Mechanism and Emergency Management of Blast Eye/Orbital Injuries

Sabri T Shuker

Disclosures

Expert Rev Ophthalmol. 2008;3(2):229-246. 

In This Article

Blast Mechanism & NOE & Ocular Injuries

Nasal–orbital–ethmoidal skeleton injuries due to primary blast wave dynamic impact with sufficient uniformed force leads to a total collapse of the tensile strength gained by architectural features of the orbit and ocular region. When this shell skeleton is compressed to small, thin bone fragments, the convexity of the wave creates a concave depression of previously convex facial skeleton in the implosion phase. This is followed by an explosion phase, which brings it back to somewhat the original shape. The implosion and miniature re-explosion of compressed air sinuses leads to crush injury to this region. The primary blast effect shock wave propagates through the different medium of eye globe and related orbital anatomical tissues causing contusion and concussion to organs and tissue in the region. It may also affect brain tissue by transverse wave propagation through orbital roof, damaging the cribriform plate, olfactory plate, and cause frontal and ethmoidal sinuses fractures. This is similar to a crushed eggshell by blast wave impacts to middle-third facial skeleton; this could be anterior or unilateral to this region (Shuker) Figure 2.[29,30]

Physical effect of the spherical blast wave front smashing the middle-third skeleton.

The secondary blast effect plays a major role in ocular injuries from projectiles such as shrapnel, pebbles, falling glass and sand particles with environmental debris in and outside the area of detonation. Particle impact on the sclera/corneal membrane creates processes such as stress mechanical contact. The inertial and stress concentration effects in these situations often produce partial or complete corneal/sclera contusion and laceration, which diminishes ocular wall resistance. The primary blast wave impacts on a weakened eye wall, facilitating a rupturing of the eyeball through the mechanism of spalling and pressure differentials of different eye/orbital medium. Scleral/corneal abrasion or partial or almost full thickness laceration that weakens the eye elastic collagen wall increases the possibility to rupture by lower primary blast wave stress impact.[31,32] The primary blast wave front impacts to the orbital region due to spalling and to pressure differentials and the eye globe sustained stress of high-pressure force may be enough to rupture the eyeball.[106]

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....