Incidence of Fungal Infection in Positive Donor Rim Cultures after Corneal Transplantation.

PURPOSE: To determine the clinical outcomes of corneal transplant patients that had positive rim cultures for fungi. METHODS: Retrospective study. RESULTS: Of 1276 rim cultures obtained between 2009 and 2019, 16 were positive for fungus (incidence of 1.25%). Clinical data were available for 12 patients. Candida and Cladosporium species were the most common organisms. Recipient ages ranged from 51 to 86 (median age 69 years; 9 males, 7 females). The most common surgery was Endothelial Keratoplasty (n = 8). There were no instances of fungal keratitis or endophthalmitis. Three patients were treated with prophylactic antimycotics. One patient developed bacterial keratitis. One patient had a varicella zoster virus reactivation without corneal involvement. CONCLUSIONS: This study adds to the growing data on the low rate of fungal keratitis and endophthalmitis after a corneal transplant, even in the case of positive rim cultures. This study also suggests that positive rim cultures do not advance the risk of postoperative fungal infection in the recipient.

The Antibacterial Comparison of 5% and 2.5% Povidone Iodine to 0.01% Hypochlorous Acid Using Corneoscleral Tissue as a Solid-Phase Medium.

PURPOSE: Prophylactic topical antiseptics used to eliminate bacteria on the ocular surface prior to ocular surgery should be both effective and non-irritating. Five percent povidone iodine (PI) is an accepted antiseptic used for prophylaxis. Dilute 2.5% PI and 0.01% hypochlorous acid (HOCl) may be more patient comfortable and equally effective. PI at 5% and 2.5% were compared to HOCl against a battery of bacterial endophthalmitis isolates using corneoscleral tissue as a solid-phase medium to determine antiseptic efficacy. METHODS: Bacteria from 20 cases of endophthalmitis were tested for the elimination of growth against topical 5% PI, 2.5% PI, HOCl, and no antiseptic using donor corneoscleral tissue. The tissue was inoculated with 103 colony forming units of bacteria prior to a 3-minute contact time with the antiseptics, placed in liquid growth medium, and monitored for growth at three days. No growth indicated antiseptic treatment success. Differences were analyzed using Chi square (χ2). RESULTS: For 20 isolates, 5% PI was comparable to 2.5% PI for preventing bacteria growth (p=0.71), and both were more effective than HOCl (p=0.004). Estimated weighted comparison over a 27-year period indicated that for all bacterial groups, except Streptococcus viridans, 5% PI was equally effective to 2.5% PI for preventing bacterial growth (p=1.0). For Streptococcus viridans, 5% PI was more effective than 2.5% PI (p=0.0001). Both concentrations of PI were more effective than HOCl (p=0.00001). CONCLUSION: Five percent PI appears to be optimal as a prophylaxis prior to ocular surgery.

Fungal infection after keratoplasty and the role of antifungal supplementation to storage solution: a review.

Fungal infection after corneal transplantation is a rare, yet potentially devastating, postoperative complication and has become a growing concern for the transplant surgeon and eye banking community. The Eye Bank Association of America (EBAA) has reported an increasing trend in the rate of postkeratoplasty fungal infections and a reversal in the previously documented predominance of bacterial over fungal infections. Additionally, several studies have confirmed a high correlation between positive corneoscleral donor rim fungal cultures and postoperative infections. Optisol GS (Bausch & Lomb, Irvine, California, USA), the most extensively used corneal storage solution in US eye banks, does not currently contain any antifungal supplementation. Although large randomised control trials evaluating the efficacy and safety of routine antifungal supplementation to corneal storage solution are lacking, several investigative studies have assessed the role of antifungal agents in reducing fungal contamination of donor corneas without causing undue corneal toxicity. This review will present the current epidemiology of postkeratoplasty fungal infections and evidence for obtaining routine fungal rim cultures and antifungal supplementation of storage solution.

Effect of Optisol Supplementation With 0.255 µg/mL Amphotericin B on Elimination of Yeast at 5°C.

PURPOSE: Fungal infections in lamellar keratoplasty are a growing concern. Optisol-GS does not contain an antifungal agent and supplementation with 0.255 µg/mL Amphotericin B (AmpB) has been considered. This study tested the ability of 0.255 µg/mL AmpB in Optisol-GS to eliminate yeast contamination of corneal tissue. METHODS: Three isolates of Candida albicans, 1 of Candida parapsilosis, and 1 of Candida glabrata were tested in Optisol with and without AmpB. Corneoscleral rims stored at -80°C were thawed and placed in 10 multiwell plates (4 per plate). The rims were inoculated with 4 respective loads of yeast: 0, 10, 10, and 10 colony-forming units in 2 sets of 5 for 5 yeasts. One set was filled with Optisol plus AmpB and the other with Optisol only. All 10 plates were incubated at cold storage (2°C-8°C) for 48 hours. After 48 hours, all corneal rims were placed into 10 mL of yeast extract peptone dextrose medium; a swab culture of each well was plated onto Sabouraud plates; and all plates with the remaining Optisol were incubated at 30°C. Yeast growth was monitored for 10 days. Minimum inhibitory concentration and minimum fungicidal concentration were determined. RESULTS: All corneoscleral specimens were positive regardless of fungal load or presence of AmpB. All controls remained negative. Minimum inhibitory concentrations and minimum fungicidal concentrations were equivalent and ranged between 0.5 and 2.0 µg/mL. CONCLUSIONS: AmpB at a concentration of 0.255 µg/mL in Optisol-GS at cold storage (2°C-8°C) over 48 hours did not eliminate yeast from corneal tissue.

Endothelial keratoplasty without Descemet stripping after failed penetrating keratoplasty.

PURPOSE: To evaluate outcomes of endothelial keratoplasty (EK) without Descemet membrane stripping for treatment of failed penetrating keratoplasty (PKP). METHODS: Retrospective cohort study of all eyes that underwent EK without Descemet membrane stripping for failed PKP at one institution between May 2008 and June 2010, with follow-up to 12 months. Main outcome measures were best-corrected visual acuity (BCVA), dislocation rate, and graft failure. RESULTS: Twenty-two eyes of 22 patients underwent non-Descemet stripping EK with a mean follow-up of 8.8 months (±3.41; range, 3-12 months). The mean preoperative BCVA was logarithm of the minimum angle of resolution (logMAR) 1.43 (±0.72; range, 0.3-3; Snellen, 20/537; N = 22). The mean postoperative BCVA was logMAR 0.97 (±0.88; range, 0-3; N = 21) at 1 month, 0.76 logMAR (±0.74; range, 0.1-3; N = 21) at 3 months, 0.75 (±0.77; range, 0-3; N = 17) at 6 months, and logMAR 0.55 (±0.38; range, 0.18-1; Snellen, 20/70; N = 9) at 1 year. Eight eyes (36.6%) had graft dislocations requiring one rebubbling procedure in 6 of 8 eyes and 2 rebubblings in the other 2 eyes. All grafts were successfully reattached. Graft failure occurred in 2 of 22 eyes (9%), with 1 eye (5%) undergoing repeat EK and 1 eye (5%) undergoing PKP. CONCLUSIONS: EK without Descemet membrane stripping is an effective option for management of eyes with failed PKP and may be a preferable alternative to a repeat PKP.

Glaucoma associated with Boston type I keratoprosthesis.

PURPOSE: To evaluate outcomes of the Boston type I keratoprosthesis (KPro) and associated incidence of glaucoma. DESIGN: Retrospective cohort study. PARTICIPANTS: All patients who underwent KPro surgery at 1 institution from 2003 to 2009 with at least 3 months of follow-up. METHODS: Preoperative visual acuity, diagnosis, history of glaucoma, and intraoperative and postoperative parameters were recorded. Statistical analysis was performed to identify factors that may influence increase in intraocular pressure (IOP) and glaucoma development or progression after surgery. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA), IOP, postoperative medical and surgical treatments for glaucoma, and KPro retention and complications. RESULTS: Thirty-six KPro procedures were performed in 30 eyes of 29 patients with a mean (±SD) follow-up of 17 ± 19 months (range, 3-67 months). The main indication for KPro implantation was corneal graft failure (77%). Primary KPro procedures were performed in 23% of eyes for limbal stem cell deficiency secondary to chemical burns and aniridia and for herpetic disease. Median preoperative BCVA was hand motions with an overall improvement to 20/330 (range, 20/20 to hand motions) at 9 months postoperatively; mean BCVA was 20/600 (range, 20/40 to NLP) at the last follow-up. Twenty eyes (67%) had a preoperative history of glaucoma, with 8 of those eyes (40%) having undergone previous glaucoma surgery. Twenty-one eyes (70%) underwent concomitant glaucoma surgery. Postoperative increased IOP (22 mm Hg or higher) was noted in 15 eyes (50%), although definite glaucoma development or progression was noted in 7 of those 15 eyes (23% of total eyes). Mean BCVA at the last follow-up in eyes with glaucoma development or progression was 3/200 compared with 20/563 in the remaining 23 eyes. Six patients (20%) required repeat KPro implantation, and retroprosthetic membranes developed in 23 eyes (77%). No patient had vitritis or infectious endophthalmitis develop. CONCLUSIONS: The Boston type I KPro is an effective option for management of eyes with poor prognosis for primary or repeat penetrating keratoplasty. Visual potential is limited by preoperative comorbidities; however, glaucoma development or progression of preexisting glaucoma is a significant cause of postoperative visual loss. Rigorous perioperative management of elevated IOP is essential for long-term success of KPro surgery.

Prevalence of corneal dystrophies in the United States: estimates from claims data.

PURPOSE: To estimate the prevalence of corneal dystrophies. METHODS: Records of almost 8 million enrollees in a national managed-care network throughout the United States who had an eye care visit in 2001 to 2009 were searched for a recording of corneal dystrophy on a claim submitted by an ophthalmologist or optometrist from January 1, 2001, through December 31, 2007. RESULTS: Unique individuals (n = 27,372) received two or more diagnoses of any type of corneal dystrophy, for an overall corneal dystrophy prevalence rate of 897 per million (106) covered lives. Endothelial and anterior corneal dystrophies accounted for most of the reported dystrophies, and granular corneal dystrophy was the least common, being reported in 167 enrollees. Age, sex, and race variations among the various corneal dystrophies were observed. The mean age of those with macular corneal dystrophy (47.3 years) was 15 years younger than the age of those with endothelial dystrophy (62.9 years), and females were most highly represented (68.5%) among those with lattice corneal dystrophy. Hispanics and blacks were underrepresented relative to enrollees undergoing eye care for reasons other than corneal dystrophy. Keratoplasty was most frequently coded among those with lattice dystrophy. CONCLUSIONS: Although caveats must be considered in using claims data to estimate prevalence in a population, these data provide an indication of corneal dystrophy's prevalence within insured subjects across the United States. Variations in age, sex, and race, within and between the different types of corneal dystrophies, raise questions that warrant further study.

Bilateral mesial occipital lobe infarction after cardiogenic hypotension induced by electrical shock.

A 28-year-old man developed cerebral blindness from infarction of both mesial occipital lobes after cardiogenic hypotension induced by electrical shock. He remained globally encephalopathic for several weeks, but his most enduring deficit was bilateral homonymous hemianopias with macular sparing. Cerebral visual loss after electrical injury has been sparsely reported. It has been attributed to direct thermal injury of the skull or posterior dural venous sinuses. We suggest that cerebral blindness after cardiogenic hypotension in which there is no thermal injury to the scalp be attributed to hypotensive infarction of the mesial occipital lobes, which lie in the terminal domain of the posterior cerebral arteries.

Sustained microtubule treadmilling in Arabidopsis cortical arrays.

Plant cells create highly structured microtubule arrays at the cell cortex without a central organizing center to anchor the microtubule ends. In vivo imaging of individual microtubules in Arabidopsis plants revealed that new microtubules are initiated at the cell cortex and exhibit dynamics at both ends. Polymerization-biased dynamic instability at one end and slow depolymerization at the other end result in sustained microtubule migration across the cell cortex by a hybrid treadmilling mechanism. This motility causes widespread microtubule repositioning and contributes to changes in array organization through microtubule reorientation and bundling.