CT scan in the characteristic analysis and injury severity evaluation of pulmonary explosion blast injury

Feng Ling; Wang Hanwei; Zeng Linlan; Li Xuan; Liu Meijin; Duan Zhaoxia; Wang Jianmin; Wang Shunan

doi:10.3969/j.issn.1009-4237.2025.04.002

Abstract：Objective To analyze the imaging characteristics of pulmonary explosion blast injury and to evaluate the predictive value for injury severity by CT scan via a field-based live-explosion goat model.Methods Eighty-seven healthy goats were positioned in standing posture and located in a fan-shape,with their right side facing the explosion source at 3,4,and 5 m from the detonated charge.A single unencased TNT-equivalent explosive col-umn(8 kg)was administered to induce blast injuries.Chest CT scans were conducted within 1 h post-injury using a mobile 16-row CT scanner.General observation and gross pulmonary anatomical examination were performed.Based on their pathological scores,goats were classified into four injury severity groups,respectively mild(n=16),moderate(n=17),severe(n=28),and extremely severe(n=10).Descriptive statistics were used to analyze the CT imaging characteristics.CT semi-quantitative visual scoring and quantitative measurement of injury volume ratio were employed to assess the injury severity.Receiver operating characteristic(ROC)curves were constructed to evaluate the predictive value of CT-related parameters for the severity of pulmonary blast injuries.Results The pri-mary CT findings included pulmonary contusion/laceration(71.2％),pneumothorax(17.2％),atelectasis/consoli-dation(17.2％),and pulmonary bullae(14.9％),with associated extrapulmonary injuries such as thoracic vertebra fractures(31.0％)and subcutaneous emphysema(18.3％).CT semi-quantitative visual scoring showed signifi-cantly different scores among groups:mild(1.3±0.4),moderate(4.8±0.4),severe(8.8±3.5),and extremely severe(13.6±6.0)(P＜0.01 for comparison between any two groups).Quantitative measurement of the injury vol-ume ratio showed the same results:mild(0.04±0.02),moderate(0.25±0.03),severe(0.42±0.13),and ex-tremely severe(0.61±0.17)(P＜0.01 for comparison between any two groups).ROC curve analysis indicated that the AUC to predict blast injury severity using CT semi-quantitative visual scoring was 0.779(95％CI:0.881-0.947,mild vs.moderate),0.841(95％CI:0.687-0.809,moderate vs.severe),and 0.800(95％CI:0.641-0.832,severe vs.extremely severe).The AUC for quantitative measurement of injury volume ratio was 0.873(95％CI:0.882-0.952,mild vs.moderate),0.832(95％CI:0.697-0.832,moderate vs.severe),and 0.850(95％CI:0.656-0.850,severe vs.extremely severe).Conclusion Goat pulmonary blast injuries present with intricate and varied manifes-tations.CT scan is a valuable diagnostic tool,which offers a detailed evaluation of the injury characteristics,and pro-vides significant diagnostic value in assessing the injury severity.