肺动脉CTA漏诊亚段肺栓塞原因分析

Analysis of missed diagnosis of sub-segmental pulmonary embolism with pulmonary CTA

目的探讨CTPA漏诊亚段肺栓塞(SSPE)的常见原因。方法对临床确诊肺栓塞(PE)的91例患者的影像学资料进行回顾性分析,计算首诊CTPA、复诊CTPA及经查看肺通气/灌注(V/Q)显像结果后复诊CTPA对SSPE的检出率,并与V/Q显像结果进行比较。结果91例PE患者中,3 494支亚段肺动脉显示清楚。肺V/Q显像对SSPE的检出率为19.00%(664/3 494),首诊CTPA的检出率为11.99%(419/3 494),差异有统计学意义(χ~2=65.59,P<0.01);复诊CTPA检出率为13.62%(476/3 494),低于肺V/Q显像(χ~2=37.05,P<0.01);查看肺V/Q显像结果后,复诊CTPA对SSPE的检出率为15.83%(553/3 494),与肺V/Q显像比较差异有统计学意义(χ~2=12.26,P<0.01)。结论CTPA漏诊SSPE的原因主要包括亚段肺动脉观察困难、诊断水平较低和对慢性PE诊断困难。提高阅片医师注意力和针对性,并联合肺V/Q显像,可提高CTPA对SSPE的检出率。

Objective To explore the causes of missed diagnosis of sub-segmental pulmonary embolism（SSPE）with CT pulmonary angiography（CTPA）.Methods Image data of 91 patients with clinically diagnosed pulmonary embolism（PE）were retrospectively analyzed.The detection rate of SSPE was evaluated with three methods,including first diagnosed CTPA,re-diagnosed CTPA and re-diagnosed CTPA after checking the results of pulmonary ventilation/perfusion（V/Q）imaging,and the results were compared with those of V/Q imaging.Results Among 91 patients with PE,3 494 subsegmental pulmonary arteries were clearly displayed with CTPA.The detection rate of pulmonary V/Q imaging for SSPE was 19.00%（664/3 494）,of first diagnosed CTPA was 11.99%（419/3 494,2χ=65.59,P〈0.01）.The detection rate of re-diagnosed CTPA for SSPE was 13.62%（476/3 494）,lower than that of pulmonary V/Q imaging（2χ=37.05,P〈0.01）.The detection rate of re-diagnosed CTPA for SSPE after examining the results of pulmonary V/Q imaging was15.83%（553/3 494）,statistically different with that of lung V/Q imaging（2χ=12.26,P〈0.01）.Conclusion The main causes of missed diagnosis of SSPE of CTPA include difficulties in observing sub-segmental pulmonary arteries,lower diagnostic level and difficulties in diagnosing chronic PE.Improving the attention and pertinence of radiographers,and combining with pulmonary V/Q imaging may improve the detection rate of SSPE.