Publications by authors named "Peter Bedard"
Purpose: The aims of this study were 1) to compare area of cell loss (ACL) on trypan staining with ACL on specular imaging and 2) to evaluate the use of automated software for measuring ACL on trypan staining.
Methods: Donor corneas with transplant-grade endothelium were mechanically injured with an 18-gauge cannula and a Fogla deep anterior lamellar keratoplasty dissector tip to create an easily identifiable "bullseye" pattern of cell death. Each cornea was then stained with trypan blue 0.
Purpose: To characterize the pattern and factors affecting endothelial cell loss (ECL) in pre-Descemet Endothelial Keratoplasty (PDEK) graft preparation.
Methods: A prospective study was performed to characterize the pattern of ECL and the impact of inflation pressure in PDEK. Donor corneas were randomized to inflation with air versus Optisol GS storage media.
Purpose: To evaluate the ex vivo safety and efficacy of using paired peripheral incisions to achieve a triple scroll conformation that facilitates unscrolling in Descemet membrane endothelial keratoplasty (DMEK).
Methods: The safety of adding paired peripheral incisions to DMEK grafts was evaluated by assessing endothelial cell loss (ECL) and risk of tearing. ECL was measured using calcein-AM staining after incisions.
Purpose: To compare the variation in corneal endothelial cell density (ECD) from the center to the periphery in unpeeled and peeled donor corneas and to determine the impact of eccentric trephining on total endothelial cells in Descemet membrane endothelial keratoplasty (DMEK) grafts.
Methods: Mated donor cornea pairs were obtained. One cornea from each pair was peeled for DMEK, whereas the other was left unpeeled.
Article Synopsis
- The study aimed to compare the endothelial cell density (ECD) measurements between eye banks (EBs) and a reading center as part of the Cornea Preservation Time Study.
- Results showed that EBs typically recorded a higher mean preoperative ECD by 15 cells/mm compared to the reading center, with noticeable variability in individual measurements.
- Agreement between the two methods improved when analyzing more than 100 cells, indicating more consistent results with larger sample sizes.
Purpose: To describe and report outcomes of our single-pass microkeratome technique for preparation of ultrathin (UT, ≤100 μm) and nanothin (NT, ≤50 μm) Descemet stripping automated endothelial keratoplasty (DSAEK) grafts.
Methods: To prepare NT-DSAEK grafts, a pachymetry nomogram specific to each technician and individual microkeratome head was developed based on accumulated precut and postcut pachymetry data from previous DSAEK grafts. Mean graft thickness as well as precut and postcut endothelial cell counts (ECCs) of NT-DSAEK, UT-DSAEK, and Descemet membrane endothelial keratoplasty (DMEK) grafts between July 2015 and July 2017 were calculated and compared statistically.