There are limitations however. If enough hemorrhage occurred from the tear to obscure the doctor's view, treatment may not be possible right away. The hemorrhage will also prevent penetration of the laser light to the tear. This is similar to the failure of your auto the headlights to penetrate fog. If the blood will not clear, there are multiple tears, their location is difficult to reach, the tear is very large or the retina around the tear has become elevated quickly i.e. retinal detachment, another approach may be needed and this will be discussed in the section on retinal detachments .
Some people are more vulnerable than others.
As noted above, the nearsighted and those people who have had cataract surgery are a little more at risk. Men are a little more at risk than women, perhaps due to increased risk of injury, although most retinal detachments are not due to trauma. The tugging on the retina by the vitreous usually pulls free in most people causing one or two floaters as described or perhaps no symptoms at all. In some people the fibers in the vitreous are attached strongly enough to the retina the separation of the vitreous may tear it. When the retina is stimulated by the tugging it has only one thing it can do-report light to the brain.