Publications by authors named "Maarten Niekel"

Introduction And Purpose: Flat detector computed tomography (FD-CT) technology is becoming more widely available in the angiography suites of comprehensive stroke centers. In patients with acute ischemic stroke (AIS), who are referred for endovascular therapy (EVT), FD-CT generates cerebral pooled blood volume (PBV) maps, which might help in predicting the final infarct area. We retrospectively analyzed pre- and post-recanalization therapy quantitative PBV measurements in both the infarcted and hypoperfused brain areas of AIS patients referred for EVT.

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C-arm flat-panel detector computed tomographic (CT) imaging in the angiography suite increasingly plays an important part during interventional neuroradiological procedures. In addition to conventional angiographic imaging of blood vessels, flat detector CT (FD CT) imaging allows simultaneous 3D visualization of parenchymal and vascular structures of the brain. Next to imaging of anatomical structures, it is also possible to perform FD CT perfusion imaging of the brain by means of cerebral blood volume (CBV) or pooled blood volume (PBV) mapping during steady state contrast administration.

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En bloc resection of the thoracic duct compartment enhances adequate lymph node removal and may improve oncologic outcomes in esophagectomy for malignant esophageal diseases. However, it also increases the risk of postoperative chylothorax, with a reported incidence of 5% to 20%. This report describes a technique that facilitates intraoperative identification of the thoracic duct, as well as proximal and distal ligation, during robot-assisted esophagectomy by lymphangiography-guided injection of indocyanine green in the right groin in a patient in the left lateral position.

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Primary tumors have a high likelihood of developing metastases in the liver, and early detection of these metastases is crucial for patient outcome. We propose a method based on convolutional neural networks to detect liver metastases. First, the liver is automatically segmented using the six phases of abdominal dynamic contrast-enhanced (DCE) MR images.

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Background: Heterotopic ossification (HO) is a common extrinsic cause of elbow stiffness after trauma. However, factors associated with the development of HO are incompletely understood.

Questions/purposes: We retrospectively identified (1) patient-related demographic factors, (2) injury-related factors, and (3) treatment-related factors associated with the development of HO severe enough to restrict motion after surgery for elbow trauma.

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Purpose: To obtain diagnostic performance values of computed tomography (CT), magnetic resonance (MR) imaging, fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET), and FDG PET/CT in the detection of colorectal liver metastases in patients who have not previously undergone therapy.

Materials And Methods: A comprehensive search was performed for articles published from January 1990 to January 2010 that fulfilled the following criteria: a prospective study design was used; the study population included at least 10 patients; patients had histopathologically proved colorectal cancer; CT, MR imaging, FDG PET, or FDG PET/CT was performed for the detection of liver metastases; intraoperative findings or those from histopathologic examination or follow-up were used as the reference standard; and data for calculating sensitivity and specificity were included. Study design characteristics, patient characteristics, imaging features, reference tests, and 2 × 2 tables were recorded.

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Purpose: In an attempt to shorten the questionnaires given to patients in both clinical and research settings, we studied whether the correlation of commonly used psychological measures was comparable for the standard Disabilities of the Arm, Shoulder, and Hand (DASH) and the shorter QuickDASH questionnaires.

Methods: A cohort of 839 patients with carpal tunnel syndrome, trigger finger, de Quervain's disease, trapeziometacarpal arthrosis, lateral epicondylosis, or a distal radius fracture 2 weeks after surgery, who completed the DASH and 1 or more measures of psychological distress, was created from 10 databases from previously implemented studies. Correlations of the DASH and the QuickDASH with several measures of psychological factors (Center for Epidemiologic Studies Depression Scale [CES-D], Pain Catastrophizing Scale [PCS], and Pain Anxiety Symptoms Scale [PASS-40]) were calculated in both univariate and multivariable analyses.

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