|
KMID : 0357520210440060645
|
|
Journal of Radiological Science and Technology
2021 Volume.44 No. 6 p.645 ~ p.653
|
|
|
Variation on Estimated Values of Radioactivity Concentration according to the Change of the Acquisition Time of SPECT/CT
|
|
Kim Ji-Hyeon
Park Hoon-Hee
Lee Joo-Young
|
|
|
Abstract
|
|
|
|
With the recent development of precision medicine(Theranostics), interest and utilization of the quantitative function of SPECT/CT are increasing. This study aims to investigate the effect on the radioactivity concentration estimate by the increase or decrease in the total time of SPECT/CT imaging conditions. A standard image was obtained by the conditions of a total acquisition time of 600 sec(10 sec/f × 120 frames) by diluting 99mTc 91.76 MBq in a cylindrical phantom filled with sterile water, and a comparative image was obtained by increasing the total acquisition time by -90%, -75%, -50%, -25%, +50%, +100%. The CNR, radioactive concentration estimate(cps/ml), and the variation rate(%) of the recovery coefficient(RC) were analyzed by measuring the overall coefficient of interest in each image. The results[CNR, Radiation Concentration, RC] by the change in the number of projections for each increase or decrease rate(-90%, -75%, -50%, -25%, +50%, +100%) of total acquisition time are as follows. [-89.5%, +3.90%, 1.04] at ?90%, [-77.9%, +2.71%, 1.03] at ?75%, [-55.6%, +1.85%, 1.02] at ?50%, [-33.6%, +1.37%, 1.01] at ?25%, [-33.7%, +0.71%, 1.01] at +50%, [+93.2%, +0.32%, 1.00] at +100%. and also The results[CNR, Radiation Concentration, RC] by the acquisition time change for each increase or decrease rate(-90%, -75%, -50%, -25%, +50%, +100%) of total acquisition time are as follows. [-89.3%, -3.55%, 0.96] at ?90%, [-73.4%, -0.17%, 1.00] at ?75%, [-49.6%, -0.34%, 1.00] at ?50%, [-24.9%, 0.03%, 1.00] at ?25%, [+49.3%, -0.04%, 1.00] at +50%, [+99.0%, +0.11%, 1.00] at +100%. Image quality(CNR) showed a pattern of change in proportion to the increase or decrease in the total acquisition time of SPECT/CT, but the result at quantitative evaluation showed a change of less than 5% in all experimental conditions, maintaining quantitative accuracy(RC less than 0.05) without much influence.
|
|
|
KEYWORD
|
|
|
Theranostics, SPECT, Quantitative Functions, Aquisition Time, Radioactivity Concentration
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|