Purpose. To assess the intraoperative results comparing two non-mechanical
laser assisted
penetrating keratoplasty approaches in
keratoconus and
Fuchs dystrophy. Patients and Methods. 68 patients (age 18 to 87 years) with
keratoconus or
Fuchs dystrophy were randomly distributed to 4 groups. 35 eyes with
keratoconus and 33 eyes with
Fuchs dystrophy were treated with either
excimer laser ([Exc] groups I and II) or femtosecond
laser-assisted ([FLAK] groups III and IV)
penetrating keratoplasty. Main intraoperative outcome measures included intraoperative decentration, need for additional interrupted
sutures, alignment of orientation markers, and intraocular positive pressure (vis a tergo). Results. Intraoperative recipient decentration occurred in 4 eyes of groups III/IV but in none of groups I/II. Additional interrupted
sutures were not necessary in groups I/II but in 5 eyes of groups III/IV. Orientation markers were all aligned in groups I/II but were partly misaligned in 8 eyes of groups III/IV. Intraocular positive pressure grade was recognized in 12 eyes of groups I/II and in 19 eyes of groups III/IV. In particular, in group III, severe vis a tergo occurred in 8 eyes. Conclusions. Intraoperative decentration, misalignment of the donor in the recipient bed, and need for additional interrupted
sutures as well as high percentage of severe intraocular positive pressure were predominantly present in the femtosecond
laser in
keratoconus eyes.