宽体能谱CT成像检测肺动脉栓塞的研究

Study on the detection of pulmonary embolism by wide-body energy spectrum CT imaging

目的研究能谱CT碘图联合肺动脉血管成像诊断肺栓塞(PE)的价值,探讨碘图在PE诊断中是否存在附加优势。方法应用宽体能谱CT并加大范围螺距联合前置Asir-V模式扫描,同时得到肺动脉血管图(CTPA)及肺血容量碘灌注图(碘图)2组图像。采用回顾性分析,记录CTPA图中PE的个数和类型(完全闭塞和部分闭塞型),分析碘图上与PE对应的肺组织灌注缺损类型(低灌注、无低灌注),评价CTPA中栓子充盈缺损类型与碘图中肺组织灌注缺损类型的一致性;测量同一患者肺组织低灌注区碘含量(病例组)与正常肺组织的碘含量(对照组),并采用配对t检验比较。结果 34例肺血管成像发现栓子95个,完全闭塞型43个(低灌注41个,无低灌注2个),非完全闭塞型52个(低灌注23个,无低灌注29个),肺动脉栓塞类型与肺灌注缺损类型一致性为一般(Kappa=0.49)。病例组与对照组的碘含量分别为(4.61±4.22)μg/cm^3和(11.65±3.58)μg/cm^3,二者差异有统计学意义(t=-7.68,P<0.05)。结论肺组织低灌注区碘含量低于正常肺组织碘含量,提示肺动脉栓塞的可能,碘图能够发现CTPA观察受限的栓塞区肺动脉栓塞与肺组织灌注缺损不能完全匹配,CTPA与碘图结合补充能提高PE的检出率。

Objective To study the diagnostic value of energy spectrum CT iodination junction combined with arterial angiography in pulmonary embolism(PE),to investigate whether there was an additional advantage of iodogram in the diagnosis of pulmonary embolism.Methods The images of Pulmonary Artery Angiography(CTPA)and Pulmonary Blood Volume Iodine Perfusion Map(Idogram)were obtained by using Wide Physical Energy Spectrum CT combined with pre-Asir-V mode scan.Using retrospective analysis,the number and type of PE in the CTPA we’re recorded(fully occluded and partially occluded),and the types of pulmonary tissue perfusion defects corresponding to PE on the iodine map(low perfusion,no low perfusion)were analyzed.CTPA and Iodine maps were used for consistency analysis.The iodine content in the low-perfusion area of lung tissue(case group)was compared with that in normal lung tissue(control group),and the paired t-test was used.Results In the 34 cases of pulmonary angiography,95 emboli were found,43 cases of complete occlusion(41 cases of hypoperfusion,2 cases of non-hypoperfusion),52 cases of non-complete occlusion(23 cases of hypoperfusion,29 cases of non-hypoperfusion).The consistency between pulmonary embolism type and pulmonary perfusion defect type was general(Kappa value=0.49).The iodine content in the case group and the control group were(4.61±4.22)μg/cm and(11.65±3.58)ug/cm,respectively.There was a significant difference between the two groups(t=-7.68,P<0.05).Conclusion The iodine content in hypoperfusion,area of the lung tissue is lower than that in the normal lung tissue,which suggesting the possibility of pulmonary embolism.Iodide map could find the restricted embolic area of CTPA.Pulmonary embolism is not a perfect match for pulmonary tissue perfusion defect.In conclusion,the combination of CTPA and iodogram can improve the detection rate of PE.