Abstract
Purpose: :
To determine visual acuity and the incidence of ocular damage in a population of veterans with traumatic brain injury (TBI) caused by exposure to combat blast.
Methods: :
This study protocol received Stanford IRB and VA Research Committee approval. 37 consecutive inpatients at a VA Polytrauma Rehabilitation Center who met inclusion criteria underwent visual acuity testing by projected Snellen chart or illuminated cabinet with high-contrast Early Treatment Diabetic Retinopathy (ETDRS) optotypes. A complete eye examination, undilated and dilated, including gonioscopy, was performed. No eyes with penetrating injury were included in the analysis. 10 age and gender-matched controls underwent similar testing.
Results: :
Study patients included 34 men and 3 women, with an age range of 20 to 45 years, and a mean age of 27. Control ages ranged from 19 to 42 years, with a mean age of 31. Seven of 74 eyes (9%) in the TBI group were enucleated or non-sighted. In the 67 sighted eyes, best-corrected visual acuity (BCVA) ranged from 20/10 to 20/200, with a mean acuity of 20/25; 94% were better than 20/40 and 82% were 20/20 or better. All controls had BCVA of 20/20 or better. Incidence and types of eye damage in study eyes included: cornea 7% (superficial scars, embedded debris, rupture of Descemet’s membrane); chamber angle 18% (angle recession, iridodialysis); lens 6% (traumatic anterior or posterior subcapsular cataract); retina 12% (choroidal rupture, retinal hemorrhage, retinal holes, retinal detachment, retinal thinning, macular hole; and optic nerve damage in 3% (optic atrophy, relative afferent pupillary defect). Oculoplastic data was available on 30 study patients: facial or orbital fractures were present in 40%, with facial or lid scarring and lid or brow ptosis in 35%. No ocular or adnexal damage was detected in the control population.
Conclusions: :
Combat blast injury exposes the eye and ocular adnexa to various forces, including primary blast wave, secondary effects of airborne objects, and acceleration/deceleration. Eye injuries seen in our study are consistent with a blunt trauma mechanism. Significant ocular damage may be present in combat veterans exposed to blast, despite good visual acuity and few or no symptoms. A complete eye examination and regular follow-up is recommended in this population.
Keywords: trauma • visual acuity • anterior segment