Studies On Findings Of MRI And Pathological Changes Of Soft Tissues Penetrating Wound In The Thigh Of Pigs Shot By Rifle Of 95 Type Made In China

Objective To analyse findings of MRI and pathological changes of soft tissues in the thigh of pigs after shot by rifle,in order to provide theoretical supports for wound management at early stage.Methods 17 adult pigs were used in this experiment after anesthetized by intravenous injection and suspendedly fixed in supine position,the pigs were wounded in 10 meters away with a rifle of 95 type made in China.The wounded limb were undergone 1.5T MRI scans and histological observation after 2h,6h,12h,24h,48h, 9day,and 18day.Results Pathological changes in wounding tissues included four areas:primary bullet track,coagulative necrosis area,fragments area and a part of wavilness area.â‘ primary bullet track was a permanent wound tract caused by bullet penetrating tissues,the findings of MRI manifested hyperintense signal area in T₂ weighted image and hypointense signal area in enhanced T₁ weighted image.â‘¡The thickness of coagulative necrosis area was about 1 to 3 millimeters,which showed hypointense signal phenomenon in both of T₂ weighted image and enhanced T₁ weighted image.â‘¢The fragments area and a part of wavilness area were showed hyperintense signal phenomenon in both of T₂ weight image and enhanced T₁ weighted image.Conclusions Penetrating gunshot wound in soft tissues of hind limb can be divided into four areas:primary bullet track,coagulative necrosis area,fragments area and wavilness area.MRI can clearly show primary bullet track and coagulative necrosis area.Fragments area and a part of wavilness area were hyperintense signal areas on the outside of the primary bullet track,which can be distinguished clearly by pathalogical observation.Coagulative necrosis area caused by hyperthermal bullet penetrating tissues which were burned by high temperature.