Comparison of three boundary detector methods for SPECT

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:6795157

Macey, D J; DeNardo, G L; DeNardo, S J

An important objective for accurate attenuation compensation in quantitative SPECT is information on the boundary of the transverse section. The usual ellipse drawn to approximate sections of the brain does not adequately describe the boundary of sections of the body. The objective of this study was to compare the performance of three methods that can define the boundary using scattered photons from a radionuclide source. Three source geometries studied were (i) multiply scattered photons from an internal source in the section (ii) 90/sup 0/ Compton scattered photons from an external collimated source fixed to the gamma camera (iii) Backscattered photons from an external source fixed to the edge of the collimator. For each geometry an appropriate energy window was used for 360/sup 0/ acquisition of 64 images of a thorax phantom. Transverse section images were reconstructed as used for emission SPECT. These section images were smoothed and a threshold used to find the integrity of the boundary. An important advantage of these scatter methods is they can provide, with a single 360/sup 0/ rotation over 10 minutes, individual boundaries of multiple transverse sections that cover a large area of the body. The 90/sup 0/ Compton scatter method using a collimated radionuclide source of Tc-99m was found to give the best definition of the boundary, the backscatter method provided the next best definition. The contour of the final transverse section image was found to be clearly defined and the size of phantom could be determined to 6 mm with the 90/sup 0/ scatter method.

• Research Organization: Univ. of California Davis Medical Center, Sacramento, CA
• OSTI ID: 6795157
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
BASIC INTERACTIONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
BODY AREAS
BRAIN
CENTRAL NERVOUS SYSTEM
COMPARATIVE EVALUATIONS
COMPTON EFFECT
COMPUTERIZED TOMOGRAPHY
COUNTING TECHNIQUES
DIAGNOSTIC TECHNIQUES
ELASTIC SCATTERING
ELECTROMAGNETIC INTERACTIONS
EMISSION COMPUTED TOMOGRAPHY
HEAD
HOURS LIVING RADIOISOTOPES
IMAGE PROCESSING
IMAGES
INTERACTIONS
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
NERVOUS SYSTEM
NUCLEI
ODD-EVEN NUCLEI
ORGANS
PERFORMANCE
PROCESSING
RADIATION SOURCES
RADIOISOTOPES
RADIONUCLIDE KINETICS
SCATTERING
SEQUENTIAL SCANNING
SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY
TECHNETIUM 99
TECHNETIUM ISOTOPES
TOMOGRAPHY
YEARS LIVING RADIOISOTOPES