Evaluation of Spatial Uniformity about Resolution and Sensitivity of a 'fixed focusing type SPECT'

Purpose At now, there are many kind of dedicated heart SPECT machine in clinical nuclear medicine. Among those, the fixed focusing type SPECT can make a good quality, quantity image because a detectors of this SPECT arranged forward a special ROI and didn't rotate around of body. So, in this paper, we will evaluate a spatial uniformity about resolution and sensitivity at a same plane of a fixed focusing type SPECT. Materials and Methods We used D-SPECT as a fixed focusing type SPECT and Cario MD as a rotated parallel type SPECT to comparing each other. We injected $^{99m}Tc(14.8MBq/1cc)$ to 10 capillary tube (diameter=1mm), and we set those line sources a tfield of view of each SPECT. And then we acquired SPECT date, we applied are construction by recommended methods. By using two tomography images, we calculated a full width of half maximum as a resolution and total counts as a sensitivity, and we compared a CV (coefficientofvariation) values between two images as a spatial uniformity. Results In case of D-SPECT, a CV of resolution and sensitivity are 7.45%, 12.34%. In case of Cario MD, an CV of resolution and sensitivity are 12.49%, 21.84% Conclusion As a results, CV of resolution and sensitivity of a fixed focusing type SPECT is 67.75%, 77.00% higher than ones of a rotated parallel type SPECT. It means that a fixed focusing type SPECT is more uniformed, because this new SPECT can reduce a motion blur artifact by rotating detector around body, also all of detector that made by semiconductor arrange forward a special FOV like heart.

고정식 초점형 SPECT에 있어, 선예도와 감도의 공간 균일성에 대한 평가

Capillary tube 10개를 $^{99m}Tc$로 채워서 고정식-초점형 SPECT와 회전식-평형 SPECT 장비를 이용하여 선예도와 감도를 평가하였다. 그리고 이 데이터를 이용하여 검출-조사야 내에서의 평균값과 표준편차를 이용하여 균일도를 나타내는 변동계수를 평가하였다. 고정식-초점형 SPECT의 선예도 균일도와 감도 균일도는 회전식-평형 SPECT 에 비해 각각 68%, 110% 높게 평가되었다.