background: the electron contamination may reduce or even diminish the skin sparing property of the megavoltage beam. the detailed characteristics of contaminant electrons are presented for different field sizes and cases. materials and methods: the monte carlo code, mcnpx, has been used to simulate 18 mv photon beam from a varian linac-2300 accelerator. all dose measurements were carried out u...

In this chapter we will review the use of x-ray computed tomography (CT) scanning in the field of archaeology. The story will be told in roughly chronological order, starting with the first reported use of a CT scanner in the field of archaeology and then look at some some possibilities for the future. Since the introduction of the x-ray CT scanner in the 1970’s the quality of the images has st...

Chen, Yi-Ting Ph.D., Purdue University, May 2015. Laser Scanner Jitter Characterization, Page Content Analysis for Optimal Rendering, and Understanding Image Graininess. Major Professor: Jan P. Allebach. In Chapter 1, the electrophotographic (EP) process is widely used in imaging systems such as laser printers and office copiers. In the EP process, laser scanner jitter is a common artifact that...

Breast imaging represents a relatively recent and promising field of application of quantitative diffusion-MRI techniques. In view of the importance of guaranteeing and assessing its reliability in clinical as well as research settings, the aim of this study was to specifically characterize how the main MR scanner system-related factors affect quantitative measurements in diffusion-MRI of the b...

UNLABELLED We developed a prototype system to evaluate the feasibility of using a PET insert device to achieve higher resolution from a general-purpose animal PET scanner. METHODS The system consists of a high-resolution PET detector, a computer-controlled rotation stage, and a custom mounting plate. The detector consists of a cerium-doped lutetium oxyorthosilicate array (12 x 12 crystals, 0....

March 04, 2005 | MRI [1] The introduction of high-field MR systems for intraoperative guidance brings neurointervention to new levels. Although it is pricey and complex compared with previous technology, high-field MR may eventually prove cost-effective by helping neurosurgeons achieve better results, reduce patient complications, and cultivate partnerships with other specialists through better...