Gun trauma to head poses risk of long-term visual impairment
Survivors of gun trauma to the head are 44 percent more likely to sustain long-term visual damage following injury, according to a study.
Researchers looked at 915 victims of gun trauma to the head and identified 27 (3.0 percent) who had ocular injuries including orbital fracture, ruptured globe, foreign body or optic nerve injury. Records were available for 22 patients. Gun types included all firearms and air guns.
Of the 22 patients, 18 survived. There were eight survivors (44 percent) who sustained long-term visual damage, defined as permanent loss of vision in at least one eye to the level of counting fingers or worse.
Location of injury (p=0.243), type of gun used (p=0.296) and cause of gun trauma (p=0.348) all failed to predict visual loss outcome. The Glasgow Coma Scale eye response score at admission to the hospital also did not predict visual loss outcome (p=0.793).
The current findings may be less relevant for victims of gun trauma with ocular involvement who retain their globe, as the seven of the eight patients with long-term vision loss underwent an evisceration or enucleation.
According to researchers, gun trauma to the head results in significant ocular damage through a variety of mechanisms, including direct injury to the visual system by projectiles or blast effects, or indirect damage via traumatic brain injury. Ophthalmologists should be able to manage these difficult cases and counsel patients regarding their visual prognosis.
Further research is needed to identify the most important factors predicting long-term visual damage.