Bai et al. recently proposed to acquire random fanbeam/cone-beam projections with a linear/planar detector from a circular scanning locus for controlled cardiac computed tomography (CT). After specifying a uniform acquisition geometry required by FBP (filtration-backprojection), we rebin the random fan-beam/cone-beam data via nearest-neighbor, quadrilateral and triangle-based linear interpolati...

Modern CT and micro-CT scanners are rapidly moving from fan-beam toward cone-beam geometry. Half-scan CT algorithms are advantageous in terms of temporal resolution, and widely used in fan-beam and cone-beam geometry. While existing half-scan algorithms for cone-beam CT are in the Feldkamp framework, in this paper we compensate missing data explicitly in the Grangeat framework, and formulate a ...

In this paper an alternative derivation of Katsevich's cone-beam image reconstruction algorithm is presented. The starting point is the classical Tuy's inversion formula. After (i) using the hidden symmetries of the intermediate functions, (ii) handling the redundant data by weighting them, (iii) changing the weighted average into an integral over the source trajectory parameter, and (iv) impos...

The goal is to perform geometric studies on cone-beam CT scanning along a three-dimensional (3D) spiral of variable radius. First, the background for variable radius spiral cone-beam scanning is given in the context of electron-beam CT/micro-CT. Then, necessary and sufficient conditions are proved for existence and uniqueness of PI lines inside the variable radius 3D spiral. These results are n...

The purpose of this work is to extract three-dimensional (3D) motion trajectories of internal implanted and external skin-attached markers from kV cone-beam projections and reduce image artifact from patient motion in cone-beam computed tomography (CBCT) from on-board imager. Cone beam radiographic projections were acquired for a mobile phantom and liver patients with internal implanted and ext...

Introduction: Panoramic view as a routine dental radiograph has an important role in diagnosis of other facial abnormalities accompanied with dento- alveolar structures. In this case presentation, we discuss this subject and also the efficacy of cone-beam computed tomography in localization of foreign body in complex anatomy of nasal cavity.

cemento-ossifying fibroma (cof) is a rare benign fibro-osseous tumor. the radiographic and clini cal features of this lesion are unpredictable and variable. in this report, the patient was a 12-year old girl with a painless swelling which demon strated an opaque lesion with radiolucent zone to involve left posterior portion of the mandible on panoramic radiography. the radiographic manife stati...

background marketing new radiography devices necessitates documenting their absorbed x-ray doses. since the current literature lacks studies on new devices, we assessed the doses of two new devices that had not previously been assessed. objectives the new devices were compared to the promax three dimensional (3d) scanner at two fields of view (fov) in nine critical head and neck tissues and org...

introduction: the purpose of this study was to investigate the root and canal morphology of maxillary first molars with regards to patients’ age and gender with cone-beam computed tomography (cbct). methods and materials: a total of 149 cbct scans from 92 (67.1%) female and 57 (31.3%) male patients with mean age of 40.5 years were evaluated. tooth length, presence of root fusion, number of the ...

introduction: this study sought to assess the effects of amperage (ma) and field of view (fov) on intracanal metal post artifacts and the diagnostic parameters for detection of vertical root fracture (vrf) in teeth with intracanal posts. methods and materials: in this diagnostic study, 80 human single-canal teeth were evaluated by cone-beam computed tomography (cbct). nickel chrome cast posts w...