A new study has warned that cosmetic procedures to remove wrinkles can lead to permanent blindness.

The researchers say that by injecting fillers into people’s foreheads there is a possibility, in rare cases, of causing irreversible damage to the eye.

The scientists from USA state that it is usually safe to inject fat or collagen into the skin to smooth out wrinkles. However, they point to the fact that the Food and Drug Administration (FDA) only supports the use of fillers in the middle part of the face.

Despite these substances not officially being approved for use near the eyes, they are commonly used to remove or improve the appearance of wrinkles around the eye.

In a recent study it was reported that three people have been blinded by the procedure.

A woman in her forties had her forehead injected with collagen to smooth out the wrinkles. After the procedure, she was unable to see out of her right eye.

A man in his thirties had a similar problem with the same procedure. He lost some sight in his left eye after some of the blood supply to his retina had been compromised.

Finally a woman in her sixties had filler injected into her hairline; the complications left her with a severe loss of vision.

The researchers state that this can occur if the filler accidentally seeps into blood vessels and travels into the eye’s artery, causing the blood supply to the eye to be blocked.

The researchers state that although these procedures do not normally cause side-effects other than temporary bruising and swelling, there have been reports of patients suffering a stroke and even dying after the treatment.

The scientists state that all doctors should fully explain the risk to their patients before carrying out the procedure.