Zone of Injury
Zones of Injury are used to classify open- and closed-Globe Injuries.
Zone 1- Cornea and Limbus
Zone 2- Limbus to 5mm posterior into sclera
Zone 3- Posterior to 5mm from the limbus
Zone 1- External anterior segment including conjunctiva, sclera and cornea
Zone 2- Internal anterior segment including the lens, zonules and pars plicata
Zone 3- Posterior segment including vitreous, retina, optic nerve, choroid and ciliary body.
Zone of Injury Documentation
When classifying an injury, one always uses the highest zone injury. For example, a corneo-scleral laceration extending to the rectus muscles would be a Zone 3 open-globe injury not a Zone 1, 2, and 3 injury. Again, in a closed globe injury with a conjunctival abrasion, lens dislocation and a retinal detachment, this would be a Zone 3 closed-globe injury, not a Zone 1, 2 and 3 injury.
Multiple studies have shown that Zone 2 and Zone 3 injuries compared to Zone 1 injuries have a worse visual prognosis.
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