Inkinen Satu Irene, Hippeläinen Eero, Uusitalo Valtteri
HUS Diagnostic Center, Clinical Physiology and Nuclear Medicine, Helsinki University and Helsinki University Hospital, Helsinki, Finland.
Department of Physics, University of Helsinki, Helsinki, Finland.
EJNMMI Res. 2023 Nov 9;13(1):96. doi: 10.1186/s13550-023-01045-7.
Splenic switch-off (SSO) is a marker of adequate adenosine-induced vasodilatation on cardiac magnetic resonance perfusion imaging. We evaluate the feasibility of quantitative assessment of SSO in myocardial positron emission tomography (PET) perfusion imaging using [O]HO.
Thirty patients underwent [O]HO PET perfusion with adenosine stress. Time-activity curves, as averaged standardized uptake values (SUV), were extracted from dynamic PET for spleen and liver. Maximum SUV, stress and rest spleen-to-liver ratio (SLR), and the splenic activity concentration ratio (SAR) were computed. Optimal cut-off values for SSO assessment were estimated from receiver operating characteristics (ROC) curve for maximum SUV and SLR. Also, differences between coronary artery disease, myocardial ischemia, beta-blockers, and diabetes were assessed. Data are presented as median [interquartile range].
In concordance with the SSO phenomenon, both the spleen maximum SUV and SLR were lower in adenosine stress when compared to rest perfusion (8.1 [6.5, 9.2] versus 16.4 [13.4, 19.0], p < 0.001) and (0.81 [0.63, 1.08] versus 1.86 [1.73, 2.06], p < 0.001), respectively. During adenosine stress, the SSO effect was most prominent 40-160 s after radiotracer injection. Cut-off values of 12.6 and 1.57 for maximum SUV and SLR, respectively, were found based on ROC analysis. No differences in SAR, SLR, or SLR were observed in patients with coronary artery disease, myocardial ischemia, or diabetes.
SSO can be quantified from [O]HO PET perfusion and used as a marker for adequate adenosine-induced vasodilatation response. In contrary to other PET perfusion tracers, adenosine-induced SSO is time dependent with [O]HO.
脾关闭（SSO）是心脏磁共振灌注成像中腺苷诱导的血管扩张充分的一个标志物。我们评估了使用[O]HO在心肌正电子发射断层扫描（PET）灌注成像中对SSO进行定量评估的可行性。
30例患者接受了腺苷负荷下的[O]HO PET灌注检查。从动态PET中提取脾脏和肝脏的时间-活性曲线，以平均标准化摄取值（SUV）表示。计算最大SUV、负荷和静息脾肝比（SLR）以及脾活性浓度比（SAR）。根据最大SUV和SLR的受试者操作特征（ROC）曲线估计SSO评估的最佳截断值。此外，还评估了冠状动脉疾病、心肌缺血、β受体阻滞剂和糖尿病之间的差异。数据以中位数[四分位间距]表示。
与SSO现象一致，腺苷负荷时脾脏最大SUV和SLR均低于静息灌注时（分别为8.1[6.5,9.2]对16.4[13.4,19.0]，p＜0.001）和（0.81[0.63,1.08]对1.86[1.73,2.06]，p＜0.001）。在腺苷负荷期间，SSO效应在放射性示踪剂注射后40 - 160秒最为显著。基于ROC分析，发现最大SUV和SLR的截断值分别为12.6和1.57。在冠状动脉疾病、心肌缺血或糖尿病患者中，未观察到SAR、SLR或SLR的差异。
SSO可从[O]HO PET灌注中进行定量，并用作腺苷诱导的血管扩张反应充分的标志物。与其他PET灌注示踪剂相反，腺苷诱导的SSO与[O]HO呈时间依赖性。
