BACKGROUND AND PURPOSE To date, no systematic evaluation of image quality has been performed on the 256-section multidetector CT scanner for extracranial carotid evaluations. We evaluated image quality, patient dose, and examination time and compared these parameters with a 64-section multidetector CT. MATERIALS AND METHODS We reviewed extracranial CTA scans obtained on a 256-detector CT scan...

Combined PET/CT scanners now play a major role in medicine for in vivo imaging in oncology, cardiology, neurology, and psychiatry. As the performance of a scanner depends not only on the scintillating material but also on the scanner design, with regards to the advent of newer scanners, there is a need to optimize acquisition protocols as well as to compare scanner performances on an objective ...

Telecentric optical computed tomography (optical-CT) is a state-of-the-art method for visualizing and quantifying 3-dimensional dose distributions in radiochromic dosimeters. In this work a prototype telecentric system (DFOS-Duke Fresnel Optical-CT Scanner) is evaluated which incorporates two substantial design changes: the use of Fresnel lenses (reducing lens costs from $10-30K t0 $1-3K) and t...

the advent of dual-modality pet/ct imaging has revolutionized the practice of clinical oncology, cardiology and neurology by improving lesions localization and the possibility of accurate quantitative analysis. in addition, the use of ct images for ct-based attenuation correction (ctac) allows to decrease the overall scanning time and to create a noise-free attenuation map (μmap). the near simu...

This paper presents the first successful demonstration of all-optical MEMS (microelectromechanical system) fiber endoscope for OCT (optical coherence tomography) measurement. A MEMS optical scanner for spatial light modulation has been assembled in the endoscope probe head (φ 6mm) with optical components and a photovoltaic cell. Actuation energy for the MEMS scanner is optically supplied by usi...

Introduction: In 2000, the UNSCEAR reported that CT constitutes 5% of all the medical x-ray  examinations and it contributes 34% of the resultant collective dose worldwide. Children are more  sensitive to the ionizing radiations than adults. So, routine quality control tests are expected to be  carried out periodically on the CT scanners. The aim of this research was to estimate the effective  ...

UNLABELLED Multimodality PET/CT of the liver can be performed with an integrated (hybrid) PET/CT scanner or with software fusion of dedicated PET and CT. Accurate anatomic correlation and good image quality of both modalities are important prerequisites, regardless of the applied method. Registration accuracy is influenced by breathing motion differences on PET and CT, which may also have impac...

Introduction: In radiotherapy treatment planning system (TPS), basic input is the data from computed tomography (CT) scan, which takes into account the effect of inhomogeneities in dose calculations. Measurement of CT numbers may be affected by scanner-specific parameters. Therefore, it is important to verify the effect of different CT scanning protocols on Hounsfield unit (HU) and its impact o...

The recent introduction of combined positron emission tomography (PET)/computed tomography (CT) scanners is having a far-reaching effect on the field of medical imaging by bringing functional imaging to the forefront in radiology, oncology and other specialties. The PET/CT scanner is an evolution in technology combining two well-developed imaging modalities: anatomical imaging with CT and funct...

Introduction: The use of a simple tissue analog material in the fabrication of medical computed tomography (CT) imaging phantoms has great potential to help researchers. The purpose of the present study is to develop new gel tissue-equivalent materials and determine whether their CT numbers and relative electron densities vary in CT images obtained by scans at different energie...