The DAVID is a transparent, multi-wire transmission-style detector that attaches to a linear accelerator (linac) collimator for use as an in vivo detector. Currently, the normal method for using the DAVID is to measure a signal at the time of phantom-based pretreatment verification and use that signal as a baseline to compare with in vivo measurements for subsequent treatment fractions. The dev...

External SDD systems can also replace Si(Li) detectors on existing microscopes and offer many of the advantages of the in-situ SDD systems. Since the SDDs do not operate at liquid nitrogen temperatures, the insulation gaps in the nosepiece/collimator assemblies can be reduced or eliminated. Also, the detector window and the associated support frame are no longer used. This means that the detect...

Using a model and a simulation method, the problems caused by miniaturization of goniometers are discussed from the viewpoint of the stress error caused by systematic errors including the mis-setting of the specimen and the misalignments of the collimator and detector of the Ψ assembly X-ray stress analyzer with a position sensitive detector. As a concluion, it was found that stress errors incr...

In this paper, we will report the development of an ultrahigh resolution MR-compatible SPECT system that can be operated inside a pre-existing clinical MR scanner for simultaneous dual-modality imaging of small animals. This system is constructed with 40 small-pixel CdTe detector modules assembled in a fully stationary ring SPECT geometry. We have experimentally demonstrated that this system is...

EGS is a very popular Monte Carlo code, used in the simulation of Nuclear Medicine devices. Simulation techniques are particularly effective to optimize collimator configuration and camera design in Single Photon Emission studies. With the EGS code, users must define the geometry where particles are transported. This can be both a very hard task and a source of inefficiency, especially in the c...

background: obtaining high quality images in single photon emission tomography (spect) device  is the most important goal in nuclear medicine. because if image quality is low, the possibility of making a mistake in diagnosing and treating the patient will rise. studying effective factors in spatial resolution of imaging systems is thus deemed to be vital. one of the most important factors in sp...

We evaluation basic characteristics of a compact type semiconductor gamma camera (eZ-SCOPE AN) of Cadmium Zinc Telluride (CdZnTe). This new compact gamma camera has 256 semiconductors representing the same number of pixels. Each semiconductor is 2 mm square and is located in 16 lines and rows on the surface of the detector. The specific performance characteristics were evaluated in the study re...

We have developed a prototype imaging system that can perform simultaneous x-ray transmission CT and SPECT phantom studies. This system employs a 23-element high-purity-germanium detector array. The detector array is coupled to a collimator with septa angled toward the focal spot of an x-ray tube. During image acquisition, the x-ray fan beam and the detector array move synchronously along an ar...

Background: Obtaining high quality images in Single Photon Emission Tomography (SPECT) device  is the most important goal in nuclear medicine. Because if image quality is low, the possibility of making a mistake in diagnosing and treating the patient will rise. Studying effective factors in spatial resolution of imaging systems is thus deemed to be vital. One of the most important factors in S...

This study aims at the experimental determination of the detector-specific 1D lateral dose response function K(x) and of its associated rotational symmetric counterpart K(r) for a set of high-resolution detectors presently used in narrow-beam photon dosimetry. A combination of slit-beam, radiochromic film, and deconvolution techniques served to accomplish this task for four detectors with diame...