein recanalization in 25% of cases, partial - in 33%, minimal - in 41% of cases; in the second group - 83.3% and 16.7% of patients, respectively. In the first group, clinical manifestations of venous outflow disorders were absent in 25% of patients, mild disorders - 25%, moderate - 8.3%, severe - 41.7% of patients. In the second group, venous outflow was not impaired in 83.7% of patients, mild violations occurred in 16.7% of patients. In the first group, physical health was equal to 44.2±1.7 scores, psychological health - 49.3±2.3 scores; in the second group - 69.3±5.7 and 71.3±5.4 scores, respectively. CONCLUSION: Endovascular treatment improved postoperative outcomes.


Assuntos
Trombose Venosa , Humanos , Trombose Venosa/diagnóstico , Trombose Venosa/etiologia , Trombose Venosa/terapia , Qualidade de Vida , Veias , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/métodos , Stents , Extremidade Superior , Resultado do Tratamento , Estudos Retrospectivos
10.
Cancer Imaging ; 24(1): 7, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191513

RESUMO

BACKGROUND: Ultrasound (US) has been widely used in screening and differential diagnosis of gallbladder wall thickening (GWT). However, the sensitivity and specificity for diagnosing wall-thickening type gallbladder cancer are limited, leading to delayed treatment or overtreatment. We aim to explore the value of high frame rate contrast enhanced ultrasound (H-CEUS) in distinguishing wall-thickening type gallbladder cancer (malignant) from GWT mimicking malignancy (benign). METHODS: This retrospective study enrolled consecutive patients with non-acute GWT who underwent US and H-CEUS examination before cholecystectomy. Clinical information, US image and H-CEUS image characteristics between malignant and benign GWT were compared. The independent risk factors for malignant GWT on H-CEUS images were selected by multivariate logistic regression analysis. The diagnostic performance of H-CEUS in determining malignant GWT was compared with that of the gallbladder reporting and data system (GB-RADS) score. RESULTS: Forty-six patients included 30 benign GWTs and 16 malignant GWTs. Only mural layering and interface with liver on US images were significantly different between malignant and benign GWT (P < 0.05). Differences in enhancement direction, vascular morphology, serous layer continuity, wash-out time and mural layering in the venous phase of GWT on H-CEUS images were significant between malignant and benign GWT (P < 0.05). The sensitivity, specificity and accuracy of H-CEUS based on enhancement direction, vascular morphology and wash-out time in the diagnosis of malignant GWT were 93.75%, 90.00%, and 91.30%, respectively. However, the sensitivity, specificity and accuracy of the GB-RADS score were only 68.75%, 73.33% and 71.74%, respectively. The area under ROC curve (AUC) of H-CEUS was significantly higher than that of the GB-RADS score (AUC = 0.965 vs. 0.756). CONCLUSIONS: H-CEUS can accurately detect enhancement direction, vascular morphology and wash-out time of GWT, with a higher diagnostic performance than the GB-RADS score in determining wall-thickening type gallbladder cancer. This study provides a novel imaging means with high accuracy for the diagnosis of wall-thickening type gallbladder cancer, thus may be better avoiding delayed treatment or overtreatment.


Assuntos
Neoplasias da Vesícula Biliar , Humanos , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Estudos Retrospectivos , Ultrassonografia , Veias
11.
Sci Rep ; 14(1): 1327, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225286

RESUMO

Peripheral vascular diseases (PVDs) represent a significant burden on global human health and healthcare systems. With continued growth in obesity and diabetes, it is likely that the incidence of these conditions will increase. As many PVDs remain undiagnosed, low-cost and easy to use diagnostic methods are required. This work uses newly developed wearable electro-resistive morphic sensors to assess venous and arterial competence in the lower limbs of 36 healthy subjects. Comparison of this HeMo device was made to currently available benchtop light reflection rheography and photoplethymography devices. Results indicate that HeMo can detect the physiological signals of interest for both chronic venous insufficiency and peripheral arterial disease and all subjects were interpreted as healthy by each system. However, measurement repeatability of HeMo was highlighted as an issue that requires further system development. Furthermore, as HeMo captures changes in a section of limb circumference due to changes in underlying blood movement, rather than at a single point, the recorded signal is typically damped by comparison. This factor should be considered in any future developments.


Assuntos
Doença Arterial Periférica , Insuficiência Venosa , Dispositivos Eletrônicos Vestíveis , Humanos , Insuficiência Venosa/diagnóstico , Veias , Extremidade Inferior , Doença Arterial Periférica/diagnóstico
12.
J Transl Med ; 22(1): 70, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233934

RESUMO

BACKGROUND: An observational study involving patients recovered from COVID-19 was conducted in order to evaluate the presence/absence of vein wall thickness increasing, according to the severity of pulmonary involvement quantified with a CT-scoring system. METHODS: The venous wall thickness (VWT) of 31 patients (23 males and 8 females) with COVID 19 previously admitted to Federico II University Hospital of Naples was evaluated through ultrasound measurement of the common femoral Vein 1 cm proximal to the saphenous-femoral junction and the popliteal Vein 1 cm distal to the confluence of gemellary veins. Measurements were taken with an automated tool to avoid human error. All patients were evaluated in the supine position. Patients were then stratified into two groups, VWT > 1 mm and VWT < 1 mm. Lung damage was assessed through thoracic High Resolution Computer Tomography and subsequently quantified using the scoring system set out by Chung et al. CEAP-C class was calculated for all patients. RESULTS: The mean value of COVID score in VWT > 1 mm group was 7.4 (S.D. 4.83), whilst the mean value of the COVID score in the VWT < 1 mm group was 3.82 (S.D 3.34). These findings were determined to be statistically significant in a two-tie Student-T test. The linear regression test between VWT and Covid score values demonstrated a direct relationship between the two variables. CONCLUSION: These results demonstrate a link between two different aspects of the pathological effects on the vessels during a SARS-COV 2 infection. As such a common primum movens can be hypothesized in both micro-thrombotic and inflammatory processes relating to COVID 19.


Assuntos
COVID-19 , Masculino , Feminino , Humanos , Veias , Ultrassonografia , Pulmão/diagnóstico por imagem
13.
PLoS One ; 19(1): e0296264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38206912

RESUMO

The venous system has been historically understudied despite its critical roles in blood distribution, heart function, and systemic immunity. This study dissects the microanatomy of upper arm veins at the single cell level, and how it relates to wall structure, remodeling processes, and inflammatory responses to injury. We applied single-cell RNA sequencing to 4 non-diseased human veins (3 basilic, 1 cephalic) obtained from organ donors, followed by bioinformatic and histological analyses. Unsupervised clustering of 20,006 cells revealed a complex ecosystem of endothelial cell (EC) types, smooth muscle cell (SMCs) and pericytes, various types of fibroblasts, and immune cell populations. The venous endothelium showed significant upregulation of cell adhesion genes, with arteriovenous zonation EC phenotypes highlighting the heterogeneity of vasa vasorum (VV) microvessels. Venous SMCs had atypical contractile phenotypes and showed widespread localization in the intima and media. MYH11+DESlo SMCs were transcriptionally associated with negative regulation of contraction and pro-inflammatory gene expression. MYH11+DEShi SMCs showed significant upregulation of extracellular matrix genes and pro-migratory mediators. Venous fibroblasts ranging from secretory to myofibroblastic phenotypes were 4X more abundant than SMCs and widely distributed throughout the wall. Fibroblast-derived angiopoietin-like factors were identified as versatile signaling hubs to regulate angiogenesis and SMC proliferation. An abundant monocyte/macrophage population was detected and confirmed by histology, including pro-inflammatory and homeostatic phenotypes, with cell counts positively correlated with age. Ligand-receptor interactome networks identified the venous endothelium in the main lumen and the VV as a niche for monocyte recruitment and infiltration. This study underscores the transcriptional uniqueness of venous cells and their relevance for vascular inflammation and remodeling processes. Findings from this study may be relevant for molecular investigations of upper arm veins used for vascular access creation, where single-cell analyses of cell composition and phenotypes are currently lacking.


Assuntos
Ecossistema , Veias , Humanos , Fenótipo , Células Cultivadas , Perfilação da Expressão Gênica , Miócitos de Músculo Liso/metabolismo
14.
Clin Radiol ; 79(3): e393-e400, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38182477

RESUMO

AIM: To compare the performance of two non-contrast magnetic resonance angiography (MRA) sequences, silent MRA and time of flight (TOF) MRA, in the evaluation of intracranial dural arteriovenous fistula (DAVF). MATERIALS AND METHODS: Forty consecutive patients with DAVF were enrolled and evaluated prospectively using silent MRA, TOF MRA, and digital subtraction angiography (DSA). The location, Cognard classification, arterial feeders, and venous drainage were evaluated. The therapeutic strategy and possible route were predicted on both silent and TOF MRA and these were compared with DSA during subsequent endovascular treatment. RESULTS: Sensitivity and accuracy of silent and TOF MRA for localisation (96.4% versus 96% and 96% versus 95%, respectively) and classification (96% versus 94% and 96% versus 93.5%, respectively) were high. Silent MRA showed higher sensitivity than TOF MRA for arterial feeders and draining veins (87% versus 79% and 81.6% versus 67%). This improved to a sensitivity of 96.4% and 89% when prominent feeders were considered. The sensitivity and accuracy were 92.6% and 85.8% for immediate draining veins. Both silent and TOF MRA were accurate for therapeutic planning (96% versus 85%), although silent MRA was more accurate. CONCLUSION: Silent MRA can more reliably evaluate the various angioarchtectural components of DAVF compared to TOF MRA.


Assuntos
Malformações Vasculares do Sistema Nervoso Central , Angiografia por Ressonância Magnética , Humanos , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Angiografia Digital , Veias , Espectroscopia de Ressonância Magnética
15.
Khirurgiia (Mosk) ; (1): 119-126, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38258698

RESUMO

Despite notable progress in the prevention of venous thromboembolic complications (VTE) and its widespread use in recent decades, mortality in cancer patients from VTE is still second only to the main disease. Some features and limitations in cancer patients, such as a decrease in kidney function and platelet count, an increased risk of bleeding, and the difficulty of monitoring the adequacy and safety of thromboprophylaxis, as well as the use of aggressive chemotherapy, determine the need for more effective and safer ways to solve the problem of VTE. Also, in the case of surgical interventions in such patients, the need for preoperative thromboprophylaxis raises new challenges for doctors. The article presents a review of the issue using a clinical case.


Assuntos
Neoplasias , Insuficiência Renal , Tromboembolia Venosa , Humanos , Anticoagulantes/efeitos adversos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Veias , Rim , Neoplasias/complicações , Neoplasias/cirurgia
16.
Neuroimage ; 286: 120517, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38211705

RESUMO

Recently, Clarke et al. published a study using spinal cord susceptibility weighted imaging in multiple sclerosis patients at 7T. They discovered dilated intradural extramedullary veins surrounding the cord. The purpose of this commentary is to point out some recent research by our group, which suggests this dilatation also occurs in the bridging cortical veins surrounding the brain. The dilatation indicates a focal elevation in the venous pressure secondary to impedance mismatching. Due to the shared outflow geometry, dilatation of the outflow veins will obstruct the glymphatic pathway of the spinal cord altering the immune response.


Assuntos
Sistema Glinfático , Esclerose Múltipla , Humanos , Veias , Encéfalo/irrigação sanguínea , Medula Espinal , Imageamento por Ressonância Magnética/métodos
17.
J Biomed Opt ; 29(1): 016009, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38283936

RESUMO

Significance: Laser speckle contrast imaging (LSCI) is a real-time wide-field technique that is applied to visualize blood flow in biomedical applications. However, there is currently a lack of relevant research to demonstrate that it can measure velocities over a wide dynamic range (WDR), which is critical for monitoring much higher and more pulsatile blood flow in larger size myocardial vessels, such as the coronary artery bypass graft, and visualizing the spatio-temporal evolution of myocardial blood flow perfusion in cardiac surgery. Aim: We aim to demonstrate that the LSCI technique enables measuring velocities over a WDR from phantom experiments to animal experiments. In addition, LSCI is preliminarily applied to imaging myocardial blood flow distribution in vivo on rabbits. Approach: Phantom and animal experiments are performed to verify that the LSCI method has the ability to measure blood velocities over a wide range. Our method is also validated by transit time flow measurement, which is the gold standard for blood flow measurement in cardiac surgery. Results: Our method is demonstrated to measure the blood flow over a wide range from 0.2 to 635 mm/s. To validate the phantom results, the varying blood flow rate from 0 to 320 mm/s is detected in the rat carotid artery. Additionally, our technique also obtains blood flow maps of different myocardial vessels, such as superficial large/small veins, veins surrounded by fat, and myocardial deeper arteriole. Conclusions: Our study has the potential to visualize the spatio-temporal evolution of myocardial perfusion in coronary artery bypass grafting, which would be of great benefit for future research in the life sciences and clinical medicine.


Assuntos
Hemodinâmica , Imagem de Contraste de Manchas a Laser , Ratos , Animais , Coelhos , Velocidade do Fluxo Sanguíneo , Fluxo Sanguíneo Regional/fisiologia , Veias , Fluxometria por Laser-Doppler/métodos
18.
Comput Methods Programs Biomed ; 244: 107997, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176329

RESUMO

BACKGROUND AND OBJECTIVE: Liver cancer seriously threatens human health. In clinical diagnosis, contrast-enhanced computed tomography (CECT) images provide important supplementary information for accurate liver tumor segmentation. However, most of the existing methods of liver tumor automatic segmentation focus only on single-phase image features. And the existing multi-modal methods have limited segmentation effect due to the redundancy of fusion features. In addition, the spatial misalignment of multi-phase images causes feature interference. METHODS: In this paper, we propose a phase attention network (PA-Net) to adequately aggregate multi-phase information of CT images and improve segmentation performance for liver tumors. Specifically, we design a PA module to generate attention weight maps voxel by voxel to efficiently fuse multi-phase CT images features to avoid feature redundancy. In order to solve the problem of feature interference in the multi-phase image segmentation task, we design a new learning strategy and prove its effectiveness experimentally. RESULTS: We conduct comparative experiments on the in-house clinical dataset and achieve the SOTA segmentation performance on multi-phase methods. In addition, our method has improved the mean dice score by 3.3% compared with the single-phase method based on nnUNet, and our learning strategy has improved the mean dice score by 1.51% compared with the ML strategy. CONCLUSION: The experimental results show that our method is superior to the existing multi-phase liver tumor segmentation method, and provides a scheme for dealing with missing modalities in multi-modal tasks. In addition, our proposed learning strategy makes more effective use of arterial phase image information and is proven to be the most effective in liver tumor segmentation tasks using thick-layer CT images. The source code is released on (https://github.com/Houjunfeng203934/PA-Net).


Assuntos
Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Veias , Artérias , Tomografia Computadorizada por Raios X , Processamento de Imagem Assistida por Computador
19.
BMJ Case Rep ; 17(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191222

RESUMO

We report a case of the formation of a dural arteriovenous fistula (dAVF) of the transverse-sigmoid sinus following venous sinus stenting (VSS), treated with trans-arterial embolisation and venous remodelling. An obese woman in her 30s presented with persistent daily headaches after undergoing endoscopic repair of a skull base cerebrospinal fluid leak. Angiography demonstrated a focal right transverse-sigmoid sinus stenosis, and she underwent VSS of the right transverse sinus. She developed progressive pulsatile tinnitus within 3 months, and angiography demonstrated the formation of a Borden type 1 dAVF along the stent. Trans-arterial embolisation of the dAVF was performed with venous remodelling using a Copernic RC balloon. While VSS has become a promising treatment for venous sinus stenosis and idiopathic intracranial hypertension, dAVF formation is a rare but significant potential complication. Embolisation with venous remodelling can be performed to treat these lesions.


Assuntos
Malformações Vasculares do Sistema Nervoso Central , Besouros , Embolização Terapêutica , Feminino , Animais , Humanos , Constrição Patológica , Veias , Aeronaves , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/cirurgia , Cefaleia
20.
Br J Nurs ; 33(2): S20-S26, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38271043

RESUMO

Central venous access devices (CVADs), including peripherally inserted central catheters (PICCs) and cuffed tunnelled catheters, play a crucial role in modern medicine by providing reliable access for medication and treatments directly into the bloodstream. However, these vital medical devices also pose a significant risk of catheter-related bloodstream infections (CRBSIs) alongside associated complications such as thrombosis or catheter occlusion. To mitigate these risks, healthcare providers employ various strategies, including the use of locking solutions in combination with meticulous care and maintenance protocols. KiteLock 4% catheter lock is a solution designed to combat the triple threat of infection, occlusion and biofilm. This locking solution is described as the only locking solution to provide cover for all three complications.


Assuntos
Infecções Relacionadas a Cateter , Cateterismo Venoso Central , Cateterismo Periférico , Cateteres Venosos Centrais , Trombose , Humanos , Veias , Infecções Relacionadas a Cateter/prevenção & controle
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