To determine the advantages, safety, and accuracy of deep anterior lamellar keratoplasty (DLK) versus penetrating keratoplasty (PK) in terms of visual acuity, astigmatism, and endothelial preservation in corneal diseases with healthy endothelium. Of these candidates for keratoplasty, the study investigated keratoconus patients with no other ophthalmic abnormalities. This comparative nonrandomized retrospective study investigated 22 patients with keratoconus requiring surgery, who underwent keratoplasty in the Nantes University Hospital between 1 June 2002 and 1 January 2004. Ten DLK, ten PK and two PK converted DLK cases were analyzed. Follow-up at 2 weeks and at 3, 6, 9, and 18 months is reported for visual acuity, astigmatism, pachymetry, specular microscopy, and intraocular pressure (IOP). Data are compared before and after surgery at each follow-up date. Preoperative visual acuity improved in both groups from 0.14+/-0.13 to 0.8+/-0.17 postoperatively. There was no significant difference between the two groups before and at each time after surgery for visual acuity and astigmatism (3.5+/-2 diopters in the PK group and 3+/-0.9 D in the DLK group). There was a statistical difference for IOP with two occurrences of increased IOP up to 30 mmHg in the PK group. Endothelial cell count analysis showed an immediate postoperative decrease of 10% in the DLK group (versus approximately 40% in the PK group), remaining rather stable the 1st year (-3.3%), although cell loss in the PK group declined up to 10% more at 18 months. With no statistical difference between the two groups for visual acuity and astigmatism, DLK is effective. It is safer than PK in terms of IOP disturbance (leading cause of graft failure) and endothelial cell loss. DLK converted into PK (16%) showed the same profile as first-intention PK. Despite very similar effectiveness, DLK in keratoconus surgery should be proposed rather than PK because it appears safer not only in the short term but also probably in the long term, with no risk of endothelial cell rejection.
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