BACKGROUND AND PURPOSE Blood flow of the internal jugular vein and intracranial venous sinuses is affected by respiratory state. The purpose of this study was to clarify the changes in flow velocity and direction and signal intensities of sigmoid sinuses on phase-contrast (PC) MR images obtained with regular breathing and with deep inspiratory breath holding. METHODS One hundred seven subject...

in this paper, we have outlined the surrogate management framework for optimization of expensive functions. an initial simple iterative method which we call the “strawman” method illustrates how surrogates can be incorporated into optimization to stand in for the most expensive function. these ideas are made rigorous by incorporating them into the framework of pattern search methods. the smf al...

dibutyl phthalate (dbp) is a phthalic acid ester and is widely used in polymeric products to make them more flexible. dbp is found in almost every plastic material and is believed to be persistent in the environment. various analytical methods have been used to measure dbp in different matrices. considering the ubiquitous nature of dbp, the most important challenge in dbp analyses is the contam...

Abstract. In cardiac MRI, ECG triggering is used or patients are required to hold their breath, to alleviate motion artifacts and deterioration of image quality. However, ECG signal quality is often suboptimal and patients may not be able to adequately hold their breath. Alternative solutions for tracking breathing and cardiac beating can open the way for robust free-breathing and ECG-less card...

BACKGROUND Our aim was to compare the apparent diffusion coefficient (ADC) values of normal abdominal parenchymal organs and signal-to-noise ratio (SNR) measurements in the same patients with breath hold (BH) and free breathing (FB) diffusion weighted imaging (DWI). MATERIAL/METHODS Forty-eight patients underwent both BH and FB DWI. Spherical region of interest (ROI) was placed on the right h...

OBJECTIVES The aim of this article was to test a simple approach of using pixel density values from fluoroscopy images to enable gated radiotherapy. METHODS Anterior and lateral (LAT) from images were acquired from 18 patients referred for radical radiotherapy for non-small cell lung cancer for a period of 30-45 s. The amplitude of movement and the number of breathing cycles were determined i...