An improved method for correction of partial volume effects (PVE) in brain SPECT is proposed. It is fully three-dimensional, does not require particular patient positioning, and works with scans only partially covering the brain. The location of functionally inactive brain regions (primarily cerebrospinal fluid) is extracted from high-resolution MRI. An automatic 3D registration algorithm then ...

BACKGROUND AND PURPOSE The ability to identify patients at increased risk for stroke from cerebral hemodynamic ischemia may help guide treatment planning. We tested the correlation between regional cerebrovascular reserve (rCVR) on acetazolamide-challenged single-photon emission CT (SPECT) brain scans and intracranial collateral pathways as well as extra- or intracranial (EC-IC) arterial stenos...

Thanks to its ability to yield functionally rather than anatomicallybased information, the SPECT imagery technique has become a great help in the diagnostic of cerebrovascular diseases. Nevertheless, SPECT images are very noisy and consequently their interpretation is difficult. In order to facilitate this visualization, we propose an unsupervised 3D Markovian model allowing to segment a brain ...

UNLABELLED We report the extended application of an automated computer technique for three-dimensional spatial registration of SPECT and PET studies. METHODS The technique iteratively reslices a misaligned data set until the sum of the absolute differences (SAD) from a reference data set is minimized. The registration accuracy was assessed in Hoffman brain phantom studies collected with known...

Objective: Reconstruction parameters must be optimized to approach the improved spatial resolution that is theoretically possible from modern SPECT imaging devices. One important reconstruction consideration is proper selection of the back-projection filter parameters. The aim of this study was to determine which Butterworth filter optimized image resolution for brain SPECT scans. Methods: Ten ...

Most nuclear medicine clinicians use only visual assessment when interpreting regional cerebral blood flow (rCBF) from single-photon emission computed tomography (SPECT) images in clinical practice. The aims of this study were to develop a new, easy to use, automated method for quantification of rCBF-SPECT and to create normal values by using the method on a normal population. We developed a 3-...

AIMS To determine the effect of diabetes mellitus (DM) on regional cerebral blood flow (rCBF) patterns in patients with Alzheimer's disease (AD). METHODS We investigated the initial rCBF of 71 AD patients (36 without DM and 35 with DM) and the final rCBF of 23 AD patients (12 without DM and 11 with DM) after an average of 32 months. Single-photon emission computed tomography (SPECT) data were...

We present a 21-year-old woman with tumefactive multiple sclerosis (MS) that exhibited a rapidly progressive course. There were multiple tumor-mimicking contrast-enhance lesions with surrounding edema and mass effect on magnetic resonance imaging. Both early and delayed brain single photon emission computed tomography (SPECT) with N-isopropyl-p-[123I]-iodoamphetamine demonstrated increased accu...

Sixteen patients with primary brain tumours were examined on average eight years after treatment with surgery or whole brain irradiation using standard clinical assessment, CT, a neuropsychological test battery, and single photon emission CT (SPECT) with 99mTc-exametazime. Seventeen lesions were discovered on inspection of SPECT images, 11 with x-ray CT. Quantitative assessment of tracer uptake...

INTRODUCTION A physical 3-dimensional phantom that simulates PET/SPECT images of static regional cerebral blood flow in grey matter with a realistic head contour has been developed. This study examined the feasibility of using this phantom for evaluating PET/SPECT images. METHODS The phantom was constructed using a transparent, hydrophobic photo-curable polymer with a laser-modelling techniqu...