OBJECTIVES The aim of this study was to evaluate the influences of reconstruction and attenuation correction on the differences in the radioactivity distributions in (123)I brain SPECT obtained by the hybrid SPECT/CT device. METHODS We used the 3-dimensional (3D) brain phantom, which imitates the precise structure of gray matter, white matter and bone regions. It was filled with (123)I soluti...

Small-animal single-photon emission computed tomography (SPECT) system plays an important role in the field of drug development and investigation of potential drugs in the preclinical phase. The small-animal High-Resolution SPECT (HiReSPECT) scanner has been recently designed and developed based on compact and high-resolution detectors. The detectors are based on a high-resolution parallel hole...

OBJECTIVE Over the past few years, we have performed several brain SPECT studies on patients who have had previous head trauma that required metallic cranioplasty. Transaxial images showed clearly defined photon-deficient areas extending from the brain tissue into the area of the scalp. To investigate the extent and pattern of this type of artifact, SPECT brain phantom studies were performed an...

We have generalized the spectral factor analysis and the factor analysis of dynamic sequences (FADS) in SPECT imaging to a five-dimensional general factor analysis model (5D-GFA), where the five dimensions are the three spatial dimensions, photon energy, and time. The generalized model yields a significant advantage in terms of the ratio of the number of equations to that of unknowns in the fac...

Thresholding is the most widely used organ or tumor segmentation technique used in single photon emission computed tomography (SPECT) and planar imaging for monoclonal antibodies. Selecting the optimal threshold requires a priori knowledge (volumes from CT or magnetic resonance) for the size and contrast level of the organ in question. Failure to select an optimal threshold leads to overestimat...

Background: Photon attenuation as an inevitable physical phenomenon influences on the diagnostic information of SPECT images and results to errors in accuracy of quantitative measurements. This can be corrected via different physical or mathematical approaches. As the correction equation in mathematical approaches is nonlinear, in this study a new method of linearization called ‘Piece Wise Line...

introduction: image quality and accuracy of in vivo activity quantification in spect are affected by collimator penetration and scatter components, especially in high energy imaging. these phenomena highly depend on the collimator characteristic and photon energy. the presence of penetrated and scattered photons from collimator in spect images degrades spatial resolution, contrast and image qua...

BACKGROUND Nuclear medicine imaging of neuroendocrine tumours is performed either by SPECT/CT imaging, using 111In-octreotide or by PET/CT imaging using 68Ga-radiolabelled somatostatin analogs. These imaging techniques will give different image quality and different detection thresholds for tumours, depending on size and activity uptake. The aim was to evaluate the image quality for 111In-SPECT...

UNLABELLED Cerenkov luminescence imaging (CLI) is an emerging new molecular imaging modality that is relatively inexpensive, easy to use, and has high throughput. CLI can image clinically available PET and SPECT probes using optical instrumentation. Cerenkov luminescence endoscopy (CLE) is one of the most intriguing applications that promise potential clinical translation. We developed a protot...

In nuclear medicine, simultaneous dual-isotope imaging is used to determine the distribution of two radiotracers from a single acquisition and for emission/transmission (E/T) imaging in SPECT. However, no general solution to the cross–talk problem caused by scattered and unscattered photons has been found yet and accurate quantification cannot be performed. We describe a general method of spect...