药代动力学开放式双室模型在直肠癌CT灌注成像中的应用

目的 研究药代动力学开放式双室模型在直肠癌CT灌注成像中的应用。方法 对36例由结肠镜及术后病理证实的直肠癌患者术前行CT平扫，选定靶平面后，行CT灌注扫描。根据CT灌注参数，绘制靶平面肿瘤组织ROI及靶血管（肿瘤供血动脉）的时间-密度曲线。根据药代动力学开放式双室模型计算公式推导肿瘤内血浆隔室容积百分比（f_P）、组织间隙隔室容积百分比（f_I）、表观血流量（F）及表面通透性（PS）。结果 36例直肠癌的f_P值为（17.3±7.4）%，f_I值为（34.3±11.6）%，F值为（141.0±47.8）ml/（min ·100 g），PS值为（43.2±18.8）ml/（min ·100 g）。结论 药代动力学开放式双室模型为定量评价直肠肿瘤组织内微循环的特性提供了新的思路，具有潜在的临床应用价值。

Application of open two-compartment model of pharmacokinetics in rectal cancer CT perfusion imaging

Objective To explore the application of open two-compartment model of pharmacokinetics in rectal cancer CT perfusion imaging. Methods Thirty-six patients with pathologically confirmed rectal adenocarcinoma underwent CT scan preoperative. After seletcting target plane, the CT perfusion imaging was performed. According to CT perfusion parameters, the time-density curve was obtained of target plane ROI and target vessels (tumor feeding artery). Relative volume fraction of the plasma compartment (f_P), relative volume fraction of the interstitial compartment (f_I), apparent plasma flow (F) and permeability-surface area product (PS) were calculated by open two-compartment model of pharmacokinetics. Results The values of f_P, f_I, F and PS were (17.3±7.4)%, (34.3±11.6)%, (141.0±47.8)ml/(min ·100 g) and (43.2±18.8)ml/(min ·100 g), respectively. Conclusion Open two-compartment model of pharmacokinetics provides a new method in evaluating microvascularity of rectal cancers with CT, and had potential clinical applications.