Abstract Background Perianal fistulising Crohn’s disease (CD) is a disabling condition affecting up to 30% of patients. Studies suggest that greater fibrosis in the fistula tract is linked to improved clinical outcomes. This study aims to describe the natural history of perianal fistulising CD, including MRI parameters, and to identify clinical and radiological predictors of relapse and radiological healing Methods Pelvic MRIs for perianal fistula performed at CHU Liège, Belgium, from 2018 to 2023 were collected. MRI protocols used 1.5T [Siemens Aera/Sola] or 3T [Siemens Vida] machines, with sequences including T2 TSE, T2 TSE FS, and T1 TSE FS before and after gadolinium injection. The MAGNIFI-CD and modified Van Assche (VA) indices were assessed for each patient. Two blinded radiologists evaluated fistula tract fibrosis. For patients with perianal flare, only the first MRI was analysed (MRI 1). For others, the first and last MRI (MRI 2) within the study period were assessed. Perianal flare was defined as abscess drainage or stoma creation for active perianal CD, and radiological healing as ≥80% fistula fibrosis or a MAGNIFI-CD score of 0. Results A total of 102 pelvic MRIs from 84 patients were included. The median patient age was 39 years (31–51), with 40% female. The median duration of perianal CD was 52 months (2–144); 26% had a seton at MRI 1, 7% had a stoma, and 41% were on anti-TNF therapy. During follow-up, 22% required abscess drainage. No clinical factors were associated with perianal flare. Univariate analysis identified several MRI 1 radiologic predictors of flare: fibrosis percentage (OR=0.72, p=0.033), VA hyperintensity T2 (OR=3.22, p=0.028), VA rectal involvement (OR=1.75, p=0.040), VA inflammatory mass (OR=1.42, p=0.022), VA T1 post-contrast hyperintensity (OR=3.68, p=0.045), MAGNIFI-CD score (OR=1.13, p=0.022), MAGNIFI T1 post-contrast hyperintensity (OR=1.77, p=0.031), and MAGNIFI inflammatory mass (OR=1.40, p=0.033). In multivariate analysis, only MAGNIFI T1 post-contrast hyperintensity remained significant (OR=1.77, p=0.031). Radiological healing was achieved in 30% at MRI 1 (25/84) and 44% at MRI 2 (8/18). No factors at MRI 1 predicted healing at MRI 2, though T1 post-contrast hyperintensity at MRI 1 showed a trend towards predicting lack of healing (OR=0.11, p=0.071). Conclusion One-fifth of patients experienced perianal flare during follow-up. Clinical and therapeutic factors did not predict outcomes; only persistent MRI inflammation and low fistula fibrosis were linked to future abscess drainage. Specific MRI features may serve as therapeutic targets in perianal CD management, pending validation in a prospective cohort.

Early detection of COVID-19 infection, followed by appropriate patient management, has the potential to reduce costs related to developing severe forms of the disease, as well as spreading of the disease, if left undetected. Our objective was to evaluate the impact of an AI-based chest CT analysis software (icolung, icometrix) for the detection and prognosis of COVID-19 cases in patients receiving a CT scan in a hospital setting in Belgium. We developed a decision analytic model comparing routine practice scenario where patients receiving a CT scan in the hospital are not screened for COVID-19 with a scenario where icolung is used to analyze CT scans for the detection and prognosis of COVID-19 cases. We evaluated the impact of the technology in preventing the further spreading of the infection in the community and in reducing the length of hospitalization of COVID-19 patients. In the base case using a relatively low COVID-19 prevalence of 0.36%, icolung is cost-effective in preventing COVID-19 transmission in the community, costing € 8.221 to prevent one infection. At low prevalence of the disease and low risk of hospitalization, the technology is not cost-effective in reducing the length of hospitalization. However, icolung may be cost-effective in situations with high disease prevalence (>30%) or high risk of hospitalization (>6%) such as patients suffering from chronic oncological diseases and benefiting from recurring thoracic imaging. This model provides initial evidence of cost-effectiveness of AI-based chest CT analysis software and may help to provide guidance regarding further health care research and policy.

Abstract Background Anoperianal lesions affect up to 30% of patients with Crohn’s disease (CD). Long-term fistula healing is challenging with conventional biotherapies. Although recent studies demonstrated the efficacy of local injections of adipose tissue-derived stem cells with 50 % of fistulae closure without abscess at one year, this treatment is not available in routine. The primary aim of this study was to evaluate the safety and the feasibility of the injection of bone marrow-derived mesenchymal stem cells isolated and prepared in a local university laboratory of cell therapy for perianal fistulizing CD. The second aim was to evaluate the efficacy of this treatment and his impact on the quality of life of the patients. Methods A prospective observational study was performed in the CHU of Liège from October 2019 till October 2021. All CD patients with perianal fistula and seton placement for at least 6 months were eligible. PRO, clinical examination, CRP, fecal calprotectine, CDAI, Short health scale (SHS) and MRI were performed at weeks 0, 12 and 48. PDAI was calculated at inclusion and at Week 48. Efficacy was defined as closure of all treated external openings at clinical examination without abscess at MRI. Results Sixteen patients with a median age of 49 years old and a median duration of perianal CD of 8 years were included. Eleven (69%) patients were on anti-TNF. CDAI and PDAI at inclusion were 97,5 ± 48,8 et 5 ± 4,4 respectively. Four (25%) patients reported adverse events the week after the injection (local pain 3/16, mild bleeding 1/16), all of them quickly resolutive. Ten (63%) and 8 (50%) patients had a closure of all the external opening at week 12 and 48 respectively. Five out of 6 patients with 2 external openings had at least 1 opening closed at Week 48. One abscess was observed during the follow-up. The median PDAI was numerically lower at the end of the study (3 versus 5 at the inclusion). The quality of life improved with a regression of the SHS from 10 to 7.5 at the end of the follow-up. At MRI, MAGNIFI-CD score and Van Assche index were similar for each patients at the inclusion and at the end of the study. Conclusion Injection of locally prepared bone marrow-derived mesenchymal stem cells seems safe and effective in refractory perianal fistulae in Crohn’s disease with 50% of closure at 1 year. The treatment is associated with an improvement of the perianal activity scores and the quality of life scores but not with the MRI scores.

Introduction: CT imaging has been widely used during the COVID-19 pandemic to diagnose and assess disease severity. Its use for diagnosis is not indicated apart from specific settings such as triage of patients for referral to RT-PCR testing or severity assessment. Nowadays, the added value of AI-based models is still unknown and has to be addressed. Methods: We evaluated the added value of an automated lung involvement assessment tool, named icolung. Since software version 7.0, icolung automatically extracts the Severity Score proposed by Pan F. et al., (2020, Radiology), to help radiologists assess the severity of lung involvement in COVID-19 infected patients. We evaluate retrospectively a group of 785 COVID-19 positive patients compared to a group of 1049 COVID-19 negative patients. We used the severity score (SS) in order to predict the positivity of COVID-19 PCR testing and evaluated the potential impact in the prediction of patients’ outcome. Results: The icolung SS allows to identify infected (PCR-proven) COVID-19 patients with a sensitivity of 83% and a specificity of 77% (AUC of 0.86, 95% CI 0.85-0.88) for patients with a SS of more than 1.5 on a scale of 0 to 25. An SS of > 7.5 identifies patients at risk of ICU admission with a sensitivity of 70% and specificity of 65% (AUC of 0.74, p<0.0001). Conclusion: The severity score as estimated via icolung allows to identify positive PCR-tested COVID-19 patients and helps to predict ICU admission. This automated evaluation tool can support clinicians with the in-hospital management of patients (suspected to be) infected with COVID-19.

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.

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.

COVID-19 associated lung diseases can mimic radiological characteristics of other viral lung diseases such as influenza which may lead to misdiagnosis. In this study, we proposed an Artificial Intelligence framework based on a combination of a Convolutional Neural network architecture and a Recurrent Neural Network architecture to classify CT volumes with COVID-19, Influenza, and no-infection. The model was trained on a dataset of 300 patients (100 patients in each class). Each set of 15 consecutive axial slices with the associated label of the corresponding CT volume was input as a 3 channel input at 5 time points to the CNN-RNN network. Benchmarked against RT-PCR confirmed cases of COVID-19 and Influenza, our model, when evaluated on an independent validation set of 400 CT patients, can accurately classify CT volumes of patients with COVID-19, Influenza, or no-infection with a sensitivity of 96% (COVID-19) and 95% (Influenza) (Table1). Figure1 shows the percentage of correctly classified and misclassified cases in each class. Our model provides rapid accurate diagnosis in patients suspected of COVID-19 infection, facilitating the timely implementation of isolation procedures and early intervention.

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.

BACKGROUND AND STUDY AIMS:The current standard of care for resectable pancreatic ductal adenocarcinoma (PDAC) is surgery-first followed by adjuvant chemotherapy. We review our single center experience in a PDAC cohort managed by the surgery-first strategy. We then compare our data to those of Belgian and international literature. PATIENTS METHODS:We reviewed a series of 83 consecutive resectable patients with PDAC, treated by the surgery-first approach in a Belgian Academic Hospital between 2007 and 2013. The outcomes were assessed with univariate and multivariate Cox regression analysis. Kaplan-Meier curves were drawn according to patient groups. RESULTS:For the entire population, the median survival (MS) was 18.4 months; the 1-year relapse-free survival was 56%, and the 5-year overall survival (OS) was 13%. The size of the primary tumor larger than 3 cm (OS, HR = 1.76, p = 0.033) and vascular resection (DFS, HR = 2.1, p = 0.024) were the single independent prognostic factors in the multivariate analysis of this cohort. Only 69% of the patients received adjuvant chemotherapy, and more than 75% of them demonstrated no chance of survival beyond 3 years because they harbored poor prognostic factors, recognized only postoperatively. CONCLUSIONS:Our results and those published in the literature brought to light the limited perspectives of the surgery-first strategy in a population of apparently resectable pancreatic cancers. In comparison, data from reported neo-adjuvant series deserve our interest to bring this strategy upfront in selected patients in the context of close observational monitoring and randomized trials. The actual standard of care for resectable PDAC is surgery-first followed by adjuvant chemotherapy. The performance of this strategy relies on the dedicated imaging that does not accurately recognize the limits of the tumor and the high prevalence of adverse prognostic factors. Moreover, pancreatectomy remains associated with high postoperative complication rates and the poor completion of adjuvant therapy. This translates into poor long-term survival figures. In our series the MS was 18.4 months and 5-year OS was 13%. The disease-free survival (DFS) was 15.6 months, 1 and 3-year DFS were 56 and 26%, respectively. The variables that significantly correlated with OS in univariate analysis are tumor size and lymph node involvement. Regarding DFS, vascular resection was the only significant factor. In the multivariate analysis, the only significant factor related to OS remained the tumor size >3 cm in greatest diameter. Vascular resection remained significant for DFS. 31% of the patients did not receive any chemotherapy at all before the 6-month period following resection. The rates of complete resections compared favorably with those of a surgery-first strategy with no excess of operative mortality, complications and early relapse rates. The advantages of a chemotherapy-first approach, eventually combined with chemo-radiotherapy, are to offer higher combined therapy completion rates and improve the level of free resection margins, lymph node involvement and patient selection. The advent of safe, more potent chemotherapy combinations has the potential to further improve survival when administered upfront.

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.

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.

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 («POCUS») 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.

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 (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.

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.

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.

INTRODUCTIONOur goals were to assess the prevalence of biological and tissue remission in routine practice in Crohn's disease, and to evaluate the correlation between biological or tissue remission and clinical or demographic characteristics as well as their impact on disease outcome.METHODSWe performed a retrospective monocenter study. Biological remission was defined by a CRP < 5 mg/I. Tissue remission was defined by the absence of ulcer at endoscopy and/or absence of signs of acute inflammation at MRI. Association with demographic, clinical and laboratory markers was studied by logistic regression models and rates of relapses, hospitalizations and surgeries were compared using the logrank test.RESULTSAmong the 263 patients included, 147 were in clinical remission; 102/147 (69%) were in biological remission. Fifty-six patients also had morphological evaluation: 37 (66%) were in tissue remission. Biological remission was associated with older age, higher hemoglobin and lower BMI. Tissue remission was associated with older age, lower platelets count, absence of previous surgery, and the use of immunosuppressant. Time-to-relapse was significantly longer in patients with biological remission and in patients with tissue remission as compared to patients without biological or tissue remission.CONCLUSIONSAmong the patients in clinical remission seen as outpatients, two thirds were either in biological and/or tissue remission. Biological and/or tissue remission was associated with a better outcome than clinical remission alone.

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.

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.

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.