Correlation of virtual reality performance with real-life cataract surgery performance.

PURPOSE: To investigate the correlation between performance on a virtual reality simulator and real-life cataract surgical performance. SETTING: Nine ophthalmology departments in Denmark and Copenhagen Academy for Medical Education and Simulation, Copenhagen, Denmark. DESIGN: Prospective multicenter study. METHODS: Cataract surgeons with different experience levels were included. The participants performed 3 consecutive video-recorded phacoemulsification surgeries that were rated by masked raters using the Objective Structured Assessment of Cataract Surgical Skills (OSACSS) scoring system. Thereafter, the participants performed a previously validated test on an Eyesi virtual reality simulator. Primary outcomes were the mean OSACSS score from all 3 surgeries and the simulator score from the participants' first repetition of the performance test. RESULT: Nineteen surgeons participated. There was a statistically significant correlation between the simulator performance score and the mean OSACSS score across all experience levels, with a Pearson correlation of 0.65 (P = .003, R2 = 0.42). CONCLUSION: Simulator performance was significantly correlated with real-life cataract surgical performance.

A presentation of culture-positive corneal donors and the effect on clinical outcomes.

PURPOSE: Donor-to-host transmission of infectious agents is a rare but well-recognised complication of corneal transplantation and may carry a grave visual prognosis. In this case series, we describe the clinical features and risk factors of using culture-positive donor corneas for transplantation. METHODS: Retrospective chart review of a series of patients who underwent either penetrating keratoplasty (PK) or Descemet's stripping automated endothelial keratoplasty (DSAEK) with positive microbiology cultivation during routine assessment of donor corneal tissue obtained at the time of surgery. Donor and recipient characteristics, tissue preparation and surgical parameters, clinical signs and outcomes were registered. RESULTS: Eleven patients who received culture-positive corneal grafts were identified: six with Candida, three with Gram-positive bacteria and two with Gram-negative bacteria. Three patients developed clinical keratitis after routine DSAEK using corneas contaminated with Candida species. The median death-to-preservation time (DPT) of these three donor corneas was 18.08 (range 18.08 to 20.90) h, while in the remaining eight donors, it was 12.27 (range 9.32 to 20.47) h. Despite the initiation of antifungal treatment, all three cases required explantation of the graft and a subsequent re-DSAEK. CONCLUSIONS: The use of donor corneas that are culture-positive for Candida carries a risk for developing postoperative keratitis and the risk may be higher in DSAEK. Unlike the cold storage technique employed for donor corneas described in this case series, organ culture technique requires microbiological screening and supplementation of an antifungal agent which may reduce the risk of donor-to-host transmission of fungal infection.

Fungal infection after endothelial keratoplasty: association with hypothermic corneal storage.

PURPOSE: To compare the incidence of fungal infection after endothelial keratoplasty (EK) when donor tissue had been stored in hypothermic medium or organ culture. METHODS: We describe the clinical features of 10 cases of fungal infection (keratitis or endophthalmitis) following EK identified at three European centres. Case definition was the culture of fungus or a positive PCR from the host cornea or anterior chamber after EK. A survey of the incidence of infection after EK was conducted by the European Eye Bank Association. The main outcome measure was the number of cases in which donor tissue had been stored in hypothermic medium compared with organ culture. RESULTS: The 10 cases occurred between 2014 and 2017. All donor corneas had been stored in hypothermic medium sourced from three US eye banks. Three pairs of mate corneas caused infections in six recipients. Candida spp were identified from nine cases, with one isolate of Purpureocillium lilacinum. Data on 16 862 corneas supplied for EK were available from 16 European eye banks for the 5-year period from 2012. There were 17 reported cases of infection, of which 15 (88%) were fungal infections and 14 (82%) were Candida spp. Fungal infection was reported from 3 of 14 476 (0.02%) corneas supplied in organ culture compared with 12 of 2386 (0.50%) corneas supplied in hypothermic medium (p<0.0001). The incidence of infection after hypothermic storage was similar for material sourced from Europe (0.52%) or the USA (0.61%). CONCLUSIONS: Infection after EK is strongly associated with Candida spp. The possible explanations for the higher incidence of infection when tissue is stored in hypothermic medium are discussed.

Operating Room Performance Improves after Proficiency-Based Virtual Reality Cataract Surgery Training.

PURPOSE: To investigate the effect of virtual reality proficiency-based training on actual cataract surgery performance. The secondary purpose of the study was to define which surgeons benefit from virtual reality training. DESIGN: Multicenter masked clinical trial. PARTICIPANTS: Eighteen cataract surgeons with different levels of experience. METHODS: Cataract surgical training on a virtual reality simulator (EyeSi) until a proficiency-based test was passed. MAIN OUTCOME MEASURES: Technical performance in the operating room (OR) assessed by 3 independent, masked raters using a previously validated task-specific assessment tool for cataract surgery (Objective Structured Assessment of Cataract Surgical Skill). Three surgeries before and 3 surgeries after the virtual reality training were video-recorded, anonymized, and presented to the raters in random order. RESULTS: Novices (non-independently operating surgeons) and surgeons having performed fewer than 75 independent cataract surgeries showed significant improvements in the OR-32% and 38%, respectively-after virtual reality training (P = 0.008 and P = 0.018). More experienced cataract surgeons did not benefit from simulator training. The reliability of the assessments was high with a generalizability coefficient of 0.92 and 0.86 before and after the virtual reality training, respectively. CONCLUSIONS: Clinically relevant cataract surgical skills can be improved by proficiency-based training on a virtual reality simulator. Novices as well as surgeons with an intermediate level of experience showed improvement in OR performance score.

Promising results using the Hanna Corneal Trephine System in penetrating keratoplasty.

PURPOSE: To evaluate the outcome of penetrating keratoplasties using the Hanna Corneal Trephine System. METHODS: Fifty-five patients out of 70, who had penetrating keratoplasty performed by a single surgeon (KHO), from 1995 to 2001, were reviewed in 2002, at Department of Ophthalmology, Hospital of Hilleroed, Denmark. The reviews were performed by a single observer (NJ). All donor corneas were trephined from the epithelial side. Visual acuity, refraction, corneal astigmatism, and graft survival were main outcome measures. RESULTS: Seventy-two percent of the patients achieved a visual acuity > or =0.5. In major subgroups, that is, Fuchs endothelial dystrophy, secondary endothelial dystrophy, and keratoconus, a best corrected visual acuity of > or =0.5 was achieved in 57, 67, and 100%, respectively. The mean (+/-SD) postoperative spherical refraction was +0.84 D (+/-3.72), whereas mean keratometric and refractive astigmatism were -3.24 D (+/-1.51) and -3.06 D (+/-1.95), respectively. The overall graft survival rate was 96.7% after 2 years and 81.2% after 5 years. At least 90% of all patients were content with the result and course of the operation. CONCLUSIONS: The best corrected visual acuity was better, and the degree of astigmatism was less compared to previously reported studies. We suggest that these findings can be partly explained by the operative technique, that is, cutting the donor and the recipient cornea from the epithelial side by the use of an artificial chamber.