新規全身用半導体SPECT装置と心臓専用半導体SPECT装置における心筋SPECT画像の比較

Comparison of myocardial perfusion SPECT imaging between a new whole-body CZT-SPECT camera and a dedicated cardiac CZT-SPECT camera

これまで半世紀にわたって広く使用されてきたSPECT装置は，アンガー型と呼ばれるヨウ化ナトリウム結晶を用いた検出器を搭載した装置であったが，2000年代に入り半導体検出器を搭載した心臓専用のSPECT装置が登場し，2010年以降日本にも導入され徐々に普及してきた。この装置は「心臓核医学においてこの50年間で一番重要な進歩である」といわれるほどの革命をもたらし，導入施設は今もなお増え続けている。

Purpose：Dedicated cardiac CZT-SPECT cameras demonstrate superior performances compared with Anger-SPECT cameras. We assessed the feasibility and availability of a new whole-body CZT-SPECT camera ‘VERITON’ compared with a dedicated cardiac CZT-SPECT camera ‘D-SPECT’ for myocardial perfusion SPECT imaging in same cases. Methods：We included cases who consented to undergo SPECT imaging with ²⁰¹Tl at treadmill or vasodilator stress using both cameras between November 2019 and April 2020. Stress image was taken with both cameras for the same time first, and rest image taken four hours later. We compared SSS, SRS and SDS of acquired images by visual analysis, and ％Ischemia, EDV, ESV and EF by quantitative analysis between both cameras. Results：Eight cases（five males, mean 70.5 years of age）were included finally. There were no significant differences in SSS, SRS and SDS by visual analysis between both cameras. ％Ischemia and EDV were not significantly different by quantitative analysis though EF was significantly different. The feature of images of VERITON was lower perfusion at inferior wall or uniform perfusion compared with D-SPECT.

Conclusions：Our study suggested the feasibility of myocardial perfusion SPECT imaging using a new whole-body CZT-SPECT camera ‘VERITON’ with understanding of the features, compared with a dedicated cardiac CZT-SPECT camera ‘D-SPECT’.