PURPOSE To measure the sensitivity of deformable image registration to image noise. Deformable image registration can be used to map organ contours and other treatment planning data from one CT to another. These CT studies can be acquired with either conventional fan-beam CT systems or more novel cone-beam CT techniques. However, cone-beam CT images can have higher noise levels than fan-beam CT...

CBCT versus conventional CT Cone beam computed tomography (CBCT), which is also referred to as cone beam volumetric imaging (CBVI) and cone beam volumetric tomography (CBVT), is an extraoral radiographic method of producing three-dimensional digital radiographic information (Patel et al, 2009a; Patel, 2009; Miles, 2008; McNamara, Kapila, 2006; Horner, Drage, Brettle, 2008; Patel et al, 2007). I...

Coherent backscattering (CBS) is a beautiful physical phenomenon that takes place in a highly scattering medium, which has potential application in noninvasive optical property measurement. The current model that explains the CBS cone shape, however, assumes the incoming beam diameter is infinitely large compared to the transport length. In this paper, we evaluate the effect of a finite scalar ...

OBJECTIVE To assess the diagnostic potential of 2 different cone-beam computerized tomography (CT) units and compare this with intraoral digital and conventional film in the detection of chemically created periapical lesions. STUDY DESIGN Periapical lesions were created chemically in 27 intact roots of 23 teeth (6 incisors, 4 canines, 6 premolars, and 7 molars). Cone-beam CT and digital and f...

PURPOSE The study was aimed to compare online 6 degree-of-freedom image registrations of TrueBeam cone-beam computed tomography and BrainLab ExacTrac X-ray imaging systems for intracranial radiosurgery. METHODS Phantom and patient studies were performed on a Varian TrueBeam STx linear accelerator (version 2.5), which is integrated with a BrainLab ExacTrac imaging system (version 6.1.1). The p...

OBJECTIVE Phantoms with simulating mandibular trabecular bone structure fabricated using micro-stereolithography were applied for a quantitative evaluation of cone-beam computed tomography (CT) images. MATERIALS AND METHODS Phantoms with a three-dimensional lattice, in which a square pillar was set at 0.10, 0.20, 0.30 and 0.40 mm at the edge, spaced at 0.60 mm, were made of an acrylic resin u...

C-arms are well suited for obtaining cone-beam projections intra-operatively. Due to the compact size of the detector used, the data are usually truncated within the field of view. As a result, direct application of a standard cone-beam reconstruction algorithm gives rise to undesirable artifacts and incorrect values in the reconstructed image volume. When prior information such as a pre-operat...

internal inflammatory root resorption (iirr) is a rare condition of the root canal and if it is left untreated it may lead to destruction of the surrounding dental hard tissues. odontoclasts are responsible for this situation which can potentially perforate the root. many initiating factors have been mentioned for iirr, almost all causing chronic inflammation in the vital pulp. iirr is usually ...

conclusions ultrasound is recommended as the first choice when fb is located within the superficial soft tissues with no bone around it. in case of penetration of fb into deeper tissues or beneath bone, ct or cbct are recommended. otherwise, considering lower dose, cbct is preferred over ct. we can use mri if the fb is not ferromagnetic. however, ct is the first choice in emergency situations b...

use of rotary nickel-titanium (niti) instruments for endodontic preparation has introduced a new era in endodontic practice, but this issue has undergone dramatic modifications in order to achieve improved shaping abilities. cone-beam computed tomography (cbct) has made it possible to accurately evaluate geometrical changes following canal preparation. this study was carried out to compare cana...