Daghini Elena, Primak Andrew N, Chade Alejandro R, Zhu Xiangyang, Ritman Erik L, McCollough Cynthia H, Lerman Lilach O
Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.
Invest Radiol. 2007 May;42(5):274-82. doi: 10.1097/01.rli.0000258086.78179.90.
Myocardial microvascular permeability-surface area product (MPSP) and fractional vascular volume (FVV), indices of endothelial function and microvascular perfusion, can be noninvasively evaluated by electron beam computed tomography (EBCT), but it remains unknown whether comparable assessments can be obtained with 64-slice multidetector CT (CT-64).
We studied 12 pigs with both EBCT and CT-64 in randomized order 1 week apart, before and during IV adenosine infusion. Myocardial attenuation changes in the cardiac wall were assessed after a central-venous injection of iopamidol. Time-attenuation curves were analyzed using both indicator-dilution and Patlak models to calculate MPSP and FVV.
CT-64 and EBCT assessments of basal MPSP obtained by the Patlak method were similar (0.37 +/- 0.03 vs. 0.37 +/- 0.04 mL/min/g), as was its response to adenosine, and correlated significantly (r = 0.87). Patlak FVV was also similar between CT-64 and EBCT at baseline (0.08 +/- 0.02 vs. 0.07 +/- 0.02 mL blood/mL) and during adenosine, and correlated well (r = 0.93). MPSP and FVV estimated by the indicator-dilution method were not significantly correlated.
CT-64 assessments of myocardial MPSP and FVV may not be reliable when using indicator-dilution analysis, likely due to its sensitivity to scan duration. However, CT-64 assessments obtained using the Patlak model are feasible.
心肌微血管通透性-表面积乘积（MPSP）和血管容积分数（FVV）是内皮功能和微血管灌注的指标，可通过电子束计算机断层扫描（EBCT）进行无创评估，但使用64层螺旋CT（CT-64）能否获得类似评估尚不清楚。
我们对12头猪进行了研究，分别在静脉注射腺苷前和注射过程中，以随机顺序相隔1周先后进行EBCT和CT-64检查。中心静脉注射碘帕醇后评估心脏壁的心肌衰减变化。使用指示剂稀释法和Patlak模型分析时间-衰减曲线，以计算MPSP和FVV。
通过Patlak方法获得的CT-64和EBCT对基础MPSP的评估相似（0.37±0.03对0.37±0.04 mL/min/g），其对腺苷的反应也相似，且相关性显著（r = 0.87）。CT-64和EBCT在基线时（0.08±0.02对0.07±0.02 mL血液/mL）以及腺苷注射期间的Patlak FVV也相似，相关性良好（r = 0.93）。通过指示剂稀释法估计的MPSP和FVV无显著相关性。
使用指示剂稀释分析时，CT-64对心肌MPSP和FVV的评估可能不可靠，这可能是由于其对扫描持续时间敏感。然而，使用Patlak模型进行CT-64评估是可行的。
