title: Comparison of fresh corneal tissue versus glycerin-cryopreserved corneal tissue in deep anterior lamellar keratoplasty.
abstract: OBJECTIVE
  To compare the microstructural differences in fresh corneal tissue (FCT) with glycerin-cryopreserved corneal tissue (GCCT) used during deep anterior lamellar keratoplasty (DALK).
  
  
  METHODS
  The medical records of 48 consecutive patients who underwent DALK for stromal opacity without endothelial abnormalities were retrospectively reviewed. Patients were divided into two groups: an FCT group (n = 22) and a GCCT group (n = 26), according to the corneal tissue used. The best corrected visual acuity (BCVA), slit lamp, corneal topography, pachymetry, and laser scanning in vivo confocal microscopy examinations at 2 weeks and 1, 3, 6, 12, and 24 months after surgery were analyzed.
  
  
  RESULTS
  No graft rejection developed in the GCCT group, whereas stromal rejection developed in one eye in the FCT group. There were no significant differences in spherical equivalent (P = 0.37), astigmatism (P = 0.26), BCVA (P = 0.64), central corneal thickness (P = 0.73), or endothelial cell density (P = 0.49) between the two groups at 24 months. Confocal microscopy showed that GCCT was acellular, whereas dendritelike cells and keratocytes were found in the FCT group 2 weeks after surgery. The keratocyte density improved significantly in the GCCT group at 3 months after surgery, whereas it decreased significantly after surgery in the FCT group during follow-up. No significant difference in regeneration of nerve fibers was found in the subbasal layer and anterior stroma between the two groups at 24 months.
  
  
  CONCLUSIONS
  DALK using GCCT provides clinical results comparable to FCT. GCCT can be used safely and effectively for DALK and may minimize stromal rejection after surgery.
authors.affiliation: School of Ophthalmology and Optometry, Wenzhou Medical College, Zhejiang, China. chenweimd@hotmail.com
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Ying
authors.initials: Y
authors.lastname: Lin
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zhang
authors.forename: Lihua
authors.initials: L
authors.lastname: Wang
authors.forename: Mimi
authors.initials: M
authors.lastname: Liu
authors.forename: Jingbo
authors.initials: J
authors.lastname: Liu
authors.forename: Ya
authors.initials: Y
authors.lastname: Ye
authors.forename: Li
authors.initials: L
authors.lastname: Sun
authors.forename: Huixiang
authors.initials: H
authors.lastname: Ma
authors.forename: Jia
authors.initials: J
authors.lastname: Qu
mesh_terms: D000328:Adult; D002452:Cell Count; D003315:Cornea; D003318:Corneal Opacity / Q000601:surgery*; D003319:Corneal Stroma / Q000473:pathology; D019781:Corneal Topography; D016039:Corneal Transplantation / Q000379:methods*; D015925:Cryopreservation; D003451:Cryoprotective Agents / Q000627:therapeutic use*; D004728:Endothelium, Corneal / Q000166:cytology; D005260:Female; D005990:Glycerol / Q000627:therapeutic use*; D006085:Graft Survival / Q000502:physiology; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D014019:Tissue Donors; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
chemical_list: D003451:Cryoprotective Agents; D005990:Glycerol