[Idiopathic pulmonary fibrosis : Radiological diagnosis in light of the current guidelines]. / Idiopathische pulmonale Fibrose : Radiologische Diagnose unter Berücksichtigung der aktuellen Leitlinie.

Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic progressive fibrosing interstitial lung disease with a poor prognosis. High-resolution computed tomography (HRCT) plays an important role in the work-up of patients with suspected IPF. In HRCT IPF is characterized by the pattern of usual interstitial pneumonia (UIP). For a long time only supportive or immunosuppressive treatment was possible. The approval of antifibrotic agents in 2012 marked a turning point and triggered further clinical and scientific interest. Based on the recently gained knowledge the revised version of the international guidelines for the diagnosis of IPF was published in 2018, including instructions for HRCT interpretation. In this continued medical education article the relevant signs in HRCT are presented. The specifications given in the guidelines are elucidated.

[Early recognition of lung cancer in workers occupationally exposed to asbestos]. / Früherkennung von Lungenkrebs bei asbestexponierten Arbeitnehmern.

Despite the fact that working with asbestos and placing it on the market have been banned in Germany since 1993 according to the Ordinance on Hazardous Substances, asbestos-related diseases of the lungs and pleura are still the leading cause of death in occupational diseases. The maximum industrial usage of asbestos was reached in former West Germany in the late 1970s and in former East Germany the late 1980s. Occupational diseases, mainly mesotheliomas and lung cancer emerging now are thus caused by asbestos exposure which occurred 30-40 years earlier. It is known that the combination of smoking and asbestos exposure results in a superadditive increase in the risk to develop lung cancer. No suitable screening methods for early detection of malignant mesothelioma are currently available and the therapeutic options are still very limited; however, the national lung screening trial (NLST) has shown for the first time that by employing low-dose computed tomography (LDCT) in heavy smokers, lung cancer mortality can be significantly reduced. According to current knowledge the resulting survival benefits far outweigh the potential risks involved in the diagnostic work-up of suspicious lesions. These results in association with the recommendations of international medical societies and organizations were pivotal as the German statutory accident insurance (DGUV) decided to provide LDCT as a special occupational medical examination for workers previously exposed to asbestos and with a particularly high risk for developing lung cancer.

[Pulmonary manifestations of connective tissue diseases]. / Pulmonale Beteiligung bei Kollagenosen.

Systemic autoimmune diseases are responsible for about 25% of all deaths due to interstitial lung disease; therefore, an early identification of patients with pulmonary manifestation changes the management. Detection, differential diagnostic classification and staging of the pneumological pattern of findings are largely based on high-resolution computed tomography (HR-CT). The main differential diagnostic challenges are interstitial manifestations which present with radiological-histopathological phenotypes of interstitial pneumonia. The most common form of interstitial pulmonary reaction form of connective tissue diseases is the nonspecific interstitial pneumonia (NSIP) pattern. In rheumatoid arthritis, a usual interstitial pneumonia (UIP) pattern is dominant. Uncharacteristic reactions of airways and pleura can be the leading symptom or present as accompanying findings. A serious complication is pulmonary hypertension. Drug-induced lung lesions can present with similar HR-CT morphology as connective tissue diseases and can only be differentiated in the temporal and clinical context.

[Management of solid pulmonary nodules]. / Management solider pulmonaler Rundherde.

The increasing availability of computed tomography has meant that the number of incidentally detected solitary pulmonary nodules (SPN) has greatly increased in recent years. A reasonable management of these SPN is necessary in order to firstly be able to detect malignant lesions early on and secondly to avoid upsetting the patient unnecessarily or carrying out further stressful diagnostic procedures. This review article shows how the dignity of SPNs can be estimated and based on this how the management can be accomplished taking established guidelines into consideration.

[Pitfalls in diagnostic imaging and assessment of benign asbestos-related thoracic diseases]. / Fallstricke in der radiologischen Diagnostik und Begutachtung der benignen asbestbedingten Erkrankungen des Thorax.

The recognition of asbestos-related diseases of the lung and/or pleura as an occupational disease is of psychosocial, medical and legal importance to the insured person. Radiological imaging is an essential part of the assessment and requires an increasingly high level of competence in the field of radiological diagnosis of pneumoconiosis in interdisciplinary collaboration with occupational medicine and pneumonology. The chest radiogram remains an integral part of basic diagnostic procedures in asbestos-related diseases of the lungs and/or pleura. Its importance lies in the detection of extended pleural changes as well as substantial fibrosis. The inherent low sensitivity and specificity of projection radiography is taken into account by the increasing use of multi-slice high resolution (HR) CT (in low dose technique). Radiological pitfalls in pleural plaque assessment with respect to plain chest X-ray concern all structures that superimpose on the pleural circumference, particularly the anatomical layers of the chest wall (extra-pleural fatty tissue, muscles, thoracic skeleton) as well as other pulmonary findings that can only be reliably assigned using CT. Even if state-of the-art CT is applied, asymmetries and abnormal expression of anatomical structures and variants (e. g. muscles and blood vessels) can lead to false-positive findings. The interstitial fibrosis of asbestosis, manifested as usual interstitial pneumonia (UIP) is non-pathognomonic for asbestosis. Therefore, parietal pleural thickening as a coincident finding to UIP is considered as being the main feature and a highly suggestive indicator of asbestosis in patients with a history of asbestos exposure.

[Diagnostic imaging of pulmonary lymphangiosis carcinomatosis]. / Bildgebende Diagnostik der pulmonalen Lymphangiosis carcinomatosa.

The diagnosis of pulmonary lymphangiosis carcinomatosa (PLC) is of great importance for the prognostically-oriented therapy stratification of tumor patients. In this field, high-resolution computed tomography (HRCT) is the state of the art in imaging. Using HRCT, it is possible to identify pulmonary parenchymal structures in a detailed fashion to evaluate interstitial patterns. This step is preceded by an x-ray of the thorax that detects pathological findings and rules out other diseases. The typical characteristics of PLC are described with particular attention to HR-phenomenology, and discussed in comparison with the literature regarding anatomy and pathogenesis. Finally, conclusions are drawn for differential diagnosis and supported by characteristic cases.

[Chest examination protocol with a reduced dose using a multi-slice spiral CT]. / Thorax-Untersuchungsprotokoll mit reduzierter Dosis an einem Mehrschicht-Spiral-CT.

PURPOSE: Comparison of multi-slice computed tomography (MSCT) for examination of the chest using two protocols differing in tube voltage (kV) and effective tube current (mAs), as to image quality, diagnostic quality and radiation dose. MATERIAL AND METHODS: Re-staging examinations of 20 patients with bronchial carcinoma on a MSCT (Somatom Volume Zoom, Siemens AG, Forchheim) with 140 kV/100 mAseff and again after an average interval of 4.5 months, a second examination using 120 kV/80 mAseff, employing identical detector width (4 x 2.5 mm), slice, pitch, increment, kernel and selecting the same use or non-use of contrast medium. Image quality, delineation of mediastinal and pulmonary anatomy and pathology, and frequency of artifacts were evaluated by two radiologists and the effective radiation doses were calculated. RESULTS: Subjective image quality was good to very good for both protocols, and no significant differences were found for visualizing anatomic and pathologic structures in mediastinum and lung. Only the region surrounded by the shoulder girdle showed significantly more artifacts with 120 kV/80 mAsff, but without loss of diagnostic quality. The effective doses were 8 mSv (women) and 6 mSv (men) for 140 kV/100 mAseff versus 4.3 mSv and 3.3 mSv for 120 kV/80 mAseff. CONCLUSIONS: In view of the equal diagnostic quality of both images, CT of the chest should be obtained with 120 kV and 80 mAseff rather than with 140 kV/100 mAseff, regardless of the slightly lower aesthetic quality of the former. This will keep the radiation dose as low as possible. Follow-up examinations should be obtained with even further dose reduction (low dose CT).

Analysis of oxylipins by high-performance liquid chromatography with evaporative light-scattering detection and particle beam-mass spectrometry.

The metabolism of 13S-hydroperoxy-9Z,11E,15Z-octadecatrienoic acid was investigated in a crude enzyme extract from mung bean seedlings (Phaseolus radiatus L.). Hydroperoxide-metabolizing activity was mainly due to a hydroperoxide lyase and, to a lesser extent, to an allene oxide synthase and a peroxygenase. Oxylipins originating from hydrolysis and cyclization of the allene oxide synthase product 12,13-epoxy-9Z,11,15Z-octadecatrienoic acid and from peroxygenase catalysis were identified by high-performance liquid chromatography (HPLC) particle beam-mass spectrometry (PB-MS) and quantified by normal-phase HPLC with an evaporative light-scattering detector (ELSD). An advantage of this methodology was the possibility to avoid extensive derivatization procedures commonly used for the gas chromatographic analysis of oxylipins. Owing to a comparable sample inlet system, the ELSD served an important analytical pilot function for the PB-MS: Qualitatively identical chromatographic patterns were obtained with both detection systems. The HPLC system enabled the separation of methyl 12-oxo-phytodienoate, methyl 11-hydroxy-12-oxo-9Z,15Z-octadecadienoate, methyl 12-oxo-13-hydroxy-9Z,15Z-octadecadienoate, methyl 9-hydroxy-12-oxo-10E,15Z-octadecadienoate, methyl 13-hydroxy-9Z,11E,15Z-octadecatrienoate, methyl 15,16-epoxy-13-hydroxy-9Z,11E-octadecadienoate, and methyl 13-hydroperoxy-9Z,11E,15Z-octadecatrienoate on a Lichrospher DIOL column within 33 min. Compared with a diode array detector, the ELSD proved to be more sensitive, in the case of methyl 12-oxo-13-hydroxy-9Z, 15Z-octadecadienoate by a factor of about 15. In addition, volatile metabolites were analyzed by capillary gas chromatography. The yield of the hydroperoxide lyase product 2E-hexenal was 49%, whereas the sum of oxylipins reached about 15%.