Chemically Enhanced Convective Dissolution of CO_{2}.

Convective dissolution, one of the main mechanisms for geological storage of CO_{2}, occurs when supercritical or gas CO_{2} dissolves partially into an aqueous solution, thus triggering downward convection of the denser CO_{2}-enriched liquid. Chemical reaction in the liquid can greatly enhance the process. Here, experimental measurements of convective flow inside a cylinder filled with a sodium hydroxide (NaOH) solution show that the plume's velocity can be increased tenfold as compared to a situation with no NaOH. This tremendous effect is predicted by a model with no adjusting parameters.

[Chest radiological lesions in COVID-19 : from classical imaging to artificial intelligence]. / Les aspects radiologiques de la pneumopathie à COVID-19 : de l'imagerie conventionnelle à l'intelligence artificielle.

In the course of the pandemic induced by the appearance of a new coronavirus (SARS-CoV-2; COVID-19) causing acute respiratory distress syndrome (ARDS), we had to rethink the diagnostic approach for patients suffering from respiratory symptoms. Indeed, although the use of RT-PCR remains the keystone of the diagnosis, the delay in diagnosis as well as the overload of the microbiological platforms have led us to make almost systematic the use of thoracic imaging for taking in charge of patients. In this context, thoracic imaging has shown a major interest in diagnostic aid in order to better guide the management of patients admitted to hospital. The most common signs encountered are particularly well described in thoracic computed tomography. Typical imaging combines bilateral, predominantly peripheral and posterior, multi-lobar, ground glass opacities. Of note, it is common to identify significant lesions in asymptomatic patients, with imaging sometimes preceding the onset of symptoms. Beyond conventional chest imaging, many teams have developed new artificial intelligence tools to better help clinicians in decision-making.

Dans le décours de la pandémie induite par l'apparition d'un nouveau coronavirus (SARS-CoV-2; COVID-19) à l'origine d'un syndrome de détresse respiratoire aigu (SDRA), nous avons dû repenser l'approche diagnostique des patients souffrant de symptômes respiratoires. En effet, bien que l'usage de la RT-PCR reste la clé de voûte du diagnostic, le retard de diagnostic ainsi que la surcharge des plateformes microbiologiques nous ont menés à rendre quasi systématique l'usage de l'imagerie thoracique pour la prise en charge des patients. L'imagerie thoracique a démontré, dans ce contexte, un intérêt majeur dans l'aide au diagnostic afin d'orienter, au mieux, la prise en charge des patients admis à l'hôpital. Les signes les plus couramment rencontrés sont particulièrement bien décrits en tomodensitométrie thoracique. L'imagerie typique associe des lésions en verre dépoli bilatérales, multi-lobaires, à prédominance périphérique et postérieure. Il est classique d'identifier des lésions significatives chez des patients asymptomatiques, l'imagerie précédant parfois l'apparition de symptômes. Au-delà de l'imagerie thoracique conventionnelle, de nombreuses équipes ont développé de nouveaux outils d'intelligence artificielle afin d'aider, au mieux, les cliniciens dans la prise de décisions.

[Exploration of urethral strictures : place of urethrocystography]. / Comment j'explore les sténoses urétrales : intérêt de l'urétrocystographie.

Stricture of the male urethra is a frequent and regularly iatrogenic pathology in industrialized countries. The urologist's surgical arsenal is wide and the choice of an operative technique is made at the end of an assessment where urethrocystography is the main radiological examination. The conditions to achieve the examination, its different stages, the normal aspects and anatomical variants as well as the limitations to its interpretation, should therefore be known by the urologist and the radiologist, in order to assess correctly this pathology.

La sténose de l'urètre masculin est une pathologie fréquente, régulièrement iatrogène dans les pays industrialisés. L'arsenal chirurgical de l'urologue face à celle-ci est large et le choix d'une technique opératoire est posé au terme d'un bilan dont l'urétrocystographie occupe une place centrale. Les conditions de réalisation de l'examen, ses étapes, les aspects normaux et les quelques variantes anatomiques ainsi que ses limites d'interprétation, doivent donc être connus de l'urologue et du radiologue, de manière à ne pas méconnaître ou, au contraire, surestimer une sténose urétrale.

Increased risk of mortality in systemic sclerosis-associated digital ulcers: a systematic review and meta-analysis.

BACKGROUND: Survival can be threatened in certain forms of systemic sclerosis (SSc) so clear prognostic factors are needed. OBJECTIVES: The aim of this meta-analysis was to assess the association between the presence of digital ulcers (DUs) and mortality in SSc. METHODS: We performed a systematic review and meta-analysis in the Pubmed and Scopus databases from the earliest records to May 2017. Two research strategies were performed: « systemic sclerosis ¼ and « digital ulcers ¼ (strategy A); « systemic sclerosis ¼ and « mortality ¼ (strategy B). The primary outcome was the mortality associated with the presence of DUs in patients with SSc. RESULTS: The literature search identified 1473 citations. Fifty-nine studies were examined for full text. Ten articles were included for the meta-analysis. SSc patients with DUs had an increased pooled mortality risk: RR = 1.53 (IC 95%: [1.23-1.90]). CONCLUSIONS: This meta-analysis revealed a higher mortality in SSc patients with associated DUs. Having DUs may be a predictive factor of developing organ involvement such as pulmonary or cardiovascular events that could be associated with poor survival. It suggests that early screening of DUs in SSc patients is important to identify patients most at risk of poor survival.

[Cystic nephroma : a rare kidney neoplasm]. / Le cas clinique du mois. Le néphrome kystique : une tumeur rénale rare.

Cystic nephroma is a rare kidney neoplasm belonging to the entity of cystic tumours. It is a slow-growing tumour, which develops insidiously, sometimes reaching a considerable size. The diagnosis is more often accidental (except for mass syndrome in children). It is a benign tumour that may be treated by partial sparing nephrectomy. Malignant degeneration is few and far between. However, no medical examination can confirm the diagnosis before surgery. On medical imaging, the tumour enhances after contrast injection and there will always be a doubt about the benignity. Furthermore, percutaneous biopsy of the mass is not contributory to the diagnosis. This means that it is not easy to propose a conservative surgical treatment, even though this remains the best way to deal with such a tumour.

Le néphrome kystique («Cystic Nephroma¼) est une tumeur rare appartenant au spectre des tumeurs rénales kystiques. Sa croissance est lente et il se développe de manière insidieuse, atteignant parfois une taille importante. Ainsi, sa découverte est le plus souvent fortuite (syndrome de masse chez les enfants et incidentalome chez les adultes). Il s'agit d'une pathologie bénigne pouvant être traitée par chirurgie conservatrice d'épargne néphronique. La dégénérescence maligne est rarissime. Cependant, aucun examen médical ne permet de poser un diagnostic de certitude avant l'intervention chirurgicale. A l'imagerie, la lésion se rehausse après injection de produit de contraste, et il persiste toujours un doute quant à sa bénignité. Par ailleurs, la biopsie d'une telle lésion kystique n'est pas contributive. Ainsi, il n'est pas toujours aisé de poser l'indication de traitement conservateur, bien qu'il soit préférable pour le patient.

[Exploring focal liver lesions with contrastenhanced ultrasonography]. / Comment j'explore... Une lésion hépatique focale par une échographie de contraste.

Noninvasive diagnosis of focal liver lesions is usually based on unenhanced ultrasonography, computed tomography, or magnetic resonance. Contrast-enhanced ultrasonography (CEUS) can be used among the other imaging modalities in evaluating these lesions. The technique requires the intravenous injection of contrast media. Ultrasound contrast agents are very safe and the technique doesn't involve any radiation. A large body of evidence supports and clarifies the role of CEUS in evaluating focal liver lesions. Hemangiomas, focal nodular hyperplasia, focal fatty change will be diagnosed in a majority of cases and CEUS is also helpful in distinguishing malignant from benign lesions.

Le diagnostic non invasif des lésions hépatiques focales repose habituellement sur l'échographie conventionnelle, la tomodensitométrie ou l'imagerie par résonance magnétique. L'échographie de contraste vient s'ajouter à l'arsenal des techniques d'imagerie disponibles et peut être utilisée dans la mise au point de ces lésions. Elle requiert l'utilisation de produits de contraste ultrasonores qui sont injectés en intraveineux. Ceux-ci présentent un excellent profil de sécurité et le caractère non irradiant de la technique est un avantage supplémentaire. De nombreuses publications illustrent la contribution et la place de l'échographie de contraste dans le bilan des lésions hépatiques focales. Elle est performante dans le diagnostic d'hémangiome, d'hyperplasie nodulaire focale et de stéatose hétérogène, et s'avère également contributive dans l'exploration des lésions malignes.

[Multidisciplinary management of alveolar echinococcosis : Echino-Liege Working Group]. / Prise en charge multidisciplinaire de l'échinococcose alvéolaire : le groupe Echino-Liège.

Alveolar echinococcosis is a zoonotic disease due to the tapeworm Echinococcus multilocularis. The definitive host is the red fox. Until recently, Belgium was considered a country at very low risk for alveolar echinococcosis. However, recent studies carried out in southern Belgium have revealed, through post-mortem examination, high prevalences (up to 62 %) in foxes. Cats and dogs can act as definitive hosts. Human are accidentally infected by ingestion of food contaminated by the feces. After a long incubation period, invasive hepatic lesions may appear, as well as extra-hepatic lesions. The disease may be fatal. The diagnosis is based on imaging techniques, serology and nucleic acid detection in tissues. Early diagnosis may allow surgical removal of the lesion associated with at least 2 years of albendazole postoperative treatment. In case of contraindication to surgery, a long term treatment with albendazole is necessary. Liver transplantation is sometimes necessary. This article presents the epidemiologic, clinical, diagnostic and therapeutics features of this zoonotic disease.

L'échinococcose alvéolaire est une zoonose due à Echinococcus multilocaris, un cestode, dont l'hôte définitif est le renard roux (Vulpes vulpes). Jusqu'il y a peu, la Belgique était un pays considéré comme à très faible risque pour cette parasitose, mais de récentes autopsies de renards ont montré des prévalences élevées chez ceux-ci (pouvant dépasser les 60 %). Les chiens et les chats peuvent également être des hôtes définitifs. La transmission humaine (hôte accidentel) se fait principalement via la consommation d'aliments souillés par les déjections animales contaminées donnant, après une longue période d'incubation, des lésions hépatiques infiltrantes et, éventuellement, des atteintes extra-hépatiques pouvant être mortelles. Le diagnostic est fondé sur l'imagerie médicale couplée à des tests sérologiques et la PCR sur des tissus. La prise en charge curative est chirurgicale, lorsque la résection complète est possible. Elle est associée à un traitement de deux ans post-opératoire à base d'albendazole. En cas d'impossibilité de résection complète, un traitement au long cours par de l'albendazole est préconisé. Enfin, dans certains cas, une transplantation hépatique peut être envisagée. En raison de l'augmentation des cas autochtones rencontrés en Wallonie, un groupe spécialisé dans la prise en charge de l'échinococcose a été créé au sein de l'université de Liège. Cet article illustre les caractéristiques épidémiologiques, cliniques, diagnostiques et thérapeutiques de cette zoonose.

[How I explore Crohn's disease by various imaging modalities]. / Comment j'explore la maladie de Crohn par imagerie.

Crohn's disease is a chronic inflammatory condition characterized by recurrent and/or chronic lesions, leading to cumulative structural bowel damage. It is established that the correlation between symptoms and intestinal lesions is weak. Therefore, monitoring by frequent cross-sectional imaging is proposed to assess the disease activity. There is no consensus about the preferred imaging option. Priority is given to non-radiating modalities, such as ultrasonography and MRI. Tomodensitometry will be reserved for emergency cases. Ultrasonography can be useful, in emergency as well as for the monitoring of lesions of known topography. Entero-MRI is henceforth considered the standard imaging technique for the diagnosis and follow-up of Crohn's disease. Its high contrast resolution allows an accurate assessment of disease activity, therapeutic efficacy, cumulative structural bowel damage and complications.

La maladie de Crohn est une maladie inflammatoire intestinale dont les manifestations récurrentes ou chroniques entraînent des dommages tissulaires cumulatifs. Il est avéré que la corrélation entre la symptomatologie clinique et les lésions intestinales est faible. Par conséquent, des examens d'imagerie fréquents sont nécessaires pour déterminer l'activité de la maladie. Il n'existe pas de consensus quant à l'utilisation de l'une ou l'autre technique. La priorité sera donnée à des examens peu irradiants comme l'échographie et l'IRM. La tomodensitométrie sera réservée aux situations d'urgence ou en cas de contre-indication à l'IRM. L'échographie est un outil à ne pas négliger, tant en urgence que pour le suivi de lésions de topographie connue. L'entéro-IRM est dorénavant l'examen de choix pour le diagnostic et le suivi de la maladie de Crohn. Son excellente résolution en contraste permet d'évaluer l'activité de la maladie, l'efficacité thérapeutique, les dommages tissulaires cumulés et la présence de complications.

[STRICTURING CROHN'S DISEASE: CLINICAL FEATURES, DIAGNOSIS AND TREATMENT]. / LA MALADIE DE CROHN STÉNOSANTE: Présentation clinique, diagnostic et modalités de traitement.

Crohn's disease (CD) is a chronic inflammatory bowel disease which mainly affects young people. This disease evolves in successive steps and is often complicated by strictures which express characteristic signs of occlusive syndrome, more often in case of ileal than colonic involvement. The nature and localisation of strictures should be precisely defined by different techniques like endoscopy, entero-(colo)-scanner or entero-(colo)-MRI. This work-up is essential to best adapt the therapeutic care. Indeed, the fibrosing evolution of inflammatory strictures causes medical treatment's failure which may lead to endoscopic dilatation or surgical resection. To avoid this negative evolution, it is mandatory to adopt early therapeutic strategy to control inflammation.

[AUTOSOMAL DOMINANT POLYCYSTIC KIDNEY DISEASE: HOW AND WHY SHOULD WE IDENTIFY THE PATIENTS "RAPIDLY PROGRESSING" TO END-STAGE RENAL DISEASE?]. / LA POLYKYSTOSE RÉNALE AUTOSOMIQUE DOMINANTE: comment et pourquoi identifier les patients "rapidement progresseurs" vers l'insuffisance rénale terminale?

Autosomal dominant polycystic kidney disease (ADPKD) is a common inherited disease characterised by the progressive development of multiple and bilateral cysts in kidneys and other organs. Most patients with ADPKD will develop, sooner or later, end-stage renal disease (ESRD). The morbidity and mortality associated with ESRD prompt physicians to identify early ADPKD patients considered as "rapid progressors", who have the greatest risk to rapidly develop ESRD. The rate of progression can be assessed by clinical--especially with the "predicting renal outcome in polycystic kidney disease score" (PROPKD-Score)-, biological (a decline of the glomerular filtration rate (GFR) of 4.4-5.9 ml/min/year and/or the doubling of serum creatinine within a 36-month period), or radiological criteria (total kidney volume (TKV) adjusted for the size > 600 cc/m and/or TKV annual growth rate > 5 %). Nowadays, there is no curative treatment for ADPKD. However, vasopressin-2 receptor antagonists, such as tolvaptan, appear to slow down the growth of renal cysts and the slope of GFR decline. The current management of ADPKD patients is mostly based on correcting the risk factors for progression, i.e. encouraging (over)-hydration, normalizing blood pressure, stimulating smoking cessation.

[Point-of-care ultrasound in emergency department : a case report of acute dyspnea during pregnancy]. / Apport de l'échographie thoracique aux urgences : à propos d'un cas de dyspnée aiguë durant la grossesse : cas clinique.

On the basis of the case report of a pregnant woman with acute pleuritis, this article describes the diagnostic modalities of dyspnea during pregnancy. The utility and effectiveness of bedside ultrasound examination by the emergency physician («POCUS¼) are reviewed in view of recent literature data. The ultrasound in this case is considered to be the extension of physical examination aiming at providing answers with immediate clinical relevance.

Au départ du cas clinique d'une femme enceinte présentant une pleurésie, cet article détaille la mise au point d'une dyspnée durant la grossesse. L'utilité et l'efficacité d'un examen échographique pulmonaire par l'urgentiste au chevet du malade («POCUS¼) sont revues à la lumière des données récentes de la littérature. L'échographie dans ce cas est un parfait prolongement de l'examen clinique et vise à apporter des réponses dont l'intérêt clinique est immédiat.

[ABOUT JUVENILE NASOPHARYNGEAL ANGIOFIBROMA]. / A PROPOS DE L'ANGIOFIBROME NASOPHARYNGIEN JUVÉNILE.

We report the case of a young man with a juvenile nasopharyngeal angiofibroma. In this paper, we will first remind the clinical signs of this pathology and its radiological appearance (localisation and extensions). Then we will explain how radioembolisation techniques were used to facilitate the surgical intervention. Finally we will discuss the histology of this tumor.

[FROM EVIDENCE-BASED MEDICINE TO PERSONALIZED MEDICINE IN CROHN'S DISEASE]. / DE L'"EVIDENCE-BASED MEDICINE" À LA MÉDECINE PERSONNALISÉE DANS LA MALADIE DE CROHN.

The therapeutic armamentarium in Crohn's disease includes mesalazine, steroids (including topical drugs), anti-metabolites (purines, methotrexate), anti-TNFα antibodies and, more recently, selective inhibitors of lymphocytes homing (vedolizumab). The efficacy of these drugs has been shown in pivotal phase 3 placebo-controlled trials and meta-analyses. However, the use of these drugs in routine practice still remains ill-defined. Those are rather the cohort studies, natural history data and therapeutic strategy trials that help the clinician to determine, for each individual patient, the treatment leading to an optimal benefit/risk profile, aiming at moving from evidence-based medicine towards personalized medicine.

[Evolution in the therapeutic strategy of localized resectable pancreatic ductal adenocarcinoma]. / Evolution dans la prise en charge de l'adénocarcinome du pancréas localisé estimé résécable.

Pancreatic ductal adenocarcinoma is characterized by a high rate of early metastatic relapse. Surgical resection is still recognized as the cornerstone upfront therapy. However, reported 5 years survival rates are inferior to 20-25% even when surgery is followed by chemotherapy. Margins involvement on the surgical specimen (50 to 85%) and lymph node involvement (around 70%) both strongly impact survival. Median survivals are close to those of locally advanced diseases treated by chemotherapy or chemoradiotherapy, 15 to 16 months. This review focuses on adverse prognostic factors, post-operative outcomes and their impact on multimodality therapy completion rates and survivals in patients undergoing upfront surgery. Current data and emerging results from neoadjuvant series could lead to a change in the therapeutic strategy.

[Functional imaging and radiotherapy]. / Utilisation de l'imagerie fonctionnelle en radiothérapie.

Medical imaging plays a crucial role in the diagnosis, staging and therapeutic strategy of oncologic patients. The development of medical imaging over the last decade has allowed significant progresses in radiotherapy. Indeed, medical imaging is now considered the corner stone of radiotherapy. The main challenge for the radiation oncologist consists in the tumour identification with a view to irradiate the tumour at a curative dose while avoiding healthy tissues. To achieve these goals, the radiotherapist daily uses anatomical imaging such as computed tomography (CT) or magnetic resonance imaging (MRI). Since several years now, the development of functional imaging such as positron emission tomography (PET) combined with CT or functional MRI has opened new perspectives in the management of oncologic diseases. Indeed, these imaging techniques offer new information on tumour metabolism that may be taken into account to plan the radiotherapy treatment. This article illustrates the different imaging techniques used in radiotherapy and the role of functional imaging for establishing new therapeutic strategies in radiation oncology.

[Iodinated contrast media and iodine allergy: myth or reality?]. / Produits de contraste iodés et "allergie a l'iode" mythe ou réalité ?

The term "iodine allergy" is an old phrase that refers to a reaction to iodinated contrast media. After a brief review of definitions, pathophysiological mechanisms and risk factors of this clinical entity, management is urged immediate and delayed according to the most recent recommendations from the literature. We underline that iodine allergy, as such, does not really exist.

[Crohn's disease and MRI: assessment of inflammatory activity and tissue damage]. / Maladie de Crohn et entéro-IRM évaluation de l'activité de la maladie et du dommage tissulaire.

Crohn's disease is an inflammatory bowel disease that affects mainly young people and includes periods of remission interspersed with occasional flare-ups. Entero-MR (Magnetic Resonance) is a non-radiating and a non-invasive tomography imaging technique. Entero-MR has recently proven its ability to assess inflammatory activity and structural damage of the bowel in Crohn's disease which are fundamental elements in the therapy planning. These considerations explain why entero-MR is playing an increasing role in the evaluation of Crohn's disease.

[Fifteen years of use of anti-TNF antibodies in moderate to severe Crohn's disease: how to make the best of this experience]. / Quinze ans d'anti-TNF dans la maladie de Crohn: comment tirer le meilleur de cette révolution thérapeutique?

After fifteen years of use, the anti-TNF antibodies have become the corner stone of the treatment of moderate and severe Crohn's disease. The skill acquired over the years through experimental trials and clinical experience leads to increased therapeutic efficacy and minimized risks. These antibodies are introduced increasingly earlier in Crohn's disease as well as in a broader range of patients, aiming at changing the natural history of the diseases by avoiding the development of intestinal tissue damage and complications.

[Clinical case of the month. Portal venous gas due to a hydrogen peroxide colic enema]. / Le cas clinique du mois. Aéroportie due a un lavement a l'eau oxygénée.

Portal venous gas is a worrying radiological sign that was described for the first time in 1955 among newborn children suffering from necrotizing enterocolitis. It was often related to mesenteric ischemia which mortality remains very high. Now, as radiological explorations increase, portal venous gas is more and more described in less pejorative contexts, such as hydrogen peroxide intoxication. It is what happened to our patient who underwent a hydrogen peroxide colic enema followed by a major and transient portal venous gas onset. This solved quickly and spontaneously.

In osteoporotic women treated with strontium ranelate, strontium is located in bone formed during treatment with a maintained degree of mineralization.

UNLABELLED: In postmenopausal osteoporotic women and up to 3 years of treatment with strontium ranelate, strontium was present only in recently deposited bone tissue resulting from formation activity during the period of treatment. Strontium was shown to be dose-dependently deposited into this newly formed bone with preservation of the mineralization. INTRODUCTION: Interactions between strontium (Sr) and bone mineral and its effects on mineralization were investigated in women treated with strontium ranelate. METHODS: Bone biopsies from osteoporotic women were obtained over 5-year strontium ranelate treatment from phases II and III studies. Bone samples obtained over 3-year treatment were investigated by X-ray microanalysis for bone Sr uptake and focal distribution, and by quantitative microradiography for degree of mineralization. On some samples, Sr distribution (X-ray cartography) was analyzed on whole sample surfaces and the percentage of bone surface containing Sr was calculated. Bone Sr content was chemically measured on whole samples. RESULTS: In treated women, Sr was exclusively present in bone formed during treatment; Sr deposition depended on the dose with higher focal content in new bone structural units than in old ones constantly devoid of Sr, even after 3-year treatment. A plateau in global bone Sr content was reached after 3 years of treatment. Cartography illustrated the extent of surfaces containing Sr, and formation activity during strontium ranelate treatment was higher in cancellous than in cortical bone. Mineralization was maintained during treatment. CONCLUSION: The quality of bone mineral was preserved after treatment with strontium ranelate, supporting the safety of this agent at the bone tissue level.