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During the two last decades, medical imaging showed considerable changes in technology and in knowledge of abdominal diseases. This review illustrates the consequences of this evolution on the prescription of a radiological examination for a gastroenterological patient, in 15 selected and illustrative topics.L’imagerie radiologique a connu des développements considérables au cours des deux dernières décennies. Ces nouveaux développements modifient la prescription raisonnée et raisonnable en imagerie médicale en pathologie gastrointestinale. Cet article de revue il lustre ces changements en 15 tableaux représentatifs de cette évolution.

Coastal marine systems are currently subject to a variety of anthropogenic and climate-change-induced pressures. An important challenge is to predict how marine sediment communities and benthic biogeochemical cycling will be affected by these ongoing changes. To this end, it is of paramount importance to first better understand the natural variability in coastal benthic biogeochemical cycling and how this is influenced by local environmental conditions and faunal biodiversity. Here, we studied sedimentary biogeochemical cycling at ten coastal stations in the Southern North Sea on a monthly basis from February to October 2011. We explored the spatio-temporal variability in oxygen consumption, dissolved inorganic nitrogen and alkalinity fluxes, and estimated rates of nitrification and denitrification from a mass budget. In a next step, we statistically modeled their relation with environmental variables and structural and functional macrobenthic community characteristics. Our results show that the cohesive, muddy sediments were poor in functional macrobenthic diversity and displayed intermediate oxygen consumption rates, but the highest ammonium effluxes. These muddy sites also showed an elevated alkalinity release from the sediment, which can be explained by the elevated rate of anaerobic processes taking place. Fine sandy sediments were rich in functional macrobenthic diversity and had the maximum oxygen consumption and estimated denitrification rates. Permeable sediments were also poor in macrobenthic functional diversity and showed the lowest oxygen consumption rates and only small fluxes of ammonium and alkalinity. Macrobenthic functional biodiversity as estimated from bioturbation potential appeared a better variable than macrobenthic density in explaining oxygen consumption, ammonium and alkalinity fluxes, and estimated denitrification. However, this importance of functional biodiversity was manifested particularly in fine sandy sediments, to a lesser account in permeable sediments, but not in muddy sediments. The strong relationship between macrobenthic functional biodiversity and biogeochemical cycling in fine sandy sediments implies that a future loss of macrobenthic functional diversity will have important repercussions for benthic ecosystem functioning.

The present study investigates correlations between abundances of nematodes (at the genus level) and benthic microalgae on an intertidal mudflat in the Westerschelde Estuary (south-west Netherlands), using both multi- and univariate methods. Two sample series, covering surface areas of 10 cm2 (meioscale) and 1.25 cm2 (microscale) per sample were analysed. Trophic type analysis indicated that an average of 31% of the nematode community were candidate grazers of microalgae. Multivariate data analysis indicated that only a limited part of the variation in the nematode data could be explained in relation to pigments. Total nematodes did not show any correlation with the pigment data. On the meioscale, the genera Tripyloides and Calyptronema correlated negatively with chlorophyll concentration (chl-a and chl-c, respectively), while Prochromadorella correlated positively with the ratio of fucoxanthin to chl-a, a ratio which at the present sampling site can be considered to be a measure of the proportion of diatoms in the total microalgal standing stock. On the microscale, up to ten genera, comprising 76% of total nematode numbers, were correlated with pigments. A majority (74%) correlated specifically with the ratio of fucoxanthin to chl-a, while much fewer nematodes showed a direct correlation to pigment concentrations. Whereas many of these correlations could be explained in terms of direct trophic links, several others probably represented indirect relationships, trophic or other. Food densities may be less important structuring factors of nematode communities on tidal flats than relative abundances of particular food sources. It is suggested that nematodes actively migrate towards ‘optimal’ food patches, and that this dynamic aspect of nematode–microalgae correlations is best revealed at a spatial-scale small enough to allow a rapid response of nematodes to changes in adjacent patches. Apparently, the microscale used in the present study is more adequate for the study of such intricate interactions than the meioscale.

Self-treatment of chronic headache with suppositories containing paracetamol and acetylsalaicylic acid may lead to serious complications. We report the radiological features of five cases of rectal stenosis following the use of such suppositories. The role of the double-contrast barium enema in suggesting the diagnosis of this complication of a chronic and often unrecognized self-treatment is emphasized.

Background In adhesive small bowel obstruction, the early recognition of complications such as strangulation or volvulus is essential to choose between surgical or conservative initial treatment. The objective of this study was to determine prospectively the contribution of computed tomography (CT) to decision making in the management of these patients. Methods Patients with suspected adhesive small bowel obstruction had CT at admission. Patients with CT signs of volvulus or strangulation and/or clinical signs of peritoneal irritation underwent urgent surgery; other patients had conservative initial treatment. Results Fifty-four patients were evaluated. CT demonstrated signs of strangulation or volvulus in 19 patients, including three with signs of peritoneal irritation. Within this group, urgent laparotomy was performed in 17 patients and confirmed the CT diagnosis in 16. Thirty-seven patients without clinical or CT signs of complications had initial conservative treatment; among them, seven of 12 with a distal obstruction determined by CT required a delayed operation for persisting obstruction, compared with two of 25 patients with a proximal obstruction (P Conclusion CT is useful for the evaluation of adhesive small bowel obstruction, to detect accurately patients with complications who require urgent operation and to determine the location of the adhesion, which represents a significant prognostic factor for success of conservative treatment.

The metazoan meiobenthos was investigated in an Antarctic coastal sediment (Factory Cove, Signy Island, Antarctica). The fine sands contained much higher abundances compared to major sublittoral sediments worldwide. Classified second after Narrangansett Bay (North Atlantic) they reached numbers of 13 × 106ind m-2. The meiofauna was highly abundant in the surface layers, but densities decreased sharply below 2 cm. Vertical profiles mirrored steep gradients of microbiota, chloropigments and organic matter and were coincident with chemical stratification. Spatial patchiness manifested especially in the surface layer. Nematodes dominated (up to 90%), andAponema, Chromctdorita, Diplolaimella, Daptonema, MicrolaimusandNeochromadoraconstituted almost the entire community. Overall, the nematode fauna showed a strong similarity with fine sand communities elsewhere. The dominant trophic strategies were epistrarum and non-selective deposit feeding, but the applied classification for feeding guild structure of the nematodes of Factory Cove is discussed. High standing stock, low diversity and shallow depth distribution may have occurred because of the high nutritive (chlorophyll exceeded lOOOmgm-2and constituted almost 50% of the organic pool) and reductive character of the benthic environment. These observations must have originated from the substantial input of fresh organic matter from phytoplankton and microphytobenthic production, typical for an Antarctic coastal ecosystem during the austral summer.

Partial nephrectomy and tumour enucleation are increasingly accepted as an organ sparing approach for small renal cell carcinomas. Repeated computed tomography or sonography for the early detection of tumour recurrence are mandatory during the follow-up. We report two cases of renal pseudotumour mimicking a tumour recurrence: one case is related to the pseudotumoral appearance on sonography of a tumour defect rilled by a fatty flap, and the other to the relative migration of an accessory spleen into the site of the cuneiform nephrectomy. The recognition of renal pseudotumours following partial nephrectomy prevents confusion with tumour recurrence on follow-up examinations. Partial nephrectomy and tumour enucleation are increasingly accepted as an organ-sparing approach for small renal cell carcinomas. Repeated radiological examinations are recommended for follow-up. However, this conservative approach has led to imaging appearances that can cause confusion. The pressure to detect an early recurrence increases the risk of misinterpreting a renal pseudotumour. We report two examples of renal pseudotumours that mimic tumour recurrence following partial nephrectomy. Case reports Case 1 A 42-year-old woman, with a previous history of right radical nephrectomy for a renal cell carcinoma 12 years previously, underwent enucleation of a second renal cell carcinoma which measured 29x24x2 2 mm and was located in the upper pole of the left kidney. This tumour was completely resected. The first sonographic followup examination was performed 6 months later and snowed a 17x15 mm hyperechoic mass in the upper pole of the left kidney. The mass was slightly heterogeneous and was associated with posterior acoustic shadowing. It was separated from the adjacent normal

The metazoan meiofauna of nine stations in shelf break and upper slope areas (70 to 1500 m water depth) of the N.E. Atlantic were investigated in order to assess which environmental factors are important in the control of densities and sediment profiles. Total meiofaunal densities (ranging between 368 and 1523 ind/10 cm 2 ) were correlated with bacterial densities, an important food source for meiofauna. However, considering sediment vertical distribution profiles, the relative importance of both food and oxygen on the meiofauna became obvious. A combination of both bacterial densities and oxygen supply could explain about 95 % of the variability in the vertical profiles of the meiofauna densities. Meiofauna numbers increase in proportion to food availability in the surface sediment layers, but this relationship breaks down in deeper sediment layers where the oxygen supply is often limiting, particularly in fine sediments.

The meiobenthic fauna of the Westerschelde, a highly polluted and physically disturbed estuary in the south-west Netherlands, was investigated. Samples were taken in spring from six transects, including the intertidal, subtidal and channel area, and located along the salinity gradient. The samples were subdivided into slices to examine the vertical distribution of meiobenthos. Meiobenthos densities were higher in the intertidal than in most permanently submersed areas; the subtidal sites below 7 salinity were nearly devoid of meiobenthic life. Nematodes were by far the most abundant meiobenthic organisms in the intertidal, but were less dominant in the other areas. Gastrotrichs, turbellarians, copepods and large ciliates were usually more numerous in the subtidal and channels compared to the intertidal, both in relative and absolute terms. Vertical distribution of the meiobenthos was rather heterogeneous. Most intertidal stations exhibited a subsurface density peak, whereas in the subtidal and channel area, both subsurface and surface maxima were found. The nematode fauna was examined in more detail and the distributional characteristics of the most important species, with respect to salinity, grain size, water depth and sediment depth were reported. The majority of species had their centre of distribution in the intertidal, although some extended substantially into the subtidal zone. Only a few species had a predominantly subtidal distribution. Most nematode species penetrated relatively deep into the sediment and only some species were real surface dwellers. The nematode diversity per unit of surface reflected more or less the density differences and was higher in the intertidal than in the subtidal sites within a comparable salinity regime. When expressed per common number of individuals, however, there were no differences in diversity in the different areas. Canonical correspondence analysis showed sediment depth to be as important as water depth, salinity or sedimentary characteristics in the determination of community structure. Intertidal communities exhibited a well-developed community gradient with depth into the sediment, whereas the vertical structure of subtidal and channel stations was different from the intertidal zonation and in some cases showed a distorted pattern. This was probably caused by sediment disturbance due to higher current velocities and dredging activities in these regions. It is argued that, although at some subtidal sites a characteristic subtidal nematode population may persist, in many cases the sublittoral of the Westerschelde is either too dynamic an environment or food availability is too low to meet requirements for growth and reproduction of the nematodes. The populations are probably not self-sustaining but persist due to continuous replenishment from less harsh areas by means of the estuarine circulation.

The importance of different functional traits of macrobenthos in benthic processes of the Southern Bight of the North Sea was investigated to estimate the effects of density declines and species loss on benthic ecosystem functioning. Two laboratory experiments were performed: before (winter, temperature = 10°C) and after (summer, temperature = 18°C) sedimentation of the spring phytoplankton bloom. Single species treatments of key species (Abra alba, Lanice conchilega and Nephtys sp.) with different functional traits were added to microcosms at 3 density levels (natural, lower, lowest) to account for possible density declines. Sediment–water exchanges of oxygen and nutrients, denitrification and bioturbation were measured. In absence of fauna, benthic mineralisation in the summer experiment was 2.0 times higher than in winter. Fauna stimulated microbial respiration more in summer (up to 100% in L. conchilega treatments) than in winter (negligible fauna effect). As chlorophyll a concentrations were similar in both seasons, the stronger fluxes in summer must be explained by a higher macrobenthic activity owing to the elevated temperature and better condition of the animals. Stimulation of mineralisation by the 3 species in the microcosms was different, and behaviour-related. Owing to its irrigation activity, the tube dweller L. conchilega had more pronounced influences on benthic respiration, nutrient release and denitrification than did the biodiffusers, A. alba and Nephtys sp. A. alba appeared to be a more effective bioturbator than Nephtys sp. Processes such as benthic respiration, nutrient fluxes, denitrification and bioturbation seem to be related to animal densities and therefore decreases in densities can possibly have implications for ecosystem functioning.

A cyst of the gallbladder is a very rare lesion. The possible causes of such an anomaly are reviewed. It may be acquired or congenital. The latter is particularly exceptional. A case of congenital cyst is reported and illustrated by various imaging techniques.

We investigated meiobenthic community response (as density and vertical distribution) to the sedimentation of phytoplankton in 2 contrasting sites in the southern North Sea, one with fine grained sediment close to the coastline and another with highly permeable sediments. Meiobenthic densities and pigments in the water column and sediment were measured monthly from October 2002 until October 2003. Stable isotope 13C and 15N signatures were analysed in sediment particulate organic matter (POM), water suspended particulate matter (SPM) and in different meiobenthic taxa at 3 different times (prior, during and after spring bloom deposition) at 2 sediment depths (0 to 1 and 4 to 5 cm). Our aim was to determine whether sediment type affects the overall meiobenthic community response (densities and vertical distribution) and utilisation of freshly deposited phytoplankton as a food source. Variation in nematode response to the sedimentation event was evident and was related to the contrasting biogeochemical processes at the stations. In permeable sediments, the nematode response was rapid after phytoplankton deposition, while in the fine-grained station, nematode response (as density) was delayed. In general, meiobenthic 13C signatures remained relatively constant over time and were not coupled with changes in water SPM and sediment POM. There was vertical variation in meiobenthic 13C signatures in fine sediments. Nematodes belonging to the genera Sabatieria and Richtersia from the deeper sediment layer had isotope signatures similar to those of surface living nematodes, indicating migration of these genera to the surface to feed. In permeable sediments, such vertical differences were absent because of sediment biogeochemical properties. ?13C and ?15N values of copepods clearly indicated a chemoautotrophic food source within the fine-grained sediment, which has not been previously reported for these environments.

The response of benthic bacterial community composition, diversity, and biomass to phytoplankton deposition was investigated in 2 different sediment horizons at 2 contrasting sites in the southern North Sea. Differences in bacterial community composition between stations were observed. Seasonal differences in bacterial community composition were significant and were stronger in fine sediments, probably related to stronger fluctuations in food availability. Variation in community composition over the vertical sediment profile was different for both stations. In coarser sediment, the difference was mostly due to the absence of certain operational taxonomic units (OTUs) at the surface, while in fine sediment, 2 distinct communities were present. A RELATE test revealed that bacterial community composition was influenced by the amount of labile organic matter (estimated through chl a concentration in the sediment). Diversity in terms of OTU richness and Shannon-Weaver diversity index was higher in finer grained sediments. In coarser sediments, diversity at the surface layer was lower, which might be related to stronger hydrodynamic pressure at this station. These differences were not observed at the other station. Seasonal changes in diversity were not detected at either station. Bacterial biomass was slightly higher in finer sediments and was not correlated with either chl a or temperature. Seasonal differences in bacterial biomass followed those observed for community composition, while no vertical differences were detected.

A 36-year-old man living in Algeria developed abdominal pain, asthenia, jaundice, and vomiting. He had no medical or surgical history. Laboratory tests revealed anemia, leukopenia, cytolysis, cholestasis and hyperbilirubinemia. Gastroscopy showed esophageal varices and duodenal cap ulcerations suggestive of portal hypertension. Abdominal sonography displayed a thickening of the common bile duct, splenomegaly and absence of gallbladder stones. Two months later, the patient was admitted in our institution for progressive asthenia. A contrast enhanced CT scan was performed, showing a tubular soft-tissue enhancing mass extending from the porta hepatitis to the head of the pancreas within the hepato-duodenal ligament. Intra and extrahepatic bile ducts were not dilated. The main portal vein and the intrahepatic branches of the portal vein appeared normal on axial CT scans. An additional ultrasound was performed, showing a non-dilated common bile duct (arrow Fig. A) with a marked thickening of the common bile duct wall and small serpiginous vessels within the thickening either in power Doppler as in color Doppler (arrowheads Figs. B and C). Additionally, a short and thigh narrowing of the main portal vein proximally to the portal division was disclosed, and secondarily confirmed on the multiplanar reformations of the contrast enhanced CT scan. A medullary biopsy was performed in the context of bicytopenia and splenomegaly and showed myelofibrosis.

A 32 year-old man presented with sinusitis, proteinuria, mononeuritis multiplex, very increased acute phase proteins. Anti-PR3 ANCA were detected and Wegener's granulomatosis (WG) was diagnosed. As abdominal tomodensitometry detected a tumoral process of the left kidney, a paraneoplastic vasculitis associated with a renal cancer was suspected. Biopsy of the mass showed fibrosis, inflammatory infiltrates and necrotizing granulomas. No malignant cells were detected. The outcome was favourable after administration of methylprednisolone and cyclophosphamide. Characteristics of the nine previously reported renal inflammatory pseudotumors associated with WG are discussed.

We report the case of a 43-year-old woman with primary Sjogren's syndrome, according to Americano-European criteria. Eighteen months after the diagnosis, the patient presented pneumatosis cystoides coli (PCC), which resolved with medical treatment consisting of diet and cisapride. Four years after this episode, the patient has not developed clinical features of another systemic inflammatory rheumatic disease and PCC has not relapsed. To the best of our knowledge, the association between primary Sjogren' syndrome and PCC has never been reported. Physiopathology and treatment of PCC are discussed.

In the Schelde continuum, a succession in the phytoplankton community is observed along the transition from the river to the freshwater tidal reaches of the estuary and from the freshwater to brackish reaches of the estuary. The goal of this study was to experimentally evaluate the contribution of changes in salinity and light climate to this succession. In summer 2000 and in spring 2001, phytoplankton communities from the river, the freshwater tidal reaches and the brackish reaches of the estuary were incubated under high or low light intensities and exposed to a change in salinity. HPLC analysis was used to evaluate the response of different algal groups to changes in light intensity and salinity. When incubated at a light intensity corresponding to the mean underwater light intensity of the freshwater tidal reaches, growth of phytoplankton from the river as well as from freshwater tidal reaches was significantly lower than when incubated at a light intensity corresponding to the mean underwater light intensity of the river. The phytoplankton community from the freshwater tidal reaches did not appear to be better adapted to low light intensities than the phytoplankton community from the river. Although diatoms were expected to be less sensitive to a reduction in light intensity than green algae, the opposite response was observed. Freshwater and brackish water phytoplankton were negatively affected by respectively an increase or decrease in salinity. However, the effect of salinity was not strong enough to explain the disappearance of freshwater and brackish water phytoplankton between a salinity of 0.5 and 10 psu, suggesting that other factors also play a role. In the freshwater phytoplankton communities from the river and the freshwater tidal reaches, green algae and diatoms responded in a similar way to an increase in salinity. In the brackish water phytoplankton community, fucoxanthin displayed a different response to salinity than lutein and chlorophyll a.

To report a new CT sign of small bowel strangulation. Two cases of small bowel obstruction evaluated by spiral CT with intravenous contrast injection. In both cases we observed an absence of parietal enhancement of the diseased bowel loop, visible on early scans only. This feature was accompanied by signs of bowel obstruction. The two patients had a segment of necrotic ileum resected. Delayed enhancement of a bowel loop in cases of small bowel obstruction should suggest the diagnosis of strangulation and lead to rapid surgical treatment. 8 refs., 2 figs.

Surgery remains the only potentially curative treatment for liver metastases. After margin free resection, approximately 30% of the patients present long-term survival. Due to the metastases number and/or volume, only 10 to 15% of the patients are candidates for curative-intent surgery. Thus, the objectives of the diagnostic and therapeutic management are to select adequately the patients for surgery and to improve resection rate by the use of neoadjuvants methods. Positron emission tomography could improve the preoperative detection of hepatic and extrahepatic metastases leading to the exclusion of some patients from useless surgical exploration. For patients with initially resectable tumors, no benefit has been demonstrated for adjuvant chemotherapy. For non resectable metastases, two neoadjuvants methods should be evaluated, chemotherapy to reduce tumor volume and portal vein embolization of the tumor side to improve the hepatic functional reserve and allow larger resection. For non-accessible lesion, selective tumor destruction using radiofrequency offers promising perspectives. In conclusion, the multiplication of the diagnostic and therapeutic methods certainly improve the global management of patients with liver metastases but also makes more difficult the individual choice for the best treatment. For this reason, a multimodal approach is absolutely mandatory.

The great morbidity and mortality associated with pseudoaneurysms complicating pancreatic pseudocysts stress the need for their early detection. The authors report the use of colour Doppler sonography in the detection of pseudoaneurysms within pancreatic pseudocysts, emphasizing not only the value of this modality in the initial diagnosis, but also its value in monitoring the success of transcatheter embolization. Colour Doppler should be used systematically in the evaluation of pancreatic pseudocysts.

Hepatocellular adenoma resection and focal nodular hyperplasia supervision are widely recognized as the best management when these benign liver tumors are diagnosed. Differential diagnosis is thus mandatory.Twenty-nine patients with a presumed benign liver tumor were retrospectively analyzed.Histopathological analysis of these resected liver tumors demonstrated hepatocellular adenoma in 16 patients and focal nodular hyperplasia in 13. One hepatocellular carcinoma was disclosed into a hepatocellular adenoma and 2 hepatocellular adenoma showed foci of liver-cell dysplasia. Seven patients with hepatocellular adenoma (43%) had evidence of intratumoral hemorrhage, among which 3 patients were admitted with intraperitoneal tumoral rupture. Computed tomography, performed in 26 patients, was the most reliable examination to characterize these presumed benign liver tumors. Magnetic resonance imaging concerned only 5 patients but 3 hepatocellular adenoma and 1 focal nodular hyperplasia were diagnosed. The indications of focal nodular hyperplasia surgical resection were chronic pain (4 pts), hepatocellular adenoma diagnosis (4 pts), undeterminate liver mass (2 pts), a liver mass of unknown origin in patients with a neoplastic history (3 pts). A diagnosis of focal nodular hyperplasia assumed by the imaging work-up was always histologically confirmed. All the patients underwent hepatic resection with no mortality.This report underlines the risk of hemorrhage or malignant transformation of hepatocellular adenoma that justifies a safety surgical resection. An imaging work-up in favor of focal nodular hyperplasia allows radiological observation.

We report a case of radiation-induced hepatic injury as a complication of localized abdominal radiotherapy for epidural spread of non-Hodgkin's lymphoma. The liver was evaluated by triphasic contrast enhanced helical CT scan. Hepatic biopsy demonstrated changes typical of veno-occlusive disease. The pattern of hepatic enhancement resulting from the radiation-induced veno-occlusive process is discussed.

Fine-needle aspiration biopsy (FNAB) is safe, inexpensive, minimally invasive, and highly accurate in the diagnosis of nodular diseases of the thyroid. However, FNAB does not provide a reliable benign versus malignant diagnosis for 100% of the cases analysed. It is possible to increase the accuracy of the cytological diagnosis by means of information contributed by different clinical variables. In the present study we evaluate the diagnostic value of 10 variables in addition to FNAB on a series of 218 specimens for which we obtained histological diagnoses including 37 cancers (17%). The diagnostic information contributed by these variables was analyzed by means of the Decision Tree technique, an artificial intelligence-related method which forms part of the Supervised Learning algorithms. The results show that Decision Trees enable some subpopulations of patients with uncertain FNAB results to be characterized.

We report a case of blunt traumatic right diaphragm rupture with hepatic hernia. The diagnosis was first suggested by an abnormal hepatic location depicted on axial CT. This finding can be considered as a potentially new indirect sign of right diaphragm rupture in patients with blunt trauma. The diagnosis was then confirmed by reformatted CT and MR images.

Objectifs Les auteurs comparent l’index de severite de la pancreatite aigue (PA) obtenu a partir de l’analyse des criteres morphologiques scanographiques de la classification de Balthazar et de la classification de Mortele. Materiels et methodes Prospectivement le scanner abdominal multiphasique avec injection de produit de contraste iode chez 94 patients presentant des signes cliniques et biologiques de PA ont ete analyses selon la classification de Balthazar et de Mortele. La methode a ete repetee dans les PA graves et lors des complications. Resultats Parmi les PA (n = 67), l’analyse selon l’index de severite (CTSI) de Balthazar retrouve 37 PA legeres, 24 PA moderees 6 PA severes. L’analyse selon le CTSI de Mortele retrouve 37 PA legeres, 21 PA moderees et 9 PA severes. Conclusion Le CTSI de Mortele tient compte des complications, il est plus reproductible pour les auteurs alors que le CTSI de Balthazar d’utilisation courante est plus limite dans la stadification des complications.

We report our prospective study evaluating biphasic helical CT of the aorta after endoluminal stent-graft placement.Biphasic helical CT scans in 95 patients with abdominal and thoracic aortic aneurysms who had undergone endoluminal stent-graft placement were reviewed. After a test bolus injection of 15 ml of contrast media at a rate of 3.5 ml/sec for the measurement of the optimal start delay, the aorta was scanned using the following parameters: collimation of 5 mm, table speed of 7 mm per rotation, tube rotation time of 0.75 sec, 120 kV, and 295 mA. A delayed helical CT scan was obtained 15 sec after the initial acquisition using the same parameters.Biphasic helical CT scans showed perigraft leakage in 45 (47%) of 95 patients. Leakage was shown only on arterial phase CT in eight patients and only on the delayed scans in three patients. In two patients, leakage shown on the delayed acquisition was retrospectively seen on the first scan. Leakage and outflow vessels were most visible on the arterial phase acquisition in 17 patients and on the second acquisition in six patients. Overall, biphasic acquisition was superior to arterial phase acquisition alone in 15 (16%) of 95 patients.The diagnostic value of biphasic helical CT is superior to arterial phase acquisition alone for the evaluation of the aorta after endoluminal stent-graft therapy.

Intraductal papillary-mucinous tumor of the pancreas (IPMT) is an uncommon entity, defined as an intraductal papillary proliferation of mucin-producing epithelial cells. Since the original description of the disease by Ohhashi in 1982, the definition and the classification of the disease has remained confused until the recently published classification of the World Health Organisation (WHO). The purpose of this article is therefore to report the clinico-pathological features of IPMT according to the WHO classification, to illustrate the radiological features especially the computed tomographic signs and to discute of the treatment.

BACKGROUND: A study was undertaken to evaluate the reliability of a digital tracheal sound analyser (ELENS-DSA) in predicting nocturnal changes in airways resistance in asthmatic patients. This device allows continuous measurement of the proportion of the time occupied by wheezing (Wh%). METHODS: Nocturnal polygraphic studies with simultaneous continuous monitoring of tracheal sounds and airways resistance were performed in seven patients with nocturnal asthma. In order to evaluate the possible bias in wheezing estimation, each tracheal sound recording was passed through the automatic analyser and simultaneously monitored with earphones by an experienced observer. RESULTS: The device detected audible wheezing with an optimal sensitivity and specificity of 70%. Snoring was a minor cause of the relatively poor characteristics of the system. A close correlation (p < 0.001) between Wh% and airways resistance was observed only in those patients with the highest increase in resistance; when the results of all the subjects were pooled the correlation observed was poor. The predictive value of Wh% in detecting changes in airways resistance during 10 minute intervals was lower than 70%. The positive and negative predictive values of Wh% were raised to 79% and 83%, respectively, for 30 minute intervals. CONCLUSIONS: The ELENS-DSA system is a relatively crude means of detecting wheezing and assessing bronchoconstriction quantitatively. However, it is able to detect accurately nocturnal bronchoconstriction for 30 minute intervals. This finding, along with the fact that the monitoring is non-invasive, suggests that it may be a promising tool, especially for patients during sleep.

Partial nephrectomy and tumour enucleation are increasingly accepted as an organ sparing approach for small renal cell carcinomas. Repeated computed tomography or sonography for the early detection of tumour recurrence are mandatory during the follow-up. We report two cases of renal pseudotumour mimicking a tumour recurrence: one case is related to the pseudotumoral appearance on sonography of a tumour defect filled by a fatty flap, and the other to the relative migration of an accessory spleen into the site of the cuneiform nephrectomy. The recognition of renal pseudotumours following partial nephrectomy prevents confusion with tumour recurrence on follow-up examinations.

Twelve sites around Gazi Bay, Kenya, were examined for macrobenthic infauna. Stations differed in human disturbance, vegetation, and sediment type (sandflat, beach, denuded and virgin mangrove sites, with Sonneratia, Rhizophora, Avicennia, Ceriops or Bruguiera vegetation). Sixteen higher taxa were counted; Isopoda, Amphipoda, Polychaeta, Cumacea and Tanaidacea were determined to family level (sometimes to genus or species). Total densities of infauna ranged from 265 to 6025 ind m-2. Gazi mangals had higher macrobenthos densities than other mangrove sediments described in literature and than the Gazi sandflats. The densities found in Gazi sandflats were comparable to similar habitats elsewhere. Virgin mangrove sediments were rich in mud and organic material, and were characterized by high densities of macro-Oligochaeta and Mollusca. Sandflats, beaches, exploited (denuded) and less dense mangroves or mangroves higher in the tidal zone (Bruguiera) were much more sandy and had a high abundance of Polychaeta and Nemertini. Structural patterns in the macrobenthos were only vaguely associated with vegetation type. Human impact (cutting) has resulted in a drastic decrease in densities of macro-infauna, possibly related to a reduction of organic material in the sediment.

The great morbidity and mortality associated with pseudoaneurysms complicating pancreatic pseudocysts stress the need for their early detection. The authors report the use of colour Doppler sonography in the detection of pseudoaneurysms within pancreatic pseudocysts, emphasizing not only the value of this modality in the initial diagnosis, but also its value in monitoring the success of transcatheter embolization. Colour Doppler should be used systematically in the evaluation of pancreatic pseudocysts.

Variceal bleeding carries high early mortality, especially after failure of conventional treatments such as endoscopic injection therapy. The present study analyses the efficacy of transjugular intrahepatic portosystemic stent shunt (TIPS) in cirrhotic patients after failure of sclerotherapy for variceal bleeding.Twenty-four consecutive patients underwent TIPS in this indication.The procedure was successful in all patients, with reduction of size or disappearance of varices in 96% of them. Four patients (17%) developed encephalopathy and six (25%) rebled during the follow-up period (median 5 months; range 1-19). Thirty-day mortality was only 17% and 29% during the follow-up period. Deaths were mainly due to liver failure, especially after procedures performed in emergency. Significant decrease in liver function was observed in the days following the procedure. To maintain long-term patency of the shunt, revision was required in nine patients (38%).TIPS seems to be a promising salvage therapeutic procedure after failed sclerotherapy, but this needs to be addressed in controlled trials.

Because of its availability, ultrasound should be the preferred initial modality for the evaluation of palpable superficial masses. Most ultrasound units are equipped with high frequency probes that allow superficial focalization. The differential diagnosis of soft tissue masses and the sonographic features of some benign and malignant soft tissue lesions are reviewed in this article. After an initial ultrasound evaluation confirming the presence of a tumor, the need for and the role of other imaging modalities can be determined. In selected cases ultrasound may obviate the need for further imaging. MRI and CT should be reserved for cases in which sonography fails to establish a specific diagnosis or to demonstrate the limits of the soft tissue mass.

The authors report the fortuitous demonstration of an asymptomatic gossypiboma during the preoperative staging of a rectal carcinoma 13 years after abdominal surgery for perforated gastric ulcer. Ultrasonography disclosed a well-defined hypoechoic mass containing highly echogenic foci with a strong posterior shadow. The CT findings are reported, as well as the complementary aspects of sonography. Differential diagnosis from tumors of the lesser omentum is also presented.

The vertical distribution of meiofauna in the sediments of Avicennia marina, Bruguiera gymnorrhiza, Ceriops tagal, Rhizophora mucronata and Sonneratia alba at Gazi Bay (Kenya), is described. Seventeen taxa were observed, with highest densities in the sediments of Bruguiera (6707 ind. 10 cm−2), followed by Rhizophora (3998 ind. 10 cm −2), Avicennia (3442 ind. 10 cm −2), Sonneratia (2889 ind. 10 cm−2) and Ceriops (1976 ind. 10 cm−2). Nematodes accounted for up to 95%, of total densities; other common taxa were copepods, turbellarians, oligochaetes, polychaetes, ostracods and rotifers. High densities occurred to about 20 cm depth in the sediment. Especially Ceriops sediments show still high densities of nematodes (342 ind. 10 cm−2) and copepods (11 ind. 10 cm−2) in the deepest layer (15–22 cm). Particle size and oxygen conditions were major factors influencing meiobenthic distribution; Uca burrows had a major impact on distribution and abundance of meiofauna.

This study characterises morphonuclear parameters from normal, cirrhotic, tumoral benign and malignant liver specimens obtained by computerized morphonuclear images analyses. The material is obtained by cytological aspirations or by imprint smears from liver biopsy. The monoparametric analysis differentiates a benign and a malignant cellular populations. In the malignant populations, two types are individualised: the well differentiated and the pleiomorphic hepatocarcinoma. The treatment of the data by canonical projections onto the factorial plan and by discriminant analysis allowed the selection of homogeneous cell populations belonging to each of the pathological groups described above.

We used a high-resolution ultrasound to make electrical recordings from the transversus abdominis muscle in humans. The behavior of this muscle was then compared with that of the external oblique and rectus abdominis in six normal subjects in the seated posture. During voluntary efforts such as expiration from functional residual capacity, speaking, expulsive maneuvers, and isovolume “belly-in” maneuvers, the transversus in general contracted together with the external oblique and the rectus abdominis. In contrast, during hyperoxic hypercapnia, all subjects had phasic expiratory activity in the transversus at ventilations between 10 and 18 l/min, well before activity could be recorded from either the external oblique or the rectus abdominis. Similarly, inspiratory elastic loading evoked transversus expiratory activity in all subjects but external oblique activity in only one subject and rectus abdominis activity in only two subjects. We thus conclude that in humans 1) the transversus abdominis is recruited preferentially to the superficial muscle layer of the abdominal wall during breathing and 2) the threshold for abdominal muscle recruitment during expiration is substantially lower than conventionally thought.

Pancreatic metastasis from renal cell carcinoma is exceptional, but may appear many years after initial diagnosis and radical nephrectomy of an apparently limited tumour. We report one case of an asymptomatic isolated pancreatic metastasis discovered fortuitously, 21 years after right radical nephrectomy for a low-grade renal cancer. In 1969, a 47-year-old man underwent right nephrectomy for renal cell carcinoma of “low-grade malignancy”. At this time, no metastases were evident and he remained well on follow-up.

Suspended matter and sediments from the North Sea were analysed for Al, Fe and Mn. A seasonal variation of Mn and Fe over Al ratios is observed. For most of the year suspended matter is enriched in Mn and Fe relative to average soil composition. No enrichment, and even depletion, occurs during a short period of the year (April-May) coinciding with the occurrence of the spring phytoplankton bloom. Surface sediments from the Southern Bight show the inverse image, with Mn and Fe enrichment occurring only in April-May and no enrichment during the rest of the year. These observations suggest a tight coupling between: (1) the change of redox potential in surface sediments, as triggered by the advection of organic matter from the spring bloom; (2) the outflow of reduced iron and manganese from sediments to the watercolumn; and (3) the enrichment of suspended matter in iron and manganese due to the oxidation-precipitation of reduced iron and manganese. The role of the coastal sediments investigated here as an important site of organic matter mineralization is stressed by the dissolved oxygen profiles indicating a transition from 100

ATP-content and adenylate energy charge (AEC) ratios were determined in two polychaete species (Nereis diversicolor and Nephtys sp.), sampled in ten stations along the heavily polluted Western Scheldt estuary (N. Belgium, S. Holland). The samples were taken between 27 December 1982 and 6 January 1983. Nereis diversicolor was also sampled in an unpolluted brackish water pond, and subjected to artificial stress by drying the organisms on filter paper. Adenine nucleotide levels were determined using the firefly bioluminescence reaction. The light emission was measured with the integration mode. As the "Constant Light Signal" reagent used contained APM and probably ADP itself, both myokinase and pyruvatekinase had to be inactivated before the assay. The use of pepsin in acidic conditions to denaturate these enzymes is discussed. For both N. diversicolor and Nephtys sp., a significant relation between ATP-content and fresh weight is found in most samples. Within each species, ATP-content per g fresh weight is dependent on the sampling method, but is not significantly different between stations. It is higher in Nephtys sp. from the W. Scheldt (130.8 10-5 g ATP/g fresh weight) than in N. diversicolor from the Dievengat (83.9 10-5g ATP/g fresh weight). This value in turn is significantly higher than that for N. diversicolor in the W. Scheldt (64.0 10-5 g ATP/g fresh weight). In the drying experiment, AEC gradually decreases with increasing drying time. In the field, AEC is generally high and not significantly different between the three populations. AEC ratios also do not differ between stations within each population. It is argued that field monitoring of AEC in invertebrates is not valuable as a pollution assessment tool for two reasons. In polluted stations, only pollutant-resistant species will be found, and there is evidence that the maintenance of a stable population is impossible when the individuals constantly have low AECs.

Lithiasis is usually a late complication of renal transplantation reported in approximately 1% of all renal allografts. Underlying predisposing conditions for the formation of calculi are present in almost all cases. Preexisting stones in the donor kidney have been reported once previously. The authors have observed 2 such cases, detected by routine sonography. In 1 case, stone migration into the ureter led to acute postoperative transplant failure; this complication has been reported previously.

The authors report a new ultrasonic sign of urinary tract infection in children: thickening of the renal pelvis and/or ureteral wall. This thickening as encountered in 10 children, (10 months to 12 years) all with urinary tract infection, appears to result from inflammatory changes and to correspond to a sonographic sign of pyelitis and ureteritis. These alterations of the walls are similar to striations and folds described in this pathology on intravenous pyelograms. The thickening was the only sign of abnormality of the urinary tract in two cases; it was observed without reflux in four cases. The demonstration of this pattern should lead to further uroradiological investigations and to appropriate treatment.