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Objectives: To compare the value of functional future liver remnant (functFLR) to established clinical and imaging variables in prediction of post-hepatectomy liver failure (PHLF) after major liver resection., Methods: This retrospective, cross-sectional study included 62 patients, who underwent gadoxetic acid enhanced MRI and MDCT within 10 weeks prior to resection of ≥ 4 liver segments. Future liver remnant (FLR) was measured in MDCT using semi-automatic software. Relative liver enhancement for each FLR segment was calculated as the ratio of signal intensity of parenchyma before and 20 min after i.v. administration of gadoxetic acid and given as mean (remnantRLE). Established variables included indocyanine green clearance, FLR, proportion of FLR, weight-adapted FLR and remnantRLE. functFLR was calculated as FLR multiplied by remnantRLE and divided by patient's weight. The association of measured variables and PHLF was tested with univariate and multivariate logistic regression analysis and receiver operator characteristics (ROC) curves compared with the DeLong method., Results: Sixteen patients (25.8%) experienced PHLF. Univariate logistic regression identified FLR (p = 0.015), proportion of FLR (p = 0.004), weight-adapted FLR (p = 0.003), remnantRLE (p = 0.002) and functFLR (p = 0.002) to be significantly related to the probability of PHLF. In multivariate logistic regression analysis, a decreased functFLR was independently associated with the probability of PHLF (0.561; p = 0.002). Comparing ROC curves, functFLR showed a significantly higher area under the curve (0.904; p < 0.001) than established variables., Conclusions: functFLR seems to be superior to established variables in prediction of PHLF after major liver resection., Key Points: • functFLR is a parameter combining volumetric and functional imaging information, derived from MDCT and gadoxetic acid enhanced MRI. • In comparison to other established methods, functFLR is superior in prediction of post-hepatectomy liver failure. • functFLR could help to improve patient selection prior major hepatic surgery.

Objective: The aim of this study was to investigate the impact of portal hypertension (PH) on gadoxetic acid-enhanced liver magnetic resonance imaging (MRI) and assess diagnostic and prognostic implications in comparison to established imaging features of PH., Materials and Methods: Institutional review board-approved retrospective study of 178 patients (142 men; median age, 59.4 years) with chronic liver disease undergoing MRI and hepatic venous pressure gradient (HVPG) measurement between January 2008 and April 2015. Magnetic resonance imaging was assessed for established features of PH (splenic and portal vein diameters, portosystemic collaterals, ascites) and for features on 20 minutes delayed T1-weighted gadoxetic acid-enhanced MRI, that is, relative liver enhancement (RLE), biliary contrast excretion, or portal vein hyperintensity or isointensity (ie, portal vein hyperintensity sign, PVHS). Statistics encompassed linear regression, logistic regression, and survival analysis., Results: There was an inverse correlation between HVPG and RLE (r = 0.18, P < 0.0001). On univariate analysis, clinically significant PH (ie, HVPG ≥ 10 mm Hg, n = 109) and severe PH (ie, HVPG ≥ 12 mm Hg, n = 99) were associated with delayed biliary contrast excretion (n = 33) and the PVHS (n = 74) (P < 0.01 for all). Multivariate analysis demonstrated significant associations between the PVHS and severe PH (odds ratio [OR], 3.33; P = 0.008), independently of spleen size (OR, 1.26; P = 0.002), portosystemic collaterals (n = 81; OR, 5.46; P = 0.0001), and ascites (n = 88; OR, 3.24; P = 0.006). Lower RLE and the PVHS were associated with lower 3-year, transplantation-free survival (hazards ratios, 0.98 and 3.99, respectively, P = 0.002 for all), independently of the Child-Pugh and Model for End-Stage Liver Disease scores., Conclusions: The presence of the PVHS on gadoxetic acid-enhanced MRI is an independent indicator of severe PH and may enable more accurate diagnosis. This feature and decreased hepatic contrast uptake may also comprise prognostic information.

Objectives: To evaluate the prognostic relevance of temporal muscle thickness (TMT) in brain metastasis patients., Methods: We retrospectively analysed TMT on magnetic resonance (MR) images at diagnosis of brain metastasis in two independent cohorts of 188 breast cancer (BC) and 247 non-small cell lung cancer (NSCLC) patients (overall: 435 patients)., Results: Survival analysis using a Cox regression model showed a reduced risk of death by 19% with every additional millimetre of baseline TMT in the BC cohort and by 24% in the NSCLC cohort. Multivariate analysis included TMT and diagnosis-specific graded prognostic assessment (DS-GPA) as covariates in the BC cohort (TMT: HR 0.791/CI [0.703-0.889]/p < 0.001; DS-GPA: HR 1.433/CI [1.160-1.771]/p = 0.001), and TMT, gender and DS-GPA in the NSCLC cohort (TMT: HR 0.710/CI [0.646-0.780]/p < 0.001; gender: HR 0.516/CI [0.387-0.687]/p < 0.001; DS-GPA: HR 1.205/CI [1.018-1.426]/p = 0.030)., Conclusion: TMT is easily and reproducibly assessable on routine MR images and is an independent predictor of survival in patients with newly diagnosed brain metastasis from BC and NSCLC. TMT may help to better define frail patient populations and thus facilitate patient selection for therapeutic measures or clinical trials. Further prospective studies are needed to correlate TMT with other clinical frailty parameters of patients., Key Points: • TMT has an independent prognostic relevance in brain metastasis patients. • It is an easily and reproducibly parameter assessable on routine cranial MRI. • This parameter may aid in patient selection and stratification in clinical trials. • TMT may serve as surrogate marker for sarcopenia.

Objectives: Eye movements are the physical expression of upper fetal brainstem function. Our aim was to identify and differentiate specific types of fetal eye movement patterns using dynamic MRI sequences. Their occurrence as well as the presence of conjugated eyeball motion and consistently parallel eyeball position was systematically analyzed., Methods: Dynamic SSFP sequences were acquired in 72 singleton fetuses (17-40 GW, three age groups [17-23 GW, 24-32 GW, 33-40 GW]). Fetal eye movements were evaluated according to a modified classification originally published by Birnholz (1981): Type 0: no eye movements; Type I: single transient deviations; Type Ia: fast deviation, slower reposition; Type Ib: fast deviation, fast reposition; Type II: single prolonged eye movements; Type III: complex sequences; and Type IV: nystagmoid., Results: In 95.8% of fetuses, the evaluation of eye movements was possible using MRI, with a mean acquisition time of 70 seconds. Due to head motion, 4.2% of the fetuses and 20.1% of all dynamic SSFP sequences were excluded. Eye movements were observed in 45 fetuses (65.2%). Significant differences between the age groups were found for Type I (p = 0.03), Type Ia (p = 0.031), and Type IV eye movements (p = 0.033). Consistently parallel bulbs were found in 27.3-45%., Conclusions: In human fetuses, different eye movement patterns can be identified and described by MRI in utero. In addition to the originally classified eye movement patterns, a novel subtype has been observed, which apparently characterizes an important step in fetal brainstem development. We evaluated, for the first time, eyeball position in fetuses. Ultimately, the assessment of fetal eye movements by MRI yields the potential to identify early signs of brainstem dysfunction, as encountered in brain malformations such as Chiari II or molar tooth malformations.

Clinical/methodical Issue: Evaluation and confirmation of fetal pathologies previously suspected or diagnosed with ultrasound., Standard Radiological Methods: Ultrasound and magnetic resonance imaging (MRI)., Methodical Innovations: Technique for prenatal fetal examination., Performance: Fetal MRI is an established supplementary technique to prenatal ultrasound., Achievements: Fetal MRI should only be used as an additional method in prenatal diagnostics and not for routine screening., Practical Recommendations: Fetal MRI should only be performed in perinatal medicine centers after a previous level III ultrasound examination.

Clinical/methodical Issue: Diagnosis and differential diagnosis of fetal thoracic and abdominal malformations., Standard Radiological Methods: Ultrasound and magnetic resonance imaging (MRI)., Methodical Innovations: In cases of suspected pathologies based on fetal ultrasound MRI can be used for more detailed examinations and can be of assistance in the differential diagnostic process., Performance: Improved imaging of anatomical structures and of the composition of different tissues by the use of different MRI sequences., Achievements: Fetal MRI has become a part of clinical routine in thoracic and abdominal malformations and is the basis for scientific research in this field., Practical Recommendations: In cases of thoracic or abdominal malformations fetal MRI provides important information additional to ultrasound to improve diagnostic accuracy, prognostic evaluation and surgical planning.

Aim: To evaluate the value of gadoxetic acid-enhanced T1-weighted (T1W) magnetic resonance cholangiography (MRC) versus conventional T2-weighted (T2W) MRC compared to endoscopic retrograde cholangiopancreatography (ERCP) in patients with primary sclerosing cholangitis (PSC). Materials and methods: Based on T1W MRC, PSC patients were classified into a regular (RG) and a delayed (DG) excreting group, with an absence of gadoxetic acid in the common bile duct at 20 min. Beading, pruning, and gradation of central bile duct stenosis, evaluated by T1W and T2W MRC, were compared to ERCP. Liver parenchymal enhancement was measured in both study groups and compared to a reference group (n = 20) without a history of liver disease. Two readers performed all measurements. Results: Based on beading and pruning of the peripheral bile ducts, sensitivities, specificities, and accuracies for reader 1 were 0.17/0.43, 0/0.17, and 0.15/0.31 for T1W MRC, and 0.83/0.86, 1/0.83, and 0.85/0.85 for T2W MRC (p = 0.004). For reader 2 sensitivities, specificities, and accuracies were 0.25/0.57, 0/0.33, and 0.23/0.46 for T1W MRC, and 0.92/1, 1/0.83, and 0.92/0.92 for T2W MRC (p = 0.012). Compared to ERCP, central bile duct stenoses were significantly overestimated (p < 0.001) by T2W MRC. A significantly lower parenchymal enhancement was found in the DG (n = 7) compared to the RG (n = 13), and compared to the reference group (p < 0.001). Conclusion: The combined performance of T2W and T1W MRC may provide a comprehensive imaging workup of PSC, including morphological and functional information resulting in optimal management. [Copyright &y& Elsevier]

An abstract of the conference paper "Measurements of the posterior fossa on fetal MRI in open and closed neural tube defects," by R. Woitek and colleagues is presented.