A new technique which allows jewellery to be inserted into the eye could be dangerous and should be avoided, say British ophthalmic experts.
Studs are inserted under local anaesthetic
The procedure to insert a tiny platinum jewel stud into the eyeball has been performed in The Netherlands.
The technique is harmless and carries no side effects, say its Dutch pioneers.
But UK eye specialists disagree and say it could be dangerous and may cause scarring and bleeding.
Specially developed jewellery is inserted into the eye's mucous membrane under a local anaesthetic eye drop, at a cost of about £330.
It involves inserting a 3.5mm-wide piece of platinum - that the eye will accept - and includes designs such as a glittering half-moon or heart.
The procedure has been carried out on six women and one man by a team from the Institute for Innovative Ocular Surgery in Rotterdam (NIIOC).
The piece of jewellery is inserted in the conjunctiva - the
mucous membrane lining the inner surface of the eyelids and front of the eyeball - in sterile conditions using an operating microscope in a procedure taking about 15 minutes.
NIIOC director Gerrit Melles said: "Without doing any harm to the eye we can implant a jewel in the conjunctiva.
"So far we have not seen any side effects or complications and we don't expect any in the future.
"In my view it is a little more subtle than (body) piercing.
"It is a bit of a fun thing and a very personal thing for people."
British eye experts disagree and fear cosmetic invasive surgery could harm the eye.
John Dart, a consultant ophthalmic surgeon at Moorfields Eye Hospital in London, said this type of surgery could irritate the eye.
"The stud is quite likely to move around and migrate because the tissue in the conjunctiva is quite loose," he said.
"Any movement is likely to cause inflammation. If it moves, there will be some scar tissue and you could get some bleeding."
An Eyecare Trust spokesman said anything inserted beneath the cornea is "potentially dangerous".
He added: "Jewellery is fine, but not in the eye.
"To carry out surgery to improve eyesight is one thing, but we are opposed to it purely for cosmetic enhancement."
The NIIOC, which develops new ocular surgical techniques in corneal, cataract and retinal surgery, has patented the jewellery and the surgical procedure.
The institute, which carries out the procedure in
co-operation with an eye clinic near the city of Utrecht, said it had a waiting list for people who wanted the implant.