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The effectiveness and impact of internal audit procedures implemented within an Operator’'s Well Engineering organization is described and how it ensures quality and integrity of the performance in the company’'s operating units. The work is based on four years of internal operations audit data where the results of operations audits have been analysed to identify trends in the levels of compliance and the quality of the technical work carried out in the different operations group. It is explained how compliance with policies, procedures and standards is set and monitored within the Company and also show the effect of internal audit activities on performance. One of the outcomes of the audit process is the continuous refinement of the audit tools themselves. The audit results also highlight the need to review and refine the well delivery process itself and show correlation between audit results and operational performance. The results provide useful metrics and give an indication of the state of the health of the well engineering organisation.

Zielsetzung Analyse weichgeweblicher magnetresonanztomographischer (MRT-)Befundmuster fruher Stadien rheumatischer Erkrankungen durch retrospektive Auswertung von MRT-Untersuchungen der Hand.

PURPOSE We sought to evaluate the low-contrast performance of a newly developed needle image plate/line scanner (NIP) computed radiography system in comparison with a standard powder image plate/flying-spot scanner (PIP) system. MATERIALS AND METHODS A total of 36 images of a CDRAD phantom, simulating low-contrast structures with different drill holes of different diameters, were obtained with both imaging systems using 9 different exposure variables. All images had window and level set to generate consistent density and contrast. In addition, multiscale contrast-dependent contrast amplification was applied to some of the images. All images obtained were printed and presented to a total of 10 observers (5 radiologists, 5 engineers/physicists), who were blinded to both the image plate and parameter setting used. The smallest detectable drill hole depth (= contrast) correctly identified was recorded for each diameter. The median values observed were calculated and tested for statistical differences between PIP and NIP using Student t test for matched pairs (level of significance P < or = 0.05). RESULTS At all but 2 settings of the variables, NIP images depicted significantly lower contrast levels (= lower depth of drill holes) compared with PIP images. The 2 settings also showed a trend towards better low contrast depiction with NIP. In no case was low contrast performance better using PIP images. CONCLUSION Images obtained with needle image plate/line scanner provide superior low contrast performance compared with the images obtained with powder image plate/flying-spot scanner.

Purpose Assessment of low-contrast details in digital radiographs on different review displays (RD). Materials and methods 20" flat screen panels (RD1: standard color LCD-TFT, RD2: monochrome LCD-TFT for radiological reading, RD1*: RD1 with optional image inversion; 205 cd/m (2) luminance, respectively) were evaluated. At 30 lx ambient lighting, 10 radiologists gradually increased the contrast (constant steps) for both a homogeneous picture and a cutout of a thorax radiography of n = 480 simulated nodules until they became recognizable. Results In the case of bright nodules on an anthropomorphic background, the use of image inversion produced significantly better results. No other significant differences were detected. Conclusion Provided that the working environment is not bright, the results suggest that low-cost RD can be used for the recognition of low-contrast details in radiographies of the chest. Further studies including more display models are necessary. Among different ambient lighting and luminance settings, these studies should include a closer analysis of the special features of digital systems such as brightness/contrast adaptation, picture enlargement (zoom shot), and image inversion.

The purpose of this study was to analyze different patient positioning strategies for minimizing artifacts of the shoulder girdle in head and neck CT. Standardized CT examinations of three positioning groups were compared (P: patients pushed their shoulders downwards; D: similar optimization by a pulling device; N: no particular positioning optimization). Parameters analyzed were the length of the cervical spine not being superimposed by the shoulder girdle as well as noise in the supraclavicular space. In groups P and D, the portion of the cervical spine not superimposed was significantly larger than in group N (P: 10.4 cm; D: 10.6 cm; N: 8.5 cm). At the supraclavicular space, noise decreased significantly (P: 12.5 HU; D: 12.1 HU; N: 17.7 HU). No significant differences between the two position-optimized groups (P and D) were detected. Optimized shoulder positioning by the patient increases image quality in CT head and neck imaging. The use of a pulling device offers no additional advantages.

[reaction: see text] Organocopper compounds prepared by the transmetalation of functionalized arylmagnesium halides with CuCN.2LiCl undergo smooth cross-coupling reactions with aryl fluorides and tosylates bearing a carbonyl function in the ortho position in the presence of Co(acac)(2) (7.5 mol %), Bu(4)NI (1 equiv), and 4-fluorostyrene (20 mol %) as promoters in DME/THF/DMPU leading to polyfunctional aromatics or heterocycles.

Purpose We aimed to evaluate the accuracy of multidetector computed tomography (MDCT) venous mapping for the localization of the right adrenal veins (RAV) in patients suffering from primary aldosteronism. Methods MDCT scans of 75 patients with primary aldosteronism between March 2008 and November 2011 were evaluated by two readers (a junior [R1] and a senior [R2] radiologist) according to the following criteria: quality of RAV depiction (scale, 1-5), localization of the RAV confluence with regard to the inferior vena cava, and depiction of anatomical variants. Results were compared with RAV venograms obtained during adrenal vein sampling and corroborated by laboratory testing of cortisol in selective RAV blood samples. Kappa statistics were calculated for interobserver agreement and for concordance of MDCT mapping with the gold standard. Results Successful RAV sampling was achieved in 69 of 75 patients (92%). Using MDCT mapping, adrenal veins could be visualized in 78% (R1, 54/69) and 77% (R2, 53/69) of patients. MDCT mapping led to correct identification of RAV in 70% (R1, 48/69) and 88% (R2, 61/69) of patients. Venograms revealed five cases of anatomical variants, which were correctly identified in 60% (R1, R2). MDCT-based localizations were false or misleading in 16% (R1, 11/69) and 7% (R2, 5/69) of cases. Conclusion Preinterventional MDCT mapping may facilitate successful catheterization in adrenal vein sampling.

The halogeno complexes (CO)5ReX (1a–c) (X = Cl, Br, I) react with 1-nitroso-2-naphthol C10H6N(O)OH (2) in refluxing CH2Cl2 to give the substitution product cis-(CO)4Re{C10H6ON(O)} (3) via HX and CO elimination in good yield. Compound 3 is coordinated to the Re centre by the bidentate chelate ligand via the N-atom of the nitroso and O-atom of the naphtholato groups. The same reaction in refluxing toluene, however, gave no HX elimination but instead, the fac-(CO)3XRe{C10H6ON(H)} (4–6) complexes are formed, which contain the rare, N,O-chelating ligand 1,2-naphthaquinone-2-imine. The nitroso function of 2 has been reduced to the imine function by an intermolecular redox process, which was confirmed by the detection of CO2 generated during the reaction. The new compounds 3–6 have been characterised by their IR, 1H and 13C NMR, UV/Vis and mass spectra, as well as by X-ray structure analyses. The ReI centres show a distorted octahedral coordination of the CO and X (in 4–6) ligands and the almost planar aromatic (3) or quinoid (4–6) N,O chelating ligands. (© Wiley-VCH Verlag GmbH & Co. KgaA, 69451 Weinheim, Germany, 2005)

Ein filmbasiertes radiologisches Lehrarchiv erfordert einen hohen personellen, logistischen und finanziellen Aufwand. Die Verbindung von Computer- und Netzwerktechnologie erlaubt mittlerweile die sog. „Workflowintegration“ der Verbreitung radiologischer Lehrfalle innerhalb einer Institution (Intranet) oder im World Wide Web (Internet).

Hintergrund Sowohl bei Neuanschaffungen als auch fur technische Aktualisierungen von PAC-Systemen ist ein effizientes Handling von Bildarchivierung und -abruf besonders zu beachten.

Technological progress and the rising cost pressure on the healthcare system have led to a drastic change in the work environment of radiologists today. The pervasive demand for workflow optimization and increased efficiency of its activities raises the question of whether by employment of electronic systems, such as RIS and PACS, the potentials of digital technology are sufficiently used to fulfil this demand. This report describes the tasks and structures in radiology departments, which so far are only insufficiently supported by commercially available electronic systems but are nevertheless substantial. We developed and employed a web-based, integrated workplace system, which simplifies many daily tasks of departmental organization and administration apart from well-established tasks of documentation. Furthermore, we analyzed the effects exerted on departmental workflow by employment of this system for 3 years.

Die bisherige Erstattung stationarer Krankenhausleistungen auf Basis tagesgleicher Pflegesatze, Fallpauschalen und Sonderentgelte ist durch das Diagnosis-related-groups- (DRG-)System abgelost worden. Operationen- und Prozeduren- (OPS-)Schlussel 301 konnten in der Radiologie bis 2004 mit entsprechender Anpassung des „Radiologie-Informations-System“ (RIS) vollautomatisiert erfasst werden. Durch die immer feinere Differenzierung der OPS-Codes in der Version 2005 ist eine eindeutige Ermittlung der OPS-Codes jedoch nicht mehr vollautomatisch moglich. Ziel ist es, diese zusatzlichen Aufgaben mit so wenig Mehraufwand wie moglich zu erbringen.

Characters of copulation posture and copulation structures were projected on a phylogenetic tree, which was reconstructed with different morphological characters. The way males were attached to females during copulation was observed. The basic copulation position was transformed several times into more complex attachments. The stem species of two monophyletic taxa (“Pitcher-plant group and related species” and Histiostoma feroniarum group) developed conspicuously enlarged setae on legs I and II. They were used during copulation to anchor into the female's cuticula to support the male's attachment. The female copulation structure divided into two parts (ending of the bursa copulatrix and a cuticular fold) was identified to be a character which developed early within the Histiostomatidae. Interesting transformations were derived from this structure: e.g., the conspicuously enlarged and rounded copulation structure of Histiostoma maritimum Oudemans, 1914. Male dimorphisms were observed in 3 species:...

Untersucht wurde, ob der 3D-US die Beurteilung von Mammaherdbefunden verbessern kann. 60 Patientinnen wurden mit 2D- und 3D-US (Logiq 9 der Fa. GE, 14 MHz, multiplanare Rekonstruktionen in 3 Ebenen) untersucht. Die Herdlasionen wurden sonographisch nach BIRADS klassifiziert. Als Referenzmethode stand in allen Fallen das Ergebnis der histopathologischen Untersuchung zur Verfugung. Bei den 38 malignen und 22 benignen Lasionen ergab sich mit der 2D-US eine Sensitivitat/Spezifitat von 92/81%, mit der 3D-US von 97/72% und bei der Kombination von 2D- und 3D-US von 97/81%. Bei malignen Tumoren zeigt sich im 3D-US eine sternformige echoarme Formation mit Retraktion des umgebenden Gewebes. Der 3D-US ermoglicht die mehrdimensionale Darstellung von Mammaherdbefunden, in der als Malignitatskriterium die Retraktion des umgebenden Gewebes eindrucksvoll zur Darstellung kommt.

Digital imaging in mammography is becoming more and more accepted using both computed (CR) and direct radiography (DR). These techniques will soon be used in screening programs. Therefore, quality assurance for this technique is indispensable. The relevance of the current regulations, such as EPOC and the German QS-RL was investigated. For the investigation, a breast phantom and appropriate software were developed. Both were tested using digital mammography systems from six manufactures. Quality assurance parameters (such as contrast to noise ratio and contrast resolution) were calculated from these data sets. The results should be considered in future standards for mammography (IEC respectively DIN). In addition, this type of test procedure is time saving and enables a reduction in test devices, i. e. in costs.

Objective Evaluation of systematic epidemiological data regarding clinical characteristics, sex distribution and autoantibody pattern in Caucasian children with autoimmune hepatitis (AIH). Study design Data of 142 children presenting with AIH (97 girls and 45 boys) have been analysed for their clinical, serological, and histological profile. Results Clinical findings were jaundice (58%), unspecific weakness (57%), anorexia (47%), abdominal pain (38%) and paleness (26%). One hundred and three children (73%) (68 girls, 35 boys, 1.9:1) had AIH type 1 and 35 patients (25%) (27 girls, 8 boys, 3.4:1) type 2 due to specific autoantibodies. Four children could not be classified. Histology of 122 children revealed active hepatitis in 64 (52%), cirrhosis in 46 (38%), and mild inflammatory activity in 12 individuals (10%). The most prevalent HLA type was B8. Conclusion In our cohort the prevalence of AIH was half as frequent in boys as in girls. Type 1 was the most frequent diagnosis (73%) and was more prevalent in older children. Type 2 was equally age distributed. The clinical presentation of AIH in children was unspecific and type I and type II could only be differentiated by the determination of the specific autoantibodies. Ninety percent of patients presented with high inflammatory activity or liver cirrhosis.

PURPOSE: Recommendations for archiving digital radiological image data based on the comparison of retrieval times for different PACS archive levels. MATERIALS AND METHODS: For a large PACS installation (Agfa Impax, Release 4.1), image retrieval times for radiological standard examinations (chest radiographs with 2, MRI with 250, CT with 100 and 1000 images; n = 120, each) from hard disk array, magneto-optical disk (MOD), and magnetic tape archives (TAPE) were examined in high and low network traffic load. RESULTS: Even large CT examinations (1000 images) were available from hard disk arrays within 4.0 +/- 0.8 s, smaller studies within 1.8 +/- 0.3 s. Radiographic image retrieval from MOD (30 +/- 4.7 s) was more then 50 % faster than from TAPE. For typical cross-sectional studies, the velocity gain amounted to 19 %. For both technologies, no significant difference was found for large CT examinations (651 +/- 144 s). For high and low network traffic load scenarios, image retrieval times from hard disk, MOD, and TAPE archives increased by 87 %, 7 %, and 22 %, respectively. CONCLUSION: Hard disk arrays are specifically suited as departmental intermediate storage media because they allow fast access to current and previous examinations within a short time. Performance properties enable both MOD and TAPE systems to serve as long-term archives. However, MOD archives are less flexible in the expansion of storage capacity and at present the medium costs per memory unit are about 2 - 3 times higher than for tape archives. The use of existing MOD-archives may be adequate as intermediate archives. For new PACS installations or system expansions, however, it is recommended to combine a sufficiently large local data memory (RAID) with data storage on tape archives outside the radiological unit that can be used by other departments as well. Future development of hard disk prices will show whether archiving for the whole data retention period may be handled by RAID systems. In any case, prefetching problems and waiting periods for demanded pre-studies would not occur any more.

Background: Adverse drug reactions (ADRs) contribute significantly to patient morbidity and mortality, as well as to costs for healthcare systems. Our aim was to evaluate the type and incidence of ADRs in a paediatric hospital population, comparatively ascertained by two different methodological approaches. Methods: Our prospective study enrolled all patients admitted to two of the general children wards (46 beds) and the paediatric intensive care unit (6 beds) at the HELIOS Klinikum Wuppertal teaching hospital in Germany, over the study period of 3 months. We used two methods to detect ADRs. The intensified surveillance system relied on a trained physician conducting ward rounds and assessing patient charts. The computer-assisted screening of pathological laboratory parameters used values slightly below or above the age-specific normal range as a trigger signal for a potential ADR, which was subsequently assessed by trained personnel. Results: By applying both methods simultaneously we observed that 14.1% of children experienced an ADR while they were hospitalised and 2.7% of children were admitted to hospital because of the ADR. Intensified surveillance resulted in the detection of 101 ADRs in 11.9% of patients, predominantly presenting with gastrointestinal symptoms, skin and CNS disorders; computer-assisted screening identified 45 ADRs in 5.7% of patients, mainly with drug-induced blood dyscrasia and liver damage. Furthermore, the ADRs detected by the intensified method were more severe, affected younger children and showed a closer causal attributability to the reaction than the ADRs observed by the computerised method. The spectra of drugs involved were similar, with the anti-infectives being suspected most frequently. The sensitivities of the intensified surveillance system and the computerised surveillance screening came to 67.2% and 44.8%, respectively, with computer-assisted screening having a specificity of 72.8%. The mean positive predictive value of the pathological laboratory values under surveillance by computer-assisted screening was 18.6%. Approximately 25% of ADR-related drugs administered were used for off-label indications. Conclusion: Using the published literature for comparison, we found that ADRs occur as frequently in paediatric patients as in adult patients. Intensified surveillance and computerised surveillance applied in the paediatric setting show substantial differences in their detection specificities. A higher number of and more severe ADRs can be detected by intensified surveillance than by computerised surveillance, but require higher personnel resources.

It is well established that during lamivudine treatment, mutations emerge within the polymerase gene but there is little information about the selection of other mutations in the whole hepatitis B virus (HBV) genome. The aim of this study was to investigate whether mutations outside this region are selected during lamivudine treatment. The complete HBV genomes of six HBsAg positive chronically infected children were isolated from the children's sera before, at the beginning and during lamivudine treatment, amplified and sequenced directly. A change in the mutation rate and type in periods with and without treatment for one and the same patient were examined longitudinally because blood samples were taken long before treatment started. During the testing period before treatment, 12 mutations occurred within 11.7 ± 8.1 months in all genomes, resulting in a mutation rate of 1.1 × 10−3 substitutions per site per year. During treatment with lamivudine, 20 mutations occurred in all patients within an average period of 7.6 ± 1.2 months, giving an average mutation rate of 1.8 × 10−3 substitutions per site per year. The 20 mutations observed during the treatment period occurred in only 4 of the patients and only 3 patients experienced nonsense mutations during lamivudine treatment. The mutations were spread across the entire genome with a non-significant cluster during treatment in the P-ORF (18 mutations vs. 7, P = 0.073) and S-ORF (11 vs. 2, P = 0.063). Mutations causing drug resistance did not emerge. This study describes the changes in the complete HBV genome in the spontaneous course of infection and during lamivudine treatment. An increased mutation rate and the occurrence of specific mutations could not be proven for the early phase of lamivudine treatment. J. Med. Virol. 77:194–202, 2005. © 2005 Wiley-Liss, Inc.

To analyze the benefit of a departmental IT group in comparison to support by hospital IT groups or system manufacturers in a completely digitized radiological department. The departmental IT group comprises a fulltime IT specialist, two student assistants and four clinical employees participating 1 day/week. For 18 months IT problems were quantified and specified according to urgency, responsibility and affected system by use of an intranet-based reporting system. For each IT service provider the performance and duration of problem solution was evaluated. In 18 months 3,234 IT problems emerged. 88.7% were solved by the departmental IT group. In 474 cases (14.7%) a solution within 2 h was required. The departmental IT group solved 35.8% within 30 min, system manufacturers needed 18 h 38 min in mean. The departmental IT group solved 90.2% of the problems within a time limit. System manufacturers met the limit in 60.1% with a mean duration of 7 days 21 h. In 6.7% of the cases, support by system manufacturers was indispensable. A considerable proportion of IT problems in completely digitized radiological departments can be solved by a departmental IT group, providing a fast and cost-efficient first-level IT support with effective prevention of major breaks in the workflow. In a small number of cases support by system manufacturers remains necessary.

To analyse the image quality and diagnostic effectiveness of a new C-arm-based 3D imaging method (C-arm-CT) for intraoperative evaluation of screw osteosyntheses adjacent to a peripheral joint.Insertion of screws into four cadaveric specimens simulated the surgical treatment of talus neck fractures. Ten orthopedic surgeons and 10 radiologists evaluated X-ray, C-arm fluoroscopy, C-arm-CT and CT images.The best image quality was obtained with X-rays (p0.001), followed by C-arm fluoroscopy (2D) and CT, with the C-arm-CT (3D) being rated lowest (p0.001). The most correct diagnoses were obtained with CT and C-arm-CT (with no statistical difference between them), while C-arm-fluoroscopy was inferior (p0.001) and X-rays were the worst (p0.05).Even if the image quality of C-arm-CT is definitely inferior to that of CT, screw misplacements can be reliably detected using C-arm-CT. As compared to the current standard procedures (intraoperative fluoroscopy and postoperative radiography), C-arm-CT performed better. C-arm-CT is ideally suited to the intraoperative diagnosis of high-contrast inquiries like bone fragments and OS material, especially at the extremities. Coupling of the new 3D imaging to existing navigation systems is possible. C-arm-CT will support the further development and implementation of open and minimally invasive surgical procedures.

AIM The early stage of rheumatoid arthritis (RA) is primarily manifested in the soft tissue of the hand. Although ultrasound (US) is regarded as an important imaging process in diagnostic medicine, precise characterization of sonomorphological changes has not yet been undertaken. METHOD 20 patients with RA were examined with US. Two radiologists described semiquantitatively the characteristics of synovial changes in the hand in a consensus-based process and measured the synovial width. Statistical methods were used to determine whether the various synovial changes differed significantly and to identify the most frequent locations of changes. RESULTS On the basis of the significant differences in morphology and synovial width, it is possible to distinguish between unremarkable findings, pannus tissue and band-like synovitis. Pannus tissue is most frequently found on the finger flexor tendons (FFT), the metacarpophalangeal joints (MCP) and the tendon of M. extensor carpi ulnaris (ECU). Band-like synovitis exhibits an uncharacteristic distribution pattern with a slight propensity to favour these locations. CONCLUSION The FFT, MCP joints and ECU tendons are particularly important in systematic US screening of the hand for the purpose of establishing reliable evidence of inflammatory changes. Different stages of RA can be identified on the basis of the characteristic types of synovitis and the number of joints and tendons affected.

Ziel: Prospektive Evaluation des Stellenwertes der manganverstarkten MRT am offenen Niederfeldgerat im Nachweis fokaler maligner Leberlasionen im Vergleich zur Spiral CT-Arterioportographie (CTAP). Material und Methode: Im Rahmen einer Phase III-Studie konnten zunachst insgesamt 27 konsekutive Patienten in die Studie eingeschlossen werden. 7 Patienten erfullten im weiteren Verlauf nicht alle Einschlusskriterien und kamen nicht zur Auswertung. Bei allen Patienten wurden in einem Abstand von maximal 1 Woche eine native und eine manganverstarkte (MnDPDP) MRT der Leber bei 0,2 Tesla Feldstarke (Siemens Magnetom Open) sowie eine DSA mit unmittelbar folgender Spiral-CTAP (Siemens Somatom Plus 4) durchgefuhrt. Die Gesamtzahl und die nach Grose (a) 2 cm) aufgeschlusselte Anzahl der gefundenen Lasionen wurden verglichen. Bei der statistischen Auswertung kam der Vorzeichentest mit einem Signifikanzniveau von p 2 cm. For statistical evaluation, the sign test with a significance level of p < 0.05 was used. Results: CT AP depicted 114 lesions, whereas native MRI detected 62 and MnDPDP-enhanced MRI revealed 69 lesions. Significant differences were shown for collective comparison and for selective comparison of category (b), and of categories (a) and (b) combined. No significant differences were found between native and contrast-enhanced MRI. Conclusion: MnDPDP should be reserved for high-field strengths since low field strengths cannot be expected to confirm or exclude malignant liver lesions reliably.

Treatment with alfa-interferon alone yielded poor results in children with chronic hepatitis C and was not generally recommended. Owing to limited experience with combination therapy in children, the aim of the study was to evaluate the efficacy and tolerability of alfa-interferon 2b in combination with ribavirin in these patients with different routes of viral transmission. In an uncontrolled pilot study, 41 children and adolescents ranging from 3 to 16 years were treated with alfa-interferon at a dose of 3 or 5 MU/m2 3 times weekly in combination with oral ribavirin (15 mg/kg/d) for 12 months. The mode of infection was unknown in 4, parenterally transmitted in 16, and vertically transmitted in 21 children. Forty patients completed the study. Eleven children, who remained hepatitis C virus (HCV)-RNA positive 6 months after the beginning, discontinued therapy. One boy stopped treatment because of side effects. At the end of treatment 25 patients were HCV-RNA negative (61%). All individuals remained HCV-RNA negative during the 6-month follow-up period. Nine of 15 children with parenteral (56.3%), 14 of 21 with vertical (66.6%), and 2 of 4 with unknown route of infection responded. Side effects included minor clinical signs such as fever, flu-like symptoms, anorexia, and more severe signs (21.4%) such as the development of thyroid autoantibodies and impairment of thyroid function. In conclusion, combination of alfa-interferon with ribavirin seems to be an important advance in the treatment of chronic hepatitis C in children and adolescents. This also is true for both vertically infected patients and for individuals with normal transaminase levels before therapy. (HEPATOLOGY 2002;36:1280-1284.)

Purpose: Evaluation of 3D-CT imaging of the axial skeleton and different joints of the lower and upper extremities with a new dedicated CT system (ISO-C-3D) based on a mobile isocentric C-arm image amplifier. Material and Methods: 27 cadaveric specimes of different joints of the lower and upper extremities and of the spinal column were examined with 3D-CT imaging (ISO-C-3D). All images were evaluated by 3 radiologists for image quality using a semiquantitative score (score value 1: poor quality; score value 4: excellent quality). In addition, dose measurements and measurements of high contrast resolution were performed in comparison to conventional and low-dose spiral CT using a high contrast phantom (Catphan, Phantom Laboratories). Results: Adequate image quality (mean score values 3 - 4) could be achieved with an applied dose comparable to low-dose CT in smaller joints such as wrist, elbow, ankle and knee. A remarkably inferior image quality resulted in imaging of the hip, lumbar and thoracic spine (mean score values 2 - 3) in spite of almost doubling the dose (dose increased by 85 percent). The image quality of shoulder examinations was insufficient (mean score value 1). Phantom studies showed a high-contrast resolution comparable to helical CT in the xy-axis (9 lp/cm). Conclusion: Preliminary results show, that image quality of C-arm-based CT-imaging (ISO-C-3D) seems to be adequate in smaller joints. ISO-C-3D images of the hip and axial skeleton show a decreased image quality, which does not seem to be sufficient for diagnosing subtle fractures.

PURPOSE To analyze a prototype mobile C-arm 3D image amplifier in the detection and classification of experimental tibial condylar fractures with multiplanar reconstructions (MPR). METHOD Human knee specimens (n = 22) with tibial condylar fractures were examined with a prototype C-arm (ISO-C-3D, Siemens AG), plain films (CR) and spiral CT (CT). The motorized C-arm provides fluoroscopic images during a 190 degrees orbital rotation computing a 119 mm data cube. From these 3D data sets MP reconstructions were obtained. All images were evaluated by four independent readers for the detection and assessment of fracture lines. All fractures were classified according to the Muller AO classification. To confirm the results, the specimens were finally surgically dissected. RESULTS 97 % of the tibial condylar fractures were easily seen and correctly classified according to the Muller AO classification on MP reconstruction of the ISO-C-3D. There is no significant difference between ISO-C and CT in detection and correct classification of fractures, but ISO-CD-3D is significant by better than CR. CONCLUSION The evaluation of fractures with the ISO-C is better than with plain films alone and comparable to CT scans. The three-dimensional reconstruction of the ISO-C can provide important information which cannot be obtained from plain films. The ISO-C-3D may be useful in planning operative reconstructions and evaluating surgical results in orthopaedic surgery of the limbs.

Background: Arthroscopic procedures may be technically challenging because of impaired vision, limited space, and the 2-dimensional vision of a 3-dimensional structure. Spatial orientation may get more complicated when the camera is pointing toward the surgeon. Hypothesis: Spatial orientation and arthroscopic performance may be improved by simply mirroring the image on the monitor in different configurations regarding the position and orientation of camera and instrument. Study Design: Descriptive laboratory study. Methods: Thirty volunteers from an orthopaedic department were divided into 3 equal groups according to their arthroscopic experience (beginners, intermediates, seniors). All subjects were asked to perform a standardized task in a closed box mimicking an endoscopic space. The same task had to be performed in 4 different configurations regarding camera and instrument position and orientation (pointing toward or away from the subject) with either the original or mirrored image on the monitor. Efficiency (time per stick; TPS), precision (successful completion of the task), and difficulty rating using a visual analog scale (VAS) were analyzed. Results: Mirroring the image demonstrated no advantage over the original images in any configuration regarding TPS. Successful completion of the task was significantly better when the image was mirrored in the configuration with the camera pointing toward and the instrument away from the surgeon. There was a positive correlation between TPS and subjective VAS difficulty rating ( r = 0.762, P = .000) and a negative correlation between the successful completion of the task and VAS ( r = −0.515, P = .000). Conclusion: Mirroring the image may have a positive effect on arthroscopic performance of surgeons in certain configurations. A significantly improved performance was seen when the arthroscope was pointing toward and the grasping instrument pointing away from the subject. Mirroring the image may facilitate surgery in such clinical situations. Clinical Relevance: Mirroring the image may facilitate arthroscopic procedures in certain clinical situations.

We aimed to critically review our experience with the value and risks of a diagnostic hysteroscopy performed in addition to LLETZ. We retrospectively included 442 womentients undergoing LLETZ and additional routine diagnostic hysteroscopy. Women for whom concomitant diagnostic hysteroscopy was somehow indicated were excluded. We focused on complications and intrauterine abnormalities detected by hysteroscopy that had not been seen on preoperative vaginal ultrasound. In 28/442 (6.3%), hysteroscopy and/or histological examination of the specimen removed by curettage revealed an abnormal intrauterine finding (benign endometrial polyps, n=20; benign cervical polyps, n=2; small leiomyomas inside the uterine cavity, n=1; septate/arcuate/unicornuate, n=5). A total of 38 surgical complications (8.6%) occurred. The two adverse events related to diagnostic hysteroscopy were uterine perforations (0.5%). In conclusion, only a few benign findings of questionable clinical relevance were discovered. Thus, we do not consider an additional routine diagnostic hysteroscopy during LLETZ beneficial for the patient.

The creation of guidelines is one thing, and their implementation in everyday clinical practice is quite another (1, 2). The first guideline of the German Society of Pediatric Surgery on the treatment of undescended testis was published in 1999, remained current for a decade, and appeared in a newly revised version in January 2009 on the homepage of the Association of the Scientific Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF). The main change regarding treatment in the updated guideline was that the recommended time for surgical treatment (orchidopexy) was changed from before the affected child‘s second birthday to before his first birthday. The declared objective of treatment was the prevention of secondary testicular changes by early repositioning of the testis in the scrotum, in order to lower the risk of subfertility and testicular cancer in adulthood (3, 4). Newly available scientific knowledge had already led, in other countries, to a resetting of the optimal time for treatment to the child‘s first year of life (5). In April 2013, a further (and currently valid) revision of this guideline appeared on the AWMF homepage, containing no further major changes. In this issue of Deutsches Arzteblatt International, Hrivatakis et al. address the clinically important question of how well the guideline is now being implemented (6).

Results In human fetuses NOS3 expression directly correlated with 5-hydroxymethylcytosine levels as well as H3K9ac and H2A.Zac at the transcription start site. Using an in vitro model for placental dysfunction we confirmed the dynamic NOS3 response and histone acetylation patterns. Concomitantly we recognized massive turnover of Stat3 at a discrete binding site in the NOS3 promoter upon hypoxic conditions. Moreover, knock-down experiments targeting either STAT3 or NOS3 provided strong evidence for a functional NOS3 and STAT3 relationship. Interestingly, induced hyperacetylation and in vitro reporter assays showed that NOS3 expression becomes self-attenuated by co-expression of intronic 27nt-ncRNA modulating STAT3 signaling.

Objectives: To perform a prospective, blinded, randomized interventional trial in patients with recurrent abdominal pain. The primary endpoint was to determine the abdominal pain intensity after 2 weeks of fructose restricted diet. Secondary endpoints were changes of pain frequency and a secondary symptom score (SSS). Methods: 103 individuals with recurrent abdominal pain for more than 3 months were randomized. 51 patients were allocated to group A (diet) and 52 to group B (no diet). 2 weeks later the patients underwent hydrogen breath test and were assigned to the test positive or negative group to identify patients with fructose malabsorption. Results: 2 weeks after intervention the pain score decreased significantly from a median 5.5 in group A to 4 and did not change significantly in group B (5.3 to 5). In group A both patients with positive and negative breath tests had a significant lower pain score (−2 and −1.75, respectively). Frequency of abdominal pain decreased in both groups but without significant difference, SSS improved only in group A from median 6 to 3.5. Positive breath test was no predicting factor, neither was abdominal pain during the test. Conclusions: Fructose restricted diet in children and adolescents with recurrent abdominal pain may be of benefit to improve both abdominal pain symptoms and other secondary symptoms. Since a negative breath test result does not exclude a positive response to fructose restriction, the hydrogen breath test does not seem to be the appropriate diagnostic mean to predict the response to the diet.

Background Virus-host interactions result in altered gene expression profiles in host cell nuclei and enable virus particle production, thus obligatorily involving changes in their epigenomes. Neither such epigenome changes nor their response to antiviral treatment have been extensively studied to date, although viral infections are known to contribute to the long-term development of severe secondary diseases, for example, hepatocellular carcinoma. This may be causally linked to virus-induced persistent plastic chromatin deformations. Results We studied whether impaired hepatitis B virus (HBV) replication can lead to the restitution of epigenome signatures hypothesizing that hepatocytes alternatively could adopt a ‘memory’ state of the infection; that is, the chromatin could persist in a HBV-induced configuration potentially inheritable between dividing hepatocytes. We therefore determined epigenomic signatures and gene expression changes altered by HBV and the effects of suppressed HBV replication in nontransformed hepatocytes of newborn mice. Further we investigated differential histone acetyltransferase and histone deacetylase activities in HBV-negative and HBVpositive hepatocytes, as well as the effects of HBV suppression on gene expression and the chromatin landscape. We show that the expression of several genes and the chromatin landscape become altered upon HBV infection, including global hypoacetylation of H2A.Z and H3K9. Reporter assays monitoring the activities of histone acetyltransferases or histone deacetylases, respectively, suggest that hypoacetylation most probably depends on elevated sirtuin deacetylase activity, but not on class I/II histone deacetylases. Using Micrococcus nuclease to study the chromatin accessibility in met murine-D3 and hepatitis B virus met murine hepatocytes, we demonstrate that the observed differences in H2A.Z/H3K9 acetylation lead to global chromatin structure changes. At all selected sites examined by chromatin immunoprecipitation and quantitative real-time PCR, these effects can be partly restituted via the nucleoside analog reverse transcriptase inhibitor 3TC or using anti-HBV microRNA-like molecules. Conclusions Increased sirtuin activity might lead to global histone hypoacetylation signatures, which could contribute to the HBV-induced pathomechanism in nontransformed hepatocytes. Using several techniques to suppress HBV replication, we observed restituted gene expression and chromatin signature patterns reminiscent of noninfected hepatocytes. Importantly, ectopic expression of antiviral short-hairpin RNA, but not microRNA-like molecules, provoked intolerable off-target effects on the gene expression level. Electronic supplementary material The online version of this article (doi:10.1186/1868-7083-6-26) contains supplementary material, which is available to authorized users.

The purpose of this study was to compare cranial CT (CCT) image quality (IQ) of the MBIR algorithm with standard iterative reconstruction (ASiR).In this institutional review board (IRB)-approved study, raw data sets of 100 unenhanced CCT examinations (120 kV, 50-260 mAs, 20 mm collimation, 0.984 pitch) were reconstructed with both ASiR and MBIR. Signal-to-noise (SNR) and contrast-to-noise (CNR) were calculated from attenuation values measured in caudate nucleus, frontal white matter, anterior ventricle horn, fourth ventricle, and pons. Two radiologists, who were blinded to the reconstruction algorithms, evaluated anonymized multiplanar reformations of 2.5 mm with respect to depiction of different parenchymal structures and impact of artefacts on IQ with a five-point scale (0: unacceptable, 1: less than average, 2: average, 3: above average, 4: excellent).MBIR decreased artefacts more effectively than ASiR (p0.01). The median depiction score for MBIR was 3, whereas the median value for ASiR was 2 (p0.01). SNR and CNR were significantly higher in MBIR than ASiR (p0.01).MBIR showed significant improvement of IQ parameters compared to ASiR. As CCT is an examination that is frequently required, the use of MBIR may allow for substantial reduction of radiation exposure caused by medical diagnostics.• Model-Based iterative reconstruction (MBIR) effectively decreased artefacts in cranial CT. • MBIR reconstructed images were rated with significantly higher scores for image quality. • Model-Based iterative reconstruction may allow reduced-dose diagnostic examination protocols.

To evaluate the potential of phase-contrast computed tomography (CT) for atherosclerotic plaque imaging in human carotid arteries in an experimental ex vivo study.The study was approved by the institutional review board, and informed consent was obtained from the patients' relatives. Seven postmortem human carotid artery specimens were imaged at a laboratory setup by using a conventional x-ray tube and grating interferometer. After histologic processing, phase-contrast imaging and histopathologic data were matched. Characteristics of the necrotic core (NC) covered by a fibrous cap (FC), intraplaque hemorrhage (IPH), and calcifications (CAs) were established, and sensitivity, specificity, and accuracy of phase-contrast CT for plaque detection and the potential for accurate quantification were assessed. The Cohen κ and Pearson correlation coefficient R were used to determine the agreement between phase-contrast imaging and histopathologic findings for plaque characterization and correlation of quantitative plaque measurements, respectively. A difference with a P value of less than .05 was considered significant.Characteristic criteria were found in all analyzed plaque components. Applying these criteria, phase-contrast CT had a good sensitivity for the detection of the FC and NC, IPH, and CAs (all,80%) and excellent specificity and accuracy (all,90%), with good interreader agreement (κ ≥ 0.72, P.0001). There were excellent correlations for quantitative measurements of FC, NC, and CAs between phase-contrast imaging and histopathologic findings (R ≥ 0.92). Interreader reproducibility was excellent, with an intraclass correlation coefficient of 0.98 or higher for all measurements.The results of this study indicate that ex vivo phase-contrast CT can help identify and quantify atherosclerotic plaque components, with excellent correlation to histopathologic findings. Although not yet applicable in vivo, phase-contrast CT may become a valuable tool to monitor atherosclerotic disease process noninvasively.

Die technische Gebäudeausrüstung nimmt einen immer breiteren Raum bei der Errichtung von Neubauten und der Altbausanierung ein. Aktuelle Themen wie die Energieeffizienz (Heizung, Trinkwassererwärmung und Raumlufttechnik) und die Hygiene (Trinkwasser und Raumlufttechnik) haben heute neben traditionellen Themen wie z. B. Schallschutz, Geruchsbelästigungen, beheizte Fußbodenkonstruktionen und Schutz vor Korrosions- und Steinschäden einen festen Platz in der Gebäudeplanung und -ausführung eingenommen. Gleichzeitig hat sich die Anzahl der Schnittstellen der technischen Gebäudeausrüstung zu den Hochbaugewerken vervielfacht. Im selben Maß ist auch die fachliche Zuständigkeit der Architekten, Bauingenieure und Bausachverständigen für Schäden an und durch Installationsanlagen gestiegen. Ohne ausreichendes Wissen über die technische Gebäudeausrüstung kann die Planung und Objektüberwachung durch einen Architekten oder Bauingenieur heute Schäden an und durch Installationsanlagen nicht vermeiden. Das vorliegende Buch bietet einen Überblick über den derzeitigen Stand der Technik unter Einbeziehung der aktuellen Normung und richtet sich an Architekten, Bauingenieure und Bausachverständige. Es erläutert in allgemein verständlicher Weise die wesentlichen Grundzüge der technischen Gebäudeausrüstung und zeigt die wichtigen Schnittstellen zu den Gewerken des Hochbaus auf.

PURPOSE: To determine the lower limit of dose reduction with hybrid and fully iterative reconstruction algorithms in detection of endoleaks and in-stent thrombus of thoracic aorta with computed tomographic (CT) angiography by applying protocols with different tube energies and automated tube current modulation. MATERIALS AND METHODS: The calcification insert of an anthropomorphic cardiac phantom was replaced with an aortic aneurysm model containing a stent, simulated endoleaks, and an intraluminal thrombus. CT was performed at tube energies of 120, 100, and 80 kVp with incrementally increasing noise indexes (NIs) of 16, 25, 34, 43, 52, 61, and 70 and a 2.5-mm section thickness. NI directly controls radiation exposure; a higher NI allows for greater image noise and decreases radiation. Images were reconstructed with filtered back projection (FBP) and hybrid and fully iterative algorithms. Five radiologists independently analyzed lesion conspicuity to assess sensitivity and specificity. Mean attenuation (in Hounsfield units) and standard deviation were measured in the aorta to calculate signal-to-noise ratio (SNR). Attenuation and SNR of different protocols and algorithms were analyzed with analysis of variance or Welch test depending on data distribution. RESULTS: Both sensitivity and specificity were 100% for simulated lesions on images with 2.5-mm section thickness and an NI of 25 (3.45 mGy), 34 (1.83 mGy), or 43 (1.16 mGy) at 120 kVp; an NI of 34 (1.98 mGy), 43 (1.23 mGy), or 61 (0.61 mGy) at 100 kVp; and an NI of 43 (1.46 mGy) or 70 (0.54 mGy) at 80 kVp. SNR values showed similar results. With the fully iterative algorithm, mean attenuation of the aorta decreased significantly in reduced-dose protocols in comparison with control protocols at 100 kVp (311 HU at 16 NI vs 290 HU at 70 NI, P ≤ .0011) and 80 kVp (400 HU at 16 NI vs 369 HU at 70 NI, P ≤ .0007). CONCLUSION: Endoleaks and in-stent thrombus of thoracic aorta were detectable to 1.46 mGy (80 kVp) with FBP, 1.23 mGy (100 kVp) with the hybrid algorithm, and 0.54 mGy (80 kVp) with the fully iterative algorithm.