Introduction: Metallic artifacts due to pacemaker/ implantable cardioverter defibrillator (ICD) leads in CT images can produce artifactual uptake in cardiac SPECT/CT images. The aim of this study was to determine the influence of the metallic artifacts due to pacemaker and ICD leads on myocardial SPECT/CT imaging. Methods: The study included 9 patients wh...

Introduction: Quality assurance in Computed tomography (CT) centers in developing countries are largely hindered by the unavailability of CT phantoms. The development of a local CT phantom for the measurement of organ radiation absorbed dose is therefore requisite. Material and Methods: Local CT phantoms were designed to meet the standard criteria of 32 cm diameter for body, 16 cm diameter for...

Objective- The aim of this study was preparing detailed anatomic images of the thoracic cavity of the southern white-breasted hedgehog using the non-invasive computed tomography (CT) technique.Design- Descriptive study.Animals- Five southern white-breasted hedgehog (Erinaceus concolor) which is a species native to the Middle East, Anatolia, Transcaucasia, and Iran. Since some people...

Background: In CT systems, the machine utilizes a bowtie filter to shape the X-ray beam and remove lower energy photons. The shape of this bowtie filter is complicated and its geometry is often not available in detail. These renders the CT dose index (CTDI) to have different values in measurement versus Monte Carlo simulation studies and other analytical calculations especially in dosimetry of ...

Introduction: Nowadays, magnetic resonance imaging (MRI) in combination with computed-tomography (CT) is increasingly being used in radiation therapy planning. MR and CT images are applied to determine the target volume and calculate dose distribution, respectively. Since the use of these two imaging modalities causes registration uncertainty and increases department w...

background: the aim of this study was to evaluate the reduction in excision cavity volume (ecv) during the whole breast radiotherapy (wbrt). the delineating of reduced cavity volume on secondary ct (computed tomography) might decrease the field size of boost plan. materials and methods: twenty patients were treated having breast conservative surgery. at first, primary ct simulation (ct-1) was d...

The present exploratory mixed methods study aimedto develop a scale for assessing critical thinking (CT) ability of Iranian EFL learners. The study wasconducted in three phases. In phase one, the features of CT components were examined in the writingsof 120 participants. A holistic and an analytic scale were developed based on their performance in exploiting the components of CT and the fea...