Background: During the past few decades, changes have been observed not only in the prevalence of dental caries, but also in the distribution and pattern of the disease in the population. Most conventional radiographic imaging of teeth underestimates the presence of caries. Cone-beam CT is a new technology which can provide volumetric data of the object, from which cross-sectional images can be...

Using the backprojection filtration (BPF) and filtered backprojection (FBP) approaches, respectively, we prove that with cone-beam CT the interior problem can be exactly solved by analytic continuation. The prior knowledge we assume is that a volume of interest (VOI) in an object to be reconstructed is known in a subregion of the VOI. Our derivations are based on the so-called generalized PI-se...

Computed Tomography (CT) images often suffer from artifacts caused by misaligned scanner geometry of CT system. Calibration and correction must be done before image reconstruction. A method for calibration of misaligned scanner geometry in cone-beam CT with single-circle orbit is proposed. In this method, a four-point phantom is used to estimate a set of parameters that describe the geometry of...

CONCLUSION The saccular duct and endolymphatic sinus run in the bony groove, before reaching the orifice of the vestibular aqueduct. We first clinically visualized this sulciform groove using three-dimensional (3D) cone beam CT images. This strategy can be useful to assess the condition of the saccular duct and endolymphatic sinus concerning the longitudinal flow system of endolymph. OBJECTIV...

PURPOSE This paper introduces a novel autocalibration method for cone-beam-CTs (CBCT) or flat-panel CTs, assuming a perfect rotation. The method is based on ellipse-fitting. Autocalibration refers to accurate recovery of the geometric alignment of a CBCT device from projection images alone, without any manual measurements. METHODS The authors use test objects containing small arbitrarily posi...

Conventionally, surgery and procedural-based radiology are performed on different premises. With advances in imaging technology, the operating room is rapidly being transformed into an intraoperative imaging suite. Diagnostic imaging in conjunction with surgery has great utility and by all accounts has great future potential. During the last decade, cone beam computed tomography (CT) scanners h...

Most of the treatment units, both new and old models, are equipped with a megavoltage portal imager but its use for volumetric imaging is limited. This is mainly due to the poor image quality produced by the high-energy treatment beam (> 6MV). A linac at our center is equipped with a prototype 2.5 MV imaging beam. This study evaluates the feasibility of low-dose megavoltage cone-beam imaging wi...

Introduction: Cone beam computed tomography (CBCT) was introduced and became more common based on its low cost, fast image procedure rate and low radiation dose compared to CT. This imaging modality improved diagnostic and treatment-planning procedures by providing three-dimensional information with greatly reduced level of radiation dose compared to 2D dental imaging modalitie...