TOY laser pens could cause lasting damage to children’s eyes, a leading Bolton ophthalmologist has warned.

Laser novelty pens — often purchased abroad — can cause significant damage to vision if used incorrectly, according to a new study.

Simon Kelly, a consultant opthalmologist at the Royal Bolton Hospital, says misuse of “extremely powerful” laser pens can result in mild to severe long-term vision damage.

The study, by the Royal College of Ophthalmologists, was based on eye patients in Sheffield aged between eight and 15.

Mr Kelly, who co-wrote the study, said he had come across similar cases of eye damage caused by laser pens in Bolton.

Mr Kelly said: “I am very concerned about these pens and what the study draws attention to is the misuse of these laser pointers.

“They should not be in the hands of children and parents should be aware of the dangers.

“It is quite difficult to know what the different strengths are, particularly with the laser pens purchased outside of Europe.

“The appeal for youngsters with these pens is that they’re a novelty and are naturally intriguing. The problem is when they’re used as a toy and pointed directly at the eye.

“They can burn the retina and in the most severe cases they may leave a scar or damage the back of the retina. This can reduce vision and cause a permanent impairment.”

Laser pens purchased in countries such as China or Thailand are often up to 70 times more powerful than regulated pens available in the UK.

It is not illegal, but Mr Kelly argues: “If I was to take one of these pens out and shine it into somebody’s eye, it could be seen as assaulting someone.”

One mum, aged 54, from Halliwell, who did not want to be named, said her 14-year-old son suffered potentially permanent damage from a laser pen purchased in Thailand.

She said: “We’re not sure how my son damaged his right eye but he did come back from holiday with a laser pen.

“Not long after he started complaining about a silver blob on the back of his eye. Parents don’t realise how dangerous these lasers pens are.”