Implanted lenses - legal action considered.

An artist whose vision deteriorated after lens replacement surgery is one of dozens of people considering legal action against manufacturer, Oculentis.

Denise Di Battista, a landscape painter, claims she has "blind patches" in her right eye with the new lens.

She is among what may be as many as 800 UK patients, a very small proportion of the total, experiencing "opacification", a cloudiness in their vision caused by calcium deposits, from a particular implanted lens from European manufacturer, Oculentis.

Opacification, a known risk of lens replacement surgery, can happen with any intraocular lens and can have multiple causes.

Denise Di Battista, who depends on painting for her living, had a routine eye operation in 2010 to replace both of her natural lenses but a few years later, the vision in her right eye unexpectedly started to deteriorate.

She says: "If I was looking through my right eye, I would think I was almost blind. It affects my painting and that depresses me terribly."

Ms Di Battista, who says she was devastated when she learned the problem was possibly caused by an issue with the lens, does not have a problem with black-and-white contrast but she does with colours, tones and low light.

She says: "I was very shocked. When I came out of the consulting room, my daughter was waiting for me and she said I looked white."

Her experience was followed by reports that a small number of patients who had received a particular lens were experiencing opacification.

Oculentis investigated and identified the problem as possibly being the result of an interaction between phosphate crystals used in the hydration process and silicone residues on the lens.

The company says there is evidence some people may be predisposed to this problem or that certain medication can be a factor.

Oculentis has advised providers to return affected batches of the type of lens Denise Di Battista had been given. There is no suggestion that any Oculentis lenses currently available are affected.

Leading eye surgeon Sheraz Daya, who has tried to help patients like Ms Di Battista, said: "A percentage of lenses have deposits of calcium on the surface that become evident only five to seven years later, when they accumulate enough to obscure their vision.

"It is understandably devastating for patients who thought they were done and dusted for life and didn't anticipate an issue with the lens."

Oculentis says the only way to correct the problem is to replace the lenses and has paid for surgeons, including Sheraz Daya, to do this. So far about half of those affected have had their lenses replaced.

Around half a million people have cataract surgery each year, making it the most commonly performed operation in the UK.

There are an estimated 800 UK cases from the affected batches of Oculentis lenses, which have led to problems with opacification, a very small proportion of the total.

In a statement, Oculentis said: "We regret if any patients have experienced complications following the implant of one of our lenses.

"Opacification, or clouding of the lens, is a known risk of lens eye surgery and can be caused by a number of factors interacting, which are not necessarily attributable to the lens itself.

"The incidence rate is extremely low. It can be effectively remedied through lens exchange surgery, which is a safe and well-established procedure.

"Anyone experiencing any vision impairment should consult their surgeon or clinic who will be able to diagnose the cause and recommend an appropriate course of action, otherwise there is no need for any concern."