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Assess carotid artery strain and motion in people living with HIV as markers of premature aging using ultrasound noninvasive vascular elastography (NIVE). Seventy-four HIV-infected and 75 age-matched control subjects were recruited from a prospective, controlled cohort study from October 2015 to October 2017 (mean age 56 years ± 8 years; 128 men). NIVE applied to longitudinal ultrasound images of common and internal carotid arteries quantified the cumulated axial strain, cumulated shear strain, cumulated axial translation, and cumulated lateral translations. The presence of plaque was also assessed. An association between elastography biomarkers and HIV status was evaluated with Mann–Whitney tests and multivariable linear regression models. A higher occurrence of carotid artery plaques was found in HIV-infected individuals (p = 0.011). Lower cumulated lateral translations were found in HIV-infected subjects on both common and internal carotid arteries (p = 0.037 and p = 0.026, respectively). These observations remained significant when considering multivariable models including common cardiovascular risk factors and clinical characteristics (p

Coronary plaques are reported as one of the primary causes of death in the developed world. A simple fractional flow reserve measurement is insufficient for assessing the functional severit...

Evaluate non-invasive vascular elastography (NIVE) in detecting vascular changes associated with obese children. Case-control study to evaluate NIVE in 120 children, 60 with elevated body mass index (BMI) (≥ 85th percentile for age and sex). Participants were randomly selected from a longitudinal cohort, evaluating consequences of obesity in healthy children with one obese parent. Radiofrequency ultrasound videos of the common carotid artery were obtained. The carotid wall was segmented and NIVE applied to measure cumulated axial strain (CAS), cumulated axial translation (CAT), cumulated lateral translation (CLT), maximal shear strain (Max |SSE|), and intima-media thickness (IMT). Multivariate analyses were used controlling for age, sex, Tanner stage, blood pressure, and low-density lipoprotein. Statistical significance was set to 0.05–0.008. Participants were 10–13 years old (mean 11.4 and 12.0, for normal and elevated BMI groups, p

Quantitative ultrasound (QUS) imaging methods, including elastography, echogenicity analysis, and speckle statistical modeling, are available from a single ultrasound (US) radio-frequency data acquisition. Since these US imaging methods provide complementary quantitative tissue information, characterization of carotid artery plaques may gain from their combination. Sixty-six patients with symptomatic ( $n = 26$ ) and asymptomatic ( $n = 40$ ) carotid atherosclerotic plaques were included in the study. Of these, 31 underwent magnetic resonance imaging (MRI) to characterize plaque vulnerability and quantify plaque components. US radio-frequency data sequence acquisitions were performed on all patients and were used to compute noninvasive vascular US elastography and other QUS features. Additional QUS features were computed from three types of images: homodyned-K (HK) parametric maps, Nakagami parametric maps, and log-compressed B-mode images. The following six classification tasks were performed: detection of 1) a small area of lipid; 2) a large area of lipid; 3) a large area of calcification; 4) the presence of a ruptured fibrous cap; 5) differentiation of MRI-based classification of nonvulnerable carotid plaques from neovascularized or vulnerable ones; and 6) confirmation of symptomatic versus asymptomatic patients. Feature selection was first applied to reduce the number of QUS parameters to a maximum of three per classification task. A random forest machine learning algorithm was then used to perform classifications. Areas under receiver-operating curves (AUCs) were computed with a bootstrap method. For all tasks, statistically significant higher AUCs were achieved with features based on elastography, HK parametric maps, and B-mode gray levels, when compared to elastography alone or other QUS alone ( $p ). For detection of a large area of lipid, the combination yielding the highest AUC (0.90, 95% CI 0.80–0.92, $p ) was based on elastography, HK, and B-mode gray-level features. To detect a large area of calcification, the highest AUC (0.95, 95% CI 0.94–0.96, $p ) was based on HK and B-mode gray level features. For other tasks, AUCs varied between 0.79 and 0.97. None of the best combinations contained Nakagami features. This study shows the added value of combining different features computed from a single US acquisition with machine learning to characterize carotid artery plaques.

Off-label drug prescribing, frequent in the treatment of vascular anomalies (VA), relies on the quality of the literature reporting drug efficacy and safety. Our objective is to review the level of evidence (LOE) surrounding drug use in VA, which is more prevalent in pediatric care. A list of drugs used in VA was created with a literature review in July 2020. For each drug listed, the article displaying the highest LOE was determined and then compared between efficacy/safety data, routes of administration, pharmacological categories and a subset of VA. The influence of research quality on study results was also explored. The median LOE for the 74 drugs identified poor methodological quality, with a predominance of retrospective studies or case reports. Drug safety is currently inadequately reported. This is alarming as many treatments display significant safety concerns. Also, current literature displays major publication bias that probably leads to overestimation of drug efficacy in VA.

To compare the mechanical properties of aneurysm content after endoleak embolization with a chitosan hydrogel (CH) with that with a chitosan hydrogel with sodium tetradecyl sulfate (CH-STS) using strain ultrasound elastography (SUE).Bilateral common iliac artery type Ia endoleaks were created in 9 dogs. Per animal, 1 endoleak was randomized to blinded embolization with CH, and the other, with CH-STS. Brightness-mode ultrasound, Doppler ultrasound, SUE radiofrequency ultrasound, and computed tomography were performed for up to 6 months until sacrifice. Radiologic and histopathologic studies were coregistered to identify 3 regions of interest: the embolic agent, intraluminal thrombus (ILT), and aneurysm sac. SUE segmentations were performed by 2 blinded independent observers. The maximum axial strain (MAS) was the primary outcome. Statistical analysis was performed using the Fisher exact test, multivariable linear mixed-effects models, and intraclass correlation coefficients (ICCs).Residual endoleaks were identified in 7 of 9 (78%) and 4 of 9 (44%) aneurysms embolized with CH and CH-STS, respectively (P = .3348). CH-STS had a 66% lower MAS (P.001) than CH. The ILT had a 37% lower MAS (P = .01) than CH and a 77% greater MAS (P = .079) than CH-STS. There was no significant difference in ILT between treatments. The aneurysm sacs embolized with CH-STS had a 29% lower MAS (P.001) than those embolized with CH. Residual endoleak was associated with a 53% greater MAS (P.001). The ICC for MAS was 0.807 (95% confidence interval: 0.754-0.849) between segmentations.CH-STS confers stiffer intraluminal properties to embolized aneurysms. Persistent endoleaks are associated with increased sac strain, an observation that may help guide management.

International audience; Purpose Microspheres are effective embolic agents, especially for the management of bleeding and oncologic lesions. The first FairEmbo study reported the effectiveness of embolization using suture fragments. The effectiveness and safety of arterial embolization with suture-based microparticles (SBM) were assessed in a swine model.Materials and Methods In this ethical-approved animal study, a polar artery in each kidney was embolized in four swine: one side with hand-cut non-absorbable SBM (Flexocrin 2®) and the contralateral side with Embozene® 900 for comparison. Swine were followed for 3 months (M3) to evaluate the effectiveness and the safety of SBM. Follow-up protocol included clinical monitoring, computed tomography (CT) control and digital subtraction angiography (DSA), followed by histological analyses. The SBM confection parameters were evaluated by automatic microscopic sizer. RStudio software and Mann–Whitney test (significance at P

Motion estimation of biological tissues, including displacement and strain estimations, is important as it provides biomarkers of tissue kinetic abnormalities. Since tissue motions are in 3D, 3D motion estimation can avoid out-of-plane artifacts which is usually encountered using 2D motion tracking methods. In this study, we propose a 3D motion tracking method which is able to simultaneously estimate displacement and strain fields using B-mode data. The proposed method is firstly validated using a cardiac simulation dataset. It is shown that it is able to identify known cardiac ischemic lesions where present less strain magnitudes. For the in vivo test, 4D ultrasound B-mode scan of an abdominal aorta was performed on a healthy volunteer using a clinical system. The approach allows to represent the pulsation of the aorta wall, and to quantify discrete strain fields.

Purpose To assess whether angioplasty of hemodialysis access (HA) stenosis with a drug-coated balloon (DCB) would prevent restenosis in comparison with plain-balloon percutaneous transluminal angioplasty (PTA). Materials and Methods This prospective randomized clinical trial enrolled 120 patients with dysfunctional arteriovenous fistulae (n = 109) and grafts (n = 11), due to a ≥50% stenosis between March 2014 and April 2018. All patients underwent high-pressure balloon angioplasty and were then randomized to either DCB (n = 60) or PTA (n = 60). Patients were followed-up for 1 year, and angiography was performed 6 months after angioplasty. The primary endpoint was the late lumen loss (LLL) at 6 months. Secondary endpoints included other angiographic parameters at 6 months and HA failures, adverse event, and mortality at 12 months. Continuous variables were compared with a Student t-test, and Kaplan-Meier curves were used for freedom from HA failure and for mortality. Results LLL in the DCB and in the PTA group were 0.64 mm ± 1.20 and 1.13 mm ± 1.51, respectively (P = .082, adjusted P = .0498). DCB was associated with lower percentage stenosis (54.2% ± 19.3 vs 61.7% ± 18.2; P = .047) and binary restenosis ≥50% (56.5% vs 81.1%; P = .009) than PTA. The number of HA failures after 12 months was lower for DCB than for PTA (45% vs 66.7%; P = .017). Mortality at 12 months was 10% and 8.3% in the DCB and PTA groups, respectively (P = .75). Conclusions Despite LLL improvement that failed to reach statistical significance, this study demonstrated decreased incidence and severity of restenosis with DCB compared with PTA to treat dysfunctional HA.

Background Adrenal vein sampling (AVS) failure is mainly due to right adrenal vein unavailability. Multinomial regression modelling (MRM) and left adrenal vein-to-peripheral vein ratio (LAV/PV) were proposed to predict the lateralization index without the right AVS. Objective To assess external validity of MRM and LAV/PV to predict lateralization index when right adrenal vein sampling is missing. Design Diagnostic retrospective study. Patients Development and validation cohorts included AVS of 174 and 122 patients, respectively, from 2 different centres. Measurements Development and validation cohort data were used, respectively, for calibration and for validation of MRM and LAV/PV to predict the lateralization index without the right adrenal vein sampling. Sensitivity and specificity of MRM and LAV/PV were compared between both centres at different pre-established specificity thresholds based on receiver operating characteristic curves generated from the development cohort data. Results At a specificity threshold of 95% set in the development cohort, specificity values exceeded 90% (range, 90.6%-98.8%) for all verified MRM and LAV/PV models in the validation cohort. Corresponding sensitivities for MRM and LAV/PV, respectively, range from 54.1% to 83.7% and 32.8% to 88.4% for the development cohort compared to 33.3%-87.5% and 2.8%-79.2% for the validation cohort. Overall, diagnostic accuracy of both methods was higher to detect right (82.8%-93.5%) than left (70.2%-80.6%) lateralization index status in both centres. Conclusions Minimal changes in specificity from development to validation cohorts validate the use of MRM and LAV/PV to predict the lateralization index when the right AVS is missing. Both methods had better accuracy for right than left lateralization detection.

Droplet microfluidics technology has recently been introduced to generate particles for many biomedical applications that include therapeutic embolizing agents in hepatic, uterine or bronchial arteries. Embolic agents are available in a variety of shapes and sizes that are adjusted according to the target vessel characteristics. Magnetic embolic agents can additionally be navigated to the target location (e.g., a tumor) through the blood system by applying an external magnetic field. This technology is termed Magnetic Resonance Navigation (MRN). Here we introduce a high throughput method to produce homogeneously sized magnetic microspheres (MMS) as blood vessel embolic agents for use in combination with MRN. The system for MMS production consists of a simple 3D printed micro coflowing device that is able to produce biocompatible, degradation rate controllable poly(lactic-co-glycolic acid) (PLGA) microspheres encasing magnetic nanoparticles. Axisymmetric flow is obtained with a central needle injecting the dispersed phase surrounded by a continuous phase and leads to the formation of size-controlled droplets that turn into homogeneously sized MMS linearly dependent on the inner needle diameter. MMS morphology, mean particle size and size distribution were quantified from SEM images. Magnetic performance of MMS was investigated using a vibrating sample magnetometer. MMS were nontoxic toward HUVEC (human umbilical vein endothelial cells) and HEK293 (human embryonic kidney) cells. The presented micro coflowing method allows for the reliable production of large MMS sized 130-700 μm with narrow size distribution (CV < 7%) and magnetic properties useful for MRN.

Objective To assess the prevalence and clinical significance of incidental findings identified during computed tomography imaging of coronary artery bypass grafts. Results This prospective study includes 144 patients undergoing coronary graft patency assessment using computed tomography. Incidental findings were classified as significant if they were considered to need an immediate action or treatment, short-term work-up or follow-up, or minor. A total of 211 incidental findings were present in 109 (75.7%) patients. Seventy-one incidental findings (33.6%) were cardiac and 140 (66.4%) were extracardiac. Most common cardiac incidental findings were atrial dilatation [39 patients, 48 incidental findings (67.6%)] and aortic valve calcifications (7 patients, 9.9%). Among the 140 extracardiac incidental findings, the most common were lung nodules (51 patients, 54 nodules, 38.6%), and emphysema (21 patients, 15%). Thirty-six (25.7%) extracardiac incidental findings were significant and notably, 23 (63.9%) were lung nodules. Follow-up was recommended in 37 cases, among which all patients with significant lung nodules (23 patients, 62.2%). In conclusion, most common computed tomography incidental findings in patients with coronary grafts were lung nodules and emphysema. Electronic supplementary material The online version of this article (10.1186/s13104-018-3168-1) contains supplementary material, which is available to authorized users.

The success of endovascular repair of abdominal aortic aneurysms remains limited due to the development of endoleaks. Sac embolization has been proposed to manage endoleaks, but current embolizing materials are associated with frequent recurrence. An injectable agent that combines vascular occlusion and sclerosing properties has demonstrated promise for the treatment of endoleaks. Moreover, the inhibition of aneurysmal wall degradation via matrix metalloproteinases (MMPs) may further prevent aneurysm progression. Thus, an embolization agent that promotes occlusion, MMP inhibition and endothelial ablation was hypothesized to provide a multi-faceted approach for endoleak treatment. In this study, an injectable, occlusive chitosan (CH) hydrogel containing doxycycline (DOX)—a sclerosant and MMP inhibitor—was developed. Several CH-DOX hydrogel formulations were characterized for their mechanical and sclerosing properties, injectability, DOX release rate, and MMP inhibition. An optimized formulation was assessed for its short-term ability to occlude blood vessels in vivo . All formulations were injectable and gelled rapidly at body temperature. Only hydrogels prepared with 0.075 M sodium bicarbonate and 0.08 M phosphate buffer as the gelling agent presented sufficient mechanical properties to immediately impede physiological flow. DOX release from this gel was in a two-stage pattern: a burst release followed by a slow continuous release. Released DOX was bioactive and able to inhibit MMP-2 activity in human glioblastoma cells. Preliminary in vivo testing in pig renal arteries showed immediate and delayed embolization success of 96% and 86%, respectively. Altogether, CH-DOX hydrogels appear to be promising new multifunctional embolic agents for the treatment of endoleaks. Statement of Significance An injectable embolizing chitosan hydrogel releasing doxycycline (DOX) was developed as the first multi-faceted approach for the occlusion of blood vessels. It combines occlusive properties with DOX sclerosing and MMP inhibition properties, respectively known to prevent recanalization process and to counteract the underlying pathophysiology of vessel wall degradation and aneurysm progression. After drug release, the biocompatible scaffold can be invaded by cells and slowly degrade. Local DOX delivery requires lower drug amount and decreases risks of side effects compared to systemic administration. This new gel could be used for the prevention or treatment of endoleaks after endovascular aneurysm repair, but also for the embolization of other blood vessels such as venous or vascular malformations.

Arteriovenous malformations (AVMs) are high-flow vascular anomalies that have demonstrated a very high recurrence rate after endovascular treatment, surgical treatment, or a combination of both. Surgical treatments have shown good response when they are small and well localized but a poor response when diffuse. A better understanding of the nature of the lesion has led to a better response rate and a safer treatment for these patients. This has been accomplished through a detailed understanding of the angioarchitecture of the lesion, enabling a tailored approach in reaching and targeting the nidus of the AVM with different liquid embolic agents, more specifically ethanol. Flow reduction techniques help in exposing the nidus to sclerosant agents. A clinical classification, the Schobinger classification, will help determine the appropriate time to start or to pursue therapy.

We present the elastic and viscoelastic characterization of aortic tissue and a synthetic material used for the fabrication of artificial vessels (Dacron). Using biaxial, high deformation and oscillating mechanical testing protocols, we assessed the hyperelastic and viscoelastic properties of both aortic tissue and Dacron. Energy loss is a viscous measure of energy absorbed by a material during deformation. It provides information of the materials time dependence and capacity to dissipate energy. Investigation of the correlation between smooth muscle cell (SMC) content and energy loss within healthy and aneurysmal aortic tissue was carried out via biaxial tensile testing of aortic tissue samples. The results of aortic tissue energy loss investigation show that an acceptable correlation exists between the presence of SMCs and the magnitude of energy loss. In addition, our data suggests that the condition and organization of SMCs may affect the viscous behaviour of tissue, instead of their mere presence. The results of the high deformation and oscillating mechanical testing show significant differences between the biological and the synthetic materials. Histologic examination of selected samples revealed healthy tissue was characterized by higher elastin content, 45.3±2.07% vs. 39.78±1.84%. Aneurysmal tissue was found to have greater SMC content in comparison to healthy tissue.

Arteriovenous malformations (AVMs) are fast flow malformations characterized by the presence of arteriovenous shunting. These congenital lesions can be evolutive, leading to serious complications such as bleeding, skin ulceration, and cardiac failure. The interventional radiologist plays an important role in the management of these patients. He should be involved in the clinical evaluation to make the proper diagnosis, evaluate the symptoms and potential indication for endovascular treatment. This evaluation should be done in a multidisciplinary clinic with access to plastic surgeons, internal medicine and dermatologist, as well as specific specialists that might need to be implicated (ENT surgeon in the face and neck area, for example). The Schobinger clinical classification is important to assess patient evolution and indicate intervention. We recommend to treat symptomatic or evolutive AVMs. Doppler ultrasound is the first imaging examination that should be performed. Then, MR angiography or computed tomography angiography (CTA) can be proposed depending on the anatomic area involved. Embolization is currently the first line of treatment for these patients. There is currently promising research in the identification of genetic markers and molecular target(s) but there is no recognized pharmacologic treatment for AVM available yet. Digital substraction angiography (DSA) is usually performed for guidance during the embolization session but is also essential to properly classify a specific lesion, according to its anatomy. The anatomic classifications proposed by Cho and Yakes are both useful to choose the best therapeutic approach: Endovascular, direct puncture, retrograde venous approach or a combination of these techniques. Ethanol is the most efficient agent but is at higher risk of skin necrosis and nerve injury and should therefore be used with caution in dangerous territories. Glue and Onyx are liquid agents that are also well suited to occlude the nidus; they can be used in association with ethanol. On the venous side, mechanical occlusion with coils or Amplatzer plugs is mostly used. Again, they can be used in association with a liquid agent (Ethanol, glue or Onyx) to reflux in the nidus. Surgery can be indicated to resect residual AVM following embolization if residual symptoms are present and the planned surgery is feasible, with relative safety.

To investigate the feasibility of shear wave sonoelastography (SWS) for endoleak detection and thrombus characterization of abdominal aortic aneurysm (AAA) after endovascular repair (EVAR). Participants who underwent EVAR were prospectively recruited between November 2014 and March 2016 and followed until March 2019. Elasticity maps of AAA were computed using SWS and compared to computed tomography angiography (CTA) and color Doppler ultrasound (CDUS). Two readers, blinded to the CTA and CDUS results, reviewed elasticity maps and B-mode images to detect endoleaks. Three or more CTAs per participant were analyzed: pre-EVAR, baseline post-EVAR, and follow-ups. The primary endpoint was endoleak detection. Secondary endpoints included correlation between total thrombus elasticity, proportion of fresh thrombus, and aneurysm growth between baseline and reference CTAs. A 3-year follow-up was made to detect missed endoleaks, EVAR complication, and mortality. Data analyses included Cohen’s kappa; sensitivity, specificity, and positive predictive value (PPV); Pearson coefficient; and Student’s t tests. Seven endoleaks in 28 participants were detected by the two SWS readers (k = 0.858). Sensitivity of endoleak detection with SWS was 100%; specificity and PPV averaged 67% and 50%, respectively. CDUS sensitivity was estimated at 43%. Aneurysm growth was significantly greater in the endoleak group compared to sealed AAAs. No correlation between growth and thrombus elasticity or proportion of fresh thrombus in AAAs was found. No new endoleaks were observed in participants with SWS negative studies. SWS has the potential to detect endoleaks in AAA after EVAR with comparable sensitivity to CTA and superior sensitivity to CDUS. • Dynamic elastography with shear wave sonoelastography (SWS) detected 100% of endoleaks in abdominal aortic aneurysm (AAA) follow-up that were identified by a combination of CT angiography (CTA) and color Doppler ultrasound (CDUS). • Based on elasticity maps, SWS differentiated endoleaks from thrombi within the aneurysm sac (p

Increased arterial stiffness is one of the first signs of atherosclerosis. The objective of this study was to use non-invasive elastography (NIVE) to detect early changes in vascular biomechanics associated with obesity in children. The NIVE algorithm also measured the intimamedia thickness (IMT) for comparison.NIVE was applied in 120 children, 60 with elevated body mass index (BMI) (≥ 85th percentile for age and sex) and 60 non-overweight (BMI < 85th percentile). Participants were randomly selected from a longitudinal cohort, evaluating consequences of obesity in healthy children with one obese parent. The carotid wall was automatically segmented and elastograms were computed to measure the cumulated axial strain (CAS), cumulated axial translation (CAT), and maximal shear strain (Max |SSE|); IMT was also computed from segmented contours. Elastogram features were compared between groups with multivariate analyses to control for age, sex, Tanner stage, blood pressure, and lowdensity lipoprotein cholesterol (LDL).After Bonferroni correction, CAT was significantly higher in the elevated BMI group (0.68 ± 0.24 mm vs. 0.52 ± 0.18 mm), p < 0.001. CAS/CAT was significantly lower in the elevated BMI group (9.54 ± 4.8 %/mm vs. 13.34 ± 6.46 %/mm), p = 0.001; the lower CAS/CAT ratio suggests stiffer arteries with less deformation for a similar translation.Before Bonferroni correction, IMT was significantly higher in the elevated BMI group (0.36 ± 0.05 mm vs. 0.32 ± 0.05 mm), p = 0.013. IMT statistical difference was no longer significant after Bonferroni correction.After Bonferroni correction, NIVE detected differences in CAT and CAS/CAT biomarkers in elevated BMI children, whereas IMT failed to show a difference. NIVE is a promising technique to monitor radiological biomarkers of subclinical atherosclerosis in the pediatric population.

International audience; Abdominal aortic aneurysms (AAA) are localized, commonly occurring aortic dilations. Following rupture only immediate treatment can prevent morbidity and mortality. AAA maximal diameter and growth are the current metrics to evaluate the associated risk and plan intervention. Although these criteria alone lack patient specificity, predicting their evolution would improve clinical decision. If the disease is known to be associated with altered morphology and blood flow, intraluminal thrombus deposit and clinical symptoms, the growth mechanisms are yet to be fully understood. In this retrospective longitudinal study of 138 scans, morphological analysis and blood flow simulations for 32 patients with clinically diagnosed AAAs and several follow-up CT-scans, are performed and compared to 9 control subjects. Several metrics stratify patients between healthy, low and high risk groups. Local correlations between hemodynamic metrics and AAA growth are also explored but due to their high inter-patient variability, do not explain AAA heterogeneous growth. Finally, high-risk predictors trained with successively clinical, morphological, hemodynamic and all data, and their link to the AAA evolution are built from supervise learning. Predictive performance is high for morphological, hemodynamic and all data, in contrast to clinical data. The morphology-based predictor exhibits an interesting effort-predictability tradeoff to be validated for clinical translation.

Purpose This study evaluated the safety and efficacy of the JETi8 peripheral thrombectomy system in treating acute deep vein thrombosis (DVT). Materials and Methods A retrospective study was conducted in 18 consecutive patients (mean age, 41 years old [range, 15-74 years old]; 5 men and 13 women). There were 21 instances of DVTs (9 iliofemoral, 10 axillosubclavian, and 2 portal), which were treated using the JETi8 thrombectomy device between November 2016 and July 2018. Thrombus was laced with recombinant tissue plasminogen activator (r-TPA) (9.3 mg, on average; range, 2–12 mg) in 17 procedures (81%) prior to thrombectomy. Technical success was defined as restoration of antegrade flow using the JETi8 with or without additional treatment of an underlying obstructive lesion. Procedural success was defined as technical success with or without the addition of overnight catheter-directed thrombolysis (CDT) Results Mean procedure time was 83 minutes (range, 30–160 minutes), and mean thrombus reduction with the JETi8 alone was 92% (range, 60%–100%). Stent placement was required in 6 procedures (29%). Technical success using the JETi8 system alone was 76% (16 of 21 procedures), whereas 5 procedures (24%) required subsequent overnight CDT in the intensive care unit. Procedural success rate was 100% (20 of 20 procedures). Mean aspirated volume was 531 mL (range, 250–1,230 mL). The only adverse event was a subsegmental pulmonary embolism. Seven patients (33%) were discharged the same day. Recurrent thrombosis was observed in 5 patients (24%), of whom 3 were successfully treated with the JETi8 system. Conclusions The JETi8 system may be a safe and effective option for thrombectomy of acute DVT.

Free flap reconstruction in acute burns has high failure rates, relating mainly to a systemic inflammatory state. The “vulnerable phase” can last for 6 weeks after burn and can cause thrombosis of the flap microcirculation with patent arterial and venous anastomoses. Revision surgery alone may be unsuccessful, but thrombolysis can lead to flap salvage. We describe a case of successful flap salvage with thrombolysis after unsuccessful revision surgery by permeable arterial and venous anastomoses in a patient in the acute burn phase suffering from microcirculatory thrombosis. Thrombolysis in these cases has not been described to date, but it could contribute to salvaging flaps by radiological intervention alone. A 23-year-old man was admitted with a 38% TBSA burn, including loss of all eyelid skin. The right eye was reconstructed in a satisfactory manner, but the left eye required urgent corneal coverage on day 32 with a dorsalis pedis fasciocutaneous free flap. The flap was hypo-perfused postoperatively, but anastomoses were found to be permeable on exploration. Angiography performed postoperatively after revision confirmed anastomotic patency, but failed to demonstrate small vessel beds within the flap. Thus, r-tPa was given at the anastomosis site and immediately the flap recovered completely. However, a total of 10 packed red blood cell transfusions were needed over the next 9 days. Thrombolysis in the context of free flap microvascular compromise may improve the overall success rates, especially in acute-phase burn patients where this etiology may be found, due to a vulnerable inflammatory period.

Abdominal aortic aneurysm (AAA) is an asymptomatic condition due to the dilation of abdominal aorta along with progressive wall degeneration, where rupture of AAA is life-threatening. Failures of AAA endovascular repair (EVAR) reflect our inadequate knowledge about the complex interaction between the aortic wall and medical devices. In this regard, we are presenting a hydrogel-based anthropomorphic mockup (AMM) to better understand the biomechanical constraints during EVAR. By adjusting the cryogenic treatments, we tailored the hydrogel to mimic the mechanical behavior of human AAA wall, thrombus and abdominal fat. A specific molding sequence and a pressurizing system were designed to reproduce the geometrical and diseased characteristics of AAA. A mechanically, anatomically and pathologically realistic AMM for AAA was developed for the first time, EVAR experiments were then performed with and without the surrounding fat. Substantial displacements of the aortic centerlines and vessel expansion were observed in the case without surrounding fat, revealing an essential framework created by the surrounding fat to account for the interactions with medical devices. In conclusion, the importance to consider surrounding tissue for the global deformation of AAA during EVAR was highlighted. Furthermore, potential use of this AMM for medical training was also suggested.

Purpose To identify quantitative dynamic contrast-enhanced (DCE)-MRI perfusion parameters indicating tumor response of hepatocellular carcinoma (HCC) to transarterial chemoembolization (TACE). Materials and methods This prospective pilot study was approved by our institutional review board; written and informed consent was obtained for each participant. Patients underwent DCE-MRI examinations before and after TACE. A variable flip-angle unenhanced 3D mDixon sequence was performed for T1 mapping. A dynamic 4D mDixon sequence was performed after contrast injection for assessing dynamic signal enhancement. Nonparametric analysis was conducted on the time-intensity curves. Parametric analysis was performed on the time-concentration curves using a dual-input single-compartment model. Treatment response according to Liver Reporting and Data System (LI-RADS) v2018 was used as the reference standard. The comparisons within groups (before vs. after treatment) and between groups (nonviable vs. equivocal or viable tumor) were performed using nonparametric bootstrap taking into account the clustering effect of lesions in patients. Results Twenty-eight patients with 52 HCCs (size: 10–104 mm) were evaluated. For nonviable tumors (n = 27), time to peak increased from 62.5 ± 18.2 s before to 83.3 ± 12.8 s after treatment (P

Objective Difficulty to recognize or canulate the right adrenal vein is the most frequent cause of adrenal venous sampling (AVS) failure. We aimed to assess multinomial regression modeling (MRM) of peripheral and left adrenal vein samplings to detect lateralization of aldosterone secretion when the right AVS is missing. Methods Simultaneous bilateral AVS samplings were performed before (basal) and after intravenous cosyntropin injection in 188 consecutive patients between December 1989 and September 2015. Different reference standards for lateralization of aldosterone secretion were defined for basal and for postcosyntropin AVS and according to lateralization index cutoffs at least 2 and at least 4. MRMs were built to detect lateralization of aldosterone secretion according to these reference standards using only peripheral and left adrenal veins samplings (without the right AVS). Detection accuracy was assessed by the area under the receiver operating characteristic (AUROC) curves and detection sensitivities were reported for specificity at least 95%. Results For basal AVS with lateralization index at least 2, AUROC were respectively 0.931 [95% confidence interval (CI) 0.894-0.968] and 0.922 (95% CI 0.882-0.962) for right and left lateralization of aldosterone secretion detection and MRM could detect respectively 65.5 and 62.7% of the right and left lateralization of aldosterone secretion. For AVS after cosyntropin with lateralization index at least 4, AUROC were respectively 0.964 (95% CI: 0.940-0.987) and 0.955 (95% CI: 0.927-0.983) for right and left lateralization of aldosterone secretion, and MRM could detect respectively 77.2 and 72.9% of the right and left lateralization of aldosterone secretion. Conclusion MRM can detect lateralization of aldosterone secretion without the right AVS in most patients and could eliminate the need for repeat AVS when right adrenal vein canulation is nonselective or impossible.

Background Coronary computed tomography angiography (CTA) allows the evaluation of coronary plaque volume and low attenuation (lipid-rich) component, for plaque vulnerability assessment. Purpose To determine the effect of iterative reconstruction (IR) on coronary plaque volume and composition. Material and Methods Consecutive patients without coronary artery disease were prospectively enrolled for 256-slice CT. Images were reconstructed with both filtered back projection (FBP) and a hybrid IR algorithm (iDose4, Philips) levels 1, 3, 5, and 7. Coronary plaques were assessed according to predefined Hounsfield unit (HU) attenuation intervals, for total plaque and HU-interval volumes. Results Fifty-three patients (mean age, 53.6 years) were included. Noise was significantly decreased and signal-to-noise ratio (SNR) / contrast-to-noise (CNR) were both significantly improved at all IR levels in comparison to FBP. Plaque characterization was performed in 41 patients for a total of 125 plaques. Total plaque volume ranged from 104.4 ± 120.7 to 107.4 ± 128.9 mm3 and low attenuation plaque component from 40.5 ± 54.7 to 43.5 ± 58.9 mm3, with no statistically significant differences between all IR levels and FBP ( P = 0.786 and P ≥ 0.078, respectively). Conclusion IR improved image quality. Total and low attenuation plaque volumes were similar using either IR or FBP.

Objective The objective of this study was to evaluate the safety and efficacy of external beam radiation (EBR) in preventing restenosis after superficial femoral artery (SFA) stenting in comparison with a control group treated with SFA stenting only. Methods In this Institutional Review Board-approved study, patients who provided written informed consent were randomly assigned to 0 Gy or 14 Gy of EBR to the stent site 24 hours after SFA stenting. The primary end point was the angiographic binary restenosis rate 2 years after stenting. Categorical and continuous end points were respectively analyzed using logistic regression models and Wilcoxon tests. End points expressed as time to event were analyzed using a log-rank test. Results The study included 155 patients, 46 women and 109 men (mean age, 66 years; range, 45-85 years). In the 0 and 14 Gy groups, binary restenosis was present, respectively, in 44% (34/77) and 68% (52/76; P = .003) 2 years after stenting. Stent thrombosis occurred in 13% (10/78) of the 0 Gy group and in 33% (25/77) of the 14 Gy group ( P = .003). Target lesion revascularization at 2 years was 26% (25/78) in the 0 Gy group and 30% (23/77) in the 14 Gy group ( P = .56). There were no significant differences in total walking distances change from baseline to 2 years (46 ± 100 and 26 ± 79 m, respectively, in the 0 Gy and 14 Gy group; P = .25). There were no procedure-related deaths and no major amputations. Conclusions A single 14 Gy dose of EBR to the SFA stenting site did not prevent in-stent restenosis.

This work combines a particle injection system with our proposed magnetic resonance navigation (MRN) sequence with the intention of validating MRN in a two-bifurcation phantom for endovascular treatment of hepatocellular carcinoma (HCC). A theoretical physical model used to calculate the most appropriate size of the magnetic drug-eluting bead (MDEB, 200 μm) aggregates was proposed. The aggregates were injected into the phantom by a dedicated particle injector while a trigger signal was automatically sent to the MRI to start MRN which consists of interleaved tracking and steering sequences. When the main branch of the phantom was parallel to B0, the aggregate distribution ratio in the (left–left, left–right, right–left and right–right divisions was obtained with results of 8, 68, 24 and 0% respectively at baseline (no MRN) and increased to 84%, 100, 84 and 92% (p

Objective: Dipole field navigation and magnetic resonance navigation exploit B0 magnetic fields and imaging gradients for targeted intra-arterial therapies by using magnetic drug-eluting beads (MDEBs). The strong magnetic strength (1.5 or 3 T) of clinical magnetic resonance imaging (MRI) scanners is the main challenge preventing the formation and controlled injection of specific-sized particle aggregates. Here, an MRI-compatible injector is proposed to solve the above problem. Methods: The injector consists of two peristaltic pumps, an optical counter, and a magnetic trap. The magnetic property of microparticles, the magnetic compatibility of different parts within the injector, and the field distribution of the MRI system were studied to determine the optimal design and setup of the injector. The performance was investigated through 30.4-emu/g biocompatible magnetic microparticles (230 ± 35 μm in diameter) corresponding to the specifications needed for trans-arterial chemoembolization in human adults. Results: The system can form aggregates containing 20 to 60 microparticles with a precision of six particles. The corresponding aggregate lengths range from 1.6 to 3.2 mm. Based on the injections of 50 MRI-visible boluses into a phantom which mimics realistic physiological conditions, 82% of the aggregates successfully reached subbranches. Conclusion and Significance: This system has the capability to operate within the strong magnetic field of a clinical 3-T MRI, to form proper particle aggregates and to automatically inject these aggregates into the MRI bore. Moreover, the versatility of the proposed injector renders it suitable for selective injections of MDEBs during MR-guided embolization procedures.

International audience; Purpose Arterial embolization has been shown to be effective and safe for the management of bleeding, especially for postpartum and pelvic traumatic bleeding. We propose to evaluate the proof of concept of feasibility and effectiveness of arterial embolization with absorbable and non-absorbable sutures in a porcine model. Materials and Methods In the acute setting (n = 1), several different arteries (mesenteric, splenic, pharyngeal, kidney) were embolized using non-absorbable sutures (NAS): Mersutures braided sutures (polyethylene terephthalate). In the chronic setting (n = 3), only lower pole renal arteries were embolized. On the right side, NAS was used, whereas on the left side embolization was realized with absorbable suture (AS): Vicryl((R)) braided suture (polyglactin 910). The chronic group was followed for 3 months. The pigs received contrast-enhanced CT the day before embolization (D-1), after the embolization (D0), at 1 month and 3 months after embolization (M1 and M3); digital subtraction angiography (DSA) was done at D0 and M3 and histological analysis at M3. Results All vascular targets were effectively embolized without any pre- or postoperative complications. Both DSAs and CTs at M3 showed a 100% recanalization rate for the AS embolization and a partial reversal rate for the NAS embolization. A renal hypotrophy in the embolized region was observed during both the M1 and M3 scans for both sutures (AS and NAS) with a clear hypotrophy for the NAS embolized kidney. Conclusion Embolization by AS and NAS (FAIR-Embo) is a feasible and effective treatment which opens up the possibility of global use of this inexpensive and widely available embolization agent.

Ultrasound noninvasive vascular elastography (NIVE) has shown its potential to measure strains of carotid arteries to predict plaque instability. When two-dimensional (2D) strain estimation is performed, either in longitudinal or cross-sectional view, only in-plane motions are considered. The motions in elevation direction (i.e. perpendicular to the imaging plane), can induce estimation artifacts affecting the accuracy of 2D NIVE. The influence of such out-of-plane motions on the performance of axial strain and axial shear strain estimations has been evaluated in this study. For this purpose, we designed a diseased carotid bifurcation phantom with a 70% stenosis and an in vitro experimental setup to simulate orthogonal out-of-plane motions of 1 mm, 2 mm and 3 mm. The Lagrangian speckle model estimator (LSME) was used to estimate axial strains and shears under pulsatile conditions. As anticipated, in vitro results showed more strain estimation artifacts with increasing magnitudes of motions in elevation. However, even with an out-of-plane motion of 2.0 mm, strain and shear estimations having inter-frame correlation coefficients higher than 0.85 were obtained. To verify findings of in vitro experiments, a clinical LSME dataset obtained from 18 participants with carotid artery stenosis was used. Deduced out-of-plane motions (ranging from 0.25 mm to 1.04 mm) of the clinical dataset were classified into three groups: small, moderate and large elevational motions. Clinical results showed that pulsatile time-varying strains and shears remained reproducible for all motion categories since inter-frame correlation coefficients were higher than 0.70, and normalized cross-correlations (NCC) between radiofrequency (RF) images were above 0.93. In summary, the performance of LSME axial strain and shear estimations appeared robust in the presence of out-of-plane motions (

Blood vessel injury during image-guided brain biopsy poses a risk of hemorrhage. Approaches that reduce this risk may minimize related patient morbidity. We present here an intraoperative imaging device that has the potential to detect the brain vasculature in situ. The device uses multiple diffuse reflectance spectra acquired in an outward-viewing geometry to detect intravascular hemoglobin, enabling the construction of an optical image in the vicinity of the biopsy needle revealing the proximity to blood vessels. This optical detection system seamlessly integrates into a commercial biopsy system without disrupting the neurosurgical clinical workflow. Using diffusive brain tissue phantoms, we show that this device can detect 0.5-mm diameter absorptive carbon rods up to [Formula: see text] from the biopsy window. We also demonstrate feasibility and practicality of the technique in a clinical environment to detect brain vasculature in an in vivo model system. In situ brain vascular detection may add a layer of safety to image-guided biopsies and minimize patient morbidity.

Multiple quantitative ultrasound (QUS) features are available from a single ultrasound radiofrequency (RF) acquisition. The objective was to test if the combination of homodyned-K (HK), elastogram, and echogenicity features could improve carotid artery plaque components characterization compared to these same features taken separately.

The purpose of this study was to evaluate ultrasound elastography and echogenicity analysis to discriminate between carotid plaques in patients with symptomatic internal carotid artery (ICA) stenosis versus patients with asymptomatic stenosis.Patients with symptomatic and asymptomatic ICA stenosis of more than 50% were recruited for the study. After both carotid arteries were scanned, plaque translation and elastography and echogenicity features were assessed. Parameters of index stenosis (i.e., symptomatic or more severe stenosis) were compared between populations. For further validation, parameters of index stenosis were also compared with those of the contralateral artery for segments with plaque. Segments without plaque on the index side were also evaluated between populations. ROC curve analyses were performed using a cross-validation method with bootstrapping to calculate sensitivity and specificity.Sixty-six patients with symptomatic (n = 26) or asymptomatic (n = 40) carotid stenoses were included. The maximum axial strain (p0.001), maximum axial shear strain magnitude (p = 0.03), and percentage of low-intensity of gray level (p = 0.01) of the index ICA were lower for patients with symptoms than for those without symptoms. In both groups, the contralateral ICA had translation and elastography and echogenicity parameters similar to those of the index ICA in patients with asymptomatic stenosis. The ROC curve for the detection of vulnerable plaques in patients with symptomatic stenosis was higher when ultrasound elastography and ultrasound echogenicity were used in combination than when each method was used alone (p0.001); a sensitivity of 71.6% and a specificity of 79.3% were obtained.This pilot study establishes the usefulness of combining elastography with echogenicity analysis to discriminate plaques in patients with symptomatic ICA stenosis versus asymptomatic stenosis.

PURPOSE To evaluate if synovial inflammation and hypervascularization are present in a dog model of knee osteoarthritis and can be detected on conventional magnetic resonance imaging (MRI), dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), contrast-enhanced magnetic resonance imaging (CE-MRI), and quantitative digital subtraction angiography (Q-DSA) imaging. MATERIALS AND METHODS Six dogs underwent MRI and angiography of both knees before and 12 weeks after right knee anterior cruciate ligament injury. Synovial vascularity was evaluated on CE-MRI, DCE-MRI, and Q-DSA by 2 independent observers. Synovial inflammation and vascularity were histologically scored independently. Cartilage lesions and osteophytes were analyzed macroscopically, and cartilage volumetry was analyzed by MRI. Vascularity and osteoarthritis markers on imaging were compared before and after osteoarthritis generation, and between the osteoarthritis model and the control knee, using linear mixed models accounting for within-dog correlation. RESULTS In all knees, baseline imaging showed no abnormalities. Control knees did not develop significant osteoarthritis changes, synovial inflammation, or hypervascularization. In osteoarthritis knees, mean synovial enhancement score on CE-MR imaging increased by 13.1 ± 0.59 (P < .0001); mean synovial inflammation variable increased from 47.33 ± 18.61 to 407.97 ± 18.61 on DCE-MR imaging (P < .0001); and area under the curve on Q-DSA increased by 1058.58 ± 199.08 (P = .0043). Synovial inflammation, hypervascularization, and osteophyte formations were present in all osteoarthritis knees. Histology scores showed strong correlation with CE-MR imaging findings (Spearman correlation coefficient [SCC] = 0.742; P = .0002) and Q-DSA findings (SCC = 0.763; P < .0001) and weak correlation with DCE-MR imaging (SCC = -0.345; P = .329). Moderate correlation was found between CE-MR imaging and DSA findings (SCC = 0.536; P = .0004). CONCLUSIONS In this early-stage knee osteoarthritis dog model, synovial inflammation and hypervascularization were found on imaging and confirmed by histology.

PURPOSE The purpose of this study was to demonstrate the feasibility of using a custom gradient sequence on an unmodified 3T magnetic resonance imaging (MRI) scanner to perform magnetic resonance navigation (MRN) by investigating the blood flow control method in vivo, reproducing the obtained rheology in a phantom mimicking porcine hepatic arterial anatomy, injecting magnetized microbead aggregates through an implantable catheter, and steering the aggregates across arterial bifurcations for selective tumor embolization. MATERIALS AND METHODS In the first phase, arterial hepatic velocity was measured using cine phase-contrast imaging in seven pigs under free-flow conditions and controlled-flow conditions, whereby a balloon catheter is used to occlude arterial flow and saline is injected at different rates. Three of the seven pigs previously underwent selective lobe embolization to simulate a chemoembolization procedure. In the second phase, the measured in vivo controlled-flow velocities were approximately reproduced in a Y-shaped vascular bifurcation phantom by injecting saline at an average rate of 0.6 mL/s with a pulsatile component. Aggregates of 200-μm magnetized particles were steered toward the right or left hepatic branch using a 20-mT/m MRN gradient. The phantom was oriented at 0°, 45°, and 90° with respect to the B0 magnetic field. The steering differences between left-right gradient and baseline were calculated using Fisher's exact test. A theoretical model of the trajectory of the aggregate within the main phantom branch taking into account gravity, magnetic force, and hydrodynamic drag was also designed, solved, and validated against the experimental results to characterize the physical limitations of the method. RESULTS At an injection rate of 0.5 mL/s, the average flow velocity decreased from 20 ± 15 to 8.4 ± 5.0 cm/s after occlusion in nonembolized pigs and from 13.6 ± 2.0 to 5.4 ± 3.0 cm/s in previously embolized pigs. The pulsatility index measured to be 1.7 ± 1.8 and 1.1 ± 0.1 for nonembolized and embolized pigs, respectively, decreased to 0.6 ± 0.4 and 0.7 ± 0.3 after occlusion. For MRN performed at each orientation, the left-right distribution of aggregates was 55%, 25%, and 75% on baseline and 100%, 100%, and 100% (P

Endovascular aneurysm repair is rapidly emerging as the primary preferred method for treating abdominal aortic aneurysm. In this image-guided interventional procedure, to obtain the roadmap and decrease contrast injections, preoperative CT images are overlaid onto live fluoroscopy images using various 2D/3D image fusion techniques. However, the structural changes due to the insertion of stiff tools degrade the fusion accuracy. To correct the mismatch and quantify the intraoperative deformations, we present a patient-specific biomechanical model of the aorto-iliac structure and its surrounding tissues. The predictive capability of the model was evaluated against intraoperative data for a group of four patients. Incorporating the perivascular tissues into the model significantly improved the results and the mean distance between the real and simulated endovascular tools was 2.99 ± 1.78 mm on the ipsilateral side and 4.59 ± 3.25 mm on the contralateral side. Moreover, the distance between the deformed iliac ostia and their corresponding landmarks on intraoperative images was 2.99 ± 2.48 mm.

Brain cancer diagnosis requires histological, molecular, and genomic tumor analyses. Since conventional imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) don’t provide molecular characterisation, tumor sampling is often achieved using a targeted needle biopsy approach. Targeting errors and cancer heterogeneity are important limitations of this technique, causing inaccurate sampling resulting in non-diagnostic or poor quality samples leading and the need for repeated biopsies, which poses an elevated patient risk because of infections and potential hemorrhages. Previously, we presented the design of an optically-guided brain biopsy needle using high wavenumber Raman spectroscopy (RS) to characterize tissue prior to sample collection with demonstrated efficacy in a live animal. Using an intraoperative probe we further demonstrated in vivo high wavenumber or fingerprint RS can distinguish cancer and normal brain tissue with >90% accuracy. Here we report on the design, development, and validation of a new intraoperative cancer detection optical needle system based on the combination of fingerprint and high wavenumber RS for highly accurate brain biopsy targeting based on molecular tissue features. This optical cancer detection device was engineered into the internal cannula of a widely used commercially available biopsy needle allowing tumor analysis prior to tissue harvesting with minimal workflow disruption. First in-human results are presented setting the stage for the clinical translation of this optical molecular imaging method for high yield and safe targeted brain biopsy.

Locating and evaluating the length and severity of a stenosis is very important for planning adequate treatment of peripheral arterial disease (PAD). Conventional ultrasound (US) examination cannot provide maps of entire lower limb arteries in 3-D. We propose a prototype 3D-US robotic system with B-mode images, which is nonionizing, noninvasive, and is able to track and reconstruct a continuous segment of the lower limb arterial tree between the groin and the knee. From an initialized cross-sectional view of the vessel, automatic tracking was conducted followed by 3D-US reconstructions evaluated using Hausdorff distance, cross-sectional area, and stenosis severity in comparison with 3-D reconstructions with computed tomography angiography (CTA). A mean Hausdorff distance of $0.97 \pm 0.46\;\text{mm}$ was found in vitro for 3D-US compared with 3D-CTA vessel representations. To evaluate the stenosis severity in vitro , 3D-US reconstructions gave errors of 3%–6% when compared with designed dimensions of the phantom, which are comparable to 3D-CTA reconstructions, with 4%–13% errors. The in vivo system’s feasibility to reconstruct a normal femoral artery segment of a volunteer was also investigated. These results encourage further ergonomic developments to increase the robot’s capacity to represent lower limb vessels in the clinical context.

To assess the sensitivity and specificity for ratios of adrenal vein cortisol level (Ca) to peripheral vein cortisol level (Cp), adrenal vein aldosterone level (Aa) to peripheral vein aldosterone level (Ap), and combined cortisol and aldosterone levels ("combined ratio") for the detection of successful adrenal vein catheterization ("selectivity") in adrenal vein sampling (AVS) without adrenocorticotropic hormone (ACTH) injection at different cutoff values.This retrospective study was approved by the institutional review board, and informed consent was waived. AVS was performed in 160 consecutive patients (49 women and 111 men; mean age, 53.6 years) between December 1989 and January 2014. Cortisol and aldosterone levels were measured in samples from the adrenal veins and left iliac vein every 5 minutes, two times before (basal) and three times after intravenous cosyntropin (ACTH 1-24) injection. Selectivity was defined by Ca/Cp or Aa/Ap ratio of at least 5 in at least one sampling after ACTH administration. Sensitivity and specificity for the detection of selective adrenal vein catheterization were calculated for basal Ca/Cp ratio, Aa/Ap ratio, and combined ratios for three cutoff values reported in the literature. The McNemar test was used to assess differences in sensitivity and specificity to detect selective adrenal vein catheterization.The sensitivity and specificity for the cutoff values of at least 3, at least 2, and at least 1.1 for the detection of AVS selectivity were respectively 50.4% and 100%, 70.8% and 100%, and 98.5% and 76.9% for Ca/Cp ratio; 61.3% and 100%, 70.8% and 100%, and 94.2% and 53.8% for Aa/Ap ratio; and 75.2% and 100%, 88.3% and 100%, and 99.3% and 46.2% for combined ratios (sensitivity at the ≥2 cutoff value: P.0001 for combined ratio vs Ca/Cp ratio and for combined ratio vs Aa/Ap ratio).Basal combined ratio has the best sensitivity for the detection of AVS selectivity at all cutoff values, and for all ratios, the cutoff value of at least 2 has the best sensitivity for 100% specificity.

Here we address the automatic segmentation of endovascular devices used in the endovascular repair (EVAR) of abdominal aortic aneurysms (AAA) that deform vascular tissues. Using this approach, the vascular structure is automatically reshaped solving the issue of misregistration observed on 2D/3D image fusion for EVAR guidance. The endovascular devices we considered are the graduated pigtail catheter (PC) used for contrast injection and the stent-graft delivery device (DD). The segmentation of the DD was enhanced using an asymmetric Frangi filter. The segmented geometries were then analysed using their specific features to remove artefacts. The radiopaque markers of the PC were enhanced using a fusion of Hessian and newly introduced gradient norm shift filters. Extensive experiments were performed using a database of images taken during 28 AAA-EVAR interventions. This dataset was divided into two parts: the first half was used to optimize parameters and the second to compile performances using optimal values obtained. The radiopaque markers of the PC were detected with a sensitivity of 88.3% and a positive predictive value (PPV) of 96%. The PC can therefore be positioned with a majority of its markers localized while the artefacts were all located inside the vessel lumen. The major parts of the DD, the dilatator tip and the pusher surfaces, were detected accurately with a sensitivity of 85.9% and a PPV of 88.7%. The less visible part of the DD, the stent enclosed within the sheath, was segmented with a sensitivity of 63.4% because the radiopacity of this region is low and uneven. The centreline of the DD in this stent region was alternatively traced within a 0.74 mm mean error. The automatic segmentation of endovascular devices during EVAR is feasible and accurate; it could be useful to perform elastic registration of the vascular lumen during endovascular repair.

The purpose of this study was to determine the incidence of nephrogenic systemic fibrosis (NSF) in patients with chronic kidney disease (CKD) and moderate-to-severe impairment of kidney function who had not previously been exposed to gadolinium-based contrast agents (GBCAs) or referred to undergo contrast-enhanced MRI with gadobenate dimeglumine or gadoteridol.Two multicenter prospective cohort studies evaluated the incidence of unconfounded NSF in patients with stage 3 CKD (estimated glomerular filtration rate [eGFR] in cohort 1, 30-59 mL/min/1.73 m(2)) or stage 4 or 5 CKD (eGFR in cohort 2,30 mL/min/1.73 m(2)) after injection of gadobenate dimeglumine (study A) or gadoteridol (study B). A third study (study C) determined the incidence of NSF in patients with stage 4 or 5 CKD who had not received a GBCA in the 10 years before enrollment. Monitoring for signs and symptoms suggestive of NSF was performed via telephone at 1, 3, 6, and 18 months, with clinic visits occurring at 1 and 2 years.For studies A and B, the populations evaluated for NSF comprised 363 and 171 patients, respectively, with 318 and 159 patients in cohort 1 of each study, respectively, and with 45 and 12 patients in cohort 2, respectively. No signs or symptoms of NSF were reported or detected during the 2 years of patient monitoring. Likewise, no cases of NSF were reported for any of the 405 subjects enrolled in study C.To our knowledge, and consistent with reports in the literature, no association of gadobenate dimeglumine or gadoteridol with unconfounded cases of NSF has yet been established. Study data confirm that both gadoteridol and gadobenate dimeglumine properly belong to the class of GBCAs considered to be associated with the lowest risk of NSF.