Journal of Nuclear Medicine Technology, Vol 27, Issue 2 123-126, Copyright © 1999 by Society of Nuclear Medicine
An assessment of the sensitivity of the Cedars-Sinai quantitative gated SPECT software to changes in the reconstruction of the short-axis slices
N Fredericks, P Baxter, E McKay and R Smart
Department of Nuclear Medicine, St. George Hospital, Kogarah, Australia.
OBJECTIVE: This study assessed whether variations in count density,
reconstruction filtering parameters and the short-axis orientation selected
for reconstructions of myocardial short-axis slices significantly
influenced the left ventricular ejection fraction (LVEF) calculated from a
gated myocardial perfusion SPECT study. METHODS: The Cedars-Sinai
quantitative gated SPECT software package was used to estimate the LVEF
from gated 99mTc-sestamibi and 201TI gated SPECT studies in 20 patients.
Oblique slices were reconstructed 12 times for each study, independently
varying the filter cutoff and the orientation of the short axis each time.
RESULTS: There were no clinically significant changes in the LVEF over the
range of cutoff frequencies or orientation for either the 201TI or
99mTc-sestamibi studies. There was excellent agreement between the LVEF
calculated from the 201TI and 99mTc-sestamibi studies on the same patients
using the default filter (mean difference = 0.25% points). CONCLUSIONS: The
Cedars-Sinai quantitative gated SPECT software package for parallel-hole
collimators can be used with confidence to obtain an LVEF, and is not
sensitive to variations in count density, filtering parameters or
short-axis orientation.
