Safe size of corneal graft with less chances of failure is ?

Ans. is 'a' i.e., 7.5 mm Correlation of corneal graft diameter and chances of graft failure Increased corneal graft size has been repoed in some studies to be a significant risk factore for graft rejection. Other studies refute this and point to smaller graft size as more likely to be rejected. There is increased risk of rejection and endothelial failure in small grafts with recipient size < 7mm and also increased risk of rejection in large grafts with graft size > 8.5 mm. Thus the corneal graft with graft diameter between 7 and 8.5 mm has more chances of survival.