There is a serious and growing concern about the CT dose delivered by diagnostic CT examinations or image-guided radiation therapy imaging procedures. To better understand and to accurately quantify radiation dose due to CT imaging, Monte Carlo based CT scanner models are needed. This dissertation describes the development, validation, and application of detailed CT scanner models including a G...

Respiratory monitoring systems are required to supply CT scanners with information on the patient's breathing during the acquisition of a respiration-correlated computer tomography (RCCT), also referred to as 4D CT. The information a respiratory monitoring system has to provide to the CT scanner depends on the specific scanner. The purpose of this study is to compare two different respiratory m...

Introduction: Computed tomography (CT) has numerous applications in clinical procedures but its main problem is its high radiation dose to the patients compared to other imaging modalities using x-ray. CT delivers approximately high doses to the nearby tissues due to the scattering effect, fan beam (beam divergence) and limited collimator efficiency. The radiation dose from multi-slice scanners...

Introduction: Mini Computed Tomography (mini-CT) was suggested in biomedical research to investigate tissues and small animals. We present designed and built a mini x-ray computed tomography (mini-CT) for small animals as well as industrial component imaging. Materials and Methods: The system used in this study includes a X-ray tube 20kV to 160kV and a flat pa...

PURPOSE The development of flat panel detector technology has resulted in renewed interest in the possibility of generating CT-like images from rotational angiographic acquisitions. At least two commercial products now use cone beam reconstruction software in conjunction with flat panel detectors to produce such images. The purpose of the work presented here is to report on image quality obtain...

The objective of this study was to compare the volume three-dimensional (3D) models generated by different scanners and computational modeling protocols. Eight dry mandibles were scanned five computed tomography (CT) a 3D-scanner. Three-dimensional generated, received surface treatment processes, final 3D compared. results show that there no significant difference among CT techniques, however, ...

this article is intended to provide an overview of various aspects of clinical pet/ct. these include discussions of: (i) important areas of clinical application; (ii) opportunities in clinical research; (iii) scanner and operating-mode considerations (e.g. bgo vs. lso, lyso or gso scanners, 2d vs. 3d imaging). (iv) study-specific considerations (e.g. patient preparation and positioning issues, ...

Materials and Methods. The coach-mounted system consists of a seven-degrees-of-freedom, passive mounting arm; a remote-center-of-motion robot; and a motorized, radiolucent needle-insertion device to deliver 17–18-gauge implant and biopsy needles into the prostate with the transperineal route. The robot is registered to the image space with a stereotactic adapter. The surgeon plans and controls ...

Many image guided surgical (IGS) procedures use surface representations of anatomical features to provide a registration between physical space and image space. While anatomical fiducial registration techniques can often be compromised by soft tissue deformation, laser-scanning systems offer a non-contact method for accurately resolving geometric surfaces. This digitization approach is particul...