Eye expert warns 'misconception' among surgeons causing sight loss

Parwez HossainA leading eye expert has warned some patients in the UK may be losing their sight unnecessarily due to a “poor understanding” of the effectiveness of emergency corneal transplantation.

Parwez Hossain, a consultant ophthalmologist at University Hospital Southampton NHS Foundation Trust, said there was a “common misconception” among surgeons that the procedure carried unacceptable risks of rejection and failure.

As a result, patients with severe infection or perforation of the cornea were often offered removal of the affected eye – despite transplant, or graft, survival of at least 40% in even the worst or high-risk cases.

He spoke out following his team’s study, published online by the British Journal of Ophthalmology, which reviewed outcomes from 1,330 emergency corneal graft procedures performed over a six-year period.

They found emergency corneal transplantation was successful in 78% of cases at one year, 66% at two years and 47% at three years. One-year survival for elective – planned – corneal grafts is 90%.

“There is a common misconception among eye surgeons that grafting for severe corneal disease associated with infection and perforation carries unacceptable risks of rejection and failure and, therefore, tend to offer complete removal,” said Mr Hossain, who is based at Southampton General Hospital.

“Our study, which is the largest to investigate outcomes of emergency corneal grafts, should raise awareness that emergency corneal grafting is worthwhile and should be considered at every opportunity to avoid certain sight loss through removal.”

He added: “We found that although there are risks that corneas may fail or reject, over a six-year period even in the worst high-risk case scenarios, the chance of graft survival is at least 40%.

“If we look at the outcome over a shorter time period of just one year, the chance of graft survival rate is much higher and, even if graft failure occurs, vision in many cases still improves.

“From a patient’s perspective, these odds make grafting a much better option than having the eye removed and we need to ensure much better awareness of the positive outcomes achieved through emergency transplantation.”

The eye unit at Southampton General Hospital is one of 12 national eye retrieval centres, which enables the team to store donated eye tissue from patients on the organ donor register for corneal transplantation and some glaucoma surgery.

“The favourable outcomes we have seen in Southampton demonstrate very clearly the importance of having eye retrieval and banking facilities that are able to supply corneal tissue immediately for emergency grafting,” said Mr Hossain, who is also an associate professor of ophthalmology at the University of Southampton.

“This is significant considering that, in many parts of the world, eye banking facilities are rudimentary or non-existent for allowing corneal transplant material to be available in a few hours."

He added: "While this is less of an issue in the UK as we have established an effective eye retrieval network, the challenge here is around changing the perception of corneal transplantation."

Posted on Tuesday 5 December 2017