[Differential diagnoses of biliary tract diseases : Computed tomography and magnetic resonance imaging]. / Differenzialdiagnosen von Gallenwegerkrankungen : Computertomographie und Magnetresonanztomographie.

CLINICAL/METHODICAL ISSUE: Bile duct diseases can be found in all age groups and show an increased prevalence in northern Europe. Pathologies range from benign diseases to malignant tumors with very poor survival. STANDARD RADIOLOGICAL METHODS: Magnetic resonance imaging (MRI) and computed tomography (CT) are the radiological methods of choice for a detailed evaluation of the bile duct system in addition to sonography. By assessing the lumen and the wall of the bile ducts as well as the surrounding structures, both obstructive and nonobstructive pathologies can be diagnosed and differentiated with high sensitivity and specificity. METHODICAL INNOVATIONS: Technical developments with postprocessing modalities as well as the use of biliary-excreted liver-specific MR contrast agents improve the diagnosis of bile duct diseases and enable morphological and functional assessment. PERFORMANCE: Due to high patient tolerance, minimal procedural risk in contrast to invasive endoscopic methods and the possibility of three-dimensional post-processing, beside CT, MRI with magnetic resonance cholangiography (MRC) represents the method of choice in patients with sonographically or clinically suspected bile duct disease and has significantly reduced the indications of diagnostic endoscopic retrograde cholangiopancreatography (ERCP). A complementary multimodality and multiparametric imaging approach is particularly helpful for preoperative assessment. PRACTICAL RECOMMENDATIONS: Rapidly evolving technology for both MRI and CT represent opportunities and challenges. By understanding the advantages and limitations of modern MR and CT techniques and by knowing the spectrum of bile duct pathologies, improved diagnosis and narrowing of possible differential diagnosis can be achieved.

[Role of imaging procedures in clarification of complications of pneumonia]. / Rolle der bildgebenden Verfahren zur Abklärung von Pneumoniekomplikationen.

CLINICAL ISSUE: Despite a considerable number of antimicrobial agents and interdisciplinary treatment options, lower respiratory tract infections are still associated with high morbidity and mortality rates. Infections of the respiratory tract can lead to severe complications, such as empyema, lung abscesses and acute respiratory distress syndrome (ARDS). Besides intrapulmonary complications pneumonia can also impair other organs due to a systemic inflammatory response. Underlying cardiovascular diseases, such as chronic heart failure, arteriosclerosis and dysrhythmia can either deteriorate due to infections or be newly manifested as a result of pneumonia. Early diagnosis and therapy of these sometimes life-threatening complications are crucial and can have a severe impact on disease outcome. STANDARD RADIOLOGICAL METHODS: The most important imaging techniques include chest X­ray and computed tomography (CT) of the chest. Although a definite diagnosis is sometimes difficult or even impossible to establish using chest X­ray or CT, there are several findings indicative of intrapulmonary or extrapulmonary complications of pneumonia. Another useful and portable tool is thoracic ultrasound directly on the patient, which can be used to further define the underlying disease or as guidance during procedures. PRACTICAL RECOMMENDATIONS: The chest X­ray is useful in initial diagnosis and follow-up. If complications or disease progression are suspected or the clinical course differs from the X­ray interpretation, a subsequent CT of the chest should be performed.