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Objective Some patients (10 % – 32 %) with a positive guaiac fecal occult blood test (gFOBT) do not undergo the recommended colonoscopy. The aim of this study was to compare video capsule endoscopy (VCE) and computed tomography colonography (CTC) in terms of participation rate and detection outcomes when offered to patients with a positive gFOBT who did not undergo the recommended colonoscopy. Methods An invitation letter offering CTC or VCE was sent to selected patients after randomization. Acceptance of the proposed (or alternative) procedure and procedure results were recorded. Sample size was evaluated according to the hypothesis of a 13 % increase of participation with VCE. Results A total of 756 patients were targeted. Following the invitation letter, 5.0 % (19/378) of patients underwent the proposed VCE and 7.4 % (28/378) underwent CTC, ( P = 0.18). Following the letter, 9.8 % (37/378) of patients in the VCE group underwent a diagnostic procedure (19 VCE, 1 CTC, 17 colonoscopy) vs. 10.8 % in the CTC group (41/378: 28 CTC, 13 colonoscopy; P = 0.55). There were more potentially neoplastic lesions diagnosed in the VCE group than in the CTC group (12/20 [60.0 %] vs. 8/28 [28.6 %]; P = 0.04). Thus, 15/20 noninvasive procedures in the VCE group (19 VCE, 1 CTC; 75.0 %) vs. 10/28 in the CTC group (35.7 %; P = 0.01) resulted in a recommendation of further colonoscopy, but only 10/25 patients actually underwent this proposed colonoscopy. Conclusion Patients with a positive gFOBT result who do not undergo the recommended colonoscopy are difficult to recruit to the screening program and simply proposing an additional, less-invasive procedure, such as VCE or CTC, is not an effective strategy. ClinicalTrials.govNCT02558881TRIAL REGISTRATION: Randomized, controlled trial NCT02558881 at clinicaltrials.gov.

Rationale and objectives To evaluate the quality of images of the aorta and visceral arteries made at a high level of spatial resolution with thin slices and an optimized acquisition time by three-dimensional contrast-enhanced magnetic resonance angiography (3D CE-MRA). Materials and methods 3D CE-MRA with a 1.4-mm slice thickness and 512-pixel base matrix was done on 62 consecutive patients with a 1.5-T magnetic resonance imaging MRI unit. A bolus test with a power injector was used to calculate the optimal scan delay time. For quantitative evaluation, the signal-to-noise ratio (SNR) was measured in 3 regions of interest. Qualitative image analysis was evaluated independently by two radiologists and graded on a scale of 0–3. Separate analyses were done for the aorta and distal visceral arterial branches. Results The means SNR values were respectively 56.2 ± 15.2 (mean ± SD) for the aorta, 59.2 ± 15.1 for the celiac trunk, and 57 ± 15.2 for the superior mesenteric artery, with a homogeneous distribution ( P = .99). Consistent enhancement was confirmed by the lack of statistically significant differences between the SNR values. The average score for vessel visualization on source images ranged from good to excellent for different segments. After post-processing of images, the average score for distal arterial segments was significantly improved. The overall agreement between the 2 reviewers in the visualization of definite artery segments was excellent ( k = .91). Conclusion 3D CE-MRA with a 512-pixel base matrix and thin slices can be applied in a reproducible way with excellent depiction and delineation of small vessels. Such a protocol could be used routinely.

Resume Introduction Les syndromes de dedoublement medullaire (split cord malformation : SCM) se caracterisent par la division en deux parties de la moelle epiniere : les hemi-moelles peuvent etre, chacune dans un sac dural propre (SCM ou diastematomyelie de type I) ou bien etre dans un sac unique (SCM ou diastematomyelie de type II). Elles peuvent survenir de facon isolee ou s’associer plus volontiers a d’autres malformations medullaires, du squelette ou des teguments. Classiques chez l’enfant, leur decouverte chez l’adulte est beaucoup plus rare. Methode Nous rapportons les observations de deux femmes, de 40 et 54 ans, chez lesquelles fut revele un deboublement de la moelle epiniere de type II. Resultats La premiere patiente se plaignait de lombo-sciatalgies chroniques et de troubles imperieux mictionnels ; l’examen clinique decouvrit un syndrome radiculaire avec abolition du reflexe achilleen gauche ansi qu’une hyperpilositie lombaire. L’IRM mit en evidence une hernie discale L5/S1 exclue ainsi qu’un deboublement partiel de la moelle epiniere en regard de L3, associe a un spina bifida et une moelle attachee basse. La seconde patiente souffrait depuis 6 ans de lombalgies avec irradiation douloureuse perineale ; l’examen physique decouvrit un angiome cutane lombaire ; l’IRM revela un dedoublement medullaire dorsolombaire, de D12 a L1, associe a un spina bifida. Aucun eperon osseux ou fibreux fut mis en evidence dans les deux cas. En raison de l’absence de deficit moteur, aucune decision chirurgicale ne fut retenue. Conclusion Au travers de ces deux observations, nous proposons une revue de la litterature de 90 dossiers de diastematomyelie revelee a l’âge adulte.

International audience; Because radiation from flames is often the dominant mechanism for wildfire spread, detailed information on flame properties is required. The proposed procedure combines a spectrally resolved radiation model for simulating the line-of-sight infrared emission intensity and spectroscopy data and uses a genetic algorithm (GA) to determine a set of flame properties, allowing optimal agreement between model and outdoor experiments. GA calibration and sensitivity analysis were conducted using well-defined reference flames. The combined GA/radiation model was used with emission data to estimate the effective properties of flames from the combustion of woody fuel beds from 0.5 to 4 m in thickness. Experimental results show that the contribution of soot particles to flame emission increases with flame thickness. The GA was found to be robust and efficient in providing relevant flame properties from line-of-sight intensities on the infrared spectrum of radiation.

This paper presents the latest developments and validation results of a hybrid model which combines a broad-scale stochastic small-world network model with a macroscopic deterministic approach, to simulate the effects of large fires burning in heterogeneous landscapes. In the extended version of the model, vegetation is depicted as an amorphous network of combustible cells, and both radiation and convection from the flaming zone are considered in the preheating process of unburned cells. Examples are given to illustrate small-world effects and fire behavior near the percolation threshold. The model is applied to a Mediterranean fire that occurred in Corsica in 2009 showing a good agreement in terms of rate of spread, and area and shape of the burn. A study, based on a fractional factorial plan, is conducted to evaluate the influence of variations of model parameters on fire propagation.

International audience; As an alternative to the classical deterministic methods, a Monte Carlo method is proposed for the estimation of the radiant heat flux from wildland fires, and thus of fire-safe distances. The solid flame model is used, in which the flame is regarded as a uniformly-radiating surface with a simple geometry. Case studies are presented, ranging from the relatively simple case of planar or cylindrical flames to the case of the more complex geometries of irregular flame fronts where the strategy consists in approximating the front as a collection of individual solid flames. Model results are in good agreement with available data. An attempt is made to estimate the radiant heat flux ahead of a fire front spreading on a heterogeneous landscape. Finally the model is applied to determine the defensible space around a structure in which combustible vegetation has been totally cleared in the aim of reducing the wildfire threat to homes. (C) 2010 Elsevier Masson SAS. All rights reserved.

International audience; A series of outdoor experiments were conducted in a fire tunnel to measure the emission of infrared radiation from wildland flames, using a FTIR spectrometer combined with a multispectral camera. Flames of different sizes were produced by the combustion of vegetation sets close to wildland fuel beds, using wood shavings and kermes oak shrubs as fuels. The nongray radiation of the gas-soot mixture was clearly observed from the infrared emitted intensities. It was found that the flame resulting from the combustion of the 0.50 m long fuel bed, with a near-zero soot emission, may be considered as optically thin and that the increase in bed length, from 1 to 4 m, led to an increase in flame thickness, and therefore, in flame emission with contributions from both soot and gases. A further analysis of the emission was conducted in order to evaluate effective flame properties (i.e., emissivity, extinction coefficient, and temperature). The observation of emission spectra suggests thermal nonequilibrium between soot particles and gas species that can be attributed to the presence of relatively cold soot and hot gases within the flame.

This paper presents the development and validation results of a weighted small-world network model designed to simulate fire patterns in real heterogeneous landscapes. Fire spread is simulated on a gridded landscape, a mosaic in which each cell represents an area of the land surface. In this model, the interaction between burning and non-burning cells (here, due to flame radiation) may extend well beyond nearest neighbors, and depends on local conditions of wind, topography, and vegetation. An approach based on the coupling of the solid flame model with the Monte Carlo method is used to predict the radiative heat flux from the flame generated by the burning of each combustible cell to its neighbors. The weighting procedure takes into account latency (a combustible cell will only ignite when it has accumulated enough energy along time) and flaming persistence of burning cells. The model is applied to very different fire scenarios: a historical Mediterranean fire that occurred in southeastern France in 2005 and experimental fires conducted in arid savanna fuels in South Africa in 1992. Model results are found to be in agreement with real fire patterns, in terms both of rate of spread, and of the area and shape of the burn. This work also shows that the fractal properties of fire patterns predicted by the model are similar to those observed from satellite images of three other Mediterranean fire scars.

Split cord malformation (SCM) is an uncommon developmental anomaly characterized a cleft spinal cord. In type I, each of the hemicords is contained within an individual dural tube whereas in type II there is a common dural tube housing both hemicords. Commonly diagnosed in childhood, adult presentation is exceptional.We report the case of two women whose type II SCM was discovered at the age of 40 and 54 years.The first patient complained of chronic lombar and radicular chronic pain with dysuria. Physical examination revealed a radicular syndrome with abolition of the left Achille reflex and a lombar hair tuft. MRI showed a disc herniation at the L5-S1 level, with a partial SCM at the level of the L2 vertebra, spina bifida and tethered cord. The second patient complained of lombar pain with perineal irradiation for 6 years. Physical examination showed a lombar cutaneous angioma. MRI revealed a thoraco-lombar SCM at the T12 to L1 level, with spina bifida. No spur could not be identified in either patient. No further surgical treatment was given.Based on these two observations, we propose a review of literature reporting 90 cases of adult SCM.

Background The purpose of this prospective study was to assess the value of contrast-enhanced magnetic resonance cholangiography with mangafodipir trisodium perfusion for detection and localization of trauma-induced and postoperative bile duct leaks. Methods Eleven patients with suspected bile duct leaks after trauma (n=5) or surgery (n=6) were included. Patients with suspected leaks after cholecystectomy were excluded. All patients underwent contrast-enhanced magnetic resonance cholangiography with two-dimensional axial and three-dimensional coronal gradient-echo images acquired 1 to 3 hours after intravenous administration of mangafodipir trisodium perfusion. Contrast-enhanced magnetic resonance cholangiography findings were correlated with direct cholangiography obtained in all patients, including endoscopic retrograde (n=7) and percutaneous transhepatic cholangiography (n=4). Results Biliary tract enhancement was identified in all patients on contrast-enhanced magnetic resonance cholangiography. Peritoneal cavity fluid and bile collections that contained extravasated mangafodipir trisodium (increased signal intensity on gradient-echo sequences) were demonstrated in 6 patients. Direct cholangiography confirmed the presence of bile duct leaks in these 6 patients and the absence of bile duct leaks in 5 patients. There was no false-negative or false-positive contrast-enhanced magnetic resonance cholangiography. Conclusions Mangafodipir-enhanced magnetic resonance cholangiography is a noninvasive technique that can provide functional biliary information with excellent depiction of bile duct leaks.

The authors report two uncommon cases of incidental superior mesenteric vein aneurysm in two asymptomatic women. Patients underwent ultrasonography, CT and MR angiography. The etiology, clinical features and treatment are discussed along with a review of to the literature.

To evaluate the correlation between computed tomography (CT) and surgery, for the diagnosis of bezoar in small bowel obstruction. To analyze the predisposing etiologic factors in this population.We reviewed retrospectively between 1994 and 1999, 12 patients whose final diagnosis was small bowel obstruction with bezoar. All patients underwent helical CT scan before treatment. Eight patients were treated by surgery and 4 recovered with gastric aspiration.Small bowel obstruction was diagnosed by CT which always demonstrated a transition zone with ovoid intraluminal mass outlined by the bowel wall. The mass consisted of a mixture of soft tissue and internal gas bubbles like feces, suggesting bezoar. Surgery confirmed small bowel obstruction and presence of bezoar. Predisposing factors were: partial gastrectomy (2/12), post surgical adhesions (7/12), Meckel diverticulum (1/12) and dietary factors.We agree with the authors of the few prior CT reports and suggest that the characteristic CT appearance of mottled gas pattern is pathognomonic of bezoar with an excellent correlation in our population.

International audience; Excavated from 2003 to 2011, the site of Beg ar Loued in the southern part of Molène Island has yielded the remains of two dry stone houses superimposed and occupied between 2150 and 1750 cal BC. At this time, the Molène Archipelago was in a similar form as today, except the foreshores, which were much larger. The site was then a hundred meters from the shoreline. The study of the site allows a more comprehensive understanding of the way of life of this island society. They used to farm and breed livestock, supplemented by fishing on the foreshore, collecting limpets and to a lesser extent hunting migratory birds. The material culture shows that this group used local resources: clay, sea pebbles and outcrops. This picture of a self-sufficient society must be qualified. Indeed, the architecture of buildings, the ceramic forms, the lithic technology and the metalworking are evidence that this society was linked with what was happening on the mainland. That raises question of seafaring and the nature of the links between this island society and the continent.; Fouillé de 2003 à 2011, le site de Beg ar Loued au sud de l’île de Molène a livré les vestiges de deux maisons en pierres sèches superposées et occupées de 2150 à 1750 cal. BC. À cette période, le plateau Molénais, déjà insulaire depuis le Néolithique ancien, se présentait dans une forme assez proche de l’actuel, exception faite des estrans qui étaient beaucoup plus vastes. Le site se trouvait alors à une centaine de mètres du trait de côte. L’étude du site a permis de mieux comprendre le mode de vie de cette com-munauté insulaire. Celle-ci pratiquait l’agriculture et l’élevage, complétés par la pêche sur estran, la collecte des patelles et, dans une moindre mesure, la chasse aux oiseaux migrateurs. La culture matérielle montre que ce groupe exploitait les ressources locales : argile, cordons de galets et affleurements rocheux. Ce tableau d’une société autarcique se doit pourtant d’être nuancé, car l’architecture des bâtiments, les formes céramiques, la technologie lithique et la métallurgie sont autant d’indices montrant que cette société n’était pas à l’écart des circuits d’échange et qu’elle était en phase avec les changements et les innovations culturels identifiés sur le proche conti-nent. Dès lors, se pose la question de la navigation et de la nature des liens qu’entretenait cette communauté insulaire avec le continent.