【摘要】 目的分析非对称基于自旋回波的回波平面成像(ASE)序列定量测量犬可控性高碳酸血症前后氧摄取分数(OEF)的变化。方法选择杂种犬5只,在麻醉后的基础状态下吸入95%O2和5%CO2混合气体5min后进行头部ASE序列和灌注加权成像序列扫描。分别在OEF图、静脉脑血容积(vCBV)图和脑血容积(CBV)图测量双侧大脑半球的OEF值、vCBV值和CBV值,并比较吸入混合气体前、后OEF值、vCBV值及CBV值的差异。结果犬吸入混合气体前、后平均OEF值、vCBV值分别为0.31±0.03、0.30±0.02和0.27±0.18、0.17±0.11,差异有统计学意义(Z=-2.43、-3.82,P均<0.05);吸入混合气体前、后平均CBV值为(695.32±200.71)ml/(100ml·min)、(782.54±301.85)ml/(100ml·mn),差异有统计学意义(Z=-3.48,P<0.01)。结论在犬可控性高碳酸血症时,ASE序列能够反映脑组织OEF值的变化。更多还原

【Abstract】 Objective To assess cerebral OEF change induced by hypercapnia in canines by using ASE.Methods Five canines were enrolled.All canines were anaesthetized and imaged under normocapnia and hypercapnic conditions with ASE and PWI sequences.Experimental hypercapnia was induced by changing the gas mixture from room air(normocapnia)to 5% CO2 and 95% O2(hypercapnia)while the canine inhaled the gas mixture through a nasal oxygen catheter connected with an oxygen bag.Quantitative oxygen extraction fraction(OEF)values,venous cerebral blood volume(vCBV)values and cerebral blood volume(CBV)values in the brain parenchyma were obtained and compared between normocapnia and hypercapnia.Results The mean OEF values and vCBV values were 0.31±0.03,0.30±0.02 and 0.27±0.18,0.17±0.11 under normocapnia and hypercapnia respectively(Z=-2.43,-3.82,both P<0.05).The mean CBV value were(695.32±200.71)ml/(100 ml·min)and(782.54±301.85)ml/(100ml·min)under normocapnia and hypercapnia respectively(Z=-3.48,P<0.01).Conclusion The ASE sequence can reliably detect the OEF change induced by hypercapnia of dog.更多还原