Unusual Refractive Errors Induced by Interchanging Trephines During Penetrating Keratoplasty

In this article, a small series of cases is presented in which large refractive errors inadvertently result from a change in the brands of trephine used for corneal transplantations. From these experiences, it is evident that the corneal surgeon should be very cautious if he chooses to interchange various brands and types of trephines.