Academic radiology
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We evaluated the effect of gravity on intrahepatic perfusion (IHP) in patients with a port-catheter system (PCS) implanted for hepatic arterial infusion chemotherapy (HAIC). Using fused single photon-emission computed tomographic (SPECT)/computed tomographic (CT) images, we compared IHP after the injection of technetium-99m-labeled macroaggregated albumin (Tc-99m-MAA) via a PCS with the patient in the upright and decubitus positions. ⋯ Although the patient posture affected IHP by changing the position of the infusion catheter side hole in the liver, gravity had no significant effect on IHP in patients bearing an implantable PCS for the delivery of HAIC.
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Task-evoked functional MRI (fMRI) has been used successfully in the study of brain function and clinically for presurgical localization of eloquent brain regions prior to the performance of brain surgery. This method requires patient cooperation and is not useful in young children or if the patient has cognitive dysfunction or physical impairment. An alternative method that can overcome some of these disadvantages measures the intrinsic function of the brain using resting-state fMRI. This method does not require any task performance and measures the spontaneous low-frequency (<0.1 Hz) fluctuations of the fMRI signal over time. Our objective in the present work is to provide preliminary information on the possible clinical utility of this technique for presurgical planning and on possible future applications. ⋯ Resting-state fMRI data can provide valuable presurgical information in many patients who cannot benefit from traditional task-based fMRI. Adoption of this method has the potential to improve individualized patient-centered care.
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Comparative Study
Triple rule-out and dedicated coronary artery CTA: comparison of coronary artery image quality.
The aim of this study was to compare image quality on dedicated and triple rule-out coronary computed tomographic (CT) angiography (CTA) with respect to motion artifacts and the quality of coronary artery opacification. ⋯ The image quality of triple rule-out CTA is comparable to that of dedicated coronary CTA, showing no statistically significant difference in motion artifacts or opacification, and therefore may be an alternative and useful diagnostic study in a select group of emergency department patients.
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Comparative Study
3D-CT volumetry of the lung using multidetector row CT: comparison with pulmonary function tests.
The aim of this study was to evaluate the accuracy of measurements of lung volumes reconstructed using three-dimensional computed tomographic (CT) imaging from thin-section multidetector-row CT images compared to standard pulmonary function testing. ⋯ Lung volume calculated using three-dimensional CT volumetry was well correlated with lung volume measured using spirometry. Three-dimensional CT volumetry can be used to evaluate pulmonary function.
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Comparative Study
Improving performance of computer-aided detection scheme by combining results from two machine learning classifiers.
Global data-based and local instance-based machine-learning methods and classifiers have been widely used to optimize computer-aided detection and diagnosis (CAD) schemes to classify between true-positive and false-positive detections. In this study, the correlation between these two types of classifiers was investigated using a new independent testing data set, and the potential improvement of a CAD scheme's performance by combining the results of the two classifiers in detecting breast masses was assessed. ⋯ This study demonstrates that two global data-based and local data-based machine-learning classifiers (ANN and KNN) generated low correlated detection results and that combining the detection scores of these two classifiers significantly improved overall CAD performance (P < .01) and reduced standard error in CAD performance assessment.