Magnetic resonance imaging and pathology of soft tissues penetrating wounds in pig thigh shot by domestic-made 95 type rifle / 解放军医学杂志

ABSTRACT

Objective To analyze the magnetic resonance imaging(MRI) appearance and pathological changes of pig thigh of soft tissues after been shot by rifle,so as to offer a theoretical foundation for wound management in early stage of gunshot injuries.Methods Seventeen adult pigs were intravenously anesthetized and suspended in supine position,the pigs were shot in 10 meters away by domestic-made rifle of 95 type.The wound limb were undergone 1.5T MRI scans and histological observation at 2h,6h,12h,24h,48h,9day,and 18day after shot injury.Results The wounded tissues included four areas of different pathological changesprimary ballistic cavity,coagulative necrosis area,tissue disruption area and tissue distortion area.The thickness of coagulative necrosis area was about 1 to 3 millimeters,which showed double-hypointense signal phenomenon in both T2 weighted image and enhanced T1 weighted image.The tissue disruption area and part of tissue distortion area showed double-hyperintense signal phenomenon in both T2 weight image and enhanced T1 weighted image.Conclusion Penetrating gunshot wound in soft tissues of hind limb can be divided into four areasprimary ballistic cavity,coagulative necrosis area,tissue disruption area and tissue distortion area.MRI can clearly show primary ballistic cavity and coagulative necrosis area.Tissue disruption area and tissue distortion area are hyperintense signal areas on the outside of the primary ballistic cavity,which can be distinguished clearly by pathalogical observation,but tissue disruption area and part of tissue distortion area are undistinguishable by MRI.