320排螺旋CT对主动脉夹层者肾血流灌注的研究

目的探讨主动脉夹层(AD)患者的肾脏CT灌注特点,分析夹层各种影响因素与肾灌注值的关系,评价其临床价值。方法对46例主动脉夹层患者术前进行双肾血流灌注检查(注射流率5 ml/s,总量40 ml,370 mg I/ml),同时行胸腹部CTA检查,测量双肾血流量参数值(BF),并观察主动脉夹层各种解剖形态学指标。结果显示破口位于左锁骨下动脉以远(36例)或升主动脉(7例)。A型夹层的BF值低于B型患者(P0.05),内膜破口数量不同BF值无显著差异(P0.05)。假腔无血栓的AD患者BF值显著高于假腔有血栓的患者(P0.05)。肾动脉开口于真腔、假腔和骑跨组BF值有差异(P0.05)。真腔组BF值最高,而骑跨组最低。内膜破口大小与BF值相关,随着破口大小增加BF值增大(P0.05)。肾动脉起源于真腔、假腔无血栓化及破口数目的增多易得到较高的BF值。结论 320排CT灌注成像可用于评价整个肾脏血流动力学特征,破口大小、数目及位置、假腔血栓形成及肾动脉起源对主动脉夹层患者肾血流灌注均有影响。灌注成像有助于术前的准备。

320-row CT perfusion imaging of kidneys in aortic dissection

Objective To investigate the relationship between renal perfusion and various factors of aortic dissection using multidetector CT.Methods 46 patients with aortic dissection underwent pre-operative 320-row CT perfusion imaging of the kidneys with 40 ml of intravenous iodinated contrast at 370 mg/ml and 5 ml/s.Thoracic and abdominal CT angiography was also performed.The bilateral renal blood flow (BF) was measured and various CT imaging signs of aortic dissection were observed.Results The entry points of the dissection were far from the left subclavian artery (36/46) or were in the ascending aorta (7/46).The renal BF of patients with type A was significantly lower (P＜0.05) than that of type B dissections.There was no significant change in the renal BF with the number of intimal tears (P＞0.05).The renal BF was significantly higher in false lumen without thrombus (P＜0.05) than that with thrombus.The renal BF among the true lumen,false lumen,and overriding groups also differed significantly (P＜0.05) with highest BF in the true lumen group and lowest BF in the overriding group.Increasing size and number of entry intimal tears,false lumen without thrombus,and origin of renal artery from the true lumen were significantly associated with higher renal BF (P＜0.05).Conclusion 320-row CT perfusion imaging can be used to evaluate hemodynamic features of the kidneys.The size,number and position of intimal tears,false lumen thrombosis,and origin of renal artery can influence renal perfusion of patients with aortic dissection.