The gun consists of:
(1) a chamber to place a blank charge filled with gunpowder
(2) a piston and bolt, which is driven through the cranium by explosion of the gunpowder charge over a distance of 6 to 8 cm
(3) a spring to automatically withdraw the bolt after the gas discharge
Mechanism of injury:
(1) dispersion of bone fragments
(2) blast effect, with increased intracranial pressure from gas discharge
(3) penetration of the bolt
Discharge of the gun against head may be associated with:
(1) suicide attempt
(2) homicide
(3) accidental ("playing around")
The location of the discharge determines the likelihood of death. Discharge at the base the skull or temple is more likely to be fatal than discharge over the frontal bone.
Hitting a major artery can result in intracranial or extracranial hemorrhage.
Different powder charges can be used. The greater the charge the more extensive the damage.
Consciousness during the early postinjury period is associated with a better prognosis. Deep coma is a poor prognostic sign.
If the person survives, then long-term disability depends on what cerebral structures have been damaged. Permanent hemiplegia is common.
