Search

Die vom Ausschuss für Gefahrstoffe (AGS) überarbeitete und 2019 veröffentlichte Technische Regel für Gefahrstoffe (TRGS) 554 „Abgase von Dieselmotoren“ weist eine Reihe von Änderungen gegenüber der bisherigen Fassung auf. So wurden insbesondere wegen der Festlegung neuer Arbeitsplatzgrenzwerte neben den partikulären Dieselrußpartikeln auch die Stickoxide – Stickstoffmonoxid und -dioxid – berücksichtigt. Die in der Motorentechnik und der Abgasnachbehandlung erfolgten technischen Weiterentwicklungen fanden ebenfalls ihren Niederschlag. In dieser Veröffentlichung werden einige erläuternde Hinweise zur praktischen Anwendung dieser TRGS geliefert.

Der Gesprächskreis BITUMEN führt seit vielen Jahren Arbeitsplatzmessungen bei Tätigkeiten mit heißem Bitumen durch. Anfangs wurden nur in Deutschland die Konzentrationen der Dämpfe und Aerosole aus Bitumen bei der Produktion von Bitumenbahnen sowie beim Schweißen von Bitumenbahnen ermittelt. Seit 2010/2011 werden auch in anderen europäischen Staaten solche Messungen vorgenommen. Über den aktuellen Stand der Kenntnisse der Expositionen bei diesen Arbeiten unter Berücksichtigung des neuen Vorschlags der MAK-Kommission für einen Grenzwert wird berichtet. Dabei wird auch die Exposition bei der Produktion von Bitumendämpfungsfolien erläutert.

Bid–ask spreads using intraday data reveal significant sensitivity to European Central Bank (ECB) macro-announcements. Effects are strongest for announcements that comprise unexpected information or a change in interest rates, and spreads rise sharply during the minutes surrounding interest rate or other important macroeconomic announcements by the ECB. Both Euro area stocks (of German DAX 30 and French CAC 40) and non-Euro area stocks (of FTSE 100) have been used for comparative reasons. All results are robust to changes in specification and when being controlled for normal daytime-dependent frictions and stock-specific characteristics.

This paper analyses the interest rate-setting behaviour of the ECB and the former leading monetary authority in the Eurozone, the German Bundesbank, using Taylor rules in different GMM-estimation setups. The main findings are as follows: the Bundesbank was clearly stability oriented with regard to inflation and included output stabilization, interest rate smoothing and inflation forecasts in its decision-making process during the period under investigation, that is 1979M01-1998M12. Furthermore, evidence of the inclusion of the quantity of money in the decisions has been found at least for the 1980s. The estimation results for the ECB from 1999M01 onwards reveal a monetary policy that is less stability oriented than that of the Bundesbank in that it clearly violates the Taylor principle. According to this, the ECB cannot be seen as the successor of the Bundesbank as regards the way it has conducted monetary policy.

To determine local tumor control after CT-guided brachytherapy at various dose levels and the prognostic impact of extensive cytoreduction in colorectal liver metastases.Seventy-three patients were treated on a single-center prospective trial that was initially designed to be randomized to three dose levels of 15 Gy, 20 Gy, or 25 Gy per lesion, delivered in a single fraction. However, because there was a high rate of cross-over of subjects from higher to lower dose levels, this study is better understood as a prospective trial with three dose levels. No upper size limit for the metastases was applied. We assessed time to local progression, progression-free survival, and overall survival.According to safety constraints cross-over was performed. The final assignment was n = 98, n = 68, and n = 33 in the 15-Gy, 20-Gy, and 25-Gy groups, respectively. Median diameter of the largest tumor lesion in each patient was 5 cm (range, 1-13.5 cm). Estimated mean local recurrence-free survival for all lesions was 34 months (median not reached). The group assigned to 15 Gy after cross-over displayed 34 local recurrences out of 98 lesions; 20 Gy, 15 out of 68 lesions; 25 Gy, 1 out of 33 lesions. The difference between the 25-Gy and the 20-Gy or 15-Gy group was significant (p0.05). Repeated local tumor ablations were the most prominent factor for increased survival and dominated additional systemic antitumor treatments.Local tumor control after CT-guided brachytherapy of colorectal liver metastases demonstrated a strong dose dependency. The role of extensive minimally invasive tumor ablation in metastatic colorectal cancer needs to be further established.

Retinol (ROL) and β-carotene (BC) are vitamin A (VA) derivatives and are taken up by humans for use as nutrients. The intake of these derivatives can be calculated by extrapolation from food consumption data. In this study, food consumption statistics of the former West and East German regions between 1986 and 1993 were calculated, concentrating on East Germany’s transition towards reunification with West Germany. Retinol equivalent (RE), ROL and BC intakes in 1986 were much lower in East Germany than in West Germany. A strong increase in the uptake levels of RE, ROL and especially BC from 1986 to 1993 was observed in East German women, men and children, and was partly dependent on household financial status. This remarkable elevation was most likely caused by alterations in consumed food varieties in East Germany following reunification. Since high dietary intake of VA was shown to be associated with atopy, the observed elevated RE, ROL and especially BC uptake of East Germans might also have affected th...

Purpose To determine the additional value of fluorodeoxyglucose-positron emission tomography (PET) for clinical target volume definition in the planning of computed tomography (CT)-guided interstitial brachytherapy for liver metastases. Patients and Methods A total of 19 patients with liver metastases from colorectal cancer treated in 25 sessions were included in the present study. All patients had undergone fluorodeoxyglucose-PET for patient evaluation before interstitial CT-guided brachytherapy. A contrast-enhanced CT scan of the upper abdomen was obtained for radiation planning. The clinical target volume (CTV) was defined by a radiation oncologist and radiologist. After registration of the CT scan with the PET data set, the target volume was defined again using the fusion images. Results PET revealed one additional liver lesion that was not visible on CT. The median CT-CTV (defined using CT and magnetic resonance imaging) was 68 cm 3 (range 4–260). The PET/CT-CTV (median, 78 cm 3 ; range, 4–273) was significantly larger, with a median gain of 24.5% (interquartile range, 2.1–71.5%; p = .022). An increased CTV was observed in 15 cases and a decrease in 6; in 4 cases, the CT-CTV and PET/CT-CTV were equal. Incomplete dose coverage of PET/CT-CTVs was indicative of early local progression ( p = .004); however, CT-based radiation plans did not show significant differences in the local control rates when stratified by dose coverage. Conclusion Retrospective implementation of fluorodeoxyglucose-PET for CTV specification for CT-guided brachytherapy for colorectal liver metastases revealed a significant change in the CTVs. Additional PET-positive tumor regions with incomplete dose coverage could explain unexpected early local progression.

New interventional options especially for patients with HCC and BCLC scores B and C give rise to disputes about the optimal therapeutic management. CT-guided brachytherapy complements established interventional techniques like RFA and TACE since it may also be used successfully in tumors much greater than 5 cm in diameter. In addition, unlike thermal ablation, the brachytherapy technique may be applied in tumors located nearby risk structures such as liver hilum or gallbladder and it is independent of cooling effects such as through large blood vessels or strong tumor perfusion. Depending on tumor size, geometry and visibility, MRI or CT guidance may be used. 15 Gy minimal target dose can be applied safely in a single or – in case of very large tumors – a sequential approach targeting different tumor portions. Local recurrence rates will be very low, and the rate of complications is moderate despite the fact that most patients present with underlying cirrhosis and related comorbidities. Preliminary data suggest a positive impact on overall survival. Randomized controlled trials are on their way to assess combination schemes with systemic treatments such as sorafenib.

To compare local tumor control after percutaneous tumor ablation by interstitial laser therapy (ILT) or CT-guided brachytherapy (CTGB). In a matched pair analysis including 18 patients with 36 liver metastases of colorectal primary, both ILT and CTGB were performed in different lesions. The following matching factors were considered: (i) tumor size ≤ 5 cm, and (ii) execution of chemotherapy after tumor ablation. Primary endpoint was local tumor control. Treated lesions were identical in terms of tumor size and all matching criteria were fulfilled in all patients except for the performance of adjuvant chemotherapy. Median follow-up was 14 months (3–24 months) for both groups. Only five of 18 patients (28%) demonstrated local tumor progression after CTGB, whereas in ten of 18 patients (56%) tumor progression was found after ILT. Differences encountered were significant for all patients (p = 0.04), whereas in those who fulfilled all matching criteria (n = 14) the level of statistical significance was not reached (p = 0.23). CTGB demonstrated superior local tumor control compared to ILT in long-term follow-up.

To assess both sensitivity and specificity of digital chest radiography alone and in conjunction with dual-exposure dual-energy chest radiography for the detection and classification of pulmonary nodules. One hundred patients with a total of 149 lung nodules (3-45 mm; median, 11 mm) confirmed by CT were included in this study. Dual-exposure dual-energy chest radiographies of each patient were obtained using a CsI detector system. Experienced board-certified chest radiologists from four different medical centers in Europe reviewed standard chest radiographs alone and in conjunction with dual-energy images blinded and in random order. The reviewers rated the probability of presence, calcification and malignancy of all lung nodules on a five-point rating scale. Lesions detected were identified by applying a specific coordinate system to enable precise verification by the study leader. A receiver-operating characteristic (ROC) analysis was performed. In addition to the 149 true-positive CT proven lesions, 236 false-positive lung nodules were described in digital chest radiographies in conjunction with dual-energy chest radiographies. The cumulative sensitivity of chest radiography in conjunction with dual energy was 43%, specificity was 55%. For digital radiography alone, sensitivity was 35% and specifity was 83%. For the dual energy system, positive predictive value was 58%, and negative predictive value was 66% compared to the digital radiography with a positive predictive value of 59% and a negative predictive value of 65%. Areas under the curve in a ROC analysis resulted in 0.631 (95% confidence interval =0.61 to 0.65) for radiography with dual energy and 0.602 (95% confidence interval =0.58 to 0.63) for digital radiography alone. This difference was not statistically significant. For the detection of lesion calcification or the determination of malignancy, ROC analysis also failed to show significant differences. CsI-based flat-panel dual-exposure dual-energy imaging added to standard chest radiography did not show statistically significant improvement for the detection of pulmonary nodules, nor the identification of calcifications, nor the determination of malignancy.

The purpose of the study was to establish a diagnostic approach to the preparation of patients with colorectal liver metastases considered for transarterial radioembolization (RE). Twenty-two patients sequentially underwent computed tomography (CT; thorax/abdomen), magnetic resonance imaging (MRI; liver; hepatocyte-specific contrast), positron emission tomography (PET/PET-CT; F18-fluoro-desoxy-glucose), and angiography with perfusion scintigraphy [planar imaging; tomography with integrated CT (SPECT-CT)]. The algorithm was continued when no contraindication or alternative treatment option was found. The impact of each test on the therapy decision and RE management was recorded. Patient evaluation using CT revealed contraindications for RE in 4/22 patients (18%). Of the remaining 18 patients, 2 were excluded and 3 were assigned to locally ablative treatment based on MRI and PET results (28%). The remaining 13 patients entered the planning algorithm: SPECT-CT revealed gastrointestinal tracer accumulations in 4 (31%) patients [SPECT, 2 (15%)], making a modified application necessary. In five patients (38%), planar scintigraphy revealed relevant hepatopulmonary shunting. Therapy was finally administered to all 13 patients without therapy-related pulmonary or gastrointestinal morbidity. Each part of the diagnostic algorithm showed a relevant impact on patient management. The sequential approach appears to be suitable and keeps the number of unnecessary treatments and therapy risks to a minimum.

In this study, we analyze the effects of US macroeconomic announcements on European stock returns, return volatility and bid-ask spreads using intraday data. While an index-based analysis provides expected outcomes of differing importance of macro-economic announcements, we provide first evidence on stock-specific reactions. The study further contributes by disentangling stock-specific impacts from overall market reactions. A spread analysis reveals that return volatility affects the spread size positively, and that spreads are systematically higher directly after news releases. This is followed by structurally lower spreads, indicating quickly decreasing asymmetric information in the market after announcements. Additionally, spreads tend to react to announcements even if the returns or the volatility of the underlying stock is not significantly affected. This points at the importance of the analysis of news events beyond return and volatility analyses.

In this study, we analyze the effect of US macroeconomic announcements on European stock returns, return volatility and bid-ask spreads using intraday data. We find that certain announcements are generally more important to the European stock market than others, and that the direction of news is important for returns. We provide first evidence that a stock-individual analysis is crucial to disentangle overall market reactions from stock-specific impacts and that effects vary dramatically between stocks. The analysis of quoted spreads reveals that return volatility affects the spread size positively, and that spreads are systematic ally higher directly after news releases. This is followed by structurally lower spreads, indicating quickly decreasing asymmetric information in the market after announcements. Additionally, spreads tend to react to announcements even if the returns or the volatility of the underlying stock is not significantly affected. This points at the importance of the analysis of news events beyond return and volatility analyses.

In this study, we analyze the effect of US macroeconomic announcements on European stock returns, return volatility and bid-ask spreads using intraday data. We find that certain announcements are generally more important to the European stock market than others, and that the direction of news is important for returns. We provide first evidence that a stock-individual analysis is crucial to disentangle overall market reactions from stock-specific impacts and that effects vary dramatically between stocks. The analysis of quoted spreads reveals that return volatility affects the spread size positively, and that spreads are systematically higher directly after news releases. This is followed by structurally lower spreads, indicating quickly decreasing asymmetric information in the market after announcements. Additionally, spreads tend to react to announcements even if the returns or the volatility of the underlying stock is not significantly affected. This points at the importance of the analysis of news events beyond return and volatility analyses.

Einleitung Zu den Fruhstadien der altersbedingten Makuladegeneration zahlen miliare und serose Drusen und Pigmentepithel Veranderungen. Die optische Koharenztomographie (OCT) stellt ein bildgebendes Verfahren mit hoher Auflosung der retinalen Strukturen der Makula dar. Ziel der Studie ist es, OCT- und fluoreszenzangiographische Befunde bei Patienten mit Drusenmakulopathie bezuglich der prognostischen Aussagekraft zu vergleichen.

We have developed a compilation system which extends High Performance Fortran (HPF) in various aspects. We support the parallelization of well-structured problems with loop distribution and alignment directives similar to HPF's data distribution directives. Such directives give both additional control to the user and simplify the compilation process. For the support of unstructured problems, we provide directives for dynamic data distribution through user-defined mappings. The compiler also allows integration of message-passing interface (MPI) primitives. The system is part of a complete programming environment which also comprises a parallel debugger and a performance monitor and analyzer. After an overview of the compiler, we describe the language extensions and related compilation mechanisms in detail. Performance measurements demonstrate the compiler's applicability to a variety of application classes.

Bid-ask spreads using intraday data reveal significant sensitivity to European Central Bank (ECB) macro announcements. Effects are strongest for announcements that comprise unexpected information or a change in interest rates, and spreads rise sharply during the minutes surrounding interest rate or other important macroeconomic announcements by the ECB. Both Euro area stocks (of German DAX 30 and French CAC 40) and non-Euro stocks (of FTSE 100) have been used for comparative reasons. All results are robust to changes in specification and when being controlled for normal daytime-dependent frictions or other macroeconomic announcements.

While productive use of parallel systems for business applications is quickly growing, their usage for scientific applications is far below expectations. The main reason is that programming of parallel systems is still far too complex. Starting from an analysis of the user requirements, this paper explains our strategy towards next-generation parallel programming environments. We first discuss the problem areas of parallel programming from a user's point of view and give an overview on existing low-, high- and intermediate-level tools. We summarize our objectives and the status of our research. Then we discuss three enabling technologies to overcome current-days limitations of tool environments for parallel computing: formal specification languages, artificial intelligence, and compiler technology. The impact of these technologies on the components proposed for a next-generation programming environment is discussed in detail.

Background To assess radiobiological restrictions and tolerance doses as well as other toxic effects derived from repeated applications of single-fraction high dose rate irradiation of small liver volumes in clinical practice. Methods Twenty patients with liver metastases were treated repeatedly (2 - 4 times) at identical or intersecting locations by CT-guided interstitial brachytherapy with varying time intervals. Magnetic resonance imaging using the hepatocyte selective contrast media Gd-BOPTA was performed before and after treatment to determine the volume of hepatocyte function loss (called pseudolesion), and the last acquired MRI data set was merged with the dose distributions of all administered brachytherapies. We calculated the BED (biologically equivalent dose for a single dose d = 2 Gy) for different α/β values (2, 3, 10, 20, 100) based on the linear-quadratic model and estimated the tolerance dose for liver parenchyma D90 as the BED exposing 90% of the pseudolesion in MRI. Results The tolerance doses D90 after repeated brachytherapy sessions were found between 22 - 24 Gy and proved only slightly dependent on α/β in the clinically relevant range of α/β = 2 - 10 Gy. Variance analysis showed a significant dependency of D90 with respect to the intervals between the first irradiation and the MRI control (p < 0.05), and to the number of interventions. In addition, we observed a significant inverse correlation (p = 0.037) between D90 and the pseudolesion's volume. No symptoms of liver dysfunction or other toxic effects such as abscess formation occurred during the follow-up time, neither acute nor on the long-term. Conclusions Inactivation of liver parenchyma occurs at a BED of approx. 22 - 24 Gy corresponding to a single dose of ~10 Gy (α/β ~ 5 Gy). This tolerance dose is consistent with the large potential to treat oligotopic and/or recurrent liver metastases by CT-guided HDR brachytherapy without radiation-induced liver disease (RILD). Repeated small volume irradiation may be applied safely within the limits of this study.

Backround Micrometastases of colorectal liver metastases are present in up to 50% of lesions. In this study we sought to determine the threshold dose for local control of occult micrometastases in patients undergoing CT (computed tomography)-guided brachytherapy of colorectal liver metastases. Materials and methods Nineteen patients demonstrated 34 local tumor recurrences originating from micrometastases after CT-guided brachytherapy of 27 colorectal liver metastases. We considered a local tumor recurrence as originating from a micrometastasis if tumor regrowth occurred adjacent to a formerly irradiated lesion and the distance of the 3D isocenter of the new lesion was ≤ 23.5 mm from the previous tumor margin. Follow-up MRI was fused with the planning-CT and dosimetry data. Two reviewers independently indicated the dose exposure at the isocenter of the micrometastases. Statistical analysis included an analysis of variance (ANOVA) using backward selection. 95% tolerance intervals with coverage of 87.5 and 75% of the data of the normal distribution were calculated. Results The median distance of the micrometastases to the margin of the originating colorectal metastases was 8.75 mm (1-21 mm). Dose exposure at the isocenter was 12.25 Gy (7-19.8) in median. We stratified according to the distance from the isocenter to the initial tumor margin: ≤ 9 mm, > 9-15 mm and > 15 mm. The median dose in the according isocenters was 13.18, 11.6 and 11.85 Gy. The threshold dose failing to prevent micrometastasis growth was sigificantly higher in a subgroup of lesions with ≤ 9 mm distance as compared to > 15 mm (13.18 vs 11.85 Gy). Adjuvant chemotherapy correlated with greater distance of micrometastasis growth to the tumor but not with the threshold dose. Conclusion To prevent loss of local tumor control by continuous growth of micrometastases a threshold dose of 15,4 Gy (single fraction) should be delivered at a distance of 21 mm to the gross tumor margin.

Background and Aim: Sorafenib has become the treatment standard for patients with advanced hepatocellular carcinoma (HCC). It is not clear whether patients with advanced liver function impairment (Child B) and patients undergoing additional locoregional therapy may tolerate treatment with sorafenib and benefit. We aimed to evaluate the tolerability and efficiency of sorafenib in patients with advanced HCC and different stages of liver cirrhosis, and in combination with locoregional therapy. Methods: In 50 patients with advanced HCC treated with sorafenib tolerability and efficiency of the therapy with respect to stage of liver cirrhosis, existence of extrahepatic tumor spread, and additional locoregional therapy were evaluated. Results: Fifty patients with advanced HCC were treated with sorafenib, and 13 received additional locoregional therapy. Tolerability of the systemic treatment was moderate in all patients, with no significant differences between the subgroups, while the median survival was better in patients with Child A than Child B cirrhosis. Conclusion: Tolerability and toxicity of a systemic treatment with sorafenib are moderate in patients with liver cirrhosis in Child A or B. Prospective randomized studies are required to evaluate the efficacy and tolerability of combined systemic and locoregional treatment approaches in patients with advanced HCC.

To prospectively evaluate diffusion-weighted imaging (DWI) for early prediction of tumour response in patients with colorectal liver metastases following selective internal radiotherapy (SIRT).We evaluated 41 metastases in 21 patients, age 62.9 ± 9.9 years. All patients underwent magnetic resonance imaging (MRI) including breath-hold echoplanar DWI sequences. Imaging was performed before therapy (baseline MRI), 2 days after SIRT (early MRI) as well as 6 weeks later (follow-up MRI). Tumour volume (TV) and intratumoural apparent diffusion coefficient (ADC) were measured independently by two radiologists at all time points.Metastases were categorised as responding lesions (RL; n = 33) or non-responding lesions (NRL; n = 8) according to changes in TV after 6 weeks. We found an inverse correlation of changes in TV and ADC at follow-up MRI with a Pearson's correlation coefficient of r = -0.66 (p 0.0001). On early MRI, no significant changes in TV were found for either RL or NRL. Conversely, ADC decreased significantly in RL by 10.7 ± 8.4% (p 0.0001). ADC increased in NRL by 9.6 ± 20.8%, which was not statistically significant (p = 0.40).DWI was capable of predicting therapy effects of SIRT in patients with colorectal hepatic metastases as early as 2 days following treatment.

This prospective study was designed to assess the diagnostic value of magnetic resonance angiography (MRA) with blood-pool contrast agent (gadofosveset) in the detection of type-II endoleak after endovascular aortic repair (EVAR).Thirty-two patients with aortic aneurysms who had undergone EVAR were included in this study. All patients were examined by dual-phase computed tomography angiography (CTA) as well as MRA with gadofosveset in the first-pass and steady-state phases. Two independent readers evaluated the images of CTA and MRA in terms of endoleak type II, feeding vessel, and image quality.Median follow-up-time after EVAR was 22 months (range 4 to 59). Endoleak type II was detected by CTA in 12 of 32 patients (37.5%); MRA detected endoleak in all of these patients as well as in another 9 patients (n = 21, 65.6%), of whom the endoleaks in 6 patients showed an increasing diameter. Most endoleaks were detected in the steady-state phase (n = 14). The decrease in diameter of the aneurysmal sac was significantly greater in the patients without a visible endoleak that was visible on MRA (P = 0.004). In the overall estimation of diagnostic accuracy, MRA was judged superior to CTA in 66% of all examinations.MRA with gadofosveset appeared superior to CTA, and has higher diagnostic accuracy, in the detection of endoleak after EVAR.

10 M comparable to 10 M WY14,643. Therefore, PPARα-mediated mechanism is a possible relevant pathway for FE anti-diabetic activity. We also evaluated the effects of a low-fat diet (LFD), high-fat diet (HFD), and high fat diet + 0.5% FE (FED) on C57BL/6J mice during 16-weeks. FED decreased fasting blood glucose (33.2%, P

Purpose: To identify changes of liver function after single-fraction irradiation or yttrium-90 radioembolization (90Y-RE) of hepatocellular carcinoma associated with liver cirrhosis on the basis of laboratory data. Methods and Materials: 24 patients with primary liver carcinoma and liver cirrhosis classified Child-Pugh A or B were treated either by image-guided high-dose-rate brachytherapy (HDR-BT) (12 patients) or by 90Y-RE (12 patients). The following laboratory parameters were assessed 1 day before and 3 days, 6 weeks and 3 months after the intervention: total bilirubin and γ-glutamyl transpeptidase (GGTP) as parameters of detoxification function, albumin and cholinesterase (ChE) as direct synthesis parameters, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (AP) as indicators of liver tissue damage. Preinterventional values were taken as baseline, following values were calculated as percentage changes from the baseline value. Statistical analysis was performed using the Wilcoxon-matched pairs test, comparing postinterventional with preinterventional values. Differences were considered statistically significant with a p value Results: In all patients the median bilirubin, ALT, AP and albumin values remained within normal limits at any time of follow-up. AST levels in the RE group and GGTP in both groups have been already elevated over a normal range before the intervention, and in both groups both parameters showed a slight increase after interventions. ChE activity was lowered already in the baseline values and showed a further decrease 3 days after BT as well as 3 days and 6 weeks after RE, with final reconstitution to baseline values. All liver function test parameters showed mild changes shortly after radiation therapy but floating laboratory values recovering within 12 weeks to baseline values. Radiation or RE-induced liver disease was recorded in no patient. Conclusions: Liver function parameters show only mild changes shortly after intervention with recovery within 6–12 weeks to baseline values.

To prospectively assess a dose-response relationship for the hepatic reticulo-endothelial system (RES) after small volume single fraction irradiation of liver parenchyma in vivo.Twenty-five liver tumors were treated by computed tomography (CT)-guided interstitial brachytherapy. Magnetic resonance imaging (MRI) was performed 1 day before and 3 days, 6, 12 and 24 weeks after therapy. MR-sequences included T2-w Turbo Spin Echo (TSE) enhanced by hepatic RES targeted Standard Superparamagnetic Iron Oxide (SSPIO). All MRI data sets were merged with three dimensional (3D) dosimetry data and evaluated by two radiologists. We estimated the threshold dose for either edema or function loss as the D90. A match-pair analysis was performed with another 25 liver tumors, which were treated the same but had MRI follow-up using the hepatocyte specific MRI contrast media Gadobenate dimeglumine (Gd-BOPTA).Three days post brachytherapy the D90 for hepatic RES function loss reached the 18.3 Gray (Gy) isosurface (Standard Deviation (SD) 7.7). At 6 weeks, the respective zone had increased significantly to the 12.9 Gy isosurface (SD 4.4). After 12 and 24 weeks, the dysfunction of liver volume decreased significantly to the 15 Gy and 20.4 Gy isosurface respectively (SD 7.1 and 10.0). Comparison to the hepatocyte function loss indicates a higher minimal threshold dose of the hepatic RES.Hepatic RES demonstrated a high regenerative capacity and a higher minimal threshold dose than hepatocytes. Temporary function loss was found from the 13 Gy isosurface.