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We appreciate the interest from Dr. van Rij and his colleagues in our work. We respect his long-standing interest in manually shaped corneal transplant incisions. We agree that, all other factors being equal, the optical quality of penetrating keratoplasty improves as the diameter of the graft increases. Presumably this effect occurs because distortion from the sutures, and the incision itself is further from the central optical zone as graft size increases. Our paper did not report and analyze the graft size because the diameter of a zigzag-shaped femtosecond laser incision encompasses a zone of 1 mm. The most common configuration that we employ has an inner diameter of 8.0 mm and an outer diameter of 9.0 mm, but some of our femtosecond incisions had an inner diameter of 7.5 mm and an outer diameter of 8.5 mm, and a few were 7.0/8.0 mm. Donor and host diameters were equal in all but a few early cases. In contrast, the manual trephine incisions predominantly were a mixture of 8.25 mm and 8.75 mm donor grafts into recipient beds with diameters of 8.0 mm and 8.5 mm, respectively. Therefore, a useful analysis of the effect of graft size on the optical outcome is not possible with this data set. As we gain further cases, we do intend to compare the results with different-sized zigzag incisions. Finally, we would point out that most corneal transplantation surgeons will not use a 9.0-mm manual trephine graft, except in unusually large corneas, because the sutures and the incision itself are too close to the limbus. With the different configuration of the zigzag incision, an outer diameter of 9.0 mm is feasible in more eyes, and the outer suture pass does not encroach as much on the limbus. If this is the reason for a better optical result with a zigzag incision by increasing the number of patients who are candidates for this size, we view this as a virtue of the technique. Femtosecond IncisionsOphthalmologyVol. 117Issue 7PreviewWith much interest we read the article, “Comparison of penetrating keratoplasty performed with a femtosecond laser zigzag incision versus conventional blade trephination.”1 However, we wonder if there is any justification for the authors statement that femtosecond laser generated zigzag-shaped incisions result in a more rapid best spectacle corrected visual acuity (BSCVA) and induce less astigmatism in comparison with conventional blade trephination penetrating keratoplasty (PK). Full-Text PDF