Ultrasound of pancreatic transplant complications: a primer for radiologists.

Pancreatic transplantation is an established treatment for patients with type 1 diabetes patients and select type 2 diabetes patients, with excellent survival rates as graft health is evaluated through regular imaging and early detection of complications. Amongst the various imaging methods that may aid in diagnosis of pancreatic transplant complications, ultrasound is a widely available, quick, portable, and cost-effective technique, often used as the sole method to assess for pancreatic transplant complications. When assessing a patient with a pancreatic transplant, the radiologist should be methodical in assessing the vasculature, the pancreatic parenchyma, and the peripancreatic regions. Complications can be categorised based on time from transplant and type of complications, and include vascular, parenchymal, and enteric/anastomotic complications. Doppler has a major role in the diagnosis of vascular complications including arterial and venous thrombosis, arterial stenosis, pseudoaneurysms, and haematomas. Pancreatic complications include rejections and pancreatitis, and are often diagnosed through a combination of clinical, laboratory, and imaging findings, such as pancreatic heterogeneity or the presence of pancreatic pseudocysts. Enteric/anastomotic complications include leaks and bowel obstructions, and may require cross-sectional imaging in addition to ultrasound. This review covers the most common and high-impact vascular, parenchymal, and enteric/anastomotic complications that should be considered in every radiologist's search pattern when assessing a pancreatic graft, as well as their respective postoperative timeframes.

Mitigating seafloor disturbance of bottom trawl fisheries for North Sea sole Solea solea by replacing mechanical with electrical stimulation.

Ecosystem effects of bottom trawl fisheries are of major concern. Although it is prohibited to catch fish using electricity in European Union waters, a number of beam trawlers obtained a derogation and switched to pulse trawling to explore the potential to reduce impacts. Here we analyse whether using electrical rather than mechanical stimulation results in an overall reduction in physical disturbance of the seafloor in the beam-trawl fishery for sole Solea solea. We extend and apply a recently developed assessment framework to the Dutch beam-trawl fleet and show that the switch to pulse trawling substantially reduced benthic impacts when exploiting the total allowable catch of sole in the North Sea. Using Vessel Monitoring by Satellite and logbook data from 2009 to 2017, we estimate that the trawling footprint decreased by 23%, the precautionary impact indicator of the benthic community decreased by 39%, the impact on median longevity of the benthic community decreased by 20%, the impact on benthic biomass decreased by 61%, and the amount of sediment mobilised decreased by 39%. The decrease in impact is due to the replacement of tickler chains by electrode arrays, a lower towing speed and higher catch efficiency for sole. The effort and benthic physical disturbance of the beam-trawl fishery targeting plaice Pleuronectes platessa in the central North Sea increased with the recovery of the plaice stock. Our study illustrates the utility of a standardized methodological framework to assess the differences in time trends and physical disturbance between gears.

Resolving the taxonomic status of biocontrol agents belonging to the Aphidius eadyi species group (Hymenoptera: Braconidae: Aphidiinae): an integrative approach.

Species that belong to the Aphidius eadyi group have been used as biocontrol agents against Acyrthosiphon pisum worldwide. However, despite their extensive use, there are still gaps in our knowledge about their taxonomy and distribution. In this study, we employed an integrative taxonomic approach by combining genetic analyses (mtDNA COI barcoding) with standard morphological analyses and geometric morphometrics of forewing shape. We identified three species within the A. eadyi species group, viz., A. smithi, A. eadyi and A. banksae. Genetic separation of all three species was confirmed, with mean genetic distances between species ranging from 5 to 7.4%. The following morphological characters were determined as the most important for separating species of the A. eadyi group: number and shape of costulae on the anterolateral part of the petiole, shape of the central areola on the propodeum, and shape and venation of the forewings. The differences in wing shape of all three species were statistically significant, but with some overlapping. We identified A. banksae as a widely distributed pea aphid parasitoid, whose known range covers most of the western Palaearctic (from the UK to Israel). Aphidius banksae is diagnosed and redescribed.

Molecular and morphological variability within the Aphidius colemani group with redescription of Aphidius platensis Brethes (Hymenoptera: Braconidae: Aphidiinae).

We have identified the following three taxa related to the Aphidius colemani species group, which are important biological control agents: Aphidius colemani, Aphidius transcaspicus and Aphidius platensis. Using partial sequences of the mitochondrial cytochrome oxidase subunit I (mtCOI) gene and geometric morphometric analysis of the forewing shape, we have explored the genetic structure and morphological variability of the A. colemani group from different aphid host/plant associations covering a wide distribution area. The topology of the maximum parsimony and maximum likelihood trees were identical with 98-100% bootstrap support, clustering A. colemani, A. platensis and A. transcaspicus into separate species. The distances among the taxa ranged from 2.2 to 4.7%, which is a common rate for the between-species divergence within the subfamily Aphidiinae. Differences in the shape of the forewing investigated within the biotypes of A. colemani group are congruent with their genetic diversification. Both A. platensis and A. colemani share a common host range pattern, and it would be interesting to estimate and compare the role of these two species in future biological control strategies against aphids of economic importance. Our results indicate that 'genetic screening' is a reliable approach for identification within the A. colemani group. The high variation in the wing shape among species, including a significant divergence in the wing shape among specimens that emerged from different hosts, makes the forewing shape and wing venation less reliable for species determination. Aphidius platensis is diagnostified and redescribed, and the key for the A. colemani group is presented.

Effect of pulverized natural bone mineral on regeneration of three-wall intrabony defects. A preclinical study.

AIMS: The objective of this study is to evaluate the effects of a paste-like bone substitute material with easy handling properties and improved mechanical stability on periodontal regeneration of intrabony defects in dogs. MATERIALS AND METHODS: Mandibular and maxillary first and third premolars were extracted, and three-wall intrabony defects were created on second and fourth premolars. After a healing period of 3 months, acute type defects were filled with a paste-like formulation of deproteinized bovine bone mineral (DBBM) (particle size, 0.125-0.25 mm) in a collagenous carrier matrix (T1), pulverized DBBM (particle size, 0.125-0.25 mm) without the carrier (T2), or Bio-Oss® granules (particle size, 0.25-1.00 mm) as control (C). All defects were covered with a Bio-Gide® membrane. The dogs were sacrificed after 12 weeks, and the specimens were analyzed histologically and histometrically. RESULTS: Postoperative healing of all defects was uneventful, and no histological signs of inflammation were observed in the augmented and gingival regions. New cementum, new periodontal ligament, and new bone were observed in all three groups. The mean vertical bone gain was 3.26 mm (T1), 3.60 mm (T2), and 3.81 mm (C). That of new cementum was 2.25 mm (T1), 3.88 mm (T2), and 3.53 mm (C). The differences did not reach statistical significance. The DBBM particles were both incorporated in new bone and embedded in immature bone marrow. CONCLUSIONS: The results of this preclinical study showed that the 0.125-0.25-mm DBBM particles in a powder or paste formulation resulted in periodontal regeneration comparable to the commercially available DBBM. Osteoconductivity, in particular, was not affected by DBBM size or paste formulation. CLINICAL RELEVANCE: The improved handling properties of the paste-like bone substitute consisting of small DBBM particles embedded in a collagen-based carrier hold promise for clinical applications.

Comparison between the deconvolution and maximum slope 64-MDCT perfusion analysis of the esophageal cancer: is conversion possible?

PURPOSE: To estimate if CT perfusion parameter values of the esophageal cancer, which were obtained with the deconvolution-based software and maximum slope algorithm are in agreement, or at least interchangeable. METHODS: 278 esophageal tumor ROIs, derived from 35 CT perfusion studies that were performed with a 64-MDCT, were analyzed. "Slice-by-slice" and average "whole-covered-tumor-volume" analysis was performed. Tumor blood flow and blood volume were manually calculated from the arterial tumor-time-density graphs, according to the maximum slope methodology (BF(ms) and BV(ms)), and compared with the corresponding perfusion values, which were automatically computed by commercial deconvolution-based software (BF(deconvolution) and BV(deconvolution)), for the same tumor ROIs. Statistical analysis was performed using Wilcoxon matched-pairs test, paired-samples t-test, Spearman and Pearson correlation coefficients, and Bland-Altman agreement plots. RESULTS: BF(deconvolution) (median: 74.75 ml/min/100g, range, 18.00-230.5) significantly exceeded the BF(ms) (25.39 ml/min/100g, range, 7.13-96.41) (Z=-14.390, p<0.001), while BV(deconvolution) (median: 5.70 ml/100g, range: 2.10-15.90) descended the BV(ms) (9.37 ml/100g, range: 3.44-19.40) (Z=-13.868, p<0.001). Both pairs of perfusion measurements significantly correlated with each other: BF(deconvolution), versus BF(ms) (rS=0.585, p<0.001), and BV(deconvolution), versus BV(ms) (rS=0.602, p<0.001). Geometric mean BF(deconvolution)/BF(ms) ratio was 2.8 (range, 1.1-6.8), while geometric mean BV(deconvolution)/BV(ms) ratio was 0.6 (range, 0.3-1.1), within 95% limits of agreement. CONCLUSIONS: Significantly different CT perfusion values of the esophageal cancer blood flow and blood volume were obtained by deconvolution-based and maximum slope-based algorithms, although they correlated significantly with each other. Two perfusion-measuring algorithms are not interchangeable because too wide ranges of the conversion factors were found.

Patterns of cranial ontogeny in lacertid lizards: morphological and allometric disparity.

We explored the ontogenetic dynamics of the morphological and allometric disparity in the cranium shapes of twelve lacertid lizard species. The analysed species (Darevskia praticola, Dinarolacerta mosorensis, Iberolacerta horvathi, Lacerta agilis, L. trilineata, L. viridis, Podarcis erhardii, P. melisellensis, P. muralis, P. sicula, P. taurica and Zootoca vivipara) can be classified into different ecomorphs: terrestrial lizards that inhabit vegetated habitats (habitats with lush or sparse vegetation), saxicolous and shrub-climbing lizards. We observed that there was an overall increase in the morphological disparity (MD) during the ontogeny of the lacertid lizards. The ventral cranium, which is involved in the mechanics of jaw movement and feeding, showed higher levels of MD, an ontogenetic shift in the morphospace planes and more variable allometric patterns than more conserved dorsal crania. With respect to ecology, the allometric trajectories of the shrub-climbing species tended to cluster together, whereas the allometric trajectories of the saxicolous species were highly dispersed. Our results indicate that the ontogenetic patterns of morphological and allometric disparity in the lacertid lizards are modified by ecology and functional constraints and that the identical mechanisms that lead to intraspecific morphological variation also produce morphological divergence at higher taxonomic levels.

Evaluation of a web-based application versus conventional instruction in the undergraduate curriculum of fixed prosthodontics.

AIMS: The present study aims to investigate the implications of web-based delivery of identical learning content for time efficiency and students' performance, as compared to conventional textbook resources. MATERIALS AND METHODS: Two cohorts of third year undergraduate dental students in 2003 (n = 35) and 2006 (n = 32) completed the study. Following a baseline pre-test, the students were divided into two groups and given 3 weeks for studying identical content using a web-based application (group A) or a conventional paper manuscript (group B). Post-test, end of semester examination and a final retention test were taken. Test scores and studying time was registered for both cohorts in 2003 and 2006. RESULTS: Group A and B knowledge gain was highly significant between the average per cent scores from pre-test, post-test and end of semester examination in both cohorts in 2003 and 2006 (P < 0.005). Group A spent 1.6× (2003) to 2.6× (2006) less time studying than group B. The average total studying time recorded for group B was 5.1 h using 6.2 learning sessions in 2003 and 3.5 h using 4.4 sessions in 2006. With group A, significantly less time was measured for studying through web-based content using an average of 2.5 h over 4.4 learning sessions in 2003 and 1.5 h added over three sessions in 2006. CONCLUSIONS: Web-based delivery of identical content results in less overall studying time as compared to textbook delivery. These results appear independent of the students' own preference of the learning medium.

Cytoreductive surgery and modified heated intraoperative intraperitoneal chemotherapy (HIPEC) for advanced and recurrent ovarian cancer -- 12-year single center experience.

BACKGROUND: The present study reviews our 12-year results with cytoreductive surgery and HIPEC in patients with advanced primary and recurrent ovarian cancer. METHODS: During the period from January 1995 to December 2007, 56 patients (31 with primary and 25 with recurrent epithelial ovarian cancer) underwent cytoreductive surgery and HIPEC (Doxorubicin intra-operatively, and cisplatin next 1-5 postoperative days) at our department. RESULTS: 52 (92.8%) patients had no gross residual disease after the complete surgical procedure (Sugarbaker completeness of cytoreduction CC, score 0-1), and 4 patients had macroscopic residual disease (CC-2 or CC-3) Average PCI (peritoneal cancer index) was 13.4 (4-28). Mean follow-up was 56 months (range, 1-135). The median operation time was 279min (range 190 + or - 500min). Median total blood loss was 850mL (range 250 + or - 1550mL). The median survival time was 34.1 months for primary, 40.1 for recurrent ovarian cancer without statistically significance difference (p>0.05) and median disease-free survival was 26.2 months. The PCI was equal or less than 12 in 31 patients and their median survival time was statistically significant longer than median survival time of months for the 25 patients with PCI greater then 12 (p<0.01). Morbidity and mortality rate were 17.8% (10/56) and 1.8% (1/56). CONCLUSION: This series indicates that in the majority of patients with primary and recurrent advanced ovarian cancer, cytoreductive surgery combined with HIPEC can lead to a substantial increase in subsequent rates of disease-free and overall survival.

[Delayed MDCT in preoperative analysis of the hypopharyngeal postcricoid carcinomas].

INTRODUCTION: Determination of borders of the postcricoid tumors is of great significance during preoperative analysis, because it can be of considerable influence on operative treatment and its planning. Therefore, exact demarcation, delineation and opacification of tumor zone on CT analysis is crucial. MATERIAL AND METHOD: Late CT scan delay of 150 sec and slow vein flow of contrast agents of 1 ml/sec is radiological method of choice in preoperative evaluation of carcinoma of the post-cricoid region. For our purposes we used modern MSCT Light Speed GE 64, with slice thick of 2.5 mm (retro recon of 0.625) with software postprocesing. RESULTS AND DISCUSSION: In our study, we have detaily analized 25 patients with clinically proved carcinoma of hypopharynx, of which 8 had the hardest form of tumor. Control group were patients to whom CT scan was done by standard protocol and CT time scan of 50 sec. With all 8 of them, scanned by protocol of delay time of 150 sec, was proved a statistically important validity of interpretation and demarcation of tumors. CONCLUSION: Delay time on CT scanning is proved to be efficient protocol for visualization of neck soft tissues which includes the walls of hypopharynx.

[Solving of complications arising during and after application self-expandible metallic stents in palliation of malignant dysphagia].

INTRODUCTION: During palliative treatment of malignant disphagia in inoperabile patients various and serious complications may occur and compromite the method of treatment if there were not solved. AIM: Goal is to present the most frequent complications due to esophageal stenting and the way of their solving. MATERIALS AND METHOD: From 1996. to 2009. in 237 patients (164 esophageal carcinoma, 33 carcinoma of the esophagogastric junction, 14 bronchial carcinoma, 7 esophagojejunal anastomosis, 9 esophageal fistulas) 245 stents have been placed (54 uncovered and 191 covered). Mean survival period was 14.7 months (ranged from 1 do 33 months). Esophageal perforation (1), stent migration (9), malignant tissue ingrowth (31) and overgrowth (24) have been revealed by barium contrast study during follow up. Perforation was solved by placing covered stent, migration by removing migrated stent endoscopically or surgically, ingrowth and overgrowth by balon dilating or restenting under the fluoroscopically guidance and control. CONCLUSION: One can expect and recognize complications regarding esophageal stenting because it is the only way for their sucsessfull treatment.

[Computerized tomography in postoperative monitoring of patients with the Whipple operation--characteristics of CT findings].

We presented the postoperative CT findings of patients after the Whipple's operation (cephalic pancreaticoduodenectomy), performed for the pancreatic head cancer, or ampullary carcinoma. Technique of the Whipple's operation is described, and normal and pathological postoperative CT findings, which are characteristic for the immediate (early) and delayed (late) follow-up period, are presented. In addition, difficulties in differentiation of afferent jejunal loop from the recurrent tumor by CT are discussed, and references from the literature about the possibilities of successful visualization of the afferent jejunal loop are cited. Possible locations and CT appearances of the tumor recurrences are presented. An overview of the literature is provided.

The chaotic sequences in the Bray-Liebhafsky reaction in an open reactor.

Attractor reconstruction is done from the time series obtained by experimental investigation and by deterministic and stochastic simulation of the Bray-Liebhafsky oscillatory reaction. The appearance of deterministic chaos is confirmed and proven by both simulation and experiment, determining Lyapunov exponents for the sequences of flow rate values, as the control parameter. Moreover, unusual chaotic series were additionally recorded in the experiments, which cannot be found in deterministic numerical simulations. Therefore, an explanation of the difference between the dynamic behavior in the experiment and the deterministic simulation was sought and stochastic simulations based on the same reaction model were particularly useful. The fine structure of the chaotic windows, derived from the analysis of deterministic simulations in the range of flow rate values, made the system highly susceptible to noise induced effects, in general.

The accuracy of ultrasonography in classification of groin hernias according to the criteria of the unified classification system.

BACKGROUND: The modern concept of type-related individualized groin hernia surgery imposes a demand for precise and accurate preoperative determination of the type of groin hernia. The aim of this prospective study was to evaluate the accuracy of ultrasonography in classification of groin hernias, according to the criteria of the unified classification system. Unified classification divides groin hernias into nine types (grades): type I (indirect, small), II (indirect, medium), III (indirect, large), IV (direct, small), V (direct, medium), VI (direct, large), VII (combined-pantaloon), VIII (femoral), and O (other). PATIENTS AND METHODS: One hundred and twenty-five adult patients with clinically diagnosed or suspected groin hernias were examined. Ultrasonography of both groins was performed with a 5 to 10-MHz linear-array transducer. Preoperative ultrasonographic findings of type of groin hernia were compared with the intraoperative findings, which were considered the gold standard. RESULTS: Total accuracy of ultrasonography in determination of type of groin hernia was 96% (119 of 124 correct predictions of type of groin hernia compared with surgical explorations). All hernias of types I, IV, V, VII, and VIII were correctly identified with ultrasonography (sensitivity and specificity 100%). In the remaining five cases of the 124 (4%), hernia was incorrectly classified with ultrasonography: type VI (direct, large) was misdiagnosed as type III (indirect, large) in three cases, type III as type VI in one case, and type III as type II (indirect, medium) in one case. The sensitivity and the specificity of ultrasonography in classifying type II were 100 and 99%, respectively, for type III, 85 and 97%, and for type VI, 90 and 99%. CONCLUSION: Ultrasonography of the groin regions could be used with great accuracy for precise classification of groin hernias in adults. Each type of groin hernia, according to the unified classification system that we used for classification, has a characteristic ultrasonographic presentation, which is demonstrated in this study.

[CT endoscopy in urinary bladder lesions detection].

AIM: To evaluate applicability and efficacy CT virtual cystoscopy in detection of urinary bladder tumors. MATERIAL AND METHODS: During the period of 14 months, 17 patients with suspicion or present of some urinary bladder lesions has undergone CT virtual and conventional cystoscopy. After examination, all data were moved to the workstation for interactive endoluminal navigation. After that, radiologist analyzed transversal and virtual images without results of conventional cystoscopy and made conclusion. RESULTS: Results were divided according to their basic clinical application. By using this method, all lesions over 5 mm in size were revealed. In the group of patients that were followed up for urinary bladder tumors, three patients with carcinomatous lesion were revealed. Two tumors of bladder vault that were missed on transversal scan were visualized by virtual cystoscopy. Useful additional information about tumor spread was given in two patient. One tumor inside the bladder diverticulum was detected, that was not seen by conventional cystoscopy. In two patients, endoluminal origin of mass that could not be confirmed by conventional radiologic methods, was determined. CONCLUSION: CT virtual cystoscopy is useful method and technics that promise a lot, especially in following situations: a) follow up of bladder tumors; b) supplemental estimation of endoscopically hardly accessible regions; c) differential diagnosis between intravesical and exravesical lesions. Optimal estimation offers adequate bladder distension with patient positioned on the back and on the belly and interpretation as well as on transversal and virtual images.

Endoanal ultrasonography in establishing the diagnosis of fecal incontinence.

Visualisation of the rectum, rectoanal junction and adjacent structures is very demanding and challenging both with technical and medical side. Local staging of rectal and anal tumor and perianal neoplasm by conventional and sibgle slice CT or by barium enema study is not so valuable. These methods can not visualise fistulous communication in inflamatory bowel diseases and have not any role in evaluation of fecal incontinence. During last decade, endoscopic ultrasound and magnetic resonance imaging have been recognised as methods of choice in establishing diagnosis of rectal, perirectal, anal and perianal diseases. The aim of this article is to review the possibilities of endoanal ultrasound in evaluation of fecal incontinence.

Fluoroscopically guided insertion of self-expandable metal esophageal stents for palliative treatment of patients with malignant stenosis of esophagus and cardia: comparison of uncovered and covered stent types.

The aim of this retrospective study was to present and compare the results of using two different types of esophageal self-expanding stents (uncovered and covered) for palliative treatment of patients with inoperable malignant stenosis of the esophagus and cardia. Over a period of 8 years, 152 patients underwent fluoroscopically guided insertion of metal esophageal stents. We inserted uncovered esophageal nitinol Strecker stents in 54 patients (group I) and covered esophageal Ultraflex stents in the remaining 98 patients (group II). The stent insertion procedure was successively performed in all patients. Closure of esophageal fistula by covered stents was achieved in 8/8 patients. Mean dysphagia score was significantly decreased in both patient groups at 4 weeks follow-up: from 2.73 before stent insertion to 0.15 in group I, and from 2.67 to 0.05 in group II (on 0-4 scale). Eighty-eight per cent of patients with covered stents and 54% with uncovered type were free of symptoms during follow-up. Complications occurring during follow-up and their comparative frequency in the two groups of patients were as follows (group I: group II%): stent migration (0:10%); tumor or granulation tissue ingrowth (100:53%); overgrowth at the ends of stents (17:30%); restenosis causing recurrent dysphagia (37:8%); and appearance of esophageal fistulas (8:6%). In conclusion, fluoroscopically guided insertion of self-expandable esophageal stents is a safe and comfortable method of palliation for patients suffering with malignant dysphagia. In selection of a stent, covered types should be given priority for prevention of restenosis.