Lipid Nanocapsules Loaded with Rhenium-188 Reduce Tumor Progression in a Rat Hepatocellular Carcinoma Model

International audienceBACKGROUND: Due to their nanometric scale (50 nm) along with their biomimetic properties, lipid nanocapsules loaded with Rhenium-188 (LNC(188)Re-SSS) constitute a promising radiopharmaceutical carrier for hepatocellular carcinoma treatment as its size may improve tumor penetration in comparison with microspheres devices. This study was conducted to confirm the feasibility and to assess the efficacy of internal radiation with LNC(188)Re-SSS in a chemically induced hepatocellular carcinoma rat model. METHODOLOGY/PRINCIPAL FINDINGS: Animals were treated with an injection of LNC(188)Re-SSS (80 MBq or 120 MBq). The treated animals (80 MBq, n = 12; 120 MBq, n = 11) were compared with sham (n = 12), blank LNC (n = 7) and (188)Re-perrhenate (n = 4) animals. The evaluation criteria included rat survival, tumor volume assessment, and vascular endothelial growth factor quantification. Following treatment with LNC(188)Re-SSS (80 MBq) therapeutic efficiency was demonstrated by an increase in the median survival from 54 to 107% compared with control groups with up to 7 long-term survivors in the LNC(188)Re-SSS group. Decreased vascular endothelial growth factor expression in the treated rats could indicate alterations in the angiogenesis process. CONCLUSIONS/SIGNIFICANCE: Overall, these results demonstrate that internal radiation with LNC(188)Re-SSS is a promising new strategy for hepatocellular carcinoma treatment

Diagnose du lac Sommet, Zec Bas Saint-Laurent

L’omble de fontaine (Salvelinus fontinalis) est un salmonidé très recherché dans le domaine de la pêche sportive au Québec. Dans l’optique de déterminer l’état de la population du lac Sommet, un lac peu profond de la ZEC Bas-Saint-Laurent, une diagnose fut réalisée le 31 août et le 1er septembre. Ainsi, les paramètres physicochimiques et la bathymétrie du lac ont été mesurés. De plus, une pêche expérimentale fut exécutée pour déterminer la diversité et l’abondance des espèces du lac. Le potentiel de frai fut évalué au niveau du tributaire, de l’émissaire et sur les rives du lac. Cette étude démontre que l’influence de certains paramètres physico-chimiques, la compétition interspécifique et la condition de l’habitat ont une forte répercussion sur la population d’ombles de fontaine de ce lac. Le problème de recrutement est omniprésent dans le lac Sommet

Comment quantifier la stéatose hépatique ?

International audienceThe frequency of hepatic steatosis in the population and its potential complications require knowing how to diagnose and quantify this lesion in clinical practice. Ultrasound allows semi-quantification based on the liver/kidney signal ratio. The CT scanner has a marginal rule, mainly before surgery of resection and before transplantation. MRI is the technique of choice for quantification, using simple multi-echo techniques and manufacturer or free softwares like MRQuantif. The quantification of steatosis in MRI should always be associated with iron quantification to avoid errors. The discovery of steatosis must systematically lead to the search for hepatic fibrosis, at best at the same time using ultrasonore elastometry. Incidental finding of steatosis must be semi-quantified and noted in the report. The indications to look after hepatic steatosis are the existence of liver biological abnormalities, obesity, type 2 diabetes, metabolic syndrome or the existence of cardiovascular risks. In this situation, ultrasound technic is recommended for the evaluation of steatosis. When accurate quantification of steatosis is required, the currently recommended tool is MRI with the multi-echo technique.La fréquence de la stéatose hépatique et ses complications potentielles imposent de savoir diagnostiquer et quantifier cette lésion au quotidien. L’échographie permet une semi-quantification en se basant sur le rapport de signal foie/rein. Le scanner à une place marginale principalement avant chirurgie et avant transplantation dans les bilans des donneurs potentiels. L’IRM est l’examen de quantification, par le biais des techniques simples multiéchos et les logiciels constructeurs ou publics type MRQuantif. La quantification de la stéatose en IRM doit toujours être associée à celle du fer pour éviter les erreurs de quantification. La découverte d’une stéatose doit entraîner systématiquement la recherche d’une fibrose hépatique, au mieux dans le même temps en utilisant les outils d’élastométrie ultrasonore. Outre, la découverte fortuite qui doit être semi-quantifiée et notée dans le compte rendu, les indications de diagnostic de stéatose hépatique sont l’existence de perturbations du bilan biologique hépatique, d’une obésité, d’un diabète de type 2, d’un syndrome métabolique ou de risques cardiovasculaires. Dans cette situation, l’échographie est l’examen recommandé pour l’évaluation de la stéatose. Lorsqu’une quantification précise de la stéatose est nécessaire, l’outil actuellement recommandé est l’IRM avec la technique multiéchos

Incidental focal solid liver lesions: diagnostic performance of contrast-enhanced ultrasound and MR imaging

International audienceObjective To prospectively assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) and MR imaging in incidental solid focal liver lesions not characterised on ultrasound. Materials and methods Forty-seven patients with 50 lesions underwent MR imaging and CEUS: 24 focal nodular hyperplasias (FNH), 11 adenomas, 10 haemangiomas, 1 focal fatty change and 4 malignant lesions were identified. Two experienced radiologists randomly reviewed contrast-enhanced MR imaging and CEUS data, and provided the most likely diagnosis. Sensitivity (Se), specificity (Sp), likelihood ratios (LR) and kappa value were calculated. Results A histotype diagnosis was obtained in 66–52% with MR imaging and 52–53% with CEUS, respectively, for both readers. Se, Sp and LR for haemangioma were 100–100, 100–100 and 78–78 with MR imaging and 89–89, 100–100 and 68–70 with CEUS; for FNH with MR imaging they were 88–63, 96–100 and 23–34 and 74–67, 88–96 and 6–17 with CEUS. If the diagnosis of haemangioma was uncertain with CEUS, MR imaging always confirmed the diagnosis. If the diagnosis of FNH was uncertain with either CEUS or MR imaging, the other imaging technique confirmed the diagnosis in approximately half the cases. Conclusion Both CEUS and MR imaging have a high diagnostic performance in incidental focal liver lesions and are complementary when diagnosis is uncertain.</p

Imaging after percutaneous thermal and non-thermal ablation of hepatic tumour: normal appearances, progression and complications

International audienceThe increasing number of liver tumours treated by percutaneous ablation leads all radiologists to be confronted with the difficult interpretation of post-ablation imaging. Radiofrequency and microwave techniques are most commonly used. Recently, irreversible electroporation treatments that do not induce coagulation necrosis but cellular apoptose and respect the collagen architecture of bile ducts and vessels have been introduced and lead to specific post-ablation features and evolution. Ablations cause ‘normal’ changes in ablation and periablation zones. It is necessary to know these post-ablation features to avoid the misinterpretation of recurrence or complication that would lead to unnecessary treatments. Another challenge for the radiologist is to detect as early as possible the residual unablated tumour or the disease progression (local progression and tumour seeding) that will require a new treatment. Finally, the complications, frequent or rarer, should be recognised to be managed adequately. The purpose of this article is therefore to describe the large spectrum of normal and pathological aspects related to the treatment of hepatic tumour by percutaneous thermal ablation and irreversible electroporation ablation

Feasibility and validity of monitoring subarachnoid hemorrhage by a noninvasive MRI imaging perfusion technique: Pulsed Arterial Spin Labeling (PASL)

International audienceBACKGROUND AND PURPOSE: To evaluate the validity of pulsed arterial spin labeling (PASL) imaging with cerebral blood flow (CBF) quantification for monitoring subarachnoid hemorrhage (SAH); to describe changes in the perfusion signal in the absence of or following several classic complications.MATERIALS AND METHODS: Fifteen patients and 14 healthy volunteers were assigned to SAH and control populations, respectively. ASL imaging was performed three times: between Day 0 (D0, i.e., day of onset of SAH symptoms) and D3, between D7 and D9 and between D12 and D14. ASL points were classified as complicated (symptomatic vasospasm, intraparenchymal hematoma or severe intracranial hypertension) or uncomplicated. Perfusion and CBF maps were generated after automated processing. The inversion time (TI) was fixed at 1800 ms.RESULTS: CBF mean value of Day0-3 uncomplicated SAH patients (47 ± 11.7 mL/min/100g) was significantly higher than that of the volunteers (36.5 ± 7.6 mL/min/100g; P=0.014). In a case-by-case analysis, we observed a global or regional hypoperfusion pattern when SAH was complicated by vasospasm or severe intracranial hypertension, particularly at the junctional areas. Furthermore, we have faced major vascular artefacts, visible as serpiginous high signals and related to the retention of labeled protons in arteries concerning by angiographic vasospasm.CONCLUSION: PASL is an interesting perfusion technique to non-invasively highlight perfusion changes in complicated SAH and can provide a new element in the decision to perform urgent endovascular treatment. However, the increase in arterial transit time makes the Buxton quantification model inapplicable and leads to false high CBF values in the single-TI PASL technique.Copyright © 2015 Elsevier Masson SAS. All rights reserved