objective: iqspect is an advanced high-speed spect modality for performing myocardial perfusion imaging (mpi), which uses a multi-focus fan beam collimator with resolution recovery reconstruction. the aim of this study was to compare iqspect compared with conventional spect interms of performance based on standard clinical protocols. in addition, we examined the concordance between conventional...

X-ray luminescence computed tomography (XLCT) is an emerging hybrid imaging modality, which is able to improve the spatial resolution of optical imaging to hundreds of micrometers for deep targets by using superfine X-ray pencil beams. However, due to the low X-ray photon utilization efficiency in a single pinhole collimator based XLCT, it takes a long time to acquire measurement data. Herein, ...

The objective of this work is to quantify the systematic errors introduced by the common assumption of invariant secondary electron spectra with changing field sizes, as relevant to stereotactic radiotherapy and other treatment modes incorporating small beam segments delivered with a linac-based stereotactic unit. The EGSnrc/BEAMnrc Monte Carlo radiation transport code was used to construct a d...

UNLABELLED We present a new rodent SPECT system (U-SPECT-II) that enables molecular imaging of murine organs down to resolutions of less than half a millimeter and high-resolution total-body imaging. METHODS The U-SPECT-II is based on a triangular stationary detector set-up, an XYZ stage that moves the animal during scanning, and interchangeable cylindric collimators (each containing 75 pinho...

UNLABELLED We determined the relative effect of corrections for scatter, depth-dependent collimator response, attenuation, and finite spatial resolution on various image characteristics in cardiac SPECT. METHODS Monte Carlo simulations and real acquisition of a 99mTc cardiac phantom were performed under comparable conditions. Simulated and acquired data were reconstructed using several correc...

Introduction: Treatment efficacy of radiation therapy using Yttrium-90 radionuclide is evaluated by the bremsstrahlung SPECT imaging following radiation therapy. The radioisotopic images have the ability to provide reliable activity map of 90Y distribution. But these images have a low quantitative accuracy in the 90Y bremsstrahlung SPECT imaging, therefore the optimization of...

A prototype gamma-ray scanning system was designed to perform post-irradiation examination measurements of nuclear fuel. The is composed a coaxial high-purity germanium (HPGe) detector, collimator, and mechanical positioning stages that translate the fuel sample across front collimator. This paper documents design process, modeling laboratory characterization performed validate system. done usi...

UNLABELLED The objective of this study, which is related to human brain SPECT, was to increase the sensitivity of a triple-camera SPECT system and reduce statistical noise in reconstructed images using a combination of converging collimators. The reason for combining collimators is to ensure both high sensitivity and sufficient sampling without trading off spatial resolution. METHODS A high-s...