A Preliminary Study On Virtual Autopsy In Forensic Medical Diagnosis Of Drowning

Objective To explore the feasibility of virtual autopsy using multislice computed tomography in forensic medical diagnosis of drowning,and the application value of the characteristic changes of postmortem lung CT images and blood density changes in the diagnosis of drowning.Methods The drowning corpses were underwent the fiull-body postmortem CT scan before the conventional autopsy.Lung CT image data were used to construct a 3D lung model and relevant parameters of the lung were acquired automatically by medical image processing software.Blood density of the heart and large vein were measured by postmortem CT image data.According to the postmortem CT changes and the difference of the virtual measurement compared with other causes of death,the ability to obtain key information of virtual autopsy in drowning and the value of measurement index were evaluated.Results The postmortem CT images of drowning have an overlap with the control group to some extent,but virtual autopsy can effectively detect pathological changes caused by aspiration of drowning fluid into the body(e.g.respiratory system,circulatory system and digestive system).There were no statistically significant differences in lung volume and average CT values between drowning and non-drowning cases.The relative lung volume ratio increased and the lung CT value distribution curves were different.The mean CT value of blood in drowning decreased,and the CT value of blood in the left atrium,left ventricle and right atrium was signifieantly different from the non-drowning cases.Conclusion Virtual autopsy can be useful as an auxiliary method in the forensic medical diagnosis of drowning.The characteristic changes of lung CT image parameters and the lower blood density can provide more evidence to diagnose drowning.