title: Ultra-thin donor tissue preparation for endothelial keratoplasty with a double-pass microkeratome.
abstract: OBJECTIVE
  To quantify and describe practically a novel technique for donor tissue preparation in Descemet stripping endothelial keratoplasty to approach the superior visual outcomes of Descemet membrane endothelial keratoplasty.
  
  
  METHODS
  Experimental laboratory investigation.
  
  
  METHODS
  
  
  
  METHODS
  Institutional.
  
  
  METHODS
  Eleven human donor corneas.
  
  
  METHODS
  Double-pass of microkeratome over donor corneas-first with a thicker cutting depth and subsequently with a thinner cutting depth.
  
  
  METHODS
  Donor tissue profiles and residual bed thicknesses.
  
  
  RESULTS
  After the first pass of the microkeratome, the average cut thickness using the 250-μm cutting head was 342.5 ± 14.8 μm (range, 332 to 353 μm), that using the 300-μm head was 343.8 ± 39.2 μm (range, 315 to 411 μm), and that with the 350-μm head was 467.7 ± 50.1 μm (range, 419 to 519 μm). We used the 200-μm cutting head only once with a cut depth of 210 μm. For the second pass, when using the 110-μm head, the cutting depth averaged to 167.8 ± 28.8 μm (range, 133 to 203 μm). The 130-μm cutting head yielded a cut depth of 199.7 ± 24.4 μm (range, 180 to 227 μm). Two corneas were perforated during the second pass. The average final thickness of the residual bed was 121 ± 32.2 μm (range, 52 to 160 μm).
  
  
  CONCLUSIONS
  Double-pass harvest for ultra-thin Descemet stripping automated endothelial keratoplasty could improve optical outcomes by obtaining donor Descemet stripping automated endothelial keratoplasty tissue with thinner residual beds. Further studies are needed with larger sample sizes to establish algorithms for appropriate cutting head thickness in each pass. Potential additional endothelial cell loss with the second pass of the microkeratome also should be evaluated.
authors.affiliation: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah 84132, USA.
authors.forename: Shameema
authors.initials: S
authors.lastname: Sikder
authors.forename: Rick N
authors.initials: RN
authors.lastname: Nordgren
authors.forename: Shantanu R
authors.initials: SR
authors.lastname: Neravetla
authors.forename: Majid
authors.initials: M
authors.lastname: Moshirfar
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D057111:Descemet Stripping Endothelial Keratoplasty / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D008875:Middle Aged; D010865:Pilot Projects; D014019:Tissue Donors; D020858:Tissue and Organ Harvesting / Q000379:methods*; D041623:Tomography, Optical Coherence; D055815:Young Adult