Any time there is a penetrating wound to the cornea, the iris is often injured as it is directly beneath the cornea in the eye. The injury can be a direct laceration to the cornea or the iris can prolapse through a laceration in the cornea. Blunt trauma can also impact the iris. The most common injuries to the iris include tears in the sphincter and dialysis of the root of the iris. You can also get iridoschisis and atrophy of the iris. Most iris injuries also result in a traumatic hyphema.
Iris injuries are important because, when they are injured, they result in a distorted, nonreactive pupil and photophobia because the iris doesn’t close down when exposed to light. If the pupil is contracted permanently, there can be a loss of full vision. The idea behind treating an iris injury is to preserve as much of the tissue of the iris as possible and to restore its normal architecture.