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Two corneal suction trephination systems currently in use are the Barron-Hessburg and the Hanna trephine. This study assessed the outcome of patients who received penetrating keratoplasty using these two systems. One hundred twenty-four eyes (62 with the Hanna system, 62 with the Barron-Hessburg system) from 98 patients undergoing penetrating keratoplasty were evaluated retrospectively. Best corrected spectacle acuity and corneal astigmatism were assessed 6 and 12 months after surgery. No significant difference was noted between the groups 6 months after surgery. At 12 months, a significant improvement in spectacle acuity was present with 55% of the Hanna group having visual acuity of 20/40 or better compared with 33% of the Barron-Hessburg group (p < 0.005). This difference was greater if eyes having the best visual prognoses were separately evaluated: 74% of the Hanna group had 20/40 vision or better compared with 41% of the Barron-Hessburg group (p < 0.005). In eyes having a good visual prognosis, a significant improvement in visual acuity was present, with 33% of the Hanna group improving nine or more lines compared with 9% of the Barron-Hessburg group (p < 0.05). Postoperative keratometric and refractive astigmatism were not different at 6 or 12 months. We found that visual recovery at 1 year is better using the Hanna system, especially in eyes with good visual prognoses.