新型冠状病毒感染不同毒株的CT表现演变与临床转归的相关性分析

Correlation Analysis between Dynamic Changes in Computed Tomography Findings and Clinical Outcomes in Cases Infected with Different Strains of Coronavirus Disease 2019

目的:分析、对比新型冠状病毒感染不同毒株胸部CT表现及其演变特点,探讨其与临床转归的相关性。方法:收集、整理内蒙古自治区75例原始株、130例德尔塔(Delta)变异株和562例奥密克戎(Omicron)变异株病例的胸部CT图像,分析、对比不同毒株CT表现及变化规律。结果:Omicron组中的轻型患者比例(499例,88.79%)明显多于原始株组(9例,12.00%)和Delta组(47例,36.15%)。相对于原始株组,Delta组轻型患者发生率较高(47例,36.15%vs.9例,12.00%),重症发生率较低(14例,16.87%vs.19例,28.79%)。96.97%(64例)原始株组病例,93.98%(78例)Delta组病例,98.41%(62例)Omicron组病例初次CT表现以磨玻璃影为主,3组间无统计学差异。在磨玻璃影形态和分布方面,19.05%(12例)Omicron组病例表现为腺泡结节磨玻璃影,明显多于原始株组(3.03%,2例)及Delta组(3.61%,3例),3组病例病灶主要沿胸膜下分布,但Omicron组较原始株组及Delta组沿支气管血管束周围分布比例更高。在伴随征象方面,初次CT中伴随实变和条索比例较低,原始株组、Delta组及Omicron组病例伴随实变比例分别为3.03%(2例),6.02%(5例)和5.00%(1例);伴随条索比例分别为12.12%(8例),15.66%(13例)和20.00%(4例)。原始株组和Delta组病程中病灶影像学表现会出现变化,原始株组39.39%(26例)病例在原磨玻璃影基础上出现实变,53.03%(35例)病例在原磨玻璃影基础上出现条索,明显高于初次CT实变和条索比例;Delta组44.58%(37例)病例在原磨玻璃影基础上出现实变,61.45%(51例)病例在原磨玻璃影基础上出现条索;Omicron组34.38%(11例)病例在原磨玻璃影基础上出现实变,71.88%(23例)病例在原磨玻璃影基础上出现条索,二者同样明显高于初次CT实变和条索比例。原始株组、Delta组和Omicron组病例病灶明显吸收距发病时间中位天数分别为16、16和9 d。结论:新型冠状病毒感染不同毒株胸部CT表现的动态变化,可以反映病变随临床病程的演变规律,对新型冠状病毒感染病程判定和疾病管理具有临床应用价值。

Objective:To analyze and compare chest computed tomography(CT)findings and evolutionary characteristics of different strains of novel corona virus pneumonia and to explore the correlation of CT findings and strain characteristics with clinical outcomes.Methods:Chest CT images of 75 cases of the original strain,130 cases of the Delta variant,and 562 cases of the Omicron variant from the Inner Mongolia Autonomous Region,were collected and sorted.The CT manifestations and their changes for different strains were analyzed and compared.Results:The proportion of patients with mild disease in the Omicron variant group(499 cases,88.79%)was significantly higher than that in the original strain(9 cases,12.00%)and Delta variant groups(47 cases,36.15%).Compared to the original strain group,the Delta variant group showed higher incidences of mild cases%(47 cases,36.15%vs.9 cases,12.00%)and lower incidences of severe cases(14 cases,16.87%vs.19 cases,28.79%).A total of 96.97%(64 cases)of the original strain group,93.98%(78 cases)of the Delta variant group,and 98.41%(62 cases)of the Omicron variant group showed ground-glass opacities,which were the main manifestations on the first CT scan.There was no statistically significant difference among the three groups.In terms of morphology and distribution of ground-glass opacity,12 cases(19.05%)of the Omicron group showed acinular nodule ground-glass opacity,which was significantly higher than that shown by the original strain group(2 cases,3.03%)and the Delta variant group(3 cases,3.61%).The lesions in the three groups were mainly distributed along the subpleural lung regions.However,the Omicron variant group had a higher distribution ratio along the bronchial vascular bundle than the original strain and Delta variant groups.In terms of concomitant signs,concomitant consolidation and cable proportion were significantly lower on the first CT image.The proportions of concurrent consolidation in the original strain,Delta variant,and Omicron variant groups were 3.03%(2 cases),6.02%(5 cases),and 5.00%(1 case),respectively.The proportions of accompanying cables in the original strain,Delta variant,and Omicron variant groups were 12.12%(8 cases),15.66%(13 cases),and 20.00%(4 cases),respectively.The imaging findings of the lesions in the original strain and Delta variant groups changed over the course of the disease.In the original strain group,39.39%(26 cases)had realistic changes based on the original ground-glass opacity and 53.03%(35 cases)had a cord based on the original ground-glass opacity.This proportion was significantly higher than the proportion of consolidation and cord based on the first CT.In the Delta variant group,44.58%(37 cases)of patients showed inflammatory consolidation based on the original ground-glass opacity and 61.45%(51 cases)of patients showed a cord based on the original ground-glass opacity.In the Omicron variant group,34.38%(11 cases)had inflammatory consolidation based on the original ground-glass opacity and 71.88%(23 cases)had cord based on the original ground-glass opacity,both of which were significantly higher than the proportions of primary inflammatory consolidation and cord.The median number of days from apparent absorption to onset in the original strain,Delta variant and Omicron variant groups were 16 days,16 days,and 9 days,respectively.Conclusions:The dynamic changes in chest CT findings of cases infected with different strains of COVID-19 can reflect the evolution of lesions with the clinical course of the disease.This prediction has clinical application value in determining the course of COVID-19 and disease management.