Survivability of locally prepared versus imported Descemet membrane endothelial keratoplasty grafts in Edmonton.

OBJECTIVE: This study aimed to evaluate the long-term graft survivability of locally prestripped versus imported prestripped Descemet membrane endothelial keratoplasty (DMEK) grafts in Edmonton. DESIGN: Prospective cohort study of patients who underwent DMEK surgery between January 1, 2020, and December 31, 2020. PARTICIPANTS: All patients receiving a DMEK transplant during the study period in Edmonton. METHODS: Two local technicians were trained to prestrip DMEK grafts in Edmonton. When available, local tissue was prestripped for DMEK surgery; otherwise, prestripped DMEK grafts were imported from an accredited American eye bank. Patient characteristics and DMEK graft characteristics and DMEK survivability were evaluated and compared between the 2 groups. RESULTS: Thirty-two locally prestripped DMEK grafts and 35 imported prestripped DMEK grafts were used during the study period. Donor cornea characteristics and patient characteristics were similar between the 2 groups. Best-corrected visual acuity improved up to 6 months postoperatively and was 0.2 logMAR in the locally prestripped DMEK group and 0.2 logMAR in the imported DMEK group (p = 0.56). Rebubble rates were 25% in the locally prestripped DMEK group and 19% in the imported DMEK group (p = 0.43). There was 1 primary graft failure in each group (p = 0.93). Endothelial cell density decreased by 37% in the locally prestripped DMEK group and by 33% in the imported DMEK group 2 years after transplantation. CONCLUSIONS: The long-term survivability of locally prepared DMEK grafts is comparable with that of DMEK grafts imported from American eye banks.

Cost-effectiveness of locally prepared Descemet membrane endothelial keratoplasty grafts in Edmonton.

OBJECTIVE: This study aimed to show the cost-effective benefits of creating a sustainable local program where Descemet membrane endothelial keratoplasty (DMEK) grafts were prepared locally instead of imported from American eye banks. DESIGN: Retrospective observational study. METHODS: In 2018, 2 local technicians were trained to prestrip DMEK grafts in Edmonton up to 2 days before surgery when local donor tissue was available. When no local tissue was available, prestripped DMEK grafts were imported from U.S. eye banks. The total cost of locally prepared and imported DMEK grafts over 27 months was compared with the cost that otherwise would have been accrued if all DMEK grafts had been imported. RESULTS: Over 27 months, 82 DMEK grafts (55.3%) were prepared locally and 63 DMEK grafts (44.7%) were imported. The total cost of preparing 82 grafts locally was $9349.19. The total cost of importing 63 prestripped DMEK grafts was $282 431.52. The combined total cost of locally prepared and imported DMEK grafts was $291 780.71. The total cost that otherwise would have been incurred if every graft was imported was $632 108.64. This difference in costs was $340 327.93 over 27 months. CONCLUSIONS: Establishing a sustainable program to make high-quality DMEK grafts with local donor corneas is a cost-effective alternative to importing prestripped DMEK grafts in Edmonton.

Post-traumatic fungal keratitis caused by Carpoligna sp.

PURPOSE: To report the first case of fungal keratitis caused by presumed Carpoligna species. METHODS: A 37-year-old gardener sustained a full-thickness, stellate corneal laceration while cutting wood outdoors with a circular saw. Two months after surgical repair, he developed a severe infectious keratitis with descemetocoele at the apex of the original stellate laceration. RESULTS: Culture results confirmed fungal elements without evidence of bacteria. Oral and topical voriconazole were initiated. Due to compliance and cost issues, voriconazole was replaced with natamycin 5% prior to discharge from hospital. The patient improved and healed without perforation. The patient was left with a central stromal scar. DNA extraction from the fungal colony allowed PCR amplification of the 28s ribosomal RNA region of the fungus that led to the diagnosis of Carpoligna pleurothecii. Corticosteroids were never used during the patient's treatment. CONCLUSION: This is the first reported case of infectious keratitis caused by presumed Carpoligna species. The treatment for Carpoligna pleurothecii keratitis includes voriconazole, natamycin, and possibly amphotericin B.

Mutational analysis of patients with the diagnosis of choroideremia.

All reported mutations in the choroideremia (CHM) gene result in the truncation or complete absence of Rab escort protein 1 (REP1). Molecular analysis was carried out on 57 families diagnosed with CHM. Confirmation of the clinical diagnosis is important as end-stage CHM may be clinically similar to the end stages of other retinal degenerative diseases such as RP. The primary means of confirming the diagnosis of CHM is to sequence all 15 exons. An alternative method involves detection of the REP1 protein, as described in MacDonald et al. [1998]. A monoclonal antibody to REP1 does not detect truncated REP1 by immunoblot analysis, presumably due to instability and subsequent degradation of the truncated protein. This analysis provides relatively fast confirmation of the diagnosis, however, protein samples are not always available and are susceptible to degradation, affecting the accurate interpretation of results. CHM gene mutations were found in 54 of 57 families studied. The majority of mutations (>42%) were transitions and transversions. Complete deletions of the CHM gene and deletion/insertion mutations each accounted for almost 4% of the total, while over 9% had large intragenic and other partial deletions. Almost 28% of the mutations were deletions of fewer than 5 base pairs (bp) and almost 13% were splice site mutations. Despite the fact that mutations are found throughout the gene with no common mutation for the disorder, identical mutations have been characterized in unrelated individuals. The majority of these mutations are C to T transitions, changing an arginine residue (CGA) to a stop codon (TGA). Four of the five CGA codons in the CHM gene are sites of recurring mutations.