Patient motion in thallium-201 myocardial SPECT imaging. An easily identified frequent source of artifactual defect
Because Tl-201 SPECT requires that patients remain in an awkward position for a prolonged time, patient motion is a potentially serious source of artifactual defects on tomographic reconstructions. Thus, a simple method was developed for detection and correction of motion from SPECT images using a Co-57 point source placed on the lower anterior chest, an area remaining in the camera's field of view throughout imaging. In the absence of motion, this point source inscribes a straight line on planar summation of the 32 projections over 180 degrees. Movement is detected by deviation from this line. The number of pixels of motion is used to shift images so that the resultant images of the point source are linear. The method of motion detection and correction was tested in 48 consecutive patients undergoing Tl-201 SPECT. The corrected and uncorrected images were reconstructed and long and short axis tomographic cuts were quantitatively analyzed using circumferential profiles of maximal counts with comparison to the lower limits of normal. Motion was detected in eight of 48 patients (17%). The amount of motion was 2 pixels in three patients and 1 pixel in five patients. Quantitative defect extent was less after correction in seven of eight patients, with a mean decrease of 71% in patients with 2 pixel motion and 44% in patients with 1 pixel motion. This corresponded with a definite reduction in the size of the tomographic defect by visual analysis, and closer resemblance to quantitatively analyzed planar images performed either before or after tomography in the same patient.
- Research Organization:
- Cedars-Sinai Medical Center, Los Angeles, CA (USA)
- OSTI ID:
- 7187273
- Journal Information:
- Clin. Nucl. Med.; (United States), Vol. 13:5
- Country of Publication:
- United States
- Language:
- English
Similar Records
Quantitative analysis of the tomographic thallium-201 myocardial bullseye display: critical role of correcting for patient motion
Orbit-related variation in spatial resolution as a source of artifactual defects in thallium-201 SPECT
Related Subjects
HEART
SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY
IMAGES
MOTION
ERRORS
COBALT 57
OPTIMIZATION
PATIENTS
POSITIONING
THALLIUM 201
BETA DECAY RADIOISOTOPES
BODY
CARDIOVASCULAR SYSTEM
COBALT ISOTOPES
COMPUTERIZED TOMOGRAPHY
DAYS LIVING RADIOISOTOPES
DIAGNOSTIC TECHNIQUES
ELECTRON CAPTURE RADIOISOTOPES
EMISSION COMPUTED TOMOGRAPHY
HEAVY NUCLEI
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANS
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
THALLIUM ISOTOPES
TOMOGRAPHY
550601* - Medicine- Unsealed Radionuclides in Diagnostics