title: Surface metrology and 3-dimensional confocal profiling of femtosecond laser and mechanically dissected ultrathin endothelial lamellae.
abstract: OBJECTIVE
  To determine the feasibility of confocal profiling in measuring surface roughness and obtaining 3-dimensional reconstructions of mechanically dissected and femtosecond (fs)-laser photodisrupted endothelial lamellae. To determine the predictability of single-pass dissection of ultrathin endothelial lamellae using a novel motor-driven linear microkeratome.
  
  
  METHODS
  Thirty (n = 30) human corneas were harvested using a motor-driven linear microkeratome (n = 20); a hand-driven rotatory microkeratome (n = 6); and a 60-kHz fs laser (n = 4). Surface roughness was measured using an optical profiler operated in confocal microscopy mode followed by environmental scanning-electron-microscopy.
  
  
  RESULTS
  Mean surface roughness for the fs laser, motor-driven linear microkeratome, and hand-driven rotatory microkeratome measured 1.90 ± 0.48 μm, 1.06 ± 0.42 μm, and 0.93 ± 0.25 μm, respectively. Femtosecond photodisrupted lamellae were significantly rougher than mechanically dissected lamellae (P < 0.001). Mean (±SD) cutting depth with the motor-driven linear microkeratome measured: 552 ± 11 μm (550-μm head); 505 ± 19 μm (550-μm head); 459 ± 19 μm (450-μm head); and 392 ± 20 μm (400-μm head).
  
  
  CONCLUSIONS
  Confocal microscopy allows quantitative surface roughness analysis and 3-dimensional reconstruction of human corneal lamellae. Femtosecond-laser photodisruption at 60 kHz results in rougher surfaces compared with mechanical dissection. The motor-driven linear microkeratome allows single-pass dissection of ultrathin endothelial lamellae with a standard deviation ≤20 μm.
authors: Maastricht University Medical Center, University Eye Clinic Maastricht, Maastricht, The Netherlands.
authors: Mor M
authors: MM
authors: Dickman
authors: Eindhoven University of Technology, Department of Mechanical Engineering, Multiscale Laboratory, Eindhoven, The Netherlands.
authors: Marc P F H L
authors: MP
authors: van Maris
authors: Euro Cornea Bank, Beverwijk, The Netherlands.
authors: Friso W
authors: FW
authors: van Marion
authors: Euro Cornea Bank, Beverwijk, The Netherlands.
authors: Yvonne
authors: Y
authors: Schuchard
authors: Euro Cornea Bank, Beverwijk, The Netherlands.
authors: Petra
authors: P
authors: Steijger-Vermaat
authors: Maastricht University Medical Center, University Eye Clinic Maastricht, Maastricht, The Netherlands.
authors: Frank J H M
authors: FJ
authors: van den Biggelaar
authors: Maastricht University Medical Center, University Eye Clinic Maastricht, Maastricht, The Netherlands.
authors: Tos T J M
authors: TT
authors: Berendschot
authors: Maastricht University Medical Center, University Eye Clinic Maastricht, Maastricht, The Netherlands.
authors: Rudy M M A
authors: RM
authors: Nuijts
mesh_terms: D057111:Descemet Stripping Endothelial Keratoplasty / Q000379:methods*; D004728:Endothelium, Corneal / Q000601:surgery / Q000648:ultrastructure*; D005240:Feasibility Studies; D006801:Humans; D054018:Lasers, Excimer; D018613:Microscopy, Confocal; D013499:Surface Properties; D020858:Tissue and Organ Harvesting / Q000379:methods*
keywords: endothelial keratoplasty; femtosecond laser; mechanical microkeratome; surface metrology; ultrathin grafts