Invasive corneal transplants can be avoided for select younger patients with Fuchs’ endothelial dystrophy (FED), and the chance of healing enhanced with the use of a drop developed for glaucoma management.
Sydney ophthalmologist Dr. Gregory Moloney and his colleagues have successfully treated a dozen FED patients ranging from 38 years old to 84 years old with a non-invasive procedure, which involves removing the central 3mm to 4mm of Descemet’s membrane and allowing the cornea to spontaneously heal. Patient selection is critical to the success of this non-invasive procedure, and success is more likely in younger patients, “with good physical reserve” as opposed to “those with poor or diseased peripheral cells,” says Dr. Moloney.
Most recently Dr. Moloney has identified that treating these patients with an existing glaucoma medication may further improve the chance of healing.
Many patients are being booked in for grafts who may not need them and others are getting older graft procedures when we can possibly do better
“We have been following a Japanese study underway to assess the use of a drop for corneal healing – it is based on the same molecule that has already been taken to market for the management of glaucoma. We successfully applied to use the drop as a special access drug to determine its benefit when treating patients with Fuchs’ Dystrophy.”
Dr. Moloney said the opportunity to trial the molecule came when a patient, who had undergone the procedure to remove diseased corneal tissue, showed no sign of spontaneous recovery. “We removed the corneal tissue and two months later it still had not healed. We advised that a transplant would be necessary but in the first instance, we treated her with the drops. Ten days later, her cornea was clear. It’s very early days, but this is looking positive.”
Dr. Moloney will address ophthalmologists on the treatment at a conference in Los Angeles in May and a study is to be published imminently.
Taking the Lead in DMEK
Dr. Moloney is also at the forefront of training Australian surgeons to perform Descemets membrane endothelial keratoplasty (DMEK) on FED patients who are unsuited to non-invasive intervention. The procedure is an evolution of the more routinely performed Descemet’s Stripping Endothelial Keratoplasty (DSEK).
“Rather than transplanting the inner 20 per cent of a donor cornea as in DSEK, we peel off the innermost cellular layer only – taking just 2 per cent of the tissue. Then we inject the donor corneal tissue into the front of the eye, unfold it and squeeze it into place with an air bubble. The surgery can be more challenging but is done through a smaller incision so the eye is much stronger, and visual recovery is faster, typically in two weeks. The chance of achieving 6/6 is 85–90 per cent”.
DMEK leaves a 2mm wound which requires just one stitch. DSEK required surgeons to take 20 per cent of the corneal tissue and leaves a larger wound that requires five stitches.
“This isn’t new surgery, the procedure has been around since 2006, however, there are not as many surgeons doing it with regularity because it is quite a difficult procedure to perform,” said Dr. Moloney.
“What worries me is that the field is evolving so quickly that patients and treating specialists may not be aware of the most innovative procedures currently available for treating Fuchs’ Dystrophy. Some patients are being booked in for grafts who may not need them and others are getting older graft procedures when we can possibly do better. I feel there are some patients I would treat differently now than I would have even two years ago.
“We can provide patients with a micro incision graft which takes just 30–60 minutes in surgery and a day in hospital, or a non-graft surgery, which takes just 15 minutes. As elegant as DMEK is, patients who undergo any transplant surgery require anti-rejection drops forever and will usually need cataract surgery simultaneously or at a later point.
“If we can get them to heal spontaneously, then they won’t need to rely on donor cells – this will remove the risk of rejection and will also free up valuable donor corneas for other procedures.”