Zone of Injury
Zones of Injury are used to classify Open- and Closed-Globe Injuries.
Open- Globe Injury
Zone 1- Cornea and Limbus
Zone 2- Limbus to 5mm posterior into Sclera
Zone 3- Posterior to 5mm from the limbus
Zone 1- External- conjunctiva, sclera and cornea
Zone 2- 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, an a corneo-scleral laceration extending to the rectus muscles would be a Zone 3 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 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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2. Pieramici DJ, Au Eong KG, Sternberg P Jr, Marsh MJ. The prognostic significance of a system for classifying mechanical injuries of the eye (globe) in open-globe injuries. J Trauma. 2003 Apr;54(4):750-4.
3. Yalcin Tök O1, Tok L, Eraslan E, Ozkaya D, Ornek F, Bardak Y.Prognostic factors influencing final visual acuity in open globe injuries. J Trauma. 2011 Dec;71(6):1794-800.
4. Vlasov A, Ryan DS, Ludlow S, Weichel ED, Colyer MH. Causes of combat ocular trauma-related blindness from Operation Iraqi Freedom and Enduring Freedom. J Trauma Acute Care Surg. 2015 Oct;79(4 Suppl 2):S210-5.