Original Article

The impact of donor cornea keratometry on post-keratoplasty keratometry - Original Article

  • Umut Duygu Uzunel

Received Date: 05.06.2009 Accepted Date: 14.08.2009 Turk J Ophthalmol 2009;39(6):469-476

Purpose: To investigate the significance of keratometric measurements of donor corneas before the excision as a predictive factor for post-keratoplasty keratometries. Methods: In this prospective observational study, donor corneas that will be used in penetrating keratoplasty surgeries were measured with portable autokeratometer before the excision. These measurements were compared with the measurements of graft keratometries following penetrating keratoplasty. All surgeries were performed with 0,25 mm larger donor button and all interrupted sutures. Corneal sutures were removed at the period ranging from postoperative month 13 to 15 months. Results: Mean keratometric values and standard deviatons was 43.24 ± 1.46 diopters for donor corneas and 39,89 ± 3,08; 40,35 ± 3,34; 41,18 ± 3,13; 44,31 ± 3,22 and 44,34 ± 3,33 diopters at postoperative month 1, 6, 12, 18 and 24 for post-keratoplasty corneas, respectively. Statistically significant correlations were found between the keratometries of donor corneas and post-keratoplasty corneas at postoperative month 1, 6, 12 and 24 (p=0,007; p=0,037; p=0,022 and p=0,036, Pearson correlation analysis, respectively). Mean difference between the donor cornea keratometries and post-keratoplasty corneas at the postoperative month 24 was 1.09 diopters and 95 % confidence interval of this difference was ranging from 0,27 to 1,92 diopters (=1,09 ± 0,83 diopters). Conclusion: Prediction of post-keratoplasty keratometries in the range of ± 1,00 diopter interval is possible at least in two years of postoperative period by using donor cornea keratometries as an indicator of final keratometry. Because of the absence of any other indicator for final post-keratoplasty keratometry, we recommend the obtaining of donor keratometries by eyebanks before the excision.

Keywords: Penetrating keratoplasty, portable keratometry, donor keratometry, graft Keratometry

Full Text (Turkish)