Abstract
Purpose: :
To compare anterior lamellar keratoplasty (ALK) with penetrating keratoplasty (PK) in eyes with corneal diseases not involving the corneal endothelium.
Methods: :
Retrospective comparative case series including149 consecutive ALKs and 149 matched PKs performed for optical indication in eyes with keratoconus, scars after infectious keratitis, stromal dystrophies, or trauma. Three surgical techniques were used for performing ALK: the big bubble technique (BB), manual lamellar dissection using a slitlamp (MD), and automated lamellar dissection using a microkeratome (AD). Five year graft survival, manifest refraction, slitlamp examination, tonometry, ultrasound pachymetry, specular microscopy, optical coherence tomography, and confocal microscopy findings were recorded.
Results: :
The 60-month graft survival estimate was 98.5% in the ALK group and 91.5% in the PK group (p=0.02). The 3-year cumulative incidence of irreversible rejection was 0.0% in the ALK group and 5.2% in the PK group (p=0.02). The average 1-, 3-, and 5-year post-operative endothelial cell loss was, respectively, 10%, 17%, and 21% in the ALK group and 21%, 37%, and 49% in the PK group (p<0.0001). In keratoconus eyes, the average increase in visual acuity at 24 months was 10 lines in the BB subgroup, 9 lines in the MD subgroup and 10 lines in the PK group (p=0.66). The average thickness of the recipient residual stroma in the 3-mm zone was 214 µm in the microkeratome subgroup and101 µm in the manual dissection subgroup.
Conclusions: :
ALK techniques dramatically decrease the risk of irreversible rejection after corneal transplantation and better preserve the corneal endothelium in the long term.
Keywords: cornea: clinical science • cornea: endothelium • transplantation