Aims Colonic wall thickening (“colitis”) is often reported on CT scans and poses a dilemma on whether colonoscopy is required. Previous studies show that CT “colitis” has a correlation of 69% with abnormal colonoscopic findings. We aimed to correlate CT findings of colitis with colonoscopy findings.

The selection of patients with intermediate stage hepatocellular carcinoma (HCC) for transarterial therapies currently relies on liver function and tumor properties. Outcome prediction by circulating biomarker is desirable, but not established. The aim of this study was to assess experimental HCC biomarkers for their association with survival after transarterial therapies.

A fracture or a pseudarthrosis of the processus anterior calcanei (PAC) as well as a traumatized Os calcaneus secundarius (OCS) is often overlooked. A clinical or conventional radiological differentiation of these is uncertain. Therefore, a CT scan is recommended. The aim of the study was to identify CT morphological differentiators between OCS and pathologies of PAC. All CT scans at our trauma center level I from 2010 to 2014, which imaged the entire foot, performed after acute trauma or postoperative control were retrospectively re-examined for OCS, other accessory ossicles (oAOS), fracture or pseudarthrosis of PAC and analyzed for specifiers. In 611 CT examinations, 14 (2.3%) accessory ossicles (AOS) at the PAC were detected. 12 (86%) were identified as typical OCS and 2 (14%) as oAOS. 56 (9.2%) pathologies were detected. Of these, 44 (79%) were declared as fractures and 12 (21%) as pseudarthrosis. 7 OCS (58%) and 25 (46%) of the pathologies were not mentioned in the initial CT reports. The main differentiators of OCS to fracture of PAC were the anteromedial localization into a concave notch at the calcaneal facet at PAC and the continuous corticalization. With increasing size, radiological osteoarthritic signs at the OCS were frequent (p ≤ 0.05). The study confirms that AOS or pathologies at the PAC often are not exactly described in CT report. In the context of foot trauma, attention should be paid to this region. Based on the presented differentiation criteria, a precise distinction can be made with the help of a CT.

The goal of our study was to evaluate the current approach in prediction of postoperative major complications after pancreaticoduodenectomy (PD), especially symptomatic pancreatic fistula (POPF), using parameters derived from computed tomography (CT). Patients after PD were prospectively collected in a database of the local department of surgery and all patients with CT scans available were assessed in this study. CT parameters were measured at the level of the intervertebral disc L3/L4 and consisted of the areas of the visceral adipose tissue (AVAT), the diameters of the pancreatic parenchyma (DPP) and the pancreatic duct (DPD), the areas of ventral abdominal wall muscle (AMVEN), psoas muscle (AMPSO), paraspinal muscle (AMSPI), total muscle (AMTOT), as well as the mean muscle attenuation (MA) and skeletal muscle index (SMI). Mann-Whitney-U Test for two independent samples and binary logistic regression were used for statistical analysis. One hundred thirty-nine patients (55 females, 84 males) were included. DPD was 2.9 mm (Range 0.7–10.7) on median and more narrow in patients with complications equal to or greater stadium IIIb (p < 0.04) and severe POPF (p < 0.01). DPP median value was 17 (6.9–37.9) mm and there was no significant difference regarding major complications or POPF. AVAT showed a median value of 127.5 (14.5–473.0) cm2 and was significantly larger in patients with POPF (p < 0.01), but not in cases of major complications (p < 0.06). AMPSO, AMSPI, AMVEN and AMTOT showed no significant differences between major complications and POPF. MA was both lower in groups with major complications (p < 0.01) and POPF (p < 0.01). SMI failed to differentiate between patients with or without major complications or POPF. Besides the known factors visceral obesity and narrowness of the pancreatic duct, the mean muscle attenuation can easily be examined on routine preoperative CT scans and seems to be promising parameter to predict postoperative complications and POPF.

Recently, biliary tract intraductal papillary mucinous neoplasm (IPMN) was described as a rare but important preinvasive lesion coinciding with pancreatic IPMN [1]. Several studies have revealed dysregulated molecular pathways involving mutations of the GNAS and KRAS genes and have tried to distinguish between biliary IPMN and pancreatic IPMN by means of their mucin-subtype pattern [2]. Nevertheless, the majority of data on biliary tract IPMNs come from retrospective studies, mostly where surgical interventions were performed [3]. Only one case report has so far described a combined chemoradiotherapy approach in a patient with synchronous biliary tract and pancreatic IPMNs [4].

Ziel dieser Arbeit ist es, die Effektivität der Behandlung von Osteoidosteomen (OO) mittels Radiofrequenzablation (RFA) zu untersuchen. Dabei werden insbesondere die Rezidivrate und die Verbesserung der Lebensqualität durch die Reduktion der Schmerzintensität bewertet. Retrospektive Analyse von 26 Patienten nach RFA eines OO und prospektive Analyse von 14 Patienten mittels eines selbstentwickelten Fragebogens zur Lebensqualität. Es erfolgte die Aufarbeitung des Fragebogens, der elektronischen Patientenakte und der histopathologischen Befunde. Durchschnittlich vergangen 22 Monate zwischen erstem Auftreten von Beschwerden und der ursächlichen Therapie mittels RFA. Nach der RFA zeigte sich eine signifikante Reduktion der Schmerzsymptomatik und damit eine Steigerung der Lebensqualität. Unsere Ergebnisse bestätigen, dass die RFA von OO ein sicheres und effizientes Therapieverfahren ist. Um lange konservative Therapieversuche zu vermeiden und Auswirkungen auf das muskuloskeletale System zu vermindern, sollte nach Diagnosestellung eine zeitnahe RFA des OO erfolgen.

To evaluate the technical and clinical utility of a fully MRI-compatible, pneumatically driven remote-controlled manipulator (RCM) for targeted biopsies of the prostate at 1.5 T. The data of the first 22 patients that were biopsied under robotic assistance were analyzed. Interventional planning relied on T2-weighted (T2w) turbo spin-echo (TSE) images (axial and sagittal) with a high-b-value diffusion-weighted acquisition added in selected cases. Alignment of the needle guide was controlled with a short balanced SSFP sequence in two oblique planes along the MR-visible sheath. Signals were acquired with a combination of elements from a 30-channel body and a 32-channel spine coil. Biopsy samples were taken with a fully automatic 18-G biopsy gun with a length of 150 or 175 mm. Mean age was 66.6 years and average PSA level was 11.5 ng/ml. Fourteen out of 22 patients (63%) had received prior biopsies under transrectal ultrasound guidance. Diagnostic MRI reports (before biopsy) involved 17 cases with a single suspicious finding (four PI-RADS 3, one PI-RADS 3–4, eight PI-RADS 4 and nine PI-RADS 5 cases). The median effective procedure time was 33.9 (range 25.0–55.9) min for 16 cases with one CSR and 63.4 (52.7–81.8) min for 5 cases with two CSRs. The biopsy with three CSRs took 74.0 min. Histopathologic examination revealed prostate cancer in 14 of 22 cases. MR-targeted, transrectal biopsy of the prostate could be reliably performed with a robotic manipulator at a field strength of 1.5 T. Balanced SSFP imaging is considered a viable option for fast procedural control. Follow-up work needs to evaluate to what extent in-bore adjustments and workflow enhancements will contribute to shorter procedure times or higher patient comfort.

Purpose: The aim of this study was to compare Prostate Imaging Reporting and Data System (PI-RADS) versions v1 and v2 for the detection of prostate cancer (PCa) in multiparametric MRI (mpMRI) using whole-mount histological workup as reference standard. Material and methods: MRI data of 40 patients with positive transrectal ultrasound-guided biopsy were analyzed retrospectively by two blinded readers (5 and 4 years' experience) with PI-RADS v1 and v2 for cancer-suspicious lesions. Prior to radical prostatectomy, patients had undergone IRB-approved mpMRI at 3T according to PI-RADS recommendations: T2-weighted (T2w), diffusion-weighted (DWI) and dynamic contrast-enhanced (DCE) imaging. The reference standard was provided by whole-mount sections of the prostatectomy specimens. Versions v1 and v2 were compared with respect to sensitivity and positive predictive value (PPV) per lesion. Subgroups stratified by tumor location (peripheral vs. transition zone) and aggressiveness (high vs. low grade) were also analyzed. We also evaluated the concordance of the dominant MRI sequence in v2 (DWI or T2w) and the highest individual score under v1. Interobserver agreement for PI-RADS v1 and v2 was assessed by Cohen's kappa statistics. Results: Reader 1 (R1) described 66 and Reader 2 (R2) 72 MRI lesions. The average Gleason score of 58 PCa lesions was 6.5 (range: 6 = 3 + 3 to 8 = 4 + 4), most of them (65.5%) located in the peripheral zone. PI-RADS v2 showed a trend towards lower sensitivities, but differences were not significant for both readers: R1 72.4% (v1) vs. 63.8% (v2) (P = 0.426) and R2 77.6% (v1) vs. 69.0% (v2) (P = 0.402). The trends were more pronounced in the transition zone and for low-grade cancers but remained insignificant (p-values from 0.313 to 0.691). Likewise, the apparent PPV differences, overall as well as in each zone, were not significant. Agreement between high-score v1 and dominant v2 sequence was 48% for R1 and 53% for R2. Cohen's kappa of PCa detection for two readers was 0.48 for both v1 and v2. Conclusion: Our findings indicate that the simplified, zone-specific approach of PI-RADS v2 (2015) for MRI assessment of prostate cancer may not necessarily be better than the original v1 criteria (2012). In specific cases, a strict interpretation of v2 criteria may even lead to false-negative findings. Therefore, the current PI-RADS criteria should be reconsidered, despite the low statistical evidence here.

BACKGROUND/AIMS:The position of the tip of tunnelled haemodialysis (HD) catheters (THC) might influence flow characteristics during HD. In chest X-ray (CXR), carina-related landmarks may be practicable to verify the THC position, and tip-carina distance (TCD) might be useful to predict early-flow dysfunctions. METHODS:In this single-centre, retrospective study, the TCD and the angle between the distal catheter and the body vertical axis (tip-body vertical-angle [TVA]) was measured in 115 THC by post-procedure CXR with 2 investigators. The parameters were proved to be feasible by interrater-reliability and correlated with the incidence of flow-dysfunction within 10 days after insertion. RESULTS:Steep-aligned (TVA <40°, p < 0.01) and deep-ending catheters (TCD: right-sighted >1.5 cm or left-sighted >4.5 cm below the carina; p < 0.01) showed a significantly less dysfunction with a good interrater-reliability (R[TVA] = 0.8, R[TCD] = 0.9). CONCLUSIONS:Carina-related landmarks in CXR might be helpful to predict early-flow dysfunctions. However, randomized studies will be necessary to confirm this in fluoroscopic-guided placement during the insertion of THC.

Efficient image guidance is the basis for minimally invasive interventions. In comparison with X-ray, computed tomography (CT), or ultrasound imaging, magnetic resonance imaging (MRI) provides the best soft tissue contrast without ionizing radiation and is therefore predestined for procedural control. But MRI is also characterized by spatial constraints, electromagnetic interactions, long imaging times, and resulting workflow issues. Although many technical requirements have been met over the years-most notably magnetic resonance (MR) compatibility of tools, interventional pulse sequences, and powerful processing hardware and software-there is still a large variety of stand-alone devices and systems for specific procedures only.Stereotactic guidance with the table outside the magnet is common and relies on proper registration of the guiding grids or manipulators to the MR images. Instrument tracking, often by optical sensing, can be added to provide the physicians with proper eye-hand coordination during their navigated approach. Only in very short wide-bore systems, needles can be advanced at the extended arm under near real-time imaging. In standard magnets, control and workflow may be improved by remote operation using robotic or manual driving elements.This work highlights a number of devices and techniques for different interventional settings with a focus on percutaneous, interstitial procedures in different organ regions. The goal is to identify technical and procedural elements that might be relevant for interventional guidance in a broader context, independent of the clinical application given here. Key challenges remain the seamless integration into the interventional workflow, safe clinical translation, and proper cost effectiveness.

Der Verlust der Skelettmuskulatur (Sarkopenie) ist eine Komplikation der Leberzirrhose, die mit einer hohen Sterblichkeit assoziiert ist. Es ist momentan unklar, mit welcher Verlässlichkeit Muskelparameter Zirrhose-assoziierte Komplikationen voraussagen und in welchem Ausmaß das Geschlecht einen Einfluss auf die Prävalenz und das Ausmaß der Sarkopenie hat.

Bariatric surgery and other therapeutic options for obese patients are often evaluated by the loss of weight, reduction of comorbidities or improved quality of life. However, little is currently known about potential therapy-related changes in the adipose tissue of obese patients. The aim of this study was therefore to quantify fat fraction (FF) and T1 relaxation time by magnetic resonance imaging (MRI) after Roux-en-Y gastric bypass surgery and compare the resulting values with the preoperative ones. Corresponding MRI data were available from 23 patients (16 females and 7 males) that had undergone MRI before (M0) and one month after (M1) bariatric surgery. Patients were 22-59 years old (mean age 44.3 years) and their BMI ranged from 35.7-54.6 kg/m2 (mean BMI 44.6 kg/m2) at M0. Total visceral AT volumes (VVAT-T, in L) were measured by semi-automatic segmentation of axial MRI images acquired between diaphragm and femoral heads. MRI FF and T1 relaxation times were measured in well-defined regions of visceral (VAT) and subcutaneous (SAT) adipose tissue using two custom-made analysis tools. Average BMI values were 45.4 kg/m2 at time point M0 and 42.4 kg/m2 at M1. Corresponding VVAT-T values were 5.94 L and 5.33 L. Intraindividual differences in both BMI and VVAT-T were highly significant (p<0.001). Average relaxation times T1VAT were 303.7 ms at M0 and 316.9 ms at M1 (p<0.001). Corresponding T1SAT times were 283.2 ms and 280.7 ms (p = 0.137). Similarly, FFVAT differences (M0: 85.7%, M1: 83.4%) were significant (p <0.01) whereas FFSAT differences (M0: 86.1, M1: 85.9%) were not significant (p = 0.517). In conclusion, bariatric surgery is apparently not only related to a significant reduction in common parameters of adipose tissue distribution, here BMI and total visceral fat volume, but also significant changes in T1 relaxation time and fat fraction of visceral adipose tissue. Such quantitative MRI measures may potentially serve as independent biomarkers for longitudinal and cross-sectional measurements in obese patients.

Bestimmung der primären Erfolgsrate, der prozeduralen und materialbedingten Komplikationen bei Perkutanen Radiologischen Gastrostomien (PRG) unter Verwendung einer neuartigen Sonde mit niedrigem Profil und der Vergleich mit einer historischen Kontrollgruppe.

Summary Background Loss of skeletal muscle mass is a recognised complication with a prognostic impact in patients with cirrhosis. Aim To explore in a retrospective analysis which muscle compartment most reliably predicts the occurrence of cirrhosis‐associated complications and if there are gender‐related differences. Methods 795 patients with cirrhosis listed for liver transplantation between 2001 and 2014 met the inclusion and exclusion criteria including an abdominal CT scan (±200). Controls were 109 patients who underwent a CT scan after polytrauma. The paraspinal muscles index (PSMI), the abdominal wall muscles index (AWMI) and its combination skeletal muscle index (SMI) were assessed at L3/L4, normalised to the height (cm 2 /m 2 ). Results 62.0% of patients with cirrhosis had alcoholic liver disease, and 70.6% were male. As compared to controls, a reduction in PSMI and SMI but not AWMI was associated with high model of end‐stage liver disease (MELD) score, high Child‐Pugh class, and the presence or history of cirrhosis‐associated complications in males but not females. PSMI independently predicted the occurrence of bacterial infections (HR 0.932), spontaneous bacterial peritonitis (HR 0.901), hepatic encephalopathy (HR 0.961), and hepatorenal syndrome (HR 0.946) by multivariate Cox regression analysis in a gender‐independent manner. Post‐transplant survival was not associated with the PSMI; neither AWMI nor SMI predicted any clinical endpoints. Conclusions This study links muscle wasting in patients with cirrhosis predominantly to males. However, the presence of a low PSMI mass is a gender‐independent predictor of developing cirrhosis‐associated complications and death. Scores combining the MELD with muscle parameters should be re‐validated by utilizing the PSMI.

Introduction: MRI is an emerging method in obesity research for the quantification of fat content in various body regions. The aim of this study was to determine the accuracy of MR fat-water imaging and MR spectroscopy for fat quantification at 1.5 T in oil-in-water phantoms. Material and Methods: Oil-in-water emulsions were fabricated over the entire range of lipid content (0%–100%). Relative lipid content was then assessed by two-point Dixon MRI, multi-echo Dixon MRI and single-voxel proton MR spectroscopy (SV-MRS) with localization by both stimulated echo acquisition (STEAM) and point-resolved spectroscopy (PRESS). Linear regression and Bland-Altman analyses were used for statistical evaluation of the results. Results: Agreement between MR-derived measures of lipid content and nominal values in phantoms was generally good. Agreement for two-point Dixon was moderate only (R2 = 0.75) here, especially for lipid contents between 30% and 70%. For multi-echo Dixon, STEAM and PRESS MRS, the coefficients of determination were very high (rounded R2 = 0.98 for all). Discussion: In conclusion, this work complements previous studies of MR-based fat quantification at 1.5 T and shows that multi-echo Dixon MRI and MR spectroscopy provide close results over the full range of lipid contents.

Neben proprietären Softwarepaketen kommen in Studien und Forschung häufig unterschiedliche, zum Teil nicht-kommerzielle Softwareprogramme zur Bildanalyse zum Einsatz. Die Werkzeuge sind oft nicht einheitlich, wenig konfigurierbar oder erfordern Spezialwissen. Die Anwendung wird dadurch fehleranfällig und eine fortlaufende Softwarepflege ist aufwändig. Zur Lösung stellen wir ein Software-Framework (Dicomflex) für die Erstellung von Tools für gängige, radiologische Fragestellungen vor.

Ziel war die vorläufige technische und klinische Evaluation eines MR-kompatiblen, pneumatisch gesteuerten Assistenzsystems für In-Bore-Prostatabiopsien (PBx) bei 1,5 T.