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The European Directive 2013/59/Euratom requires member states of the European Union to ensure justification and optimisation of radiological procedures and store information on patient exposure for analysis and quality assurance. The EuroSafe Imaging campaign of the European Society of Radiology created a working group (WG) on "Dose Management" with the aim to provide European recommendations on the implementation of dose management systems (DMS) in clinical practice. The WG follows Action 4: "Promote dose management systems to establish local, national, and European diagnostic reference levels (DRL)" of the EuroSafe Imaging Call for Action 2018. DMS are designed for medical practitioners, radiographers, medical physics experts (MPE) and other health professionals involved in imaging to support their tasks and duties of radiation protection in accordance with local and national requirements. The WG analysed requirements and critical points when installing a DMS and classified the individual functions at different performance levels. KEY POINTS: • DMS are very helpful software tools for monitoring patient exposure, optimisation, compliance with DRLs and quality assurance. • DMS can help to fulfil dosimetric aspects of the European Directive 2013/59/Euratom. • The EuroSafe WG analyses DMS requirements and gives recommendations for users.

Purpose: Evaluation of the benefit of selective venous blood sampling (SVS) for the preoperative identification of parathyroid adenomas with unclear localization in non-invasive diagnostics. Materials and Methods: In a retrospective study, all patients (n = 23) with primary (n = 21) or tertiary (n = 2) hyperparathyroidism were evaluated from 2005 to 2016 at the Hospital Nuremberg-North. These patients all received one (n = 20) or more (n = 3) SVS. 15 patients had one or more previous unsuccessful surgeries (group A), 8 patients received the SVS primarily before the first surgery (group B). Results of SVS were compared with the results of surgery, non-invasive diagnostic procedures and clinical follow up. Results: In 24 out of 26 SVS a significant PTH peak was found. 19 patients underwent surgery after SVS. In 16 of these cases (84 %) the SVS peak was concordant with the intraoperative localization. Thus, SVS of all operated patients had a sensitivity of 94 %. Considering only patients with prior HPT surgery the sensitivity was 89 %. In none of the 26 examinations complications occurred. Conclusion: Our results demonstrate that selective venous blood sampling SVS in cases with unclear imaging of parathyroid adenomas is an effective and low-risk invasive diagnostic method to localize parathyroid adenomas and helps to improve surgical therapy. Key points: • low risk invasive diagnostic procedure to localize parathyroid adenomas• additional step if non-invasive diagnostics are negative or inconclusive• high sensitivity in the detection of parathyroid adenomas Citation Format: • Hader C, Uder M, Loose RWR et al. Selective Venous Blood Sampling for Hyperparathyroidism with unclear Localization of the Parathyroid Gland. Fortschr Röntgenstr 2016; 188: 1144 - 1150., (© Georg Thieme Verlag KG Stuttgart · New York.)

Clinical/methodical Issue: To avoid non-targeted embolization in liver tumors, arteries important for embolization must be detected. In transarterial chemoembolization (TACE) arteries for particle embolization have to be detected and in selective internal radiotherapy (SIRT) extrahepatic arteries which must be protected from embolization have to be detected. In transjugular intrahepatic portosystemic shunt (TIPS) the problem is to achieve an exactly targeted puncture of the portal vein., Standard Radiological Methods: In TACE and SIRT detection of the vessels is performed from various angles by digital subtraction angiography (DSA). In TIPS puncture is guided by ultrasound or performed blindly., Methodical Innovations: Using cone beam CT (CBCT) very small vessels in the liver can be visualized and 2D-3D back projection is able to detect the exact position of the portal vein in TIPS., Achievements: The use of CBCT and 2D-3D back projection significantly enhances navigation of vessels., Practical Recommendations: If flat detector technique is available CBCT should be used in TACE and SIRT and 2D-3D navigation needs hardware and software updates.

Periinterventional Cone-Beam CT (CBCT) today is a valuable tool in complex radiological interventions. Only little experience exists about CBCT in transarterial chemoembolisations (TACE) of liver tumors. 25 patients underwent periinterventional CBCT. We used a C-arc DSA with 30 × 40 cm flat panel detector. Image data with axial, coronal and 3D-reconstruction were acquired by 217° rotation in 8 seconds. In all 25 cases CBCT had an influence on the TACE regarding the decision which vessels to catheterize, the amount of retention of the embolisation agent or an abort because of insufficient vascularisation. In comparison with DSA alone, CBCT allows a better visualisation of tumour vessels, simplifies selective catheterisation, the decision whether an embolisation is possible and enables a good visualisation of Lipiodol retention. Hence, CBCT is a helpful periinterventional tool but cannot substitute CT and MRI in follow up.

During the last years most embolizations with the liquid agent Onyx have been performed in the field of neuroradiological interventions. There is minimal experience with arterial embolizations of the body trunk. 23 patients suffering from acute abdominal or thoracic bleeding underwent 28 embolizations with Onyx (17 male, 6 female, mean age 69 years). 27 interventions were technically and clinically successful. One patient with rebleeding from a jejunal artery aneurysm underwent surgery. Onyx embolizations were performed in renal, hepatic, iliac and bronchial arteries and esophageal varices. Compared with prior embolisation agents Onyx offers advantages due to good controllability. Fast arterial occlusion improves time management of patients. In comparison with prior techniques we observed a significant reduction of fluoroscopy time. Quantitative measurements demonstrated a significant higher embolisation agent contrast., (© Georg Thieme Verlag KG Stuttgart · New York.)

Purpose: The medical X-ray exposure was determined in a 2400-bed hospital. The radiation-related risk was compared with the severity of disease (ICD) to verify the justification for X-ray procedures. A model to estimate radiation and disease-related "loss of lifetime" was applied., Materials and Methods: X-ray exposure from radiography, fluoroscopy and CT was determined for diagnostic and interventional procedures during one hospital stay of 403 patients (0.5 % of all 80 000 patients/year). CTDI and DLP in CT, DAP in fluoroscopy or SED in radiography were used to calculate the effective dose (ED). The disease and radiation-related risk were compared with a simple "loss of lifetime" model., Results: The mean age of all patients was 60. Only a subgroup of 170 patients (42 %) with a mean age of 67.6 had one or more X-ray procedures. The average ED of these exposed patients was 5.12 mSv. 14.4 % CT examinations had a dose contribution of 52.5 % followed by 5.3 % radiology and cardiology procedures at 37.2 %. 90 % of ED was applied to only 44 patients (11 %) and 50 % of ED was applied to only 10 patients (2.5 %) with a mean age of 71.2. 4 of these 10 patients had malignant tumors, the other 6 suffered from pulmonary embolism, pneumonia, stent-graft infection, CAD, Crohn's disease and severe hypertension. The ratio of disease vs. radiation-related risk was between 2.1 : 1 and 1800 : 1., Conclusion: In this study referral for justified X-ray procedures in a large hospital with high level medical care offers a significant patient benefit., ((c) Georg Thieme Verlag KG Stuttgart-New York.)

The purpose of this study was to prevent transjugular intrahepatic portosystemic shunt (TIPS) puncture failure by using three-dimensional (3D) path planning. This study was approved by the institutional review board; informed consent was obtained for the TIPS procedure. In four patients, a 3D path was planned from two two-dimensional (2D) CO2 portograms obtained at projections of 0 degrees and right anterior oblique 30 degrees . This path was overlaid onto the live fluoroscopy to guide the puncture image. In three of four patients, the target vessel was entered in the first attempt. In one patient with portal vein (PV) stenosis, the PV was entered with the third pass. This method has high potential to improve safety of the procedure and to reduce intervention time.

The effect of solvent polarity and lipophilicity on DNA adduct formation by polycyclic aromatic hydrocarbons in skin and lung has been studied in CD1 mice exposed cutaneously in vivo to benzo(a)pyrene ( approximately 0.01-7.0 microg/animal) in either tetrahydrofuran or n-dodecane. The nature and amounts of DNA adducts, measured as 7R,8S, 9R-trihydroxy-10S-(N(2)-deoxyguanosyl-3'-phosphate)-7,8,9, 10-tetrahydrobenzo(a)pyrene, in relation to exposure dose and treatment regime was determined by (32)P-postlabelling. In skin DNA there was a linear relationship between exposure dose and adduct formation with both solvents, though the amount of adduct formed was significantly lower from treatment with benzo(a)pyrene in n-dodecane than in tetrahydrofuran. The amounts of adducts measured in skin DNA ranged from 67 amol adducts/microg DNA at the lowest exposure dose of benzo(a)pyrene in n-dodecane to 3.5 fmol adducts/microg DNA (1 adduct in 5 x 10(7) nucleotides to 1 adduct in 9 x 10(5) nucleotides) at the highest dose. In tetrahydrofuran the corresponding levels were 89 amol adducts/microg DNA (1 adduct in 3 x 10(7) nucleotides) to 16.9 fmol adducts/microg DNA (1 adduct in 2 x 10(5) nucleotides). DNA adducts could not be detected in lung tissue following cutaneous treatment of animals with benzo(a)pyrene in n-dodecane. Cutaneous treatment of animals with benzo(a)pyrene in tetrahydrofuran, however, resulted in adducts in lung DNA at a level of 88 amol/microg DNA from exposures only at the highest dose (6.72 microg/animal). The difference in octanol-water partition coefficient, log P(ow) between n-dodecane compared to tetrahydrofuran is considered to be the most likely reason for the reduction in the bioavailability of benzo(a)pyrene and/or its metabolites and hence the degree of genotoxicity in tissues. The results suggest that other paraffinic hydrocarbon solvents may moderate the genotoxicity of polycyclic aromatic hydrocarbons in vivo. The assessment of the genotoxicity in vivo of mixtures of compounds should be carried out on complete mixtures of substances of interest in order to take account of these possible antagonistic or synergistic effects.

The assessment of skin penetration by viscous oil products is an important element in the risk assessment of these materials where skin contact is likely. Systemic bioavailability (body uptake) is viewed as a good indicator of skin penetration following cutaneous exposures. The results of this study provide quantitative information on the influence of viscosity on the bioavailability of a specific polycyclic aromatic compound (benzo(a)pyrene) in base oils, residual aromatic extracts and bitumens following skin exposures to mice. The materials studied were a base mineral oil (viscosity 32 cSt at 35 degrees C), a 1:1 blend of the mineral base oil and a residual aromatic extract (198 cSt), several residual aromatic extracts (ca. 5000 cSt, 35 degrees C) and a range of bitumens (0.65-69 x 10(6) cSt, 35 degrees C). These were each spiked with 0.1% radiolabelled benzo(a)pyrene, as a representative carcinogenic polycyclic aromatic compound, then used for cutaneous exposures to mice. The results indicate that as viscosity increased in the range ca. 30 to 5000 cSt (base oil to residual aromatic extract) the uptake of the radiolabelled benzo(a)pyrene into blood was reduced by ca. fivefold. Further increases in viscosity from ca. 5000 to 69 x 10(6) cSt (i.e. residual aromatic extract to bitumen) resulted in a further but smaller (ca. twofold) reduction in uptake. The relationship between the amounts of free benzo(a)pyrene measured in blood and viscosity showed the same trend. This trend was also mirrored by the degree of binding of benzo(a)pyrene metabolites to DNA in skin. The findings in mouse skin in vivo indicate that viscosity can significantly affect skin penetration and systemic bioavailability of polycyclic aromatic compound components of oil products. Results obtained with viable human skin in vitro also showed that the bioavailability of benzo(a)pyrene was reduced by the viscosity of the oil product matrix. It is thus necessary to take account of physical properties such as viscosity in the overall risk assessment of viscous oil products, particularly in the case of very viscous materials such as bitumens. The significantly reduced bioavailability of hazardous compounds from undiluted materials is thus an important factor to consider when assessing the risks from dermal exposures.

The in vivo genotoxic activities in mouse skin of the dimethyl sulphoxide (DMSO) extracts of a range of oil products [residual aromatic extract; untreated heavy paraffinic distillate aromatic extract; mildly refined light naphthenic base oil; bitumen (vacuum residue); high viscosity index base oil obtained by catalytic hydrogenation] were evaluated by 32P-postlabelling DNA analysis. The results of quantitative 32P-postlabelling analyses of epidermal DNA from mice treated with the DMSO extracts showed linear relationships with the total polycyclic aromatic compound (PAC) contents, determined by the Institute of Petroleum method IP 346 and also the 3-6 ring PAC contents, measured by on-line liquid-liquid extraction using flow injection analysis. The 32P-postlabelling data also showed a linear relationship with the mutagenicity indices of these oil products determined in S. typhimurium TA98 using the modified Ames Salmonella microsome test. The in vivo genotoxicity of the DMSO extracts from the oil products was low, judged by 32P-postlabelling analysis of DNA adducts measured in epidermal DNA of treated mouse skin, and ranging from 2 to 723 attomole/microg DNA per mg oil product. The in vivo 32P-postlabelling data from this study are consistent with these materials expressing low genotoxicity in mouse skin in vivo. The DMSO extraction procedure coupled with 32P-postlabelling DNA analysis is useful for ranking the relative genotoxic potency in vivo of a wide range of oil products. In general the trend observed is similar to rankings based on physicochemical measurements of total PAC contents or 3 6 ring PAC contents of the oil products.

A systematic molecular phenotyping approach based on two-dimensional gel electrophoresis is being applied in an attempt to identify protein changes associated with malignant transformation. Using the C3H10T1/2 mouse cell line, two-dimensional polypeptide maps of the non-transformed cell line, several chemically transformed lines and a tumour cell line were compared. Although there is a large degree of similarity between the protein profiles of all cell lines, clear differences are evident. Initial results are consistent with the view that many of the protein changes are incidental to malignant transformation. Changes induced by 3-methylcholanthrene are retained after transplantation of the cells into nude mice.