A retinal tear is a rip that occurs when the eyeball’s vitreous liquid or “jelly” slides and pulls on the retina. As the eyes undergo the natural aging process, the jelly which fills the inner eye’s back cavity begins to deteriorate and shift. This type of movement makes aging eyes more prone to retinal tears. If a tear occurs along one of the retina’s blood vessels, it may cause a vitreous hemorrhage. This bleeding is sometimes accompanied by a sudden shower of floaters or flashes which can cloud vision.
Whether or not they obscure one’s vision, acute tears put one at risk for vision loss, as they allow fluid to seep under the retina through the tear and can gradually lift the retina off, causing a rhegmatogenous retinal detachment. Because of this risk, optometrists and ophthalmologists will often monitor a person's retinas for tears, which can be detected by dilating the pupils with special eye drops. Once detected, a tear can be sealed to the wall of the eye using lasers or cryotherapy (freezing treatment). These procedures are typically painless and leave a scar at the back of the eye, which seals the retina and prevents fluid from leaking in.
A retinal tear will often go undetected without eye checkups and exams, as its symptoms are painless. Such symptoms include the appearance of, or an increase in, floaters or flashes, which are caused by the degeneration of the vitreous jelly into liquid. Another symptom of this condition is the appearance of a shadow or curtain descending over one eye, which is often to the periphery and grows in size. A sudden decrease in one’s quality of vision may also indicate a tear.
If left untreated, a retinal detachment caused by a tear will result in the retina losing nutrients carried through the blood supply. As a result, the retina can lose its ability to function; in some cases, permanently. Large retinal detachments require surgical treatment, while small detachments can be repaired with a laser in the same manner that retinal tears are sealed.
Individuals who are nearsighted, have had cataract surgery, or have experienced a blow to the head or eye are at an increased risk for developing a retinal tear or detachment. As well, patients who have had a tear in one eye have a one in ten chance of getting a tear in the other. In general, however, retinal detachments are uncommon, and affect roughly one in ten thousand people.