Manual top hat wound configuration for penetrating keratoplasty.

PURPOSE: To compare the outcomes of manual top hat penetrating keratoplasty (PK) versus traditional PK.

METHODS

We reviewed the charts of 71 consecutive patients who underwent manual top hat (n = 36) or traditional (n = 35) PK at our institute. Main outcome measures included best-corrected Snellen visual acuity (BCVA), topographic and refractive results, high-order ocular aberrations, endothelial cell counts, and complication rate.

RESULTS

No difference in mean BCVA between the 2 groups was noted after 12 months of follow-up. The mean spherical equivalent power was mild myopia, and the mean astigmatism was <4.2 D cylinder in both groups. There was no difference in total high-order aberrations, except spherical aberrations: 0.88 +/- 0.74 microm in the top hat versus 0.49 +/- 0.41 microm in the traditional PK (P = 0.01). Endothelial cell count was significantly higher in top hat PK group (1978 +/- 277 vs. 1449 +/- 516/mm2 in traditional PK; P < 0.0001), and time to all suture removal was shorter (3.9 +/- 1.5 vs. 9.7 +/- 1.1 months in traditional PK; P < 0.0001).

CONCLUSIONS

BCVA and refractive results are similar after manual top hat and traditional PK. Top hat PK speeds up suture removal and contributes to higher endothelial cell counts in the grafts 1 year after surgery.