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1.
Eur J Oncol Nurs ; 67: 102445, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37871414

RESUMO

PURPOSE: Implantable venous access ports are widely used in patients receiving chemotherapy, but there is still scarce evidence about any patient-reported outcome measures. This prospective randomized controlled trial examined the impact on patients' quality-of-life following the placement of an implantable port device for long-term chemotherapy treatment. METHOD: A total of 120 chemotherapy naïve adult outpatients scheduled to receive chemotherapy (duration ≥12 weeks) for solid tissue tumors in a single academic oncology unit were randomly allocated (n = 60 in each arm) between radiologically guided insertion of an implantable venous access port (PORT arm) or standard repeated peripheral venous access (Control arm). Health-related quality-of-life scores (HRQoL) were assessed with the EQ-5D-5L and the oncology-specific EORTC QLQ-C30 (version 3.0) questionnaires at baseline, 3- and 6-months post randomization. Non-parametric tests were applied and differences between medians (Δ) are reported because of skewed-left HRQoL data. RESULTS: Baseline clinical and demographic characteristics were well balanced between the two groups. There were no complications during insertion and no infection or device failure in the PORT subjects through the 6-month follow-up. The functional and symptom scales of the EORTC QLQ-C30 questionnaire were similar between both study arms at all time intervals. The EORTC QLQ-C30 global health status was significantly improved in the PORT subjects both at 3 months (Δ: 8.3 out of 100; P = 0.04) and 6 months follow-up (Δ: 16.7 out of 100; P = 0.003). Changes in EQ-5D-5L scores were significantly improved at 6 months in the PORT arm compared to control (Δ: 0.074 out of 1; P = 0.01). CONCLUSIONS: Implantable venous access ports may confer significantly improved patient-reported quality-of-life benefits in patients receiving chemotherapy for solid tissue tumors.


Assuntos
Cateterismo Venoso Central , Cateteres Venosos Centrais , Neoplasias , Adulto , Humanos , Cateterismo Venoso Central/efeitos adversos , Qualidade de Vida , Estudos Prospectivos , Neoplasias/tratamento farmacológico
2.
Vascular ; 31(5): 1011-1016, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35549952

RESUMO

PURPOSE: This study aims to investigate the safety and efficacy of a new device using microwave technology for the endovenous ablation of the great saphenous vein (GSV) causing symptomatic lower limb varicose veins (LLVV). MATERIALS AND METHODS: This prospective, single-arm, single-center, cohort study investigated the safety and effectiveness of endovenous microwave ablation for the treatment of symptomatic LLVV. Enrollment period was set between January and December 2020. Primary safety endpoint was the occurrence of procedure-related complications and primary efficacy endpoint was anatomical success defined as the duplex ultrasound (DUS)-proven GSV occlusion at 1 year follow-up. Secondary endpoints included 1-year clinical success (CEAP classification improvement), repeat procedures rate due to GSV recanalization, and pain assessment at 24 h post treatment. RESULTS: In total, 50 patients (42 female; mean age: 62 ± 12 years) with 64 limbs were treated. No procedure-related complications were noted. Technical success was 95.3% (61/64 GSVs), as three cases of GSV recanalization were detected. Clinical success was 100%, as in all cases symptoms improvement by at least one grade according to CEAP classification, was achieved. Mean CEAP grade significantly improved from 3.3 ± 0.72 (median: 3) at baseline to 1.8 ± 0.85 (median: 2) at 1-year (p < 0.0001). There were no repeat procedures due to GSC recanalization. The median 24-h VAS value was 2 (mean: 1.9 ± 1.4). CONCLUSIONS: Endovenous microwave ablation was safe and effective for the treatment of varicose veins, achieving high 1-year GSV occlusion rates.


Assuntos
Terapia a Laser , Varizes , Insuficiência Venosa , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Estudos de Coortes , Estudos Prospectivos , Micro-Ondas/efeitos adversos , Resultado do Tratamento , Varizes/diagnóstico por imagem , Varizes/cirurgia , Extremidade Inferior , Veia Safena/diagnóstico por imagem , Veia Safena/cirurgia , Terapia a Laser/efeitos adversos , Insuficiência Venosa/diagnóstico por imagem , Insuficiência Venosa/cirurgia , Insuficiência Venosa/etiologia
3.
Phys Med Biol ; 65(21): 215027, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32998480

RESUMO

Chronic liver disease (CLD) is currently one of the major causes of death worldwide. If not treated, it may lead to cirrhosis, hepatic carcinoma and death. Ultrasound (US) shear wave elastography (SWE) is a relatively new, popular, non-invasive technique among radiologists. Although many studies have been published validating the SWE technique either in a clinical setting, or by applying machine learning on SWE elastograms, minimal work has been done on comparing the performance of popular pre-trained deep learning networks on CLD assessment. Currently available literature reports suggest technical advancements on specific deep learning structures, with specific inputs and usually on a limited CLD fibrosis stage class group, with limited comparison on competitive deep learning schemes fed with different input types. The aim of the present study is to compare some popular deep learning pre-trained networks using temporally stable and full elastograms, with or without augmentation as well as propose suitable deep learning schemes for CLD diagnosis and progress assessment. 200 liver biopsy validated patients with CLD, underwent US SWE examination. Four images from the same liver area were saved to extract elastograms and processed to exclude areas that were temporally unstable. Then, full and temporally stable masked elastograms for each patient were separately fed into GoogLeNet, AlexNet, VGG16, ResNet50 and DenseNet201 with and without augmentation. The networks were tested for differentiation of CLD stages in seven classification schemes over 30 repetitions using liver biopsy as the reference. All networks achieved maximum mean accuracies ranging from 87.2%-97.4% and area under the receiver operating characteristic curves (AUCs) ranging from 0.979-0.990 while the radiologists had AUCs ranging from 0.800-0.870. ResNet50 and DenseNet201 had better average performance than the other networks. The use of the temporal stability mask led to improved performance on about 50% of inputs and network combinations while augmentation led to lower performance for all networks. These findings can provide potential networks with higher accuracy and better setting in the CLD diagnosis and progress assessment. A larger data set would help identify the best network and settings for CLD assessment in clinical practice.


Assuntos
Aprendizado Profundo , Técnicas de Imagem por Elasticidade , Processamento de Imagem Assistida por Computador/métodos , Hepatopatias/diagnóstico por imagem , Biópsia , Doença Crônica , Feminino , Humanos , Hepatopatias/patologia , Masculino , Pessoa de Meia-Idade , Curva ROC
4.
Eur Radiol Exp ; 4(1): 47, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32875390

RESUMO

BACKGROUND: Foot perfusion has been recently implemented as a new tool for optimizing outcomes of peripheral endovascular procedures. A custom-made, two-dimensional perfusion digital subtraction angiography (PDSA) algorithm has been implemented to quantify outcomes of endovascular treatment of critical limb ischemia (CLI), assist intra-procedural decision-making, and enhance clinical outcomes. METHODS: The study was approved by the Hospital's Ethics Committee. This prospective, single-center study included seven consecutive patients scheduled to undergo infrapopliteal endovascular treatment of CLI. Perfusion blood volume (PBV), mean transit time (MTT), and perfusion blood flow (PBF) maps were extracted by analyzing time-intensity curves and signal intensity on the perfused vessel mask. Mean values calculated from user-specified regions of interest (ROIs) on perfusion maps were employed to evaluate pre- and post-endovascular treatment condition. Measurements were performed immediately after final PDSA. RESULTS: In total, five patients (aged 54 ± 16 years, mean ± standard deviation) were analyzed, as two patients were excluded due to significant motion artifacts. Post-procedural MTT presented a mean decrease of 19.1% for all patients and increased only in 1 of 5 patients, demonstrating in 4/5 patients an increase in tissue perfusion after revascularization. Overall mean PBF and PBV values were also analogously increased following revascularization (446% and 69.5% mean, respectively) and in the majority of selected ROIs (13/15 and 12/15 ROIs, respectively). CONCLUSIONS: Quantification of infrapopliteal angioplasty outcomes using this newly proposed, custom-made, intra-procedural PDSA algorithm was performed using PBV, MTT, and PBF maps. Further studies are required to determine its role in peripheral endovascular procedures ( ClinicalTrials.gov Identifier: NCT04356092).


Assuntos
Angiografia Digital , Procedimentos Endovasculares/métodos , Pé/irrigação sanguínea , Isquemia/diagnóstico por imagem , Isquemia/cirurgia , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/cirurgia , Software , Algoritmos , Velocidade do Fluxo Sanguíneo , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Interpretação de Imagem Radiográfica Assistida por Computador
5.
Med Phys ; 46(5): 2298-2309, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30929260

RESUMO

PURPOSE: To automatically detect and isolate areas of low and high stiffness temporal stability in shear wave elastography (SWE) image sequences and define their impact in chronic liver disease (CLD) diagnosis improvement by means of clinical examination study and deep learning algorithm employing convolutional neural networks (CNNs). MATERIALS AND METHODS: Two hundred SWE image sequences from 88 healthy individuals (F0 fibrosis stage) and 112 CLD patients (46 with mild fibrosis (F1), 16 with significant fibrosis (F2), 22 with severe fibrosis (F3), and 28 with cirrhosis (F4)) were analyzed to detect temporal stiffness stability between frames. An inverse Red, Green, Blue (RGB) colormap-to-stiffness process was performed for each image sequence, followed by a wavelet transform and fuzzy c-means clustering algorithm. This resulted in a binary mask depicting areas of high and low stiffness temporal stability. The mask was then applied to the first image of the SWE sequence, and the derived, masked SWE image was used to estimate its impact in standard clinical examination and CNN classification. Regarding the impact of the masked SWE image in clinical examination, one measurement by two radiologists was performed in each SWE image and two in the corresponding masked image measuring areas with high and low stiffness temporal stability. Then, stiffness stability parameters, interobserver variability evaluation and diagnostic performance by means of ROC analysis were assessed. The masked and unmasked sets of SWE images were fed into a CNN scheme for comparison. RESULTS: The clinical impact evaluation study showed that the masked SWE images decreased the interobserver variability of the radiologists' measurements in the high stiffness temporal stability areas (interclass correlation coefficient (ICC) = 0.92) compared to the corresponding unmasked ones (ICC = 0.76). In terms of diagnostic accuracy, measurements in the high-stability areas of the masked SWE images (area-under-the-curve (AUC) ranging from 0.800 to 0.851) performed similarly to those in the unmasked SWE images (AUC ranging from 0.805 to 0.893). Regarding the measurements in the low stiffness temporal stability areas of the masked SWE images, results for interobserver variability (ICC = 0.63) and diagnostic accuracy (AUC ranging from 0.622 to 0.791) were poor. Regarding the CNN classification, the masked SWE images showed improved accuracy (ranging from 82.5% to 95.5%) compared to the unmasked ones (ranging from 79.5% to 93.2%) for various CLD stage combinations. CONCLUSION: Our detection algorithm excludes unreliable areas in SWE images, reduces interobserver variability, and augments CNN's accuracy scores for many combinations of fibrosis stages.


Assuntos
Aprendizado Profundo , Técnicas de Imagem por Elasticidade , Processamento de Imagem Assistida por Computador/métodos , Cirrose Hepática/diagnóstico por imagem , Fígado/diagnóstico por imagem , Fígado/patologia , Estudos de Casos e Controles , Doença Crônica , Fibrose , Humanos , Reprodutibilidade dos Testes , Fatores de Tempo
6.
Expert Rev Med Devices ; 15(4): 283-291, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29546804

RESUMO

INTRODUCTION: Thrombosis is the most important access-related complication. Several declotting procedures have been suggested falling mainly into two categories; thrombolysis-dependent and thrombectomy-dependent. AREAS COVERED: Seventeen studies after 2001 have been published on percutaneous treatment of thrombosed vascular access. Authors performed a systematic review of these studies together with a parametric meta-analysis of data available investigating clinical success, postintervention assisted primary patency (PAPP) and independent factors that could influence outcome measures. EXPERT COMMENTARY: A shift to thrombectomy-dependent procedures is observed with a view to diminishing complications from the use of thrombolytic agents. Arteriovenous fistulas provide significantly better PAPP, while newer studies show improved, non-significant results compared with older ones. The role of improvement of devices for subsequent angioplasty is of equal importance, if not more, for improved declotting results.


Assuntos
Trombólise Mecânica , Diálise Renal/efeitos adversos , Trombose/terapia , Dispositivos de Acesso Vascular , Feminino , Humanos , Masculino , Trombólise Mecânica/instrumentação , Trombólise Mecânica/métodos , Diálise Renal/instrumentação , Diálise Renal/métodos , Trombose/etiologia
7.
Cardiovasc Intervent Radiol ; 41(2): 245-252, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29075875

RESUMO

BACKGROUND: This is a retrospective single-center analysis investigating the results of a percutaneous lysis-assisted balloon (LAB) thrombectomy procedure for the treatment of thrombosed arteriovenous dialysis grafts (AVGs). MATERIALS AND METHODS: Within 5 years (January 2012-December 2016), 291 declotting procedures were performed for the treatment of thrombosed dialysis arteriovenous fistulas or grafts. Data were available for 129 patients (75 men, 58.1%) with an AVG, undergoing 241 procedures [1.87 procedures/patient (1-10)]. Procedure includes initial lysis with 5 mg recombinant tissue plasminogen activator followed by thrombectomy with a high-pressure balloon for thrombus maceration using "facing sheaths" technique. 61 patients had ≥ 2 declotting procedures. In 80 cases (80/241; 33.2%), a stent graft (SG) was used for treatment of persistent stenosis. Main primary outcome measures were clinical success and postintervention assisted primary patency (PAPP). Secondary outcome measures included procedural complications and investigation of independent factors that could influence circuit survival. RESULTS: Median PAPP was 434 days according to Kaplan-Meier survival analysis. Clinical success was 96.26%. In six cases (6/241, 2.49%) declotting failed and a catheter was placed. There were 16 minor (16/241, 6.64%) and no major complications. There was no significant difference in circuit survival regardless of SG use (No SG 406 days vs. SG 349 days; p = 0.24). There was a significant difference in favor of the second declotting compared to the first in 61 patients (first: 162 days vs. second: 447 days; p < 0.0001). CONCLUSION: LAB thrombectomy resulted in high-circuit survival rates with increased technical success and minimum complications without the use of thrombectomy devices.


Assuntos
Angioplastia com Balão , Derivação Arteriovenosa Cirúrgica , Prótese Vascular , Complicações Pós-Operatórias/terapia , Diálise Renal , Trombectomia/métodos , Trombose/terapia , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Stents , Ativador de Plasminogênio Tecidual/uso terapêutico
8.
PLoS One ; 12(9): e0184597, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28934265

RESUMO

BACKGROUND: The optimal transcatheter embolization strategy for patients with unresectable hepatocellular carcinoma (HCC) remains elusive. We conducted a systematic review and network meta-analysis (NMA) of different embolization options for unresectable HCC. METHODS: Medical databases were searched for randomized controlled trials evaluating bland transarterial embolization (TAE), conventional TACE, drug-eluting bead chemoembolization (DEB-TACE), or transarterial radioembolization (TARE), either alone or combined with adjuvant chemotherapy, or local liver ablation, or external radiotherapy for unresectable HCC up to June 2017. Random effects Bayesian models with a binomial and normal likelihood were fitted (WinBUGS). Primary endpoint was patient survival expressed as hazard ratios (HR) and 95% credible intervals. An exponential model was used to fit patient survival curves. Safety and objective response were calculated as odds ratios (OR) and accompanying 95% credible intervals. Competing treatments were ranked with the SUCRA statistic. Heterogeneity-adjusted effective sample sizes were calculated to evaluate information size for each comparison. Quality of evidence (QoE) was assessed with the GRADE system adapted for NMA reports. All analyses complied with the ISPOR-AMCP-NCP Task Force Report for good practice in NMA. FINDINGS: The network of evidence included 55 RCTs (12 direct comparisons) with 5,763 patients with preserved liver function and unresectable HCC (intermediate to advanced stage). All embolization strategies achieved a significant survival gain over control treatment (HR range, 0.42-0.76; very low-to-moderate QoE). However, TACE, DEB-TACE, TARE and adjuvant systemic agents did not confer any survival benefit over bland TAE alone (moderate QoE, except low in case of TARE). There was moderate QoE that TACE combined with external radiation or liver ablation achieved the best patient survival (SUCRA 86% and 96%, respectively). Estimated median survival was 13.9 months in control, 18.1 months in TACE, 20.6 months with DEB-TACE, 20.8 months with bland TAE, 30.1 months in TACE plus external radiotherapy, and 33.3 months in TACE plus liver ablation. TARE was the safest treatment (SUCRA 77%), however, all examined therapies were associated with a significantly higher risk of toxicity over control (OR range, 6.35 to 68.5). TACE, DEB-TACE, TARE and adjuvant systemic agents did not improve objective response over bland embolization alone (OR range, 0.85 to 1.65). There was clinical diversity among included randomized controlled trials, but statistical heterogeneity was low. CONCLUSIONS: Chemo- and radio-embolization for unresectable hepatocellular carcinoma may improve tumour objective response and patient survival, but are not more effective than bland particle embolization. Chemoembolization combined with external radiotherapy or local liver ablation may significantly improve tumour response and patient survival rates over embolization monotherapies. Quality of evidence remains mostly low to moderate because of clinical diversity. SYSTEMATIC REVIEW REGISTRATION: CRD42016035796 (http://www.crd.york.ac.uk/PROSPERO).


Assuntos
Carcinoma Hepatocelular/terapia , Embolização Terapêutica , Pesquisa Comparativa da Efetividade , Embolização Terapêutica/métodos , Humanos , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Curr Vasc Pharmacol ; 15(5): 430-445, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28595535

RESUMO

BACKGROUND: Pharmacotherapy is of increasing interest in peripheral arterial disease (PAD), with novel therapies aiming at different factors contributing to the disease. For antiplatelet therapy, there is no unanimous agreement regarding the nature or duration of optimal antiplatelet therapy so as to reduce major adverse cardiovascular and limb-related events (e.g. repeat interventions and amputations). However, evidence on novel more potent antithrombotic agents, drug combinations and personalized antiplatelet therapy for PAD patients is accumulating. Similarly, statins are now considered as a standard of care in PAD patients, due to their multiple actions which include plaque stabilization, antiinflammatory properties and regression of atheroma. CONCLUSION: This review focuses on current evidence available for various antiplatelet regimens and statin therapy for PAD and discusses future perspectives. We consider randomized controlled trials, together with the most important reviews and meta-analyses. Treatment algorithms based on currently available data.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Doença Arterial Periférica/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Desenho de Fármacos , Quimioterapia Combinada , Fibrinolíticos/administração & dosagem , Fibrinolíticos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Medicina de Precisão , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo
10.
Ultrasound Med Biol ; 43(9): 1797-1810, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28634041

RESUMO

The purpose of the present study was to employ a computer-aided diagnosis system that classifies chronic liver disease (CLD) using ultrasound shear wave elastography (SWE) imaging, with a stiffness value-clustering and machine-learning algorithm. A clinical data set of 126 patients (56 healthy controls, 70 with CLD) was analyzed. First, an RGB-to-stiffness inverse mapping technique was employed. A five-cluster segmentation was then performed associating corresponding different-color regions with certain stiffness value ranges acquired from the SWE manufacturer-provided color bar. Subsequently, 35 features (7 for each cluster), indicative of physical characteristics existing within the SWE image, were extracted. A stepwise regression analysis toward feature reduction was used to derive a reduced feature subset that was fed into the support vector machine classification algorithm to classify CLD from healthy cases. The highest accuracy in classification of healthy to CLD subject discrimination from the support vector machine model was 87.3% with sensitivity and specificity values of 93.5% and 81.2%, respectively. Receiver operating characteristic curve analysis gave an area under the curve value of 0.87 (confidence interval: 0.77-0.92). A machine-learning algorithm that quantifies color information in terms of stiffness values from SWE images and discriminates CLD from healthy cases is introduced. New objective parameters and criteria for CLD diagnosis employing SWE images provided by the present study can be considered an important step toward color-based interpretation, and could assist radiologists' diagnostic performance on a daily basis after being installed in a PC and employed retrospectively, immediately after the examination.


Assuntos
Diagnóstico por Computador/métodos , Técnicas de Imagem por Elasticidade/métodos , Hepatopatias/diagnóstico por imagem , Aprendizado de Máquina , Adolescente , Idoso , Algoritmos , Doença Crônica , Cor , Feminino , Humanos , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
11.
J Diabetes Complications ; 31(7): 1109-1114, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28479156

RESUMO

AIMS: Diagnosis of vascular involvement in diabetic foot ulceration (DFU) remains challenging. We conducted a proof of concept study to investigate the feasibility of microwave radiometry (MWR) thermometry for non-invasive differential diagnosis of critical limb ischemia (CLI) in subjects with DFU. METHODS: This prospective, multi-center, study included 80 participants, divided into four groups (group N: normal control subjects; group DN: participants with diabetes and verified neuropathic ulcers without vascular involvement; group DC: participants with diabetes and CLI and group NDC: participants with CLI without diabetes). Vascular disease was confirmed with angiography. All patients underwent MWR (RTM-01-RES:University of Bolton, UK) to record mean tissue temperatures at various pre-determined foot sites. Comparisons of temperature measurements between study groups were performed using one-way ANOVA and Dunn tests. ROC analysis was performed to determine sensitivity, specificity and cut-off value of MWR for CLI diagnosis. RESULTS: Temperatures recorded in vicinity to the foot ulcers of participants with diabetes and CLI were similar to those with CLI without diabetes, but significantly lower than in subjects with neuropathic ulcers without vascular involvement and normal controls (group DC:29.30°C±1.89 vs. group NDC:29.18°C±1.78vs. group N:33.01°C±0.45 vs. group DN:33.39°C±1.37;P<.0001). According to ROC analysis, cut-off temperature value to diagnose CLI was <31.8°C (area under the curve: 0.984; 95% CI: 0.965-1.005;P<.001), with a sensitivity of 100.0% (95%CI: 90.26-100.0) and specificity of 88.37% (95% CI: 74.92-96.11). CONCLUSIONS: Tissue temperatures in vicinity to ulcers were significantly lower in participants with CLI, with or without diabetes, compared to non-ischemic controls. MWR could be used for differential diagnosis of arterial ischemia in subjects with DFU.


Assuntos
Angiopatias Diabéticas/diagnóstico , Pé Diabético/etiologia , Isquemia/diagnóstico , Extremidade Inferior/irrigação sanguínea , Idoso , Idoso de 80 Anos ou mais , Estado Terminal , Angiopatias Diabéticas/fisiopatologia , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Pé/irrigação sanguínea , Humanos , Isquemia/etiologia , Masculino , Micro-Ondas , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Estudos Prospectivos , Radiometria , Sensibilidade e Especificidade , Termometria
12.
Med Phys ; 44(7): 3695-3705, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28432822

RESUMO

PURPOSE: To automatically segment and classify focal liver lesions (FLLs) on nonenhanced T2-weighted magnetic resonance imaging (MRI) scans using a computer-aided diagnosis (CAD) algorithm. METHODS: 71 FLLs (30 benign lesions, 19 hepatocellular carcinomas, and 22 metastases) on T2-weighted MRI scans were delineated by the proposed CAD scheme. The FLL segmentation procedure involved wavelet multiscale analysis to extract accurate edge information and mean intensity values for consecutive edges computed using horizontal and vertical analysis that were fed into the subsequent fuzzy C-means algorithm for final FLL border extraction. Texture information for each extracted lesion was derived using 42 first- and second-order textural features from grayscale value histogram, co-occurrence, and run-length matrices. Twelve morphological features were also extracted to capture any shape differentiation between classes. Feature selection was performed with stepwise multilinear regression analysis that led to a reduced feature subset. A multiclass Probabilistic Neural Network (PNN) classifier was then designed and used for lesion classification. PNN model evaluation was performed using the leave-one-out (LOO) method and receiver operating characteristic (ROC) curve analysis. RESULTS: The mean overlap between the automatically segmented FLLs and the manual segmentations performed by radiologists was 0.91 ± 0.12. The highest classification accuracies in the PNN model for the benign, hepatocellular carcinoma, and metastatic FLLs were 94.1%, 91.4%, and 94.1%, respectively, with sensitivity/specificity values of 90%/97.3%, 89.5%/92.2%, and 90.9%/95.6% respectively. The overall classification accuracy for the proposed system was 90.1%. CONCLUSIONS: Our diagnostic system using sophisticated FLL segmentation and classification algorithms is a powerful tool for routine clinical MRI-based liver evaluation and can be a supplement to contrast-enhanced MRI to prevent unnecessary invasive procedures.


Assuntos
Algoritmos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Meios de Contraste , Humanos , Curva ROC , Sensibilidade e Especificidade
13.
Cardiovasc Intervent Radiol ; 40(7): 964-977, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28451812

RESUMO

Traditional percutaneous balloon angioplasty and stent placement is based on mechanical plaque disruption and displacement within the arterial wall. On the contrary, transcatheter atherectomy achieves atherosclerotic plaque clearance by means of directional plaque excision or rotational plaque removal or laser plaque ablation. Debulking atherectomy may allow for a more uniform angioplasty result at lower pressures with consequently less vessel barotrauma and improved luminal gain, thereby decreasing the risk of plaque recoil and dissection that may require permanent metal stenting. It has been also argued that atherectomy may disrupt the calcium barrier and optimize drug transfer and delivery in case of drug-coated balloon applications. The authors discuss the various types of atherectomy devices available in clinical practice to date and critically appraise their mode of action as well as relevant published data in each case. Overall, amassed randomized and observational evidence indicates that percutaneous atherectomy of the femoropopliteal and infrapopliteal arteries may achieve high technical success rates and seems to lessen the frequency of bailout stenting, however, at the expense of increased risk of peri-procedural distal embolization. Long-term clinical outcomes reported to date do not support the superiority of percutaneous atherectomy over traditional balloon angioplasty and stent placement in terms of vessel patency or limb salvage. The combination of debulking atherectomy and drug-coated balloons has shown promise in early studies, especially in the treatment of more complex lesions. Unanswered questions and future perspectives of this continuously evolving endovascular technology as part of a broader treatment algorithm are discussed.


Assuntos
Aterectomia/instrumentação , Procedimentos Cirúrgicos de Citorredução/instrumentação , Procedimentos Endovasculares/instrumentação , Doenças Vasculares Periféricas/cirurgia , Algoritmos , Desenho de Equipamento , Artéria Femoral/cirurgia , Humanos , Salvamento de Membro/instrumentação , Ensaios Clínicos Controlados Aleatórios como Assunto , Stents , Grau de Desobstrução Vascular
14.
Expert Opin Biol Ther ; 17(4): 449-456, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28133976

RESUMO

INTRODUCTION: Critical limb ischemia (CLI) constitutes a life-limiting and life-threatening disease. Revascularization, either endovascular or surgical, remains the best treatment option accompanied by medication and risk factor modification. Patients unable to undergo revascularization, referred as 'no-option patients', have been the center of interest the last few years, subjected to treatment therapies based on proteins (mainly growth factors) involved in angiogenesis via gene delivery to the ischemic tissue. Areas covered: This review focuses on these growth factors, gives an update of the studies available, discusses the possible problems that influence outcomes and describes future perspectives including possible new technologies that will improve them. Additionally, the authors attempt to place therapeutic angiogenesis to the bigger frame of tailored therapy in CLI. Expert opinion: Although encouraging in the beginning, growth factor therapy results have been equivocal and inconclusive. And while it would be misleading to approach gene therapy as panacea, its effect on the micro-circulatory level activating angiogenesis and arteriogenesis could act as an important adjunct in personalized treatment.


Assuntos
Extremidades/irrigação sanguínea , Técnicas de Transferência de Genes , Terapia Genética/métodos , Isquemia/genética , Isquemia/terapia , Animais , Ensaios Clínicos como Assunto/métodos , Extremidades/patologia , Humanos , Isquemia/diagnóstico , Neovascularização Fisiológica/fisiologia , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/genética , Doença Arterial Periférica/terapia , Transplante de Células-Tronco/métodos , Transplante de Células-Tronco/tendências
15.
Cardiovasc Intervent Radiol ; 40(1): 50-54, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27738819

RESUMO

PURPOSE: To investigate the safety and effectiveness of lutonix paclitaxel-coated balloon (PCB) for the treatment of dysfunctional dialysis access. MATERIALS AND METHODS: This was a single-center, single-arm, retrospective analysis of 39 patients (23 male, 59 %) undergoing 61 interventions using 69 PCBs in a 20-month period. There was a balance between arteriovenous fistulae (AVF) and grafts (AVG) (20 AVFs, 19AVGs), and the majority of lesions were restenotic (25/39, 64.1 %). Mean balloon diameter used was 6.6 mm and length 73.4 mm. Primary outcome measure was target lesion primary patency (TLPP) at 6 months, while secondary outcome measures included factors affecting TLPP and major complications. As there were lesions treated more than once with PCB, authors also compared patency results after first and second PCB angioplasty. RESULTS: TLPP was 72.2 % at 6 months with a median patency of 260 days according to the Kaplan-Meier survival analysis. No major complications occurred. TLPP between AVFs and AVGs (311 vs. 237 days, respectively; p = 0.29) and de novo and restenotic lesions was similar (270.5 vs. 267.5 days, respectively; p = 0.50). In 14 cases, in which lesions were treated with two PCB angioplasties, a statistically significant difference in TLPP after the second treatment was noted (first intervention 179.5 days vs. second intervention 273.5 days; p = 0.032). CONCLUSION: In this retrospective analysis, Lutonix PCB proved to be safe and effective in treating restenosis in dysfunctional dialysis access with results comparable to the literature available. Larger studies are needed to prove abovementioned results.


Assuntos
Angioplastia com Balão/métodos , Fístula Arteriovenosa/terapia , Oclusão de Enxerto Vascular/terapia , Paclitaxel/uso terapêutico , Diálise Renal , Antineoplásicos Fitogênicos/uso terapêutico , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
16.
J Endovasc Ther ; 23(6): 851-863, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27708143

RESUMO

PURPOSE: To report a Bayesian network meta-analysis of randomized controlled trials (RCTs) comparing bare metal stents (BMS), paclitaxel-coated balloons (PCBs), and drug-eluting stents (DES) with balloon angioplasty (BA) or with each other in the infrapopliteal arteries. METHODS: Sixteen RCTs comprising 1805 patients with 1-year median follow-up were analyzed. Bayesian random effects binomial models were employed (WinBUGS). Relative treatment effects were expressed as odds ratios (ORs) with 95% credible intervals (CrI), and the cumulative rank probabilities were calculated to provide hierarchies of competing treatments. Quality of evidence (QoE) was assessed with the GRADE (grading of recommendations assessment, development, and evaluation) system. Sensitivity, heterogeneity, and consistency analyses were performed. RESULTS: There was high QoE that infrapopliteal DES significantly reduced restenosis compared with BMS (OR 0.26, 95% CrI 0.12 to 0.51) and BA (OR 0.22, 95% CrI 0.11 to 0.45). Likewise, DES significantly reduced target lesion revascularization (TLR) compared with BA (OR 0.41, 95% CrI 0.22 to 0.75) and BMS (OR 0.26, 95% CrI 0.15 to 0.45). Paclitaxel-coated balloons also reduced TLR compared with BA (OR 0.55, 95% CrI 0.34 to 0.90) and BMS (OR 0.35, 95% CrI 0.18 to 0.67), but QoE was low to moderate. BA had lower TLR than BMS (OR 0.63, 95% CrI 0.40 to 0.99) with high QoE. DES was the only treatment that significantly reduced limb amputations compared with BA (OR 0.58, 95% CrI 0.35 to 0.96), PCB (OR 0.51, 95% CrI 0.26 to 0.98), or BMS (OR 0.38, 95% CrI 0.19 to 0.72) with moderate to high QoE. DES also significantly improved wound healing compared with BA (OR 2.02, 95% CrI 1.01 to 4.07) or BMS (OR 3.45, 95% CrI 1.41 to 8.73) with high QoE. Results were stable on sensitivity and meta-regression analyses without any significant publication bias or inconsistency. CONCLUSION: Infrapopliteal DES were associated with significantly lower rates of restenosis, TLR, and amputations and improved wound healing compared to BA and BMS. DES also significantly reduced amputations compared with PCB.


Assuntos
Angioplastia com Balão/instrumentação , Fármacos Cardiovasculares/administração & dosagem , Materiais Revestidos Biocompatíveis , Stents Farmacológicos , Metais , Doença Arterial Periférica/terapia , Artéria Poplítea , Stents , Dispositivos de Acesso Vascular , Amputação Cirúrgica , Angioplastia com Balão/efeitos adversos , Teorema de Bayes , Fármacos Cardiovasculares/efeitos adversos , Pesquisa Comparativa da Efetividade , Constrição Patológica , Humanos , Salvamento de Membro , Cadeias de Markov , Metanálise em Rede , Razão de Chances , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Artéria Poplítea/fisiopatologia , Desenho de Prótese , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular , Cicatrização
17.
Expert Rev Med Devices ; 13(12): 1119-1126, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27791450

RESUMO

INTRODUCTION: Percutaneous transcatheter balloon angioplasty has evolved to the current mainstay treatment for salvage of dysfunctional dialysis access. Nonetheless, it is frequently associated with recurrent vessel restenosis and the need for multiple repeat treatments in order to maintain hemodynamic patency. Cutting-balloons, covered stents or stent-grafts, and paclitaxel-coated balloons have been extensively tested and investigated with the aim to improve immediate anatomical and long-term clinical results. Areas covered: In the present overview, we discuss the background and appraise relevant medical literature on the aforementioned technologies and provide a more in-depth synthesis of the results of different clinical studies for each device category. We will also discuss the limitations in the mode of action of each group of devices and envision what the future holds for the challenging field of dialysis access interventions. Expert commentary: We propose a good practice algorithm for the treatment of thrombosed or dysfunctional dialysis access.


Assuntos
Angioplastia com Balão , Materiais Revestidos Biocompatíveis/farmacologia , Paclitaxel/farmacologia , Diálise Renal , Stents , Ensaios Clínicos como Assunto , Humanos
18.
Diagn Interv Radiol ; 22(6): 542-547, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27641942

RESUMO

PURPOSE: Direct superficial femoral artery (SFA) antegrade puncture is a valid alternative to common femoral artery (CFA) access for peripheral vascular interventions. Data investigating vascular closure device (VCD) hemostasis of distant SFA 6F access are limited. We aimed to investigate the safety and effectiveness of the Starclose SE® VCD for hemostasis, following direct 6F antegrade SFA access distal to the femoral head. METHODS: This prospective, single-center study included patients who were not suitable for CFA puncture and were scheduled to undergo peripheral endovascular interventions using direct antegrade SFA 6F access, at least 2 cm below the inferior edge of femoral head. Hemostasis was obtained with the Starclose SE® VCD (Abbott Laboratories). Primary endpoints were successful hemostasis rate and periprocedural (30-day) major complication rate. Secondary endpoint was the rate of minor complications. Clinical and Doppler ultrasound follow-up was performed at discharge and at one month. RESULTS: Between September 2014 and August 2015, a total of 30 patients (21 male; 70.0%) with a mean body mass index of 41.2 kg/m2 were enrolled. Mean age was 72±9 years (range, 67-88 years). Most patients suffered from critical limb ischemia (87.1%) and diabetes (61.3%). Calcifications were present in eight cases (26.6%). Reason for direct SFA puncture was obesity (100%). Successful hemostasis was achieved in 100% of the cases. No major complications were noted after one-month follow-up. Minor complications included two <5 cm hematomas (6.6%) not necessitating treatment. CONCLUSION: In this prospective study, Starclose SE® VCD was safe and effective for hemostasis of antegrade direct SFA puncture. Uncomplicated hemostasis was achieved even in cases of puncturing 2 to 7 cm below the inferior edge of the femoral head.


Assuntos
Procedimentos Endovasculares/instrumentação , Artéria Femoral/cirurgia , Obesidade/complicações , Idoso , Idoso de 80 Anos ou mais , Feminino , Artéria Femoral/diagnóstico por imagem , Hemostasia , Humanos , Masculino , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Ultrassonografia de Intervenção , Dispositivos de Oclusão Vascular
19.
Med Phys ; 43(3): 1428-36, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26936727

RESUMO

PURPOSE: Classify chronic liver disease (CLD) from ultrasound shear-wave elastography (SWE) imaging by means of a computer aided diagnosis (CAD) system. METHODS: The proposed algorithm employs an inverse mapping technique (red-green-blue to stiffness) to quantify 85 SWE images (54 healthy and 31 with CLD). Texture analysis is then applied involving the automatic calculation of 330 first and second order textural features from every transformed stiffness value map to determine functional features that characterize liver elasticity and describe liver condition for all available stages. Consequently, a stepwise regression analysis feature selection procedure is utilized toward a reduced feature subset that is fed into the support vector machines (SVMs) classification algorithm in the design of the CAD system. RESULTS: With regard to the mapping procedure accuracy, the stiffness map values had an average difference of 0.01 ± 0.001 kPa compared to the quantification results derived from the color-box provided by the built-in software of the ultrasound system. Highest classification accuracy from the SVM model was 87.0% with sensitivity and specificity values of 83.3% and 89.1%, respectively. Receiver operating characteristic curves analysis gave an area under the curve value of 0.85 with [0.77-0.89] confidence interval. CONCLUSIONS: The proposed CAD system employing color to stiffness mapping and classification algorithms offered superior results, comparing the already published clinical studies. It could prove to be of value to physicians improving the diagnostic accuracy of CLD and can be employed as a second opinion tool for avoiding unnecessary invasive procedures.


Assuntos
Diagnóstico por Computador/métodos , Técnicas de Imagem por Elasticidade/métodos , Hepatopatias/diagnóstico por imagem , Fenômenos Mecânicos , Adolescente , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
J Endovasc Ther ; 23(2): 356-70, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26823485

RESUMO

PURPOSE: To provide a qualitative analysis and quantitative synthesis of randomized controlled trials (RCTs) investigating paclitaxel-coated balloons (PCBs) in the femoropopliteal artery. METHODS: PubMed, EMBASE, AMED, Scopus, CENTRAL, online content, and abstracts from international meetings were last screened in April 2015 for eligible RCTs using the PRISMA selection process. Risk of bias was assessed using the Cochrane Collaboration's tool, and quality of evidence was evaluated with the GRADE system. Outcome measures included late lumen loss (LLL) at 6 months and event rates of major limb amputations, binary lesion restenosis, and target lesion revascularization (TLR). Pooled treatment effects were analyzed in a random effects model to account for clinical heterogeneity; the outcomes are presented as the rate ratios (RRs) and their 95% confidence intervals (CIs). Extensive meta-regression was performed to analyze potential confounders. The review was registered in the PROSPERO database (CRD42015023938; www.crd.york.ac.uk/PROSPERO). RESULTS: Eleven RCTs with 1609 subjects (1403 claudicants and 206 patients with critical limb ischemia) with medium-length femoropopliteal lesions (mean range 5.1-11.9 cm) were included. There was consistently high-quality evidence supporting the clear superiority of PCBs in terms of reduced LLL (mean difference -0.89 mm, 95% CI -1.14 to -0.64, p<0.001), less binary restenosis (RR 0.47, 95% CI 0.37 to 0.61, p<0.001), and fewer TLR events (RR 0.33, 95% CI 0.22 to 0.49, p<0.001). Major amputations were rare in both active and control arms (pooled event rate: 0.7%, 95% CI 0.3% to 1.2%). Results were stable across all potential risk modifiers and in the presence of stents as well. There was high-quality evidence that the dose of paclitaxel was related to the magnitude of the treatment effect; standard dose (3.0-µg and 3.5-µg) PCBs were significantly more effective compared with low-dose 2-µg PCB in reducing both restenosis (RR 2.1, 95% CI 1.2 to 3.4, p<0.001) and TLR (RR 2.5, 95% CI 1.9 to 3.8, p<0.001). CONCLUSION: PCBs reduce by more than half the rates of restenosis and TLR in the femoropopliteal artery regardless of stent placement. Biologic effect size may vary according to paclitaxel bioavailability.


Assuntos
Angioplastia com Balão/instrumentação , Fármacos Cardiovasculares/administração & dosagem , Materiais Revestidos Biocompatíveis , Artéria Femoral/efeitos dos fármacos , Paclitaxel/análogos & derivados , Doença Arterial Periférica/terapia , Artéria Poplítea/fisiopatologia , Dispositivos de Acesso Vascular , Amputação Cirúrgica , Angioplastia com Balão/efeitos adversos , Disponibilidade Biológica , Fármacos Cardiovasculares/efeitos adversos , Fármacos Cardiovasculares/farmacocinética , Distribuição de Qui-Quadrado , Constrição Patológica , Desenho de Equipamento , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/fisiopatologia , Humanos , Salvamento de Membro , Razão de Chances , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Paclitaxel/farmacocinética , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Artéria Poplítea/diagnóstico por imagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
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