Onboard cone-beam CT (CBCT) has been widely used in image guided radiation therapy. However, the longitudinal coverage is only 15.5 cm in the pelvis scan mode. As a result, a single CBCT scan cannot cover the planning target volume in the longitudinal direction for over 80% of the patients. The common approach is to use double- or multiple-circular scans and then combine multiple CBCT volumes a...

Four methodologies were evaluated for quantifying kilovoltage cone-beam computed tomography (CBCT) dose: the Cone-Beam Dose Index (CBDI), IAEA Report 5 recommended methodology (IAEA), the AAPM Task Group 111 methodology (TG111), and the current dose metric; the Computed Tomography Dose Index (CTDI) on two commercial Varian cone-beam CT imaging systems; the Clinac iX On-Board Imager (OBI); and t...

INTRODUCTION The aim of this study was to evaluate the accuracy of two imaging methods in diagnosing apical periodontitis (AP) using histopathological findings as a gold standard. METHODS The periapex of 83 treated or untreated roots of dogs' teeth was examined using periapical radiography (PR), cone-beam computed tomography (CBCT) scans, and histology. Sensitivity, specificity, predictive va...

OBJECTIVE To test the accuracy of a mathematical model (algorithm) that corrects measurements made on conventional lateral head films to corresponding dimensions observed in a cone beam computed tomography (CBCT) scan in human subjects. MATERIALS AND METHODS Thirteen subjects had lateral cephalograms taken with a conventional cephalometric machine as well as a CBCT scan. Measurements of midfa...

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...

background and aims. the imaging techniques commonly used for foreign body detection include plain radiography, xeroradiography, computed tomography (ct) scans, magnetic resonance imaging (mri) and ultrasonography. the aim of the present study was to compare cone-beam computed tomography (cbct) with conventional ct scan in determination of the exact location of a foreign body in the maxillofaci...

PURPOSE Recent clinical trials and animal studies have indicated that the tissue sensitivity to radiation induced lung injury (RILI) may be region- specific. In this study, we propose a new 4D cone beam CT (CBCT) basedcompliance imaging method to measure regional pulmonary function change in precisely irradiated small animal under CBCT guidance on small animal radiation research platform (SARRP...

This study evaluated whether measurements on conventional frontal radiographs are comparable with measurements on cone beam computed tomography (CBCT)-constructed frontal cephalometric radiographs taken from dry human skulls. CBCT scans and conventional frontal cephalometric radiographs were made of 40 dry skulls. With I-Cat Vision((R)) software, a cephalometric radiograph was constructed from ...

OBJECTIVES To describe a cadaveric temporal bone model of labyrinthitis ossificans and investigate the utility of intraoperative cone-beam computed tomography (CBCT) in the facilitating cochlear implantation. DESIGN Cadaveric temporal bone study. METHODS Five cadaveric heads had cement introduced into the 10 cochleas. CBCT and a conventional CT scan were compared to assess the extent of coc...