Presentation
Young patient at the ER with right frontal wound and altered state of consciousness. Referring gun shot.
Patient Data
Small cortical hemorrhagic contusion at the right frontal lobe, associated skin wound and subcutaneous hematoma.
No skull fracture.
Oval shaped well defined foreign body at the subcutaneous plane, hyperdense on the brain window with lack of streak artefacts, hypodense on the bone window (378 UH).
Metallic vs non-metallic projectile
Comparison between Metal projectile from another patient (images on the left) and plastic Bullet from this case (on the right), at bone and brain CT window respectively.
Streak artifacts and very high density values >3000UH help to differentiate metal ones, characteristics not seen on this plastic bullet, useful findings when the weapon it's unknown.
Case Discussion
Plastic bullets or rubber bullets are considered non-lethal, but they can cause penetrating and non-penetrating injuries according to their ballistic coefficient at the moment of impact. They can carry significant kinetic energy, and this energy can cause- as in this case, soft tissue wounds and brain tissue lesion- hemorrhagic contusion. It is important to differentiate them from metallic bullets because their wounds are non-sterile and they need to be removed to avoid local infection.