Head movement during a dynamic brain PET/CT imaging results in mismatch between CT and dynamic PET images. It can cause artifacts in CT-based attenuation corrected PET images, thus affecting both the qualitative and quantitative aspects of the dynamic PET images and the derived parametric images. In this study, we developed an automated retrospective image-based movement correction (MC) procedu...

UNLABELLED Integrated PET/MR systems are becoming increasingly popular in clinical and research applications. Quantitative PET reconstruction requires correction for γ-photon attenuations using an attenuation coefficient map (μ map) that is a measure of the electron density. One challenge of PET/MR, in contrast to PET/CT, lies in the accurate computation of μ maps. Unlike CT, MR imaging measure...

In this series we present a quiz about identification of salient and important anatomical landmarks present at a given level on the computed tomography (CT) image. The representative image is followed by further images showing examples of various commonly encountered pathologies that can be seen at this level in clinical practice. Readers are expected to identify highlighted structures in all t...

the purpose of this study was to identify the anatomic structures of the abdominal region of cat throughcomputed tomography (ct) to be used by veterinary radiologists, clinicians and surgeons. the abdominalregion of four cats were scanned twice, with and without using contrast medium in a same position, usinghigh-resolution imaging protocol. slice intervals were 11 mm and were adjusted so that ...

We have developed an algorithm for the rigid-body registration of a 3D CT to a set of C-arm images by matching them to computed cone-beam projections of the CT (DRRs). We precomputed rescaled versions (pyramid) of the CT volume and of the C-arm images. We perform the registration of the CT to the C-arm images starting from their coarsest resolution until we reach some finer resolution that offe...

UNLABELLED The purpose of this study was to compare a routine bone SPECT/CT protocol using CT reconstructed with filtered backprojection (FBP) with an optimized protocol using low-dose CT images reconstructed with adaptive statistical iterative reconstruction (ASiR). METHODS In this prospective study, enrolled patients underwent bone SPECT/CT, with 1 SPECT acquisition followed by 2 randomized...

BACKGROUND Variability in intracoronary computed tomography (CT) number may influence vessel quantification. We confirmed the feasibility of a novel method for measuring vessel diameter and area using coronary CT angiography (CCTA) with an optimized intracoronary CT number, 350 HU. METHODS We performed intravascular ultrasound (IVUS) imaging in 52 patients with significant stenosis detected b...

In previous attempts to identify aquatic vegetation from remotely-sensed images using classification trees (CT), the images used to apply CT models to different times or locations necessarily originated from the same satellite sensor as that from which the original images used in model development came, greatly limiting the application of CT. We have developed an effective normalization method ...