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Objective: Brain atrophy has the potential to become a biomarker for severity of radiation-induced side-effects. Particularly brain tumour patients can show great MRI signal changes over time caused by e.g. oedema, tumour progress or necrosis. The goal of this study was to investigate if such changes affect the segmentation accuracy of normal appearing brain and thus influence longitudinal volumetric measurements. Materials and methods: T1-weighted MR images of 52 glioblastoma patients with unilateral tumours acquired before and three months after the end of radio(chemo)therapy were analysed. GM and WM volumes in the contralateral hemisphere were compared between segmenting the whole brain (full) and the contralateral hemisphere only (cl) with SPM and FSL. Relative GM and WM volumes were compared using paired t tests and correlated with the corresponding mean dose in GM and WM, respectively. Results: Mean GM atrophy was significantly higher for full segmentation compared to cl segmentation when using SPM (mean ± std: ΔVGM,full = − 3.1% ± 3.7%, ΔVGM,cl = − 1.6% ± 2.7%; p < 0.001, d = 0.62). GM atrophy was significantly correlated with the mean GM dose with the SPM cl segmentation (r = − 0.4, p = 0.004), FSL full segmentation (r = − 0.4, p = 0.004) and FSL cl segmentation (r = -0.35, p = 0.012) but not with the SPM full segmentation (r = − 0.23, p = 0.1). Conclusions: For accurate normal tissue volume measurements in brain tumour patients using SPM, abnormal tissue needs to be masked prior to segmentation, however, this is not necessary when using FSL. [ABSTRACT FROM AUTHOR]

New protocols for coronary computed tomography angiography (CCTA) could lower the radiation dose for patients but influence the image quality. To compare image quality and radiation exposure in step-and-shoot CCTA and high-pitch spiral CCTA. Fifty-nine pairs of patients matched for weight, height, sex and heart rate were included in this study (74 m, 44 f, average age 60 years, age range 29-94 years). Step-and-shoot CCTA and high-pitch spiral CCTA was performed on a third generation dual-source CT in equally sized patient groups. The signal-to-noise ratio (SNR) in the ascending aorta and the coronary arteries were determined for each dataset. Image quality was rated using a five-point scale. We used the t-test for paired samples to compare SNR and effective dose, and the Wilcoxon test to compare image quality scores. Mean effective dose for the step-and-shoot protocol (4.15 ± 3.07 mSv) was significantly higher in comparison to the high-pitch spiral protocol (1.2 ± 0.69 mSv; p < 0.0001). Mean SNR was higher with the step-and-shoot protocol compared to the high-pitch spiral protocol in the aorta, in the left main and peripheral coronary arteries (p < 0.01), in the proximal right coronary artery (p = 0.027). Image quality scores were significantly better for the step-and-shoot protocol (p = 0.0003). Step-and-shoot CCTA has significantly better SNR and overall image quality compared to high-pitch spiral CCTA, but with a mean effective dose more than thrice as high. [ABSTRACT FROM AUTHOR]

Copyright of Der Radiologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Der Nervenarzt is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents a case study of a young man with anaplastic large cell lymphoma who has received treatment with the standard salvage combination chemotherapy. The results from the positron emission tomography (PET) and magnetic resonance imaging (MRI) have shown the infiltration of cervical, para-aortic and iliac nodes. He was later on provided with crizotinib treatment. The article discusses the relevance of disease specific targeted drugs and imaging techniques in treatment of diseases.

Neoadjuvant systemic therapy may induce steatosis or sinusoid obstruction syndrome in the liver. The aim of this study was to investigate the influence of systemic therapy with irinotecan, oxaliplatin and cetuximab on conspicuity of liver metastases on computed tomography (CT). CT scans of 48 patients with initial unresectable colorectal liver metastases which were treated in a Europe-wide, opened, randomized phase II trial receiving oxaliplatin or irinotecan combined with folinic acid and cetuximab were analysed. The density of the metastases and the liver parenchyma before and after systemic therapy were analysed by region-of-interest technique and the tumour-to-liver difference (dHU TLD). The mean density of liver parenchyma and liver metastases did not vary significantly before and after neoadjuvant therapy on plain (56.3 ± 8.1 HU, 54.8 ± 13.5 HU) and arterial enhanced CT (76.0 ± 15.7 HU, 70.5 ± 20.4 HU). There was a significant reduction (105.6 ± 17.3 HU, 93.3 ± 18.2 HU) in the density of liver parenchyma on portal venous scans after systemic therapy (p < 0.0001) and a reduction of dHU TLD, consecutively. In patients with colorectal liver metastases, neoadjuvant chemotherapy may have a toxic impact on liver parenchyma resulting in reduced tumour-to-liver contrast in contrast-enhanced CT. This may lead to underestimation of real lesion size.