[Simulation of airbag impact on eyes after trabeculectomy by finite element analysis method].
OBJECTIVE
A finite element computer model of the human eye after trabeculectomy was used in an experiment of simulated airbag ocular injury.


METHODS
A half-layer-incised scleral flap was created on the limbus and the strength of its adhesion to the outer sclera was set at 30%, 50% and 100%. The simulations were performed at a workstation using the finite element analysis program PAM CRASH (Nihon ESI, Tokyo, Japan), and the airbag was set to hit the surface of the post-trabeculectomy eye at various velocities in two directions, straight to the corneal center or straight to the scleral flap.


RESULTS
In the case of airbag impact on the corneal center, the scleral flap was unlikely to rupture except when the airbag impact velocity was 40 m/sec. In the case of airbag impact on the scleral flap, at the lowest impact velocity of 20 m/sec, partial scleral flap rupture was likely to occur only at the lower adhesion strength, and scleral laceration extending to the posterior sclera was observed at impact velocities of over 30 m/sec.


CONCLUSIONS
These simulation results suggest that current airbags may induce globe rupture in eyes after trabeculectomy treatment.
Azukisawa
Mikako
M
Department of Ophthalmology, Yokohama City University Medical Center, Japan.
Sato
Takayuki
T
Ito
Yuki
Y
Kamezawa
Hiroshi
H
Nomura
Eiichi
E
Nishide
Tadayuki
T
Kadonosono
Kazuaki
K
Uchio
Eiichi
E
Goto
Satoru
S
D017278:Air Bags / Q000009:adverse effects*; D003198:Computer Simulation; D003315:Cornea; D005131:Eye Injuries / Q000209:etiology*; D006801:Humans; D008953:Models, Anatomic; D012421:Rupture; D012590:Sclera / Q000293:injuries*; D012984:Software; D014130:Trabeculectomy; D014949:Wounds, Nonpenetrating / Q000209:etiology*