Thousands of people who have undergone cataract operations are being contacted by the NHS regarding faulty lenses.
Some patients may require surgery
Plymouth Hospitals NHS Trust has sent out 2,297 letters to people who underwent the operation at the Plymouth Royal Eye Infirmary.
The manufacturers Bausch and Lomb issued a national recall after reports that some lenses became cloudy.
Estimates are that about 200 of 5,000 patients given the lens over a three year period might need further surgery.
The difference between the number 5,000 and the number of patients written to is because some patients had more than one lens and some of the patients fitted with the lens have since passed away.
The problem developed because of the way the lens was packaged, affecting a small batch.
Royal Eye Infirmary clinical director Tim Freegard said: "We would like to reassure patients that there are no immediate harmful issues with the lens and any problems that develop with people's vision will do so slowly and gradually.
"There are many reasons why someone's vision may get worse, only a small number of these may be connected with the faulty lens.
"But if you receive a letter and are experiencing glare or misty vision, please do get in touch."
The affected patients were all given the lens between December 1997 and May 2001.
In October, 700 people contacted a helpline opened by the trust.