Download Quantitative Gated SPECT

segmental scores with value 1 for both stress and rest scans are adjusted to 0, and segmental rest
scores with values higher then stress scores are assigned the stress score values. Reversibility
scores are defined as the difference between Stress and Rest scores.
17.3 Shape Index
This parameter defines 3D left ventricular (LV) geometry derived from LV contours in end systolic
and end diastolic phases. Shape index is defined as the ratio between the maximum dimension of
the LV in all short-axis planes and the length of the midventricular long axis.
Abidov A, Slomka P, Hayes SW, Aboul-Enein F, Kang X, Yoda S, Nishina H, Yang L, Cohen I, Thomson L, Friedman JD,
Germano G, Berman DS. Left Ventricular Shape Index Assessed By Gated Myocardial Perfusion SPECT: A New
Scintigraphic Marker Of Congestive Heart Failure. SNM 2004 Abstract, No 500, page 176P
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A
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A
For each short axis plane in the end-diastolic (ED) image series, maximum dimension (A) of the
LV is found from the 3D contours derived by the QGS algorithm, using the endocardial surface as
the boundary. Global short-axis end-diastolic dimension (AED) is found as a maximum for all ED
short axis slices. The short-axis slice and direction of AED is then used to calculate the maximum
short-axis end-systolic dimension (AES) in the end-systolic image series, by measuring the
distance between the endocardial points in the identical location (slice and direction) where AED
was found.
B
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