Publications by authors named "Alena Baumann"

Objectives: To assess the prognostic value of pre-therapeutic computed tomography (CT) attenuation of liver metastases for overall survival (OS) in metastatic colorectal cancer (mCRC).

Methods: In the open-label, randomised, prospective phase-III FIRE-3 trial, patients with histologically confirmed mCRC received fluorouracil (5-FU), leucovorin and irinotecan (FOLFIRI) with either cetuximab or bevacizumab. Participating patients gave written informed consent prior to study entry.

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To compare a semi-automatic software tool for the measurement of aortic annulus dimensions with manual measurements by expert readers and to analyze whether and to what extent interchangeability exists between semi-automatic and manual measurements. We retrospectively included 374 consecutive patients with high-grade aortic stenosis who had undergone CT-angiography of the heart prior to trans-catheter aortic valve replacement (TAVR). In independent analyses, two expert readers manually measured aortic annulus dimensions (long axis, short axis, circumference, area) as well as the distance of the coronary ostia from the annulus plane.

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Objectives: To empirically determine thresholds for volumetric assessment of response and progress of liver metastases in line with the unidimensional RECIST thresholds.

Methods: Patients with metastatic colorectal cancer initially enrolled in a multicentre clinical phase-III trial were included. In all CT scans, the longest axial diameters and volumes of hepatic lesions were determined semi-automatically.

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Purpose: To determine the prognostic impact of radiologically enlarged lymph nodes ≥ 10 mm on the survival of patients with metastatic colorectal cancer.

Materials And Methods: The prospective, randomized, open-label FIRE-3/AIO KRK0306 trial evaluated the first-line therapy of patients with KRAS exon 2 wild-type metastatic colorectal cancer with fluorouracil, folinic acid and irinotecan plus either cetuximab or bevacizumab. In the RAS wild-type population (n = 400), adequately evaluable baseline computed tomographies (n = 339) were reviewed for enlarged regional and distant lymph nodes.

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Purpose: The aim of this study was to investigate whether the detection of foreign bodies can be improved using dark-field and phase-contrast radiography compared with conventional (transmission) radiographs.

Materials And Methods: Experiments were performed using ex vivo pig paws, which were prepared with differently sized foreign bodies of metal, wood, and glass (n = 10 each). Paws without foreign bodies served as controls (n = 30).

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Objective: The aim of this study was to evaluate the diagnostic value of x-ray dark-field imaging in projection radiography-based depiction of pneumothoraces in the neonatal murine lung, a potentially life-threatening medical condition that requires a timely and correct diagnosis.

Materials And Methods: By the use of a unique preclinical model, 7-day-old C57Bl/6N mice received mechanical ventilation for 2 or 8 hours with oxygen-rich gas (FIO2 = 0.4; n = 24).

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Introduction: Factors that determine the extent of the penumbra in the initial diagnostic workup using whole brain CT Perfusion (WB-CTP) remain unclear. The purpose of the current study was to determine a possible dependency of the initial mismatch size between cerebral blood flow (CBF) and cerebral blood volume (CBV) from time after symptom onset, leptomeningeal collateralization, and occlusion localization in acute middle cerebral artery (MCA) infarctions.

Methods: Out of an existing cohort of 992 consecutive patients receiving multiparametric CT scans including WB-CTP due to suspected stroke, we included patients who had (1) a witnessed time of symptom onset, (2) an infarction of the MCA territory as documented by follow-up imaging, and (3) an initial CBF volume of >10 ml.

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We aimed to investigate the overall prevalence and possible factors influencing the occurrence of crossed cerebellar diaschisis after acute middle cerebral artery infarction using whole-brain CT perfusion. A total of 156 patients with unilateral hypoperfusion of the middle cerebral artery territory formed the study cohort; 352 patients without hypoperfusion served as controls. We performed blinded reading of different perfusion maps for the presence of crossed cerebellar diaschisis and determined the relative supratentorial and cerebellar perfusion reduction.

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Background And Purpose: While penumbra assessment has become an important part of the clinical decision making for acute stroke patients, there is a lack of studies measuring the reliability and reproducibility of defined assessment techniques in the clinical setting. Our aim was to determine reliability and reproducibility of different types of three-dimensional penumbra assessment methods in stroke patients who underwent whole brain CT perfusion imaging (WB-CTP).

Materials And Methods: We included 29 patients with a confirmed MCA infarction who underwent initial WB-CTP with a scan coverage of 100 mm in the z-axis.

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Background And Purpose: Vertebral artery hypoplasia (VAH) is supposed to be a risk factor for posterior circulation ischemia (PCI), particularly in the territory of the posterior inferior cerebellar artery (PICA). The aim of our study was to determine whether VAH impedes perfusion in the dependent PICA territory even in the absence of manifest PCI.

Methods: VA diameter was retrospectively measured in 934 consecutive patients who underwent whole-brain multimodal computed tomography because of suspected stroke.

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Introduction: The aim of this study was to examine reliability and reproducibility of volumetric perfusion deficit assessment in patients with acute ischemic stroke who underwent recently introduced whole-brain CT perfusion (WB-CTP).

Methods: Twenty-five consecutive patients underwent 128-row WB-CTP with extended scan coverage of 100 mm in the z-axis using adaptive spiral scanning technique. Volumetric analysis of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), time to peak (TTP), and time to drain (TTD) was performed twice by two blinded and experienced readers using OsiriX V.

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