Pre Descemets Endothelial Keratoplasty is a partial thickness corneal transplant. The diseased endothelial cells are removed from the patient’s eye and selectively replaced with a new layer of endothelial cells which are taken from the donated eye. The endothelial cells are the healthy cells lining the back of the cornea which pump fluid from the cornea to prevent the cornea swelling. The normal endothelial count is 2000 – 3000 cells/mm2. When the cells decrease in number < 500 cells/mm2, corneal decompensation occurs, clarity of the cornea reduces and eventually the vision becomes cloudy.
The surgery is usually performed under local anaesthesia. Through a small corneal incision (opening), the endothelium is removed from the patient’s eye and a disc of donor endothelium is inserted in the patient’s eye which is placed in position with the help of an air bubble. A few stitches may be taken which will be removed 3-4 weeks after the surgery. The patient needs to lie down flat for a few hours post surgery for proper attachment of the graft. The air bubble usually gets absorbed in 48 hours but may take longer.
The donor eye is genetically different from the patient’s body, due to which the patient’s body tries to fight against it. This is called corneal graft rejection.
The symptoms are : Redness, Sensitivity to light, Vision drop, Pain (RSVP). Along with sticky discharge and foreign body sensation.
Report to your Ophthalmologist as soon as possible if any of the above symptoms show up post surgery.
When the corneal rejection has not been promptly treated or does not respond to anti- rejection medication, graft failure has occurred. It can be managed by replacing the graft.
Written by: Dr. Preethi Naveen – Chairman, Education Committee
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