Changes of Contamination Rate and Microorganism Evaluation in Organ-Cultured Human Corneas: A 14-Year Review From a French Regional Eye Bank.

PURPOSE: This study aimed to assess how the contamination rate of organ-cultured corneas has evolved and to analyze the evolution of microorganisms involved. METHODS: Data from the Besançon eye bank were reviewed over 14 years (2005-2018). The changes in the contamination rate and the contaminant species found during the organ culture storage were analyzed. Microbiological tests were performed twice on the storage media-at day 5 and before the deswelling phase. RESULTS: Among the 17,979 donor corneas collected, 1240 corneas were microbiological-test positive. The average annual contamination rate was 6.8% (range: 5.2%-8.9%). Seventy-five percent of contaminations were bacterial. The most frequently found bacterium was Staphylococcus spp. (31.3%), followed by non-Enterobacteriaceae Gram-negative Bacilli (GNB) (27.3%), with most Sphingomonas spp. and Pseudomonas spp. Fungal contamination (21.9%) was dominated by Candida (82.7%). Seventy-seven types of microorganisms were identified. The Staphylococcus rate tended to decrease, whereas non-Enterobacteriaceae GNB rate has increased in the past few years to reach 46% of bacteria. Most of the contaminations were detected in the early phase of organ culture at day 5 (89.2%). The second microbiological test found 44.8% of fungal contaminations (predominantly Candida spp.). CONCLUSIONS: The annual contamination rate was stable and remains low, but the types of contaminating microorganisms varied from year to year. Staphylococcus spp. and non-Enterobacteriaceae GNB accounted for a significant proportion of the contaminations. We found a significant proportion of contamination, especially fungal, at the late phase of storage. Reassessing the antibiotics and antifungals in the storage medium may be useful to limit corneal disposal.

Da Vinci Xi Robot-Assisted Penetrating Keratoplasty.

PURPOSE: This study aims (1) to investigate the feasibility of robot-assisted penetrating keratoplasty (PK) using the new Da Vinci Xi Surgical System and (2) to report what we believe to be the first use of this system in experimental eye surgery. METHODS: Robot-assisted PK procedures were performed on human corneal transplants using the Da Vinci Xi Surgical System. After an 8-mm corneal trephination, four interrupted sutures and one 10.0 monofilament running suture were made. For each procedure, duration and successful completion of the surgery as well as any unexpected events were assessed. The depth of the corneal sutures was checked postoperatively using spectral-domain optical coherence tomography (SD-OCT). RESULTS: Robot-assisted PK was successfully performed on 12 corneas. The Da Vinci Xi Surgical System provided the necessary dexterity to perform the different steps of surgery. The mean duration of the procedures was 43.4 ± 8.9 minutes (range: 28.5-61.1 minutes). There were no unexpected intraoperative events. SD-OCT confirmed that the sutures were placed at the appropriate depth. CONCLUSIONS: We confirm the feasibility of robot-assisted PK with the new Da Vinci Surgical System and report the first use of the Xi model in experimental eye surgery. Operative time of robot-assisted PK surgery is now close to that of conventional manual surgery due to both improvement of the optical system and the presence of microsurgical instruments. TRANSLATIONAL RELEVANCE: Experimentations will allow the advantages of robot-assisted microsurgery to be identified while underlining the improvements and innovations necessary for clinical use.

Corneal transplantation: study of the data of a regional eye bank for the year 2013 and analysis of the evolution of the adverse events reported in France since 2010.

To analyze the data of the adverse events collected in a single major eye bank (EFS Bourgogne Franche Comté, Besançon, France) for the year 2013 and to report the French data of biovigilance provided by the French National Agency for Medicines and Health Products Safety (ANSM) between 2010 and 2013. we have set up a study of adverse events in 2013, in collaboration with a single eye bank (EFS Bourgogne Franche Comté, Besançon, France). A survey was sent to the surgeon for each delivered corneal button by the eye bank in 2013. They were asked for each grafted patient performed in their center, the type of graft (penetrating keratoplasty, anterior keratoplasty or endothelial keratoplasty), the occurrence of adverse events (primary failure, infectious keratis, endophthalmitis, immune rejection, and other events) and the time interval between surgery and events (Less than 1 postoperative month, between 1 month and 1 year postoperatively, >1 year postoperatively). In 2013, 407 corneal buttons were delivered by the eye bank of Besançon in 21 medical centers which performed corneal grafts and we sent 407 surveys. We received 243 completed questionnaires (59.75%) from 11 centers (52.38%). The global reported rate of adverse events was 27.54% of the graft (n = 65/236 corneal grafts performed in 11 centers in 2013; 20% of Primary graft failure, 11% of infectious keratitis, 1% of endophthalmitis, 34% of rejection, 34% of other incidents). 30.16% of complications were noticed before the first month after surgery versus 52.38% of complications noticed between the first month and the first year after surgery and 17.46% of complications noticed after the post-operative first year The most common causes of adverse events after PK were Immune rejection (13.17%), surgical causes (5.98%) and infection (4.79%) and after EK were Primary graft failure (8.2%) and surgical causes (19.67%). In 2013, in France 0.83% of adverse events were notified in ANSM. For the 236 performed graft issued from a major eye bank (EFS Besançon) in 2013 the global reported rate of post-graft adverse events was 27.54% of the grafts (20% of Primary graft failure, 11% of infectious keratitis, 1% of endophthalmitis, 34% of rejection and 34% of other incidents). Compared to the ANSM data (0.83% of adverse events reported in 2013) this rate is high. This difference can be explained by the low rate of annual notification to the ANSM and shows that biovigilance in France must be more developed. Since biovigilance needs constant improvement for the safety of the graft system, training, information for practitioners, simplifications of procedures and international standardization of the definition are the main points that could be improved.