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1.
J Vasc Interv Radiol ; 35(11): 1644-1654, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39142515

RESUMO

PURPOSE: To assess the technical feasibility and safety of image-guided percutaneous biphasic monopolar pulsed electric field (PEF) ablation of primary and metastatic tumors. MATERIALS AND METHODS: With institutional review board (IRB) approval and Health Insurance Portability and Accountability Act (HIPAA) compliance, this retrospective, single-institution study cohort of 17 patients (mean age, 53.5 years; range, 20-94 years) with overall progressive disease underwent 26 PEF ablation procedures for 30 metastatic (90%) and primary (10%) target lesions in the thorax (n = 20), abdomen (n = 7), and head and neck (n = 3). Concurrent systemic therapy was used in 14 of the 17 patients (82%). Follow-up imaging was scheduled for 1, 3, and 6 months after PEF ablation, and target and off-target lesion sizes were recorded. The overall response was assessed by the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria with imaging immediately before PEF serving as baseline. Adverse events (AEs) were determined by the Society of Interventional Radiology (SIR) classification. RESULTS: PEF ablation procedures were well tolerated and technically feasible for all 17 patients. The mean initial sizes of the target and off-target tumors were 2.6 cm (standard deviation [SD] ± 1.5; range, 0.4-6.9 cm) and 2.2 cm (SD ± 1.1; range, 1.0-5.2 cm), respectively. Overall, 15 of the 30 (50%) target lesions and 12 of the 24 (50%) off-target lesions were unchanged or decreased in size at the patient's last follow-up. Eight patients had overall stable disease (47%) at the last follow-up. Of the 26 AEs, there were 9 mild (35%) and 1 moderate (4%) AE. CONCLUSIONS: All PEF procedures were technically feasible with 1 moderate AE and stable disease for 47% of patients with a median follow-up period of 3 months.


Assuntos
Estudos de Viabilidade , Humanos , Pessoa de Meia-Idade , Idoso , Masculino , Feminino , Adulto , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem , Fatores de Tempo , Neoplasias/patologia , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Radiografia Intervencionista/efeitos adversos , Carga Tumoral , Técnicas de Ablação/efeitos adversos
2.
J Vasc Interv Radiol ; 34(2): 253-260, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36368517

RESUMO

PURPOSE: The objectives of this study were to assess the utility of dynamic contrast-enhanced magnetic resonance (MR) imaging in quantifying parenchymal perfusional changes after embolization and to characterize the association between pharmacokinetic (PK) parameters and final microwave ablation volume. MATERIALS AND METHODS: PK parameters from dynamic contrast-enhanced MR imaging were used to quantify perfusional changes in the liver after transarterial embolization of the right or left lobe in a swine liver model (n = 5). Each animal subject subsequently underwent microwave ablation (60 W for 5 minutes) of the embolized and nonembolized liver lobes. Changes in PK parameters from dynamic contrast-enhanced MR imaging were correlated with their respective final microwave ablation volumes in each liver lobe. RESULTS: Microwave ablation volumes of embolized liver lobes were significantly larger than those of nonembolized liver lobes (28.0 mL ± 6.2 vs 15.1 mL ± 5.2, P < .001). PK perfusion parameters were significantly lower in embolized liver lobes than in nonembolized liver lobes (Ktrans = 0.69 min-1 ± 0.15 vs 1.52 min-1 ± 0.37, P < .001; kep = 0.69 min-1 ± 0.19 vs 1.54 min-1 ± 0.42, P < .001). There was a moderate but significant correlation between normalized kep and ablation volume, with each unit increase in normalized kep corresponding to a 9.8-mL decrease in ablation volume (P = .035). CONCLUSIONS: PK-derived parameters from dynamic contrast-enhanced MR imaging can be used to quantify perfusional changes after transarterial embolization and are directly inversely correlated with final ablation volume.


Assuntos
Embolização Terapêutica , Fígado , Suínos , Animais , Fígado/diagnóstico por imagem , Fígado/cirurgia , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Perfusão , Embolização Terapêutica/efeitos adversos
3.
Dig Dis Sci ; 68(12): 4474-4484, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37864738

RESUMO

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease (NAFLD) has reached pandemic proportions. Early detection can identify at-risk patients who can be linked to hepatology care. The vibration-controlled transient elastography (VCTE) controlled attenuation parameter (CAP) is biopsy validated to diagnose hepatic steatosis (HS). We aimed to develop a novel clinical predictive algorithm for HS using the CAP score at a Veterans' Affairs hospital. METHODS: We identified 403 patients in the Greater Los Angeles VA Healthcare System with valid VCTEs during 1/2018-6/2020. Patients with alcohol-associated liver disease, genotype 3 hepatitis C, any malignancies, or liver transplantation were excluded. Linear regression was used to identify predictors of NAFLD. To identify a CAP threshold for HS detection, receiver operating characteristic analysis was applied using liver biopsy, MRI, and ultrasound as the gold standards. RESULTS: The cohort was racially/ethnically diverse (26% Black/African American; 20% Hispanic). Significant positive predictors of elevated CAP score included diabetes, cholesterol, triglycerides, BMI, and self-identifying as Hispanic. Our predictions of CAP scores using this model strongly correlated (r = 0.61, p < 0.001) with actual CAP scores. The NAFLD model was validated in an independent Veteran cohort and yielded a sensitivity of 82% and specificity 83% (p < 0.001, 95% CI 0.46-0.81%). The estimated optimal CAP for our population cut-off was 273.5 dB/m, resulting in AUC = 75.5% (95% CI 70.7-80.3%). CONCLUSION: Our HS predictive algorithm can identify at-risk Veterans for NAFLD to further risk stratify them by non-invasive tests and link them to sub-specialty care. Given the biased referral pattern for VCTEs, future work will need to address its applicability in non-specialty clinics. Proposed clinical algorithm to identify patients at-risk for NAFLD prior to fibrosis staging in Veteran.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatopatias Alcoólicas , Hepatopatia Gordurosa não Alcoólica , Veteranos , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Técnicas de Imagem por Elasticidade/métodos , Fígado/patologia , Registros Eletrônicos de Saúde , Estudos Prospectivos , Curva ROC , Hepatopatias Alcoólicas/complicações , Biópsia , Cirrose Hepática/diagnóstico
4.
AJR Am J Roentgenol ; 218(4): 699-700, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34704462

RESUMO

Seven patients underwent microwave ablation of hepatic tumors; during ablation, a hepatic nerve plexus block was used for pain control. The mean visual analog scale (VAS) score for pain (scale, 0-10) was 0.3 ± 0.5 (SD) at baseline and 2.5 ± 1.4, 2.6 ± 1.4, and 2.3 ± 0.9 at 1, 5, and 10 minutes during ablation. Two patients reported a VAS score of 4 or greater during ablation, which improved in both patients to a VAS score of 3 after one rescue sedation dose. The remaining patients required no additional sedation. No major complication occurred. No patient required conversion to general anesthesia.


Assuntos
Neoplasias Hepáticas , Bloqueio Nervoso , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Micro-Ondas/uso terapêutico , Dor/etiologia , Medição da Dor/efeitos adversos
5.
J Vasc Interv Radiol ; 29(5): 628-631, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29685660

RESUMO

Open repair of ascending aortic pseudoaneurysms (AAPs) is currently the standard of care, but it is associated with high morbidity and mortality. A single-center retrospective experience of 4 patients after cardiac surgery undergoing 5 percutaneous transthoracic embolization procedures is presented. In 3 of the 4 patients, the primary outcome of complete thrombosis was achieved after the first procedure, with a mean follow-up time of 11.5 months. In all 5 procedures, the patients tolerated the procedure well without associated acute complications. Percutaneous transthoracic embolization of AAPs offers an alternate minimally invasive treatment pathway for prohibitive-risk candidates.


Assuntos
Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/cirurgia , Aorta/diagnóstico por imagem , Aorta/cirurgia , Procedimentos Endovasculares/métodos , Imagem Multimodal , Idoso , Angiografia , Ecocardiografia Transesofagiana , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
6.
AJR Am J Roentgenol ; 204(5): 974-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25905930

RESUMO

OBJECTIVE: The purpose of this article is to review the origins of the classic teaching on pulmonary tuberculosis, its evolution in the modern literature, and the evidence that led to its demise. CONCLUSION: Use of molecular epidemiologic techniques that entail DNA finger-printing has led to the discovery that the radiographic appearance of pulmonary tuberculosis does not depend on the time since infection. It has been confirmed that the upper lobe cavitary disease typical in adults is the disease of the immunocompetent host, whereas lower lung zone disease, adenopathy, and effusions, which are uncommon in adults, are the hallmarks of tuberculosis in an immunocompromised host.


Assuntos
Radiografia Torácica , Tuberculose Pulmonar/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Epidemiologia Molecular , Tuberculose Pulmonar/epidemiologia
7.
Radiology ; 267(2): 596-601, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23297330

RESUMO

PURPOSE: To evaluate how interreader agreement and the site of the volume of interest (VOI) affect the agreement and variability of liver mean standardized uptake value normalized to lean body mass (SUL(mean)) at fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT). MATERIALS AND METHODS: Institutional review board approval was obtained for this HIPAA-compliant retrospective review of PET/CT images and patient records. PET/CT images were reviewed in 116 randomly selected patients who had undergone a baseline PET/CT examination and who had normal livers according to imaging and biochemical test results. A 30-mm-diameter spherical VOI was placed within the right lobe of the liver above, below, and at the level of the main portal vein. Two readers performed all measurements independently. Analysis of variance, intraclass correlation coefficient (ICC) analysis, and Bland-Altman analysis were performed. RESULTS: The mean SUL(mean) was between 2.11 and 2.17 at the upper, portal, and lower levels of the right lobe of the liver. The coefficient of variance was between 21.0% and 23.1%, without significant differences for location, with the least variance in the upper level. The ICC of the two readers varied between 0.98 and 0.99 (95% confidence interval [CI]: 0.97, 0.99; P = .0001) at each level. The greatest precision (narrowest CI) was also in the upper level. Bias was 0.025 ± 0.10 (standard deviation) at the upper level, was 0.004 ± 0.14 at the lower level, and was 0.047 ± 0.10 at the portal vein (P = .02). For each reader, there was almost perfect reliability between the SUL(mean) measurements made at the three levels, with an ICC of 0.98 (95% CI: 0.98, 0.99; P = .0001). CONCLUSION: Liver SUL(mean) at FDG PET/CT has excellent interreader agreement, with similar values and variance whether measured at the upper, lower, or portal vein levels within the right lobe of the liver.


Assuntos
Fluordesoxiglucose F18/farmacocinética , Fígado/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/farmacocinética , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos
8.
Diagn Interv Radiol ; 29(6): 805-812, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37665139

RESUMO

PURPOSE: To evaluate the efficacy of combination therapy using transarterial chemoembolization with microwave ablation (MWA) therapy vs. MWA monotherapy for hepatocellular carcinomas (HCCs) >3 cm in size. METHODS: This two-arm retrospective observational study included patients with HCCs >3 cm who underwent either combination therapy (29 patients) or MWA monotherapy (35 patients) between 2014 and 2020. The treatment outcomes related to primary treatment efficacy, local tumor progression (LTP), tumor control rate, and overall survival were compared between each cohort. RESULTS: The technical success and primary efficacy were 96.56% and 100.00% in the combination therapy cohort, and 91.42% and 100.00% in the MWA cohort, respectively, over a mean follow-up period of 27.6 months. The 1- and 3-year rates of LTP-free survival were 78.57% and 69.56% in the combination therapy cohort, vs. 72.45% and 35.44% in the MWA cohort, respectively (P = 0.001). The overall progression-free survival was longer in the combination therapy cohort compared with the MWA cohort (median: 56.0 vs. 13.0 months; P = 0.017). With the incorporation of additional locoregional therapy, the overall survival rates were not significantly different, with 1- and 3-year overall survival rates of 100.00% and 88.71% in the combination therapy cohort and rates of 90.15% and 82.76% in the MWA cohort, respectively (P = 0.235). CONCLUSION: The combination therapy provided significantly longer upfront LTP-free survival in HCCs >3 cm when compared with the MWA treatment alone, albeit with similar local tumor control and overall survival rates when accounting for additional locoregional therapies.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Quimioembolização Terapêutica , Neoplasias Hepáticas , Ablação por Radiofrequência , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/patologia , Micro-Ondas/uso terapêutico , Resultado do Tratamento , Estudos Retrospectivos
9.
Accid Anal Prev ; 173: 106708, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35640365

RESUMO

As the automobile market gradually develops towards intelligence, networking, and information-orientated, intelligent identification based on connected vehicle data becomes a key technology. Specifically, real-time crash identification using vehicle operation data can enable automotive companies to obtain timely information on the safety of user vehicle usage so that timely customer service and roadside rescue can be provided. In this paper, an accurate vehicle crash identification algorithm is developed based on machine learning techniques using electric vehicles' operation data provided by SAIC-GM-Wuling. The point of battery disconnection is identified as a potential crash event. Data before and after the battery disconnection is retrieved for feature extraction. Two different feature extraction methods are used: one directly extracts the descriptive statistical features of various variables, and the other directly unfolds the multivariate time series data. The AdaBoost algorithm is used to classify whether a potential crash event is a real crash using the constructed features. Models trained with the two different features are fused for the final outputs. The results show that the final model is simple, effective, and has a fast inference speed. The model has an F1 score of 0.98 on testing data for crash classification, and the identified crash times are all within 10 s around the true crash times. All data and code are available at https://github.com/MeixinZhu/vehicle-crash-identification.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Acidentes de Trânsito/prevenção & controle , Algoritmos , Automóveis , Humanos , Tecnologia
10.
Life (Basel) ; 11(7)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201468

RESUMO

Background: The purpose of this study is to describe a single institution's experience using Oncozene (OZ) microspheres for transarterial chemoembolization (OZ-TACE) of hepatocellular carcinoma (HCC), and to compare tolerability, safety, short-term radiographic tumor response, progression-free survival (PFS), and overall survival (OS) of these procedures to TACE (LC-TACE) performed with LC beads (LC). Methods: A retrospective, matched cohort study of patients undergoing DEB-TACE (drug-eluting bead transarterial chemoembolization) with OZ or LC was performed. The cohort comprised 23 patients undergoing 29 TACE with 75 or 100 µm OZ and 24 patients undergoing 29 TACE with 100-300 µm LC. Outcome measures were changes in liver function tests, complications, treatment tolerability, short-term radiographic tumor response according to modified RECIST criteria for HCC, PFS, and 1-year OS. The Mann-Whitney U test, Fisher exact test, and log rank test were used to compare the groups. Results: The BCLC or Child-Pugh scores were similar between the OZ and LC group. However, the two groups differed with respect to the etiology of background cirrhosis (p = 0.02). All other initial demographic and tumor characteristics were similar between the two groups. OZ-TACE used less doxorubicin per treatment compared to LC-TACE (median 50 vs. 75 mg; p = 0.0005). Rates of pain, nausea, and postembolization syndrome were similar, irrespective of the embolic agent used. OZ-TACE resulted in an overall complication rate comparable to LC-TACE (20.7% vs. 10.3%; p = 0.47). LC-TACE resulted in a higher percent increase in total bilirubin on post-procedure day 1 (median 18.8 vs. 0%; p = 0.05), but this difference resolved at 1 month. Both OZ-TACE and LC-TACE resulted in similar complete (31% vs. 24%) and objective (66% vs. 79%) target lesion response rates on 1-month post-TACE imaging. Both OZ-TACE and LC-TACE had similar median progression-free survival (283 vs. 209 days; p = 0.14) and 1-year overall survival rates (85% vs. 76%; p = 0.30). Conclusion: With a significantly reduced dose of doxorubicin, TACE performed with Oncozene microspheres in a heterogeneous patient population is well-tolerated, safe, and produces a similar radiological response and survival rate when compared to LC Bead TACE.

11.
Tech Vasc Interv Radiol ; 21(2): 65-77, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29784124

RESUMO

Thromboses of the superior and inferior vena cava, either isolated or associated with distal deep venous thrombosis, are uncommon, but confer potentially serious morbidity and mortality. Incidence is increasing, especially with the prominence of intravascular devices. The range of treatment options is also expanding to include medical management, surgery, and endovascular techniques which are now frequently considered first line therapy due to lower reintervention rates and decreased periprocedural morbidity. Currently, there are no official guidelines for screening or treatment. This article reviews the etiology, diagnosis, and management of caval thromboses, including equipment, procedural steps, outcomes, and complications, particularly with regard to endovascular techniques, such as catheter-directed thrombolysis, pharmacomechanical catheter-directed thrombolysis, angioplasty, and stenting.


Assuntos
Procedimentos Endovasculares/métodos , Fibrinolíticos/administração & dosagem , Trombectomia/métodos , Terapia Trombolítica/métodos , Veia Cava Inferior , Veia Cava Superior , Trombose Venosa/terapia , Angiografia Digital , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Fibrinolíticos/efeitos adversos , Humanos , Flebografia/métodos , Trombectomia/efeitos adversos , Trombectomia/instrumentação , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/instrumentação , Resultado do Tratamento , Veia Cava Inferior/anormalidades , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/fisiopatologia , Veia Cava Superior/anormalidades , Veia Cava Superior/diagnóstico por imagem , Veia Cava Superior/fisiopatologia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/fisiopatologia
12.
Materials (Basel) ; 11(11)2018 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-30423884

RESUMO

In this study, the effect of austenite grain size on acicular ferrite (AF) nucleation in low-carbon steel containing 13 ppm Mg is determined. The average austenite grain size was calculated using OM Leica software. Results show that the predicted and experimental values of austenite grain size are extremely close, with a deviation of less than 20 µm. AF formation is difficult to induce by either excessively small and large austenite grain sizes; that is, an optimal austenite grain size is required to promote AF nucleation probability. The austenite grain size of 164 µm revealed the highest capacity to induce AF formation. The effects of the maximum distance of carbon diffusion and austenite grain size on the microstructure of Mg-containing low carbon steel are also discussed. Next, the pinning ability of different inclusion types in low-carbon steel containing 22 Mg is determined. The in situ observation shows that not every inclusion could inhibit austenite grain migration; the inclusion type influences pinning ability. The grain mobility of each inclusion was calculated using in situ micrographs of confocal scanning laser microscopy (CSLM) for micro-analysis. Results show that the austenite grain boundary can strongly be pinned by Mg-based inclusions. MnS inclusions are the least effective in pinning austenite grain boundary migration.

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