To evaluate potential confounding factors in the quantitative assessment of liver fibrosis and cirrhosis using T1 relaxation times. Methods: The study population is based on a radiology-information-system database search for abdominal MRI performed from July 2018 to April 2019 at our institution. After applying exclusion criteria 200 (59 ± 16 yrs) remaining patients were retrospectively included. 93 patients were defined as liver-healthy, 40 patients without known fibrosis or cirrhosis, and 67 subjects had a clinically or biopsy-proven liver fibrosis or cirrhosis. T1 mapping was performed using a slice based look-locker approach. A ROI based analysis of the left and the right liver was performed. Fat fraction, R2*, liver volume, laboratory parameters, sex, and age were evaluated as potential confounding factors. Results: T1 values were significantly lower in healthy subjects without known fibrotic changes (1.5 T MRI: 575 ± 56 ms; 3 T MRI: 857 ± 128 ms) compared to patients with acute liver disease (1.5 T MRI: 657 ± 73 ms, p < 0.0001; 3 T MRI: 952 ± 37 ms, p = 0.028) or known fibrosis or cirrhosis (1.5 T MRI: 644 ± 83 ms, p < 0.0001; 3 T MRI: 995 ± 150 ms, p = 0.018). T1 values correlated moderately with the Child-Pugh stage at 1.5 T (p = 0.01, ρ = 0.35). Conclusion:T1 mapping is a capable predictor for detection of liver fibrosis and cirrhosis. Especially age is not a confounding factor and, hence, age-independent thresholds can be defined. Acute liver diseases are confounding factors and should be ruled out before employing T1-relaxometry based thresholds to screen for patients with liver fibrosis or cirrhosis.

Chemotherapy is often omitted in elderly patients with glioblastoma multiforme due to a fear of side effects. We applied metronomic chemotherapy with low-dose temozolomide and celecoxib (LD-TEM/CEL) during and after external beam radiotherapy (EBRT) and here report on how this regimen compares to standard temozolomide radiochemotherapy (SD-TEM) in elderly patients. We retrospectively analyzed records of 146 patients aged 65 years and older that underwent EBRT. Factors of interest were age, performance status, comorbidities, MGMT status, therapy (resection/biopsy, radiotherapy/dose, chemotherapy/regimen/dose), progression-free (PFS) and overall survival (OS) status. Irrespective of the regimen, addition of chemotherapy more than doubled median survival rates (EBRT only: 4.2 months; EBRT + LD-TEM/CEL: 8.5 months; EBRT + SD-TEM: 10.8 months; p ≤ 0.008). Although patients receiving metronomic LD-TEM/CEL were significantly older (62 % were ≥75 years vs. 22 %; p < 0.001), had significantly lower performance scores (50 % had a KPS <70 vs. 28 %; p = 0.049) and were significantly more comorbid (73 % had ≥4 comorbidities vs. 37 %; p = 0.002) than patients of the SD-TEM group, there were no significant differences in PFS and OS. Independent of other factors, omission of chemotherapy significantly impairs progression-free and overall survival. With all the limitations of a retrospective analysis, our data suggest that metronomic chemotherapy with LD-TEM/CEL may be equieffective and eventually better tolerated than SD-TEM. It may be offered to elderly patients that are not eligible for standard chemotherapy.

No abstract

Objectives: Ischemic stroke is a leading cause of mortality and acquired disability worldwide and thus plays an enormous health-economic role. Imaging of choice is computed-tomographic (CT) or magnetic resonance imaging (MRI), especially diffusion-weighted (DW) sequences. However, MR imaging is associated with high costs and therefore has a limited availability leading to low-field-MRI techniques increasingly coming into focus. Thus, the aim of our study was to assess the potential of stroke imaging with low-field MRI. Material and Methods: A scanner comparison was performed including 27 patients (17 stroke cohort, 10 control group). For each patient, a brain scan was performed first with a 1.5T scanner and afterwards with a 0.55T scanner. Scan protocols were as identical as possible and optimized. Data analysis was performed in three steps: All DWI/ADC (apparent diffusion coefficient) and FLAIR (fluid attenuated inversion recovery) sequences underwent Likert rating with respect to image impression, resolution, noise, contrast, and diagnostic quality and were evaluated by two radiologists regarding number and localization of DWI and FLAIR lesions in a blinded fashion. Then segmentation of lesion volumes was performed by two other radiologists on DWI/ADC and FLAIR. Results: DWI/ADC lesions could be diagnosed with the same reliability by the most experienced reader in the 0.55T and 1.5T sequences (specificity 100% and sensitivity 92.9%, respectively). False positive findings did not occur. Detection of number/location of FLAIR lesions was mostly equivalent between 0.55T and 1.5T sequences. No significant difference (p = 0.789–0.104) for FLAIR resolution and contrast was observed regarding Likert scaling. For DWI/ADC noise, the 0.55T sequences were significantly superior (p < 0.026). Otherwise, the 1.5T sequences were significantly superior (p < 0.029). There was no significant difference in infarct volume and volume of infarct demarcation between the 0.55T and 1.5T sequences, when detectable. Conclusions: Low-field MRI stroke imaging at 0.55T may not be inferior to scanners with higher field strengths and thus has great potential as a low-cost alternative in future stroke diagnostics. However, there are limitations in the detection of very small infarcts. Further technical developments with follow-up studies must show whether this problem can be solved.