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1Latest Papers from Table of Contents or Articles in PressM. W. Carroll ; D. A. Matthews ; J. A. Hiscox ; M. J. Elmore ; G. Pollakis ; A. Rambaut ; R. Hewson ; I. Garcia-Dorival ; J. A. Bore ; R. Koundouno ; S. Abdellati ; B. Afrough ; J. Aiyepada ; P. Akhilomen ; D. Asogun ; B. Atkinson ; M. Badusche ; A. Bah ; S. Bate ; J. Baumann ; D. Becker ; B. Becker-Ziaja ; A. Bocquin ; B. Borremans ; A. Bosworth ; J. P. Boettcher ; A. Cannas ; F. Carletti ; C. Castilletti ; S. Clark ; F. Colavita ; S. Diederich ; A. Donatus ; S. Duraffour ; D. Ehichioya ; H. Ellerbrok ; M. D. Fernandez-Garcia ; A. Fizet ; E. Fleischmann ; S. Gryseels ; A. Hermelink ; J. Hinzmann ; U. Hopf-Guevara ; Y. Ighodalo ; L. Jameson ; A. Kelterbaum ; Z. Kis ; S. Kloth ; C. Kohl ; M. Korva ; A. Kraus ; E. Kuisma ; A. Kurth ; B. Liedigk ; C. H. Logue ; A. Ludtke ; P. Maes ; J. McCowen ; S. Mely ; M. Mertens ; S. Meschi ; B. Meyer ; J. Michel ; P. Molkenthin ; C. Munoz-Fontela ; D. Muth ; E. N. Newman ; D. Ngabo ; L. Oestereich ; J. Okosun ; T. Olokor ; R. Omiunu ; E. Omomoh ; E. Pallasch ; B. Palyi ; J. Portmann ; T. Pottage ; C. Pratt ; S. Priesnitz ; S. Quartu ; J. Rappe ; J. Repits ; M. Richter ; M. Rudolf ; A. Sachse ; K. M. Schmidt ; G. Schudt ; T. Strecker ; R. Thom ; S. Thomas ; E. Tobin ; H. Tolley ; J. Trautner ; T. Vermoesen ; I. Vitoriano ; M. Wagner ; S. Wolff ; C. Yue ; M. R. Capobianchi ; B. Kretschmer ; Y. Hall ; J. G. Kenny ; N. Y. Rickett ; G. Dudas ; C. E. Coltart ; R. Kerber ; D. Steer ; C. Wright ; F. Senyah ; S. Keita ; P. Drury ; B. Diallo ; H. de Clerck ; M. Van Herp ; A. Sprecher ; A. Traore ; M. Diakite ; M. K. Konde ; L. Koivogui ; N. Magassouba ; T. Avsic-Zupanc ; A. Nitsche ; M. Strasser ; G. Ippolito ; S. Becker ; K. Stoecker ; M. Gabriel ; H. Raoul ; A. Di Caro ; R. Wolfel ; P. Formenty ; S. Gunther
Nature Publishing Group (NPG)
Published 2015Staff ViewPublication Date: 2015-06-18Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsPublished by: -
2Articles: DFG German National LicensesStaff View
ISSN: 0375-9601Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
3Articles: DFG German National LicensesStaff View
ISSN: 0375-9601Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesStaff View
ISSN: 0375-9601Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesStaff View
ISSN: 0378-4371Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesStaff View
ISSN: 1434-601XSource: Springer Online Journal Archives 1860-2000Topics: PhysicsNotes: Abstract Employing perturbation theory aK +-meson proton potential resulting from two-pion exchange is obtained. Recoil effects are taken into account. For short distances we add a phenomenological hard core interaction and calculates-wave phase shifts.Type of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesStaff View
ISSN: 1434-6036Source: Springer Online Journal Archives 1860-2000Topics: PhysicsNotes: Abstract We calculate the influence of the elastic lattice on the orientational order-disorder transition in fcc solid ortho-hydrogen. The angular momentaJ = 1 of the molecules are coupled by quadrupole-quadrupole interaction which we reduce within the space group Pa 3 to the Ising model approximation. Local mechanical equilibrium requires the lattice to adjust itself to the forces caused by the inhomogeneous fluctuations in the angular momentum configuration. Following Wagner [6] this results in a 4-angular-momentum interaction with long range and short range contributions depending on the one-phonon Green function of the lattice. We use a Debye phonon spectrum and the molecular field approximation in order to obtain numerical results. According to the first order nature of the phase transition we get a pressure drop at the critical pointT c of 9.7 bar. The experimental value is estimated to be 8 bar. Compared to the rigid lattice the phase transition on the elastic lattice is smoothed out by the short range contribution. This corresponds to a reduction of the discontinuity of the order parameter at the critical pointT c by about 13%. The phase transition will vanish completely if we increase the magnitude of the short range terms by a factor of three.Type of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesStaff View
ISSN: 1432-1084Keywords: Key words: CT ; Pulmonary coin lesion ; Diagnostic errors ; Observer variationSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Abstract. The aim of this study was to assess interobserver variability in size determination of pulmonary nodules at spiral CT. Twenty-three patients with known pulmonary nodules (diameter 2–40 mm, mean diameter 7 mm) underwent spiral chest CT (collimation 5 mm, pitch 1). Images were reconstructed at 3- and 5-mm intervals (RI). Hard copies were analyzed by two radiologists who recorded every nodule with regard to location, diagnostic confidence (“definite,”“probable”) and nodule size in increments of 1 mm with specific attention to correct classification into one of three size classes (≤ 5 mm, 6–10 mm, 〉 10 mm). Interobserver variability was determined with Pearson's correlation coefficient and k measure. Of a total of 286 nodules, 103 nodules were found accordingly by both readers at 3 mm RI, and 96 at 5 mm RI. There was a good correlation of measurements (in millimeters) between both readers (Pearson's correlation coefficient: 0.89–0.95). Interobserver variability in categories was good at both reconstruction intervals (k: 0.61 at 3 mm, 0.74 at 5 mm RI) and very good (0.81) at 5 mm RI when uncertain nodules were excluded. Spiral CT allows reproducible size determination of pulmonary nodules as shown by good interobserver agreement in exact size measurement and categorization into three size classes.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesGißler, H. M. ; Roos, N. ; Diederich, S. ; Thomas, M. ; Schmid, K. W. ; Peters, P. E.
Springer
Published 1996Staff ViewISSN: 1432-2102Keywords: Schlüsselwörter Bronchiolitis obliterans mit organisierender Pneumonie ; BOOP ; Thoraxübersichtsaufnahme ; Computertomographie ; Key words Bronchiolitis obliterans with organizing pneumonia (BOOP) ; Chest radiography ; Computed tomographySource: Springer Online Journal Archives 1860-2000Topics: MedicineDescription / Table of Contents: Summary Bronchiolitis obliterans with organizing pneumonia (BOOP) is a clinicopathological syndrome of unknown etiology. Histopathologically, it is characterized by plugs of fibroplastic connective tissue within respiratory bronchioles, mononuclear cell infiltrates in parenchyma adjacent to the affected bronchioles and foam cells within alveolar airspaces. The disease usually presents as a subacute illness with complete resolution. A subset of BOOP, however, is associated with a fulminant course and a high lethality due to respiratory failure. Early diagnosis and therapy are mandatory. Chest radiography, computed tomography (CT), bronchoalveolar lavage (BAL) and open lung biopsy are the primary diagnostic techniques. Radiographically, BOOP is characterized by patchy areas of consolidation that are usually bilateral, peripheral and often migratory. In some cases small, round opacities may be observed as the only abnormality. CT can show the pattern of ground glass opacities, areas of airspace consolidation and small, round opacities, while considerable fibrotic change is usually not seen. A reticular roentgenographic pattern, fibrotic changes mainly in subpleural location at CT, lack of lymphocytosis in BAL fluid and histological features of usual interstitial pneumonitis and BOOP in biopsy specimens are all considered risk factors for a fatal outcome.Notes: Zusammenfassung Die Bronchiolitis obliterans mit organisierender Pneumonie (BOOP) ist eine klinisch-pathologisch definierte Lungenerkrankung oft ungeklärter Ätiologie, histologisch gekennzeichnet durch proliferierendes Granulationsgewebe in den respiratorischen Bronchiolen sowie interstitielle mononukleäre Zellinfiltrate und Schaumzellen in den Alveolen. Meist nimmt sie einen blanden Verlauf und hat eine günstige Prognose. Doch auch fulminante Verläufe mit letalem Ausgang sind beschrieben. Eine frühzeitige Diagnosestellung und Therapieeinleitung bestimmen wesentlich den Behandlungserfolg. Eckpfeiler der Diagnostik sind Übersichtsaufnahme und Computertomographie des Thorax, bronchoalveoläre Lavage (BAL) und Lungenbiopsie. Die Thoraxübersichtsaufnahme zeigt typischerweise bipulmonale, periphere, kleinfleckig-konfluierende Verschattungen, oft mit einer Migrationstendenz. Computertomographisch finden sich kleinfleckige, milchglasartige oder konsolidierende Verschattungen jeweils allein oder in Kombination, ohne daß wesentliche fibrotische Veränderungen nachweisbar sind. Ein retikuläres Verschattungsmuster in der Thoraxübersichtsaufnahme, subpleurale Fibroseherde in der CT, fehlende Lymphozytose in der BAL und der histologische Nachweis einer intraluminalen und interstitiellen Entzündungskomponente mit unterschiedlichen Fibrosestadien im Sinne einer kryptogenen fibrosierenden Alveolitis gelten als prädiktive Faktoren für einen ungünstigen Verlauf der BOOP. Bei antibiotikarefraktären Infiltraten sollte an die Verdachtsdiagnose einer BOOP gedacht werden und gegebenenfalls eine histologische Untersuchung erfolgen.Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesStaff View
ISSN: 1432-2102Keywords: Schlüsselwörter Bronchiektasen ; Thoraxübersichtsaufnahme ; Bronchographie ; Computertomographie ; HRCT ; Key words Bronchiectasis ; Chest radiography ; Bronchography ; Computed tomographySource: Springer Online Journal Archives 1860-2000Topics: MedicineDescription / Table of Contents: Summary Various diseases can cause bronchiectasis as a result of inflammatory bronchial wall damage. The diagnosis is based on imaging techniques, which are also required to assess the extent and localization of dilated bronchi and possible causes. Chest radiography only occasionally allows the diagnosis of bronchiectasis (Fig. 2) and is usually not a sufficient basis for therapeutic decisions (Fig. 1 a), but it is important for follow-up studies. Bronchography (Fig. 1 b) was considered the diagnostic procedure of choice in suspected bronchiectasis for decades. Being an invasive procedure, it has recently been almost completely replaced by computed tomography (CT), which can also demonstrate associated pulmonary abnormalities (Fig. 6) in addition to visualizing the bronchi. CT diagnosis of bronchiectasis is based on the demonstration of bronchial dilatation relative to the adjacent pulmonary artery (Figs. 4, 5, 7–9), lack of bronchial tapering (Figs. 3, 4, 10) and visualization of bronchi in the lung periphery (Figs. 3, 5, 8, 10). In suspected bronchiectasis high-resolution scans should be obtained during inspiration. Contiguous, thicker slices or scans taken during expiration may be required in particular cases.Notes: Zusammenfassung Bronchiektasen entstehen im Rahmen unterschiedlicher Erkrankungen durch inflammatorische Schädigung der Bronchialwand. Sie werden im wesentlichen mittels bildgebender Verfahren diagnostiziert, die auch erforderlich sind, um Ausmaß, Lokalisation, mögliche Ursachen und Begleitveränderungen darzustellen. Die Thoraxübersichtsaufnahme erlaubt nur in wenigen Fällen eine eindeutige Diagnose und reicht in der Regel zur Therapieplanung nicht aus. In der Verlaufskontrolle von Komplikationen besitzt sie dagegen einen hohen Stellenwert. Die Bronchographie galt über Jahrzehnte als Verfahren der Wahl in der Bronchiektasendiagnostik, wurde aber wegen ihrer Invasivität in den letzten Jahren durch die Computertomographie weitgehend ersetzt. Diese kann neben der bronchialen Dilatation auch assoziierte Veränderungen des Lungenparenchyms darstellen. Die computertomographische Diagnose von Bronchiektasen beruht auf dem Nachweis einer fehlenden Verjüngung des Bronchus sowie seiner Dilatation im Vergleich mit der begleitenden Pulmonalarterie. Auch der Nachweis von Bronchien in der Lungenperipherie gilt als wichtiges Kriterium. Die Untersuchung sollte mit hochauflösenden Schichten in Inspiration erfolgen; dickere Schichten sowie Exspirationsaufnahmen können unter bestimmten Umständen nützlich sein.Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesDiederich, S. ; Roos, N. ; Schmitz-Linneweber, B. ; Gaubitz, M. ; Peters, P. E.
Springer
Published 1996Staff ViewISSN: 1432-2102Keywords: Schlüsselwörter HRCT ; Kollagenosen ; Progressive Systemsklerose ; Systemischer Lupus erythematodes ; Rheumatoide Arthritis ; Key words HRCT ; Collagen vascular diseases ; Progressive systemic sclerosis ; Systemic lupus erythematosus ; Rheumatoid arthritisSource: Springer Online Journal Archives 1860-2000Topics: MedicineDescription / Table of Contents: Summary Collagen vascular diseases, representing systemic soft tissue disorders, may cause a broad spectrum of pathologic changes of the respiratory tract. The type and extent of manifestations can vary considerably among individuals and entities. This survey describes the chest radiographic and, in particular, high-resolution computed tomographic (HRCT) findings of individual lesions of the respiratory tract. It includes fibrosing alveolitis (alveolitis, interstitial pneumonia, pulmonary fibrosis) and bronchial (bronchitis/bronchiolitis, bronchiectasis), pleural and vascular manifestations, as well as lymphadenopathy and abnormalities related to therapy. We present typical patterns of changes in progressive systemic sclerosis (PSS, scleroderma), systemic lupus erythematosus (SLE), mixed connective tissue disease (MCTD, Sharp syndrome), Sjögren syndrome, overlap syndrome and rheumatoid arthritis (RA). Furthermore, we describe findings which are specific for individual entities such as esophageal involvement in PSS, acute pneumonitis and pulmonary hemorrhage in SLE, lymphoproliferative disease in Sjögren syndrome and necrobiotic nodules in RA.Notes: Zusammenfassung Die Kollagenosen können als systemische Bindegewebserkrankungen auch zu einem breiten Spektrum pathologischer Veränderungen am Respirationstrakt führen, wobei sich Art und Ausmaß der Manifestationen innerhalb einzelner Entitäten und zwischen verschiedenen Krankheitsbildern erheblich unterscheiden können. In der vorliegenden Übersicht werden die entsprechenden Befunde von Thoraxübersichtsaufnahme und insbesondere hochauflösender Computertomographie (HRCT) beschrieben. Berücksichtigt werden dabei die fibrosierende Alveolitis (Alveolitis, interstitielle Pneumonie, Lungenfibrose), bronchiale (Bronchitis/Bronchiolitis, Bronchiektasen), pleurale und vaskuläre Manifestationen sowie Lymphadenopathie und therapieinduzierte Befunde. Typische Befundmuster bei progressiver Systemsklerose (PSS, Sklerodermie), systemischem Lupus erythematodes (SLE), „mixed connective tissue disease“ (MCTD, Sharp-Syndrom), Sjögren-Syndrom, Mischkollagenose („Overlap“syndrom) und rheumatoider Arthritis (RA) werden dargestellt. Außerdem werden für die einzelnen Krankheitsbilder jeweils spezifische Phänomene erläutert wie die Ösophagusbeteiligung bei PSS, akute Pneumonitis oder pulmonale Hämorrhagie bei SLE, lymphoproliferative Erkrankungen beim Sjögren-Syndrom und nekrobiotische Rundherde bei RA.Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesStaff View
ISSN: 1432-2102Keywords: Schlüsselwörter Computertomographie ; Pitch ; Äquivalentdosis ; TLD ; Konversionsfaktoren ; Effektive Dosis ; Key words Computed tomography ; Equivalent dose in man ; Thermoluminescence dosimetry ; Conversion factorsSource: Springer Online Journal Archives 1860-2000Topics: MedicineDescription / Table of Contents: Summary Computed tomography accounts for a high percentage of the populations exposure to radiation. Every possible means of reducing patient exposure must be considered. Exposure reduction will be most appropriate for organs with large absorption differences, since the accompanying decrease in signal-to-noise ratio will have a smaller effect. It has been shown in the literature that high-contrast details in the lung can be depicted, even with the lowest exposure rates. Therefore, experimental data are presented by means of thermoluminescence dosimetry and calculations using conversion factors to determine the technical parameters to be adopted for achieving the effective equivalent dose close to that of a conventional chest X-ray in two projections. With helical CT (pitch 2, 50 mAs, 120 kV, 5-mm slice thickness) it was possible to reduce the equivalent dose from 9.6 mSv to 0.6 mSv, which is comparable with the exposure in a conventional chest X-ray, measured to be 0.2 mSv.Notes: Zusammenfassung Die Computertomographie trägt zu einem hohen Prozentsatz zur Strahlenexposition der Bevölkerung bei. Es muß daher jeder Ansatz verfolgt werden, der eine Reduktion der Dosis möglich erscheinen läßt. Für Organbereiche mit großen Absorptionsunterschieden wird dies am ehesten möglich sein, da das mit einer Dosisreduktion abnehmende Signal-Rausch-Verhältnis hier nur einen geringen Einfluß besitzt. Experimentelle Untersuchungen haben in der Vergangenheit gezeigt, daß die Hochkontrastdetails der Lunge auch mit niedrigen Dosiswerten darstellbar sind. Es wurde daher mittels Messungen mit Thermolumineszenzdosimetern und Berechnungen über Konversionsfaktoren untersucht, mit welchen Technikfaktoren man sich in befriedigender Art und Weise der effektiven Äquivalentdosis einer konventionellen Thoraxuntersuchung in 2 Ebenen nähern kann. Mit einem Spiral-CT (Pitch 2, 50 mAs, 120 kV, 5 mm Schichtdicke) konnte die effektive Dosis von bis zu 9,6 mSv auf 0,6 mSv reduziert werden. Für die konventionelle Thoraxuntersuchung konnte ein Wert von 0,2 mSv ermittelt werden.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesStaff View
ISSN: 1432-2102Keywords: Schlüsselwörter Hochauflösende Computertomographie ; Lunge ; Phänomenologie ; Differentialdiagnose ; Indikationen ; klinischer Stellenwert ; Key words High-resolution computed tomography ; Lung ; Findings ; Differential diagnosis ; Indications ; Clinical valueSource: Springer Online Journal Archives 1860-2000Topics: MedicineDescription / Table of Contents: Summary High-resolution computed tomography (HRCT) has proved to be the imaging technique of choice for the lung in numerous studies, allowing precise depiction of normal pulmonary anatomy – including the lobular architecture – as well as relevant pathologic changes. Its sensitivity, specificity and accuracy in this respect are markedly superior, not only to chest radiography, but also to conventional CT. Guidelines for standardized assessment and interpretation of HRCT findings have not been established in the German literature. The purpose of this paper was to develop a systematic classification of pulmonary HRCT findings based on the appearance of morphologic abnormalities (descriptive classification) and their relationship to anatomic structures of pulmonary parenchyma (anatomic classification). Reticular, nodular, and non-reticular/non-nodular densities, as well as lucencies, can be differentiated. Abnormalities of the pleural space are discussed separately. Following the presentation of typical CT findings, morphologic correlation and differential diagnosis are discussed. In addition, we point out indications and specific features of the clinical value of the technique.Notes: Zusammenfassung Die hochauflösende Computertomographie (HRCT) hat sich in zahlreichen Studien als bildgebendes Verfahren der Wahl für eine subtile Abbildung der regulären Lungenanatomie – und dabei vor allem ihrer lobulären Architektur – sowie für die Erkennung relevanter krankheitsassoziierter Lungenveränderungen bewährt. Ihre Sensitivität, Spezifität und Treffsicherheit ist diesbezüglich nicht nur im Vergleich zur Thoraxübersichtsaufnahme, sondern auch zur konventionellen CT deutlich überlegen. Da Richtlinien zur standardisierten Beschreibung und Interpretation entsprechender Befunde bisher im deutschsprachigen Schrifttum nicht etabliert wurden, versucht die vorliegende Arbeit, eine an Erscheinungsbild morphologischer Auffälligkeiten (deskriptive Klassifizierung) und deren Zuordnung zu definierten Leitstrukturen des Lungenparenchyms (pathoanatomische Klassifizierung) orientierte Systematik der pulmonalen HRCT-Phänomenologie zu konzipieren. Als Läsionsmuster der Lunge werden retikuläre, noduläre und nichtretikuläre – nichtnoduläre Verschattungen sowie Parenchymaufhellungen differenziert, während die Betrachtung von Veränderungen der Pleura gesondert erfolgt. Im Anschluß an die Darstellung der jeweiligen HRCT-Zeichen findet sich eine Erörterung ihrer Morphologiekorrelation und Differentialdiagnose. Darüber hinaus wird auf Indikationen und wichtige Aspekte des klinischen Stellenwerts dieses Verfahrens hingewiesen.Type of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesDetection of pulmonary nodules with overlapping vs non-overlapping image reconstruction at spiral CTStaff View
ISSN: 1432-1084Keywords: Key words: Lung ; Nodule ; Helical CT ; Image processingSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Abstract. The aim of this study was to analyze whether overlapping image reconstruction increases numbers of pulmonary nodules detected at helical CT. Forty-eight helical CT scans (21with a slice thickness of 10 mm; 27 with a slice thickness of 5 mm) of patients with known pulmonary nodules were reconstructed both with overlapping and non-overlapping image reconstruction. Two readers recorded number and size of pulmonary nodules as well as diagnostic confidence. With overlapping image reconstruction each reader diagnosed more pulmonary nodules (slice thickness 10 mm: +24.0 and +26.7 %, both p 〈 0.01; slice thickness 5 mm: +9.5 and +11.9 %, both not significant) and more “definite” nodules (slice thickness 10 mm: +20.3 %, p 〈 0.05, and +30.8 %, p 〈 0.005; slice thickness 5 mm: +18.0 and +17.0 %, both p 〈 0.05). Nodules diagnosed with overlapping image reconstruction only were almost exclusively smaller than the slice thickness. The increase in number of nodules detected was not associated with a decrease in diagnostic confidence. Overlapping image reconstruction improves detection of pulmonary nodules smaller than the slice thickness at spiral CT.Type of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesStaff View
ISSN: 1432-1084Keywords: Bronchiectasis ; High-resolution computed tomography ; Thin-section CT ; Bronchi ; Diagnostic radiology ; Observer performanceSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Abstract The purpose of our study was to determine interobserver variation in the analysis of high-resolution computed tomography (HRCT) in the lungs of patients with clinically suspected bronchiectasis. HRCT scans of 88 patients were analysed independently by three radiologists with variable experience in thoracic radiology using a subjective scoring system to record bronchi as normal, mildly abnormal or severely abnormal. The presence, severity and distribution of bronchial dilatation and bronchial wall thickening were recorded. Kappa values were calculated for assessment of interobserver agreement. Agreement between the three readers was good for the detection of bronchiectasis (kappa 0.78) and assessment of its severity (0.68), detection of bronchial wall thickening (0.64) and moderately good for the assessment of its severity (0.58) on a per-patient basis. When individual lobes were analysed, agreement was moderately good for the detection of abnormal bronchi (0.59). Agreement on the extent of abnormal bronchi using five categories was only fair (0.39), but was good when differences of one category were ignored (0.63). Interobserver variation with HRCT in suspected bronchiectasis appears satisfactory for comparative studies.Type of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesStaff View
ISSN: 1432-1084Keywords: Key words: Lung transplantation ; Aspergillosis ; CT ; Chest radiographySource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Abstract. The objective of our study was to assess radiographic and CT findings in lung transplant patients with evidence of Aspergillus colonization or infection of the airways and correlate the findings with clinical, laboratory, bronchoalveolar lavage, biopsy and autopsy findings. The records of 189 patients who had undergone lung transplantation were retrospectively reviewed for evidence of Aspergillus colonization or infection of the airways. Aspergillus was demonstrated by culture or microscopy of sputum or bronchoalveolar lavage fluid or histologically from lung biopsies or postmortem studies in 44 patients (23 %). Notes and radiographs were available for analysis in 30 patients. In 12 of the 30 patients (40 %) chest radiographs remained normal. In 11 of 18 patients with abnormal radiographs pulmonary abnormalities were attributed to invasive pulmonary aspergillosis (IPA) in the absence of other causes for pulmonary abnormalities (8 patients) or because of histological demonstration of IPA (3 patients). In these 11 patients initial radiographic abnormalities were focal areas of patchy consolidation (8 patients), ill-defined pulmonary nodules (2 patients) or a combination of both (1 patient). In some of the lesions cavitation was demonstrated subsequently. At CT a “halo” of decreased density was demonstrated in some of the nodules and lesion morphology and location were shown more precisely. Demonstration of Aspergillus from the respiratory tract after lung transplantation does not necessarily reflect IPA but may represent colonization of the airways or semi-invasive aspergillosis. The findings in patients with IPA did not differ from those described in the literature in other immunocompromised patients, suggesting that surgical disruption of lymphatic drainage and nervous supply or effects of preservation and transport of the transplant lung do not affect the radiographic appearances.Type of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesDiederich, S. ; Lenzen, H. ; Puskas, Z. ; Koch, A. T. ; Yelbuz, T. M. ; Eameri, M. ; Roos, N. ; Peters, P. E.
Springer
Published 1996Staff ViewISSN: 1432-2102Keywords: Schlüsselwörter Computertomographie ; Lunge ; Niedrigdosis-CT ; Strahlenexposition ; Rundherd ; Key words Computed tomography ; Lung ; Low-Dose CT ; Radiation exposure ; Pulmonary noduleSource: Springer Online Journal Archives 1860-2000Topics: MedicineDescription / Table of Contents: Summary Introduction. Computed tomography is a significant source of medical radiation exposure for populations in Europe. Reduced radiation exposure may be possible with modern CT scanners with an image quality that while less good than before remains acceptable for clinical purposes. The lung appears particularly well suited to investigation with low-dose CT owing to the high contrast between normal and diseased pulmonary parenchyma. Methods. We analysed the diagnostic accuracy of different low-dose CT protocols for the detection of pulmonary nodules using inflation-fixed isolated postmortem lung specimens in a chest phantom. In a comparative patient study diagnostic accuracies of standard-dose CT (120 kV, 250 mAs; slice thickness 10 mm, pitch 1) and low-dose CT (120 or 140 kV, 50 mAs; slice thickness 5 or 10 mm, pitch 1 or 2) were assessed. Results. Preliminary results suggest that low-dose CT protocols with radiation exposure of 10–20 % of that with standard-dose CT can reliably depict soft tissue density pulmonary nodules with a diameter of more than 5 mm and can also demonstrate smaller nodules equally well in many cases. Conclusions. Low-dose CT may frequently be an adequate imaging procedure in a given clinical setting, particularly in young patients with benign disease.Notes: Zusammenfassung Die Computertomographie (CT) trägt wesentlich zur medizinischen Strahlenexposition der Bevölkerung bei. Eine Reduktion dieser Strahlenexposition läßt sich vermutlich mit modernen CT-Geräten bei für viele Fragestellungen vertretbaren Einschränkungen der Bildqualität realisieren. Zur Untersuchung mittels solcher Niedrigdosis-CT (NDCT) erscheint die Lunge aufgrund der günstigen Kontrastverhältnisse des normalen und pathologischen Parenchyms besonders geeignet. Wir untersuchten die Treffsicherheit unterschiedlicher NDCT-Protokolle im Nachweis pulmonaler Rundherde an Lungenpräparaten in einem Thoraxphantom. In einer vergleichenden Patientenstudie wurde die Treffsicherheit der Spiral-CT des Thorax mit etablierten Parametern (120 kV, 250 mAs, Schichtdicke 10 mm, Pitch 1) mit derjenigen verschiedener NDCT-Protokolle (120 oder 140 kV, 50 mAs, Schichtdicke 5 oder 10 mm, Pitch 1 oder 2) verglichen. Vorläufige Ergebnisse zeigen, daß diese NDCT-Protokolle mit einer Dosis von 10 bis 20 % der Standard-Dosis CT weichteildichte Lungenrundherde mit einem Durchmesser von mehr als 5 mm zuverlässig nachweisen konnten und auch bei kleineren Rundherden häufig gleichwertig waren. Abhängig von der Fragestellung sollten derartige NDCT-Protokolle v. a. bei jungen Individuen mit benignen Erkrankungen auch in der klinischen Routine eingesetzt werden.Type of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesStaff View
ISSN: 1434-6036Source: Springer Online Journal Archives 1860-2000Topics: PhysicsNotes: Abstract A learning mechanism for neural networks with binary synapses is defined and investigated. The algorithm is based on minimizing the energy of an Ising model. A replica symmetric calculation gives a parameter range where perfect learning is possible. A simple descent algorithm is studied by numerical simulation; and storage capacities, learning times and basins of attraction are determined.Type of Medium: Electronic ResourceURL: