Myocardial blood flows and reserves on solid state camera: Correlations with coronary history and cardiovascular risk factors.

OBJECTIVES: Study designed to test association between stress-induced myocardial blood flow (sMBF), resting MBF (rMBF), and MBF reserve (MFR) and coronary artery disease (CAD) in a population of CAD and non-coronary patients. Secondary objectives were to confront visual analysis and dynamic analysis and to explore potential association between MBF and several cardiovascular risk factors METHODS: A total of 155 patients who underwent dynamic myocardial perfusion imaging on a CZT camera were included. sMBF, rMBF, and MFR were evaluated, and cardiovascular risk was assessed. RESULTS: Significantly lower total sMBF and MFR were observed in CAD patient vs non-CAD patient. In comparison with visual analysis, lower sMBF were found in pathologic territory, lower rMBF in necrotic territory and lower MFR in necrotic ones. A significant correlation between total sMBF, rMBF and diabetes was found. CONCLUSION: sMBF and MFR as assessed on CZT gamma-cameras can be used to determine the coronary state. Low total sMBF might be an independent risk factor of coronaropathy. An inverse correlation was suggested between total sMBF and rMBF with diabetes.

Prognostic utility of pre-transplantation [18 F] fluorodeoxyglucose positron emission tomography/computed tomography in patients with diffuse large B-cell lymphoma who underwent rituximab, dexamethasone, high-dose cytarabine, carboplatin salvage chemotherapy.

We analysed the outcomes of 62 patients with refractory/relapsed diffuse large B-cell lymphoma (rrDLBCL) who had pre-transplantation fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) after R-DHAC (rituximab, dexamethasone, high-dose cytarabine, carboplatin) salvage chemotherapy, and were evaluated using Deauville criteria and total lesion glycolysis (TLG). A positive pre-transplantation PET/CT with Deauville score of 5 was associated with shorter progression-free survival (PFS) (P = 0·01), while a Deauville score of 4 was not predictive of outcome. Only pre-transplant TLG was significantly associated with both PFS (P = 0·005) and overall survival (P = 0·03). TLG deserves to be further investigated in prospective studies.

Prospective comparison of 18-FDG PET/CT and whole-body diffusion-weighted MRI in the assessment of multiple myeloma.

Magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18FDG 18F-FDG PET-CT) are standard procedures for staging multiple myeloma (MM). Diffusion-weighted sequences applied to whole-body MRI (WB-DWI) improve its sensitivity. We compared the number of MM bone focal lesions (FLs) detected by 18F-FDG PET-CT and WB-DWI and evaluated the diagnostic performance of 18F-FDG PET-CT for diffuse infiltration. Thirty newly diagnosed MM patients prospectively underwent 18F-FDG PET-CT and WB-DWI. The criteria for skeletal region positivity were ≥ 1 focal bone lesions (FLs) and/or diffuse disease. MRI with the MY-RADS criteria was used as a reference standard for the diagnosis of diffuse infiltration. 18F-FDG PET-CT and WB-DWI were both interpreted as positive in 28/30 patients with an agreement of 1.00 (95% CI 0.77-1.00) between the two methods. The mean numbers of FLs were 16.7 detected by 18F-FDG PET-CT and 23.9 detected by WB-DWI (P = 0.028). WB-DWI detected more FLs in the skull (P = 0.001) and spine (P = 0.006). Agreement assessed using the prevalence and bias-corrected kappa index was moderate (0.40-0.60) for the spine, sternum-ribs and upper limbs and substantial (0.60-0.80) for the pelvis and lower limbs. As regards the diagnosis of diffuse bone marrow infiltration, the sensitivity, specificity and accuracy of 18F-FDG PET-CT were 0.75, 0.79 and 0.77, respectively. Although WB-DWI detected more FLs than did 18F-FDG PET-CT, there was no difference in the detection of bone disease on a per-patient basis. 18F-FDG PET-CT showed high performance, including for evaluation of diffuse infiltration.

Comparison of Two Percutaneous Atrial Septal Defect Occluders for Device Healing and Nickel Release in a Chronic Porcine Model.

AIMS: To investigate the healing process and nickel release of the Hyperion occluder (Comed BV, Netherlands), as compared to the Amplatzer septal occluder (ASO) (St. Jude Medical Inc., St. Paul, MN, USA) in a chronic swine model. BACKGROUND: Some long-term complications occurring after percutaneous atrial septal defect (ASD) closure may be partially associated with an inappropriate healing of the device and increased nickel release. There is no direct comparative study of different occluders for healing and nickel release. METHODS: After percutaneous ASD creation, 12 pigs were implanted with 15 mm Hyperion (n = 6) and 15 mm ASO (n = 6) devices. After 1 month (n = 3 for each device) and 3 months (n = 3 for each device) of follow-up, device explantation was performed and healing was assessed using histopathological workup. Systemic and tissular nickel release was performed. RESULTS: Implantation was successful in 100% without complications. Device coverage was observed as early as 1 month after implantation and was almost complete after 3 months. A granulation tissue with a predominantly mononuclear inflammatory reaction was observed in contact with nitinol wires while an inflammatory reaction was seen in contact with textile fibers. We found no statistically significant difference between the 2 devices whether for histological grading scores or systemic nickel release, regardless to follow-up duration. CONCLUSIONS: In this preclinical study, we demonstrated that Amplatzer septal occluder and Hyperion occluder were not significantly different for device healing and nickel release processes.

In vitro Evidence of Improved Antimicrobial Efficacy of Silver and Triclosan Containing Vascular Grafts Compared with Rifampicin Soaked Grafts.

OBJECTIVES: The aim was to compare the antimicrobial efficacy of four different grafts: a standard graft (Intergard, IG), an IG graft soaked in rifampicin (IGrif), a silver impregnated graft (Intergard Silver, IGS), and a silver + triclosan impregnated graft (Intergard Synergy, IGSy). METHODS: This was a seven day in vitro study. The IG, IGrif, IGS, and IGSy grafts were each contaminated separately with the following microorganisms: Staphylococcus epidermidis, Methicillin resistant Staphylococcus aureus (MRSA), Escherichia coli, and Candida albicans from both clinical and American Type Culture Collection (ATCC) origins. The in vitro antimicrobial efficacy was evaluated by time to kill assays at T0, T24h, T48h, T72h, and T168h. Bactericidal activity was defined as >3 log10 reduction factor (logRF). Additionally, Rifampicin, triclosan and silver resistance development were screened. RESULTS: As anticipated for the non-antimicrobial IG, all microorganism strains proliferated. The IGSy and the IGS showed a seven day bactericidal efficacy (>3 logRF) for all tested microorganisms. This efficacy was confirmed at all time points for IGSy only, demonstrating faster bactericidal efficacy than IGS. The IGrif demonstrated a seven day bactericidal efficacy against the ATCC MRSA only, while showing no activity against C. albicans and ATCC E. coli. Regarding ATCC S. epidermidis, clinical MRSA and clinical E. coli, IGrif, although bactericidal at earlier time points, lost its antimicrobial efficacy at seven days leading to the emergence of rifampicin resistant mutants in four of six, two of six, and two of six assays, respectively. Mutant strains were also detected in ATCC MRSA in one of six assays. No triclosan or silver resistance has emerged at T7days. CONCLUSION: For all microorganisms tested, the Synergy graft combining silver with triclosan demonstrated a more sustainable and efficient seven day antimicrobial activity than the rifampicin soaked graft. The emergence of rifampicin resistant mutants suggests preference for a Synergy graft over a graft soaked in rifampicin, to prevent or treat an infection when a biological solution is not feasible.

Retrospective Study Comparing WBC scan and 18F-FDG PET/CT in Patients with Suspected Prosthetic Vascular Graft Infection.

OBJECTIVES: Prosthetic vascular graft infections (PVGIs) are associated with high mortality rates. To improve treatment outcome, an early and definite diagnosis is critical, and current diagnostic criteria are often insufficient. The accuracy of 2-deoxy-2-[fluorine-18]-fluoro-d-glucose positron emission tomography integrated with computed tomography (18F-FDG PET/CT) and white blood cell (WBC) scan for the diagnosis of PVGI were compared. METHODS: A retrospective single centre study was conducted on patients undergoing WBC scan and 18F-FDG PET/CT for a suspected PVGI between April 2013 and June 2016 at the Bordeaux University Hospital, France. The diagnostic value of both imaging tests was assessed for all grafts, using receiver operating characteristic (ROC) curve analysis. Images were independently interpreted by two nuclear medicine physicians blinded to the patients' clinical and other imaging data. RESULTS: Thirty-nine patients were included, of whom 15 had PVGI. Antibiotic treatment was started before nuclear imaging for 16 patients, including nine patients with a PVGI. The 96 grafts of these patients were analysed, and 19 were infected. The diagnostic value of the WBC scan was significantly higher than 18F-FDG PET/CT (ROC AUC = 0.902, 95% CI 0.824-0.980, and 0.759, CI 95% (0.659-0.858), respectively, p = .0071). Interobserver agreement was good for 18F-FDG PET/CT and excellent for WBC scan (kappa value of 0.76, 95% CI 0.62-0.9, and 0.97, 95% CI 0.92-1, respectively). Only one patient had a false negative 18F-FDG PET/CT result under antibiotic therapy. CONCLUSION: The WBC scan has a better diagnostic value than 18F-FDG PET/CT for PVGI diagnosis.

Prospective, randomized, controlled, open-label study to compare efficacy of a mineral-rich solution vs normal saline after complete ethmoidectomy.

PURPOSES: The purpose of this study was to compare the efficacy of a mineral-rich solution vs normal saline solution (0.9% NaCl) following endoscopic complete bilateral ethmoidectomy. METHODS: This was a prospective, multicenter, randomized, controlled, open-label trial in subjects suffering from steroid-resistant sinonasal polyposis. Adults performed 4 nasal irrigations of mineral or saline solutions daily for 28 days. Evaluations included subject-reported RHINO quality of life (QoL) and NOSE scores, tolerability, and satisfaction, the Lund-Kennedy endoscopic score and assessments of crusting, secretions and mucociliary clearance (rhinoscintigraphy). RESULTS: A total of 189 subjects were randomized. Clinically relevant improvements (> 20 points) in RhinoQOL and NOSE scores were measured in both groups without any significant inter-group difference. Among the subjects with impaired RhinoQOL at pre-inclusion, the change in Impact-RhinoQOL score was significantly superior in mineral-rich vs saline solution at day 21 (p = 0.028) and day 28 (p = 0.027). The Lund-Kennedy score continuously improved in both groups earlier with the mineral-rich solution. Crusts were significantly fewer in number and less severe/obstructive in patients receiving mineral-rich vs saline solution at day 7 (p = 0.026) and day 14 (p = 0.016). Furthermore, secretions disappeared significantly more quickly and were less thick/purulent with mineral-rich solution at day 14 (p = 0.002) and day 21 (p = 0.043). Less epistaxis was reported in the mineral vs saline solution (p = 0.008 at day 21). CONCLUSIONS: Our findings indicate that the composition of a nasal irrigation solution influences endoscopic scores and QoL after sinus surgery for patients over 60, those with an initially poor QoL and higher symptom score, and smokers.

Assessment of vertebral microarchitecture in overt and mild Cushing's syndrome using trabecular bone score.

OBJECTIVE: Osteoporotic fractures associated with Cushing's syndrome (CS) may occur despite normal bone mineral density (BMD). Few studies have described alterations in vertebral microarchitecture in glucocorticoid-treated patients and during CS. Trabecular bone score (TBS) estimates trabecular microarchitecture from dual-energy X-ray absorptiometry acquisitions. Our aim was to compare vertebral BMD and TBS in patients with overt CS and mild autonomous cortisol secretion (MACE), and following cure of overt CS. SETTING: University Hospital. DESIGN: Monocentric retrospective cross-sectional and longitudinal studies of consecutive patients. PATIENTS: A total of 110 patients were studied: 53 patients had CS (35, 11 and 7 patients with Cushing's disease, bilateral macronodular adrenal hyperplasia and ectopic ACTH secretion respectively); 39 patients had MACE (10 patients with a late post-operative recurrence of Cushing's disease and 29 patients with adrenal incidentalomas); 18 patients with non-secreting adrenal incidentalomas. 14 patients with overt CS were followed for up to 2 years after cure. RESULTS: Vertebral osteoporosis at BMD and degraded microarchitecture at TBS were found in 24% and 43% of patients with CS, respectively (P < .03). As compared to patients with nonsecreting incidentalomas, patients with MACE had significantly decreased TBS (P < .04) but not BMD. Overt fragility fractures tended to be associated with low TBS (P = .07) but not with low BMD. TBS, but not BMD values, decreased with the intensity of hypercortisolism independently of its aetiology (P < .01). Following remission of CS, TBS improved more markedly and rapidly than BMD (10% vs 3%, respectively; P < .02). CONCLUSION: Trabecular bone score may be a promising, noninvasive, widely available and inexpensive complementary tool for the routine assessment of the impact of CS and MACE on bone in clinical practice.

Hodgkin lymphoma: a negative interim-PET cannot circumvent the need for end-of-treatment-PET evaluation.

We examined the outcome of a cohort of patients with Hodgkin lymphoma (HL) in order to assess if fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) at the end of treatment (end-PET) can be omitted when the interim PET (int-PET) is negative. Seventy-six ABVD(adriamycin, bleomycin, vinblastine, dacarbazine)-treated patients were retrospectively included. No change in treatment was made on the basis of int-PET results. Suspicious foci on end-PET received biopsy confirmation whenever possible. Median follow-up was 58·9 months. Uptake on int-PET higher than liver (scores 4-5) was rated positive according to the Lugano classification, while a positive end-PET corresponded to scores 3, 4 and 5. Fifteen patients had treatment failure. Sensitivity, specificity, positive predictive value (PPV), negative predictive value and accuracy of int-PET were 46·7%, 85·2%, 43·8%, 86·7% and 77·6%, respectively. For end-PET the figures were: 80%, 93·4%, 75%, 95% and 90·8%. Eight patients with negative int-PET had treatment failure; six of them were identified as non-responders with end-PET. The 5-year progression-free survival (PFS) was 87% for patients with negative int-PET versus 56% with positive int-PET. The 5-year PFS was 96% with negative end-PET versus 23% with positive end-PET. The prognostic information from int-PET as regards PFS (log-rank test P = 0·0048) was lower than that provided by end-PET (P < 0·0001). Int-PET predicted only half of the failures. When used in clinical routine, a negative int-PET study cannot obviate the need for end-PET examination.

Early prosthetic aortic valve infection identified with the use of positron emission tomography in a patient with lead endocarditis.

BACKGROUND: 18-Fluorodeoxyglucose positron emission tomography/computerized tomography (FDG PET/CT) scanning has recently been proposed as a diagnostic tool for lead endocarditis (LE). OBJECTIVE: FDG PET/CT might be also useful to localize associated septic emboli in patients with LE. CASE PRESENTATION: We report an interesting case of a LE patient with a prosthetic aortic valve in whom a trans-esophageal echocardiogram did not show associated aortic endocarditis. FDG PET/CT revealed prosthetic aortic valve infection. A second TEE performed 2 weeks after identified aortic vegetation. A longer duration of antimicrobial therapy with serial follow-up echocardiography was initiated. There was also increased uptake in the sigmoid colon, corresponding to focal polyps resected during a colonoscopy. CONCLUSION: FDG PET/CT scanning seems to be highly sensitive for prosthetic aortic valve endocarditis diagnosis. This promising diagnostic tool may be beneficial in LE patients, by identifying septic emboli and potential sites of pathogen entry.

High performances of (18)F-fluorodeoxyglucose PET-CT in cardiac implantable device infections: A study of 40 patients.

BACKGROUND: Cardiovascular implantable electronic devices (CIED) infections are life-threatening complications. The diagnosis can be difficult to establish. Our purpose is to evaluate the diagnostic value of (18)F-FDG PET. METHODS: Forty patients who received work-up for suspected CIED infection were retrospectively included (group 1) and compared with 40 controls (group 2); CIED patients were referred for oncologic PET. PET-CT data were blindly assessed. Interpretation was based on visual analysis of both attenuation-corrected and non-corrected images and a semi-quantitative analysis was performed. The gold standard was bacteriological data of explanted devices or clinical follow-up for at least 1 year. RESULTS: Infection was present in 18 out of 40 patients of group 1. Sensitivity, specificity, positive predictive value, and negative predictive value of PET-CT were 83%, 95%, 94%, and 88%, respectively. Accuracy was 90%. PET-CT revealed the presence of additional pathological hypermetabolic foci in 28% of cases. PET-CT was negative at implanted devices in all patients of group 2. CONCLUSION: (18)F-FDG PET-CT is helpful in the work-up of suspected CIED infections. It is a potential tool to make the accurate diagnosis of CIED infection and to assess the extent of infection. The promising results in this indication need to be validated in a prospective multicenter study.

18F-FDG PET-CT in suspected prosthetic vascular graft infection.

BACKGROUND: Diagnosis of prosthetic vascular graft infections is a clinical challenge, and surgical therapy is associated with comorbidity. Therefore, accurate diagnostic methods are required for their optimal management. METHODS: A 61-year-old-patient presented with erysipelas of the right lower limb 7 months after receiving a hybrid femoropopliteal bypass composed of a saphenous vein distally and external supported polytetrafluoroethylene proximally. He had been first treated for suspicious of septic arterial thrombosis or false aneurysm with antibiotics. A computed tomography (CT) angiogram was performed to detect any potential infection of the bypass and to explore erysipelas. It revealed a subcutaneous infiltration and an infiltration of the right groin but no anastomotic pseudoaneurysm or thrombosis of the bypass. The 2-[18F]-fluoro-2-desoxy-d-glucose positron emission tomography (18F-FDG PET) evidenced a significant uptake of cutaneous and subcutaneous tissue but no uptake on the vascular prosthetic graft. Therefore, the bypass was considered as noninfected and antibiotics were continued for 3 months. A physical examination on antibiotic cessation revealed a nonerythematous thigh with a C-reactive protein level significantly decreased to 36 mg/L and a normal white blood cell count. A PET scan confirmed this clinical improvement as attested by a dramatically decreased uptake of cutaneous and subcutaneous tissues and still no uptake of the graft. CONCLUSIONS: In conclusion, this case highlights the role that 18F-FDG PET-CT may play in excluding suspected prosthetic graft infection, thanks to its high sensitivity and in avoiding needless revision surgery with subsequent comorbidities.

Should white blood cell scan be replaced by (18)F-FDG PET-CT in the diagnosis of prosthetic vascular graft infection?

Diagnosis of prosthetic vascular graft infection (PVGI) is a clinical challenge requiring accurate diagnostic methods for their optimal management. A 65-year-old patient with suspected PVGI was explored by fluorodeoxyglucose positron emission tomography combined with computed tomography ((18)F-FDG PET-CT) for pretreatment staging. Standard imaging was unrevealing but PET images showed multiple foci with increased uptake suggesting prosthetic infection. While routine results from the diagnostic laboratory were negative, prosthesis sonication before standard culture revealed the same bacterium as a culture of preoperative lymphocele aspiration. (18)F-FDG PET-CT and preliminary sonication of the prosthetic graft could be very helpful in the diagnosis of PVGI especially for highlighting biofilm bacteria.

Role of hemodynamic forces in the ex vivo arterialization of human saphenous veins.

BACKGROUND: Human saphenous vein grafts are one of the salvage bypass conduits when endovascular procedures are not feasible or fail. Understanding the remodeling process that venous grafts undergo during exposure to arterial conditions is crucial to improve their patency, which is often compromised by intimal hyperplasia. The precise role of hemodynamic forces such as shear stress and arterial pressure in this remodeling is not fully characterized. The aim of this study was to determine the involvement of arterial shear stress and pressure on vein wall remodeling and to unravel the underlying molecular mechanisms. METHODS: An ex vivo vein support system was modified for chronic (up to 1 week), pulsatile perfusion of human saphenous veins under controlled conditions that permitted the separate control of arterial shear stress and different arterial pressure (7 mm Hg or 70 mm Hg). RESULTS: Veins perfused for 7 days under high pressure (70 mm Hg) underwent significant development of a neointima compared with veins exposed to low pressure (7 mm Hg). These structural changes were associated with altered expression of several molecular markers. Exposure to an arterial shear stress under low pressure increased the expression of matrix metalloproteinase (MMP)-2 and MMP-9 and tissue inhibitor of metalloproteinase (TIMP)-1 at the transcript, protein, and activity levels. This increase was enhanced by high pressure, which also increased TIMP-2 protein expression despite decreased levels of the cognate transcript. In contrast, the expression of plasminogen activator inhibitor-1 increased with shear stress but was not modified by pressure. Levels of the venous marker Eph-B4 were decreased under arterial shear stress, and levels of the arterial marker Ephrin-B2 were downregulated under high-pressure conditions. CONCLUSIONS: This model is a valuable tool to identify the role of hemodynamic forces and to decipher the molecular mechanisms leading to failure of human saphenous vein grafts. Under ex vivo conditions, arterial perfusion is sufficient to activate the remodeling of human veins, a change that is associated with the loss of specific vein markers. Elevation of pressure generates intimal hyperplasia, even though veins do not acquire arterial markers. CLINICAL RELEVANCE: The pathological remodeling of the venous wall, which leads to stenosis and ultimately graft failure, is the main limiting factor of human saphenous vein graft bypass. This remodeling is due to the hemodynamic adaptation of the vein to the arterial environment and cannot be prevented by conventional therapy. To develop a more targeted therapy, a better understanding of the molecular mechanisms involved in intimal hyperplasia is essential, which requires the development of ex vivo models of chronic perfusion of human veins.

3D-Printed Osteoinductive Polymeric Scaffolds with Optimized Architecture to Repair a Sheep Metatarsal Critical-Size Bone Defect.

The reconstruction of critical-size bone defects in long bones remains a challenge for clinicians. A new osteoinductive medical device is developed here for long bone repair by combining a 3D-printed architectured cylindrical scaffold made of clinical-grade polylactic acid (PLA) with a polyelectrolyte film coating delivering the osteogenic bone morphogenetic protein 2 (BMP-2). This film-coated scaffold is used to repair a sheep metatarsal 25-mm long critical-size bone defect. In vitro and in vivo biocompatibility of the film-coated PLA material is proved according to ISO standards. Scaffold geometry is found to influence BMP-2 incorporation. Bone regeneration is followed using X-ray scans, µCT scans, and histology. It is shown that scaffold internal geometry, notably pore shape, influenced bone regeneration, which is homogenous longitudinally. Scaffolds with cubic pores of ≈870 µm and a low BMP-2 dose of ≈120 µg cm-3 induce the best bone regeneration without any adverse effects. The visual score given by clinicians during animal follow-up is found to be an easy way to predict bone regeneration. This work opens perspectives for a clinical application in personalized bone regeneration.

Cytocompatibility / Antibacterial Activity Trade-off for Knittable Wet-Spun Chitosan Monofilaments Functionalized by the In Situ Incorporation of Cu2+ and Zn2.

The wet spinning of cytocompatible, bioresorbable, and knittable chitosan (CTS) monofilaments would be advantageous for a variety of surgical applications. The complexation capacity of chitosan with Cu2+ or Zn2+ can be leveraged to enhance its antibacterial activity, but not at the expense of cytocompatibility. In this work, a wet-spinning process was adapted for the in situ incorporation of Cu2+ or Zn2+ with chitosan dopes to produce monofilaments at different drawing ratios (τtot) with various cation/glucosamine molar ratios, evaluated in the fibers (rCu,f and rZn,f). Cytocompatibility and antibacterial activity of wet-spun monofilaments were, respectively, quantified by in vitro live-dead assays on balb 3T3 and by different evaluations of the proliferation inhibition of Staphylococcus epidermidis (Gram+) and Escherichia coli (Gram-). Knittability was tested by a specific tensile test using a knitting needle and evaluated with an industrial knitting machine. It was found that rCu,f = 0.01 and rZn,f = 0.03 significantly increase the antibacterial activity without compromising cytocompatibility. Wet spinning with τtot = 1.6 allowed the production of knittable CTS-Cu monofilaments, as confirmed by knitting assays under industrial conditions.

Comparison of MRI-based response criteria and radiomics for the prediction of early response to transarterial radioembolization in patients with hepatocellular carcinoma.

PURPOSE: The purpose of this study was to evaluate the capabilities of radiomics using magnetic resonance imaging (MRI) data in the assessment of treatment response to 90yttrium transarterial radioembolization (TARE) in patients with locally advanced hepatocellular carcinoma (HCC) by comparison with predictions based on European Association for the Study of the Liver (EASL) criteria. PATIENTS AND METHODS: Twenty-two patients with HCC (19 men, 3 women; mean age: 66.7 ± 9.8 [SD]; age range: 37-82 years) who underwent contrast-enhanced MRI 4 ± 1 weeks before and 4 ± 4 weeks after TARE, were enrolled in this retrospective study. Regions of interest were placed manually along the contours of the treated tumor on each axial slice of arterial and portal phase images using the ITK-SNAP post-processing software. For each MRI, the Pyradiomics Python package was used to extract 107 radiomics features on both arterial and portal phases, and resulting delta-features were computed. The Mann-Whitney U test with Bonferroni correction was used to select statistically different features between responders and non-responders (i.e., those with progressive or stable disease) at 6-month follow-up, according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST). Finally, for each selected feature, univariable logistic regression with leave-one-out cross validation procedure was used to perform receiver operating characteristic (ROC) curve analysis and compare radiomics parameters with MRI variables. RESULTS: According to mRECIST, 14 patients (14/22; 64%) were non-responders and 8 (8/22; 36%) were responders. Four radiomics parameters (long run emphasis, minor axis length, surface area, and gray level non-uniformity on arterial phase images) were the only predictors of early response. ROC curve analysis showed that long run emphasis was the best parameter for predicting early response, with 100% sensitivity (95% CI: 68-100) and 100% specificity (95% CI: 78-100). EASL morphologic criteria yielded 75% sensitivity (95% CI: 41-96%) and 93% specificity (95% CI: 69-100%). CONCLUSION: Radiomics allows identify marked differences between responders and non-responders, and could aid in the prediction of early treatment response following TARE in patients with HCC.

[Stem cells for osteoarticular and vascular tissue engineering]. / Les cellules souches en ingénierie des tissus ostéoarticulaires et vasculaires.

Tissue damages or loss of organs often result in structural and metabolic changes that can cause serious complications. The therapeutic objective of tissue engineering (TE) is to recreate, regenerate or restore function of damaged tissue. TE is based on the coalescence of three components: a scaffold or matrix from natural or synthetic origin biodegradable or not, reparative cells and signals (hypoxia, mechanical stress, morphogens…). Articular cartilage, bone and blood vessels are tissues for which TE has progressed significantly, from basic research to clinical trials. If biomaterials must exhibit different properties depending on the tissue to regenerate, the cellular component of TE is mostly represented by stem cells notably adult mesenchymal stem cells harvested from bone marrow or adipose tissue. In recent years, progress has been made in our understanding of the biological mechanisms that govern stem cell differentiation and in the development of materials with controlled physicochemical and biological properties. However, many technological barriers and regulations concerns have to be overcome before tissue engineering enters into the therapeutic arsenal of regenerative medicine. This review aims at highlighting the progress in the use of stem cells for engineering osteoarticular and vascular tissues.

Prospective Comparison of 18-FDG PET/CT and Whole-Body MRI with Diffusion-Weighted Imaging in the Evaluation of Treatment Response of Multiple Myeloma Patients Eligible for Autologous Stem Cell Transplant.

To compare the prognostic values of 18-FDG PET/CT (FDG-PET) and Whole-Body MRI with Diffusion-Weighted Imaging (WB-DW-MRI) in the evaluation of treatment response of Multiple Myeloma (MM) patients eligible for ASCT. Thirty patients with newly diagnosed MM prospectively underwent FDG-PET and WB-DW-MRI at baseline, after induction chemotherapy and after ASCT. Response on WB-DW-MRI was evaluated with the MY-RADS criteria. FDG-PET was considered positive if residual uptake was superior to liver uptake. Imaging results were not used for treatment modification. The impact of imaging results on PFS was analyzed. After a median follow-up of 32 months, 10 patients relapsed. With WB-DW-MRI, post-induction examination was positive in 3/25 and post-ASCT examination was positive in 3/27 patients. However, neither study showed prognostic impact on PFS. FDG-PET was positive in 5/22 post-induction and 3/26 patients post-ASCT, respectively. Positivity of FDG-PET, post-induction or post-ASCT, was associated with a shorter PFS (post-induction: median PFS 19 months vs. not reached, log-rank p = 0.0089; post-ASCT: median PFS 18 months vs. not reached, log-rank p = 0.0005). Preliminary results from this small, single-center, prospective study show that, whether performed post-induction or post-ASCT, FDG-PET has a higher prognostic value than WB-DW-MRI for treatment response evaluation of newly diagnosed MM.