Patients will have to undergo new tests

A packaging error is thought to be to blame for the fault, which can cause cloudy vision.

Two specific brands are involved. It is thought they have been used on 80,500 people, although only a small number are likely to experience problems.

One hospital in Gloucestershire alone is contacting 1,800 people who underwent surgery.

The affected brands are:

• Bausch and Lomb Hydroview H60M intraocular lens fitted between 1997 and 2001

• Ophthalmic Innovations International Inc Aqua-sense fitted between December 1999 and 2000.

The Medicines and Healthcare products Regulatory Agency issued device alerts on Monday to all UK hospitals explaining the problems.

So far, 19 hospitals have reported problems with small numbers of patients to the MHRA.

Each hospital will decide how to tackle the issue and whether or not to contact patients.

Blurred vision

It was found that a chemical used in the packaging could interact with the lens to give cloudiness and poor vision.

Gloucestershire Hospitals NHS Trust says 22 people have already complained of blurred vision.

It has written to 1,800 people offering them check-up appointments with a specialist.

The trust says patients with problems caused by the implant will be seen very quickly. The 22 who have come forward have either had corrective surgery, or are scheduled for an operation.

It claims the fault should not affect waiting times for operations.

Dr Guy Routh, the trust's medical director, said: "We felt that because of the number of people coming forward with cloudy lens implants, we should contact all patients who had cataract operations between September 2000 and April 2001 offering them an appointment.

"We felt that offering everyone an appointment was the right thing to do, to reassure patients."

Kent Woods, MHRA chief executive, said: "As with any surgical procedure, a small number of patients experience complications after cataract surgery, but MHRA is aware of reports of clouding of some types of lens, several years after surgery.

"One hospital is reviewing all its patients that could possibly be affected to get a better idea of the extent of this problem.

"Meanwhile, we have asked hospitals to consider contacting their patients to see if they need an appointment with a specialist."

Lens implants (also known as intra-ocular lenses) are used in cataract surgery to replace the patient's own lens.

In a statement, the MHRA said the majority of patients with Aqua-sense or Hydroview lens implants would not have a lens that clouds over and so will not need to be reviewed by their surgeon.

If a patient does have a lens that goes cloudy, this will be obvious because their sight will become worse than it was just after they had their surgery.

Patients with these lenses who do not have problems with their vision do not need to do anything at the moment.

However, if they develop problems in the future, they should contact their eye surgeon or hospital at that time.

Manufacturer's view

Andrew Webb, of Bausch and Lomb UK, said only 0.2% of patients fitted with the Hydroview lens contained in the faulty packaging had subsequently developed problems with clouded vision.

He said: "We are working in close partnership with the Gloucestershire Hospitals NHS Trust to help them provide patients who may have been fitted with these lenses with all the necessary information and advice."