螺旋CT不同机型胸部平扫对贫血的诊断价值

目的探讨螺旋CT不同机型胸部平扫对贫血的诊断价值。方法通过应用GE HiSpeed NX/I 2层螺旋CT机(2 SCT)和GE LightSpeed VCT 64层螺旋CT机(64 SCT)各进行133例胸部平扫,通过客观上测量计算主动脉腔内CT值、室间隔与房室腔CT值差以及主观上肉眼是否能明确分辨室间隔与房室腔、主动脉腔壁与腔内密度差别,比较和分析贫血组和非贫血组各主、客观指标来探讨螺旋CT不同机型胸部平扫对贫血诊断的价值。结果主动脉腔内CT值与血红蛋白定量值呈明显正相关(r2 sct=0.82,r64 sct=0.90,P=0.00),室间隔与房室腔CT值差与血红蛋白Hb定量值呈显著负相关(r2 sct=-0.71,r64 sct=-0.81,P=0.00)。不同机型贫血组和非贫血对照组主动脉腔内CT测量值、室间隔与房室腔CT值差比较(2 SCT:t值分别为12.17、-11.08,64 SCT:t值分别为13.14、-13.09),差异均有统计学意义(P=0.00);以主观指标房室腔低密度征联合客观指标主动脉腔内CT值≤36 Hu作为胸部CT平扫判定贫血的指标,统计分析全部266例患者结果表明其灵敏度为79.3%,特异度为98.6%,总的符合率为89.8%。结论利用螺旋CT不同机型胸部平扫通过肉眼观察房室腔低密度征联合测量主动脉腔内CT值可以作为较可靠判断是否贫血的依据。

Value of chest CT plain scanning performed on different types of scanners in diagnosing anemia

Objective To investigate the value of chest CT plain scanning performed on different types of scanners in diagnosing anemia.Methods A total of 266 patients were evenly divided into two groups and were performed chest plain scanning on GE HiSpeed NX/I double-slice CT scanner(hereafter was referred to as 2 SCT)and GE LightSpeed VCT 64-slice CT scanner(hereafter is referred to as 64 SCT) respectively.The images were objectively examined by measuring the CT value at the endovascular area of the aorta and comparing the difference of CT values between interventricular septum and atrioventricular cavity,and subjectively examined with naked eyes by differentiating the interventricular septum and the atrioventricular cavity as well as density difference between the walls and the endovascular area of the aorta.The objective and subjective findings of both anemic patients and non-anemic patients were put into comparison and analysis so that the value of chest plain scanning in diagnosing anemia,particularly that in relation to different types of scanners,can be fully assessed.Results The CT value of the endovascular area of the aorta was positively correlated with the quantitative determination of hemoglobin(r2 sct=0.82,r64 sct=0.90,P= 0.00) while the difference of CT values between the interventricular septum and the atrioventricular cavity was negatively correlated with the quantitative determination of hemoglobin(r2 sct=-0.71,r64 sct=-0.81,P=0.00).The comparison between the anemic patients and the non-anemic patients in respect of the CT value at the endovascular area of the aorta and the difference of CT values between the interventricular septum and the atrioventricular cavity presented statistic significance(P=0.00),regardless of the specific type of scanners(t value of 2 SCT were 12.17 and-11.08 respectively;t value of 64 SCT were 13.14 and-13.086 respectively).When such subjective evidence as the low-density sign of the atrioventricular cavity and objective evidence as the CT value of the endovascular area of the aorta being less than 36 Hu were combined together as a diagnostic standard for anemia on the basis of chest CT plain scanning,its response rate reached 79.3% and diagnostic specificity 98.6%,the general consistency being 89.8%.Conclusion On the images of chest plain scanning performed on different types of scanners,the presence of the low-density sign of the atrioventricular cavity in combination with measurement of the CT value of the endovascular area of the aorta is a reliable standard for diagnosing anemia.