Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology
“Same-Patient Processing” for multiple cardiac SPECT
studies. 2. Improving quantification repeatability
Guido Germano, PhD a, Paul B Kavanagh, MS a, Terrence D Ruddy, MD b, R Glenn
Wells, PhD b, Yuan Xu, MD a, Daniel S Berman, MD a, Piotr J Slomka, PhD a
a Cedars-Sinai
Medical Center , Los Angeles, CA and b University of Ottawa Heart
Institute, Ottawa, ON, Canada
Copyright American Society of Nuclear Cardiology
Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology
BACKGROUND
1- Differences in quantitative measurements of cardiac
perfusion and function from serial SPECT studies are
meaningful only if quantification is highly repeatable
2- Whenever multiple image datasets for the same patient
exist and need to be analyzed and quantified, one can deal
with the images as a group rather than individually.
3- We previously employed the same-patient processing
(SPP) approach to improve LV segmentation accuracy, and
extend it here to improving the repeatability of quantitative
measurements compared to conventional quantification
Copyright American Society of Nuclear Cardiology
Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology
METHODS
A. Study type:
Repeatability study (automated quantification)
B. Study subjects: 100 patients undergoing back-to-back
rest, stress, gated rest and gated stress SPECT MPI, for
a total of 800 image datasets (8 per patient)
C. Study endpoints:
Repeatability of back-to-back quantitative measurements
D. Study variables:
Ungated volumes, EDV, ESV, LVEF, TPD, Mo/Th TPD
Copyright American Society of Nuclear Cardiology
Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology
RESULTS
1) Overall, SPP resulted in significantly lower differences
between repeated measurements of stress ungated volumes
(1.40±2.76 ml vs. 3.33±5.06 ml), EDVs (1.78±2.78 ml vs.
3.49±5.35 ml), ESVs (1.17±1.96 ml vs. 2.44±3.35 ml) and
LVEFs (-0.45±2.29% vs. -1.16±3.30%) [p<0.05 for all].
2) Additionally, SPP produced better repeatability for stress and
rest ungated volumes (5.4 vs 9.9 and 5.2 vs. 13.1,
respectively), stress TPD (2.6 vs. 3.6), stress and rest EDVs
(5.5 vs. 10.5 and 7.2 vs. 14.7, respectively), stress and rest
ESVs (3.8 vs. 6.6 and 5.3 vs. 10.3, respectively), stress and
rest LVEFs (4.5 vs. 6.5 and 4.7 vs. 8.2, respectively), and rest
total motion deficit (5.6 vs. 9.6)
Copyright American Society of Nuclear Cardiology
Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology
RESULTS
Bland-Altman plots of the differences between quantitative measurements of LVEFs for 100 repeated,
back to back studies. The top and bottom dashed lines in both graphs define the area within which 95%
of the differences fall, and are therefore a visual expression of the repeatability coefficient,
demonstrating better repeatability for SPP
Copyright American Society of Nuclear Cardiology
Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology
CONCLUSIONS
1- Group processing of image datasets belonging to a
patient improves the repeatability of quantitative
measurements of parameters of myocardial perfusion
and function derived from the patient’s SPECT MPI
studies.
2- This application of the same-patient processing
approach is an extension of the “paired processing”
technique already described by our group, and can be
performed in automated fashion through incorporation
in the quantitative algorithm.
Copyright American Society of Nuclear Cardiology