Adult stem cells in the eye: Identification, characterisation, and therapeutic application in ocular regeneration - A review.

Adult stem cells, present in various parts of the human body, are undifferentiated cells that can proliferate and differentiate to replace dying cells within tissues. Stem cells have specifically been identified in the cornea, trabecular meshwork, crystalline lens, iris, ciliary body, retina, choroid, sclera, conjunctiva, eyelid, lacrimal gland, and orbital fat. The identification of ocular stem cells broadens the potential therapeutic strategies for untreatable eye diseases. Currently, stem cell transplantation for corneal and conjunctival diseases remains the most common stem cell-based therapy in ocular clinical management. Lens epithelial stem cells have been applied in the treatment of paediatric cataracts. Several early-phase clinical trials for corneal and retinal regeneration using ocular stem cells are also underway. Extensive preclinical studies using ocular stem cells have been conducted, showing encouraging outcomes. Ocular stem cells currently demonstrate great promise in potential treatments of eye diseases. In this review, we focus on the identification, characterisation, and therapeutic application of adult stem cells in the eye.

Cysts and tumours of the iris: Diagnostic tools and key management considerations-A review.

The iris is a unique structure, with exquisite variations in colour and form. Pathological changes, specifically including iris cysts and tumours are relatively uncommon, difficult to diagnose, and yet potentially blinding or life-threatening. Based on a comprehensive literature review, with highly illustrated key case examples, this report aims to guide the clinician in filtering the differential diagnoses of iris cysts and tumours. Evaluation is in the context of key diagnostic clinical tools and management considerations. Diagnostic imaging techniques include serial anterior segment photography, ultrasound, anterior segment optical coherence tomography, and iris fluorescein angiography, however, the roles of computerised topography and magnetic resonance imaging are also considered in this review. Management includes categorisation in terms of solid iris tumours (melanocytic vs. non-melanocytic), or iris cysts (primary vs. secondary) that may be usefully differentiated by clinical assessment, avoiding more invasive interventions. Cystic lesions are generally benign, although implantation cysts in particular cause significant complications and surgical challenges. Most solid tumours are melanocytic and also typically benign. However, in larger lesions, rapid growth, symptoms and complications more likely indicate malignancy, requiring further investigation.

Keratoconus in Down syndrome: Prevalence, risk factors, severity and corneal tomographic characteristics.

BACKGROUND: This study investigated the prevalence, risk factors and severity of corneal tomographic features of keratoconus in Down syndrome (DS). Additionally, previous studies indicate anomalous corneal features in DS, without keratoconus, this study characterised corneal features in DS without keratoconus. METHODS: This prospective observational study included participants with DS ≥10 years old. Keratoconus diagnosis, risk factors and corneal tomographic characteristics were recorded. Participants underwent slit-lamp biomicroscopy, Scheimpflug corneal tomography, corneal topography and autorefraction. A diagnosis of keratoconus (DS-KC), suspect keratoconus (DS-SK) and non-keratoconus (DS-NK) was made based on expert review of scans by three fellowship trained anterior segment ophthalmologists. Corneal tomography parameters from one eye of each participant were analysed. RESULTS: Keratoconus affected 50 (26.3%) of 190 participants, diagnosed by corneal tomography, topography or slit-lamp signs. Corneal hydrops affected 14.0% of DS-KC participants. Eye rubbing was a significant risk factor for keratoconus (p = 0.036). 175 (92%) participants could undertake corneal tomography of which tomography assessment alone identified 47 (26.9%) DS-KC participants, 64 (36.6%) DS-SK participants and 64 (36.6%) DS-NK participants. Significant differences (p < 0.001) were identified when the DS-KC, DS-SK and DS-NK groups were compared in maximum keratometry and posterior elevation at the thinnest point respectively: median (interquartile range) 50.20 (10.30D), 47.60 (1.95D), 46.50 (2.40D); 24.0 (38.00 µm), 10.00 (13.75 µm), 8.00 (6.00 µm). The DS-SK and DS-NK cohorts had similar minimum pachymetry, however, had several significantly different parameters among which included greater maximum keratometry, posterior elevation at the thinnest point in the DS-SK group. CONCLUSIONS: Keratoconus is common in DS. Keratoconus screening with corneal tomography is recommended for early detection.

Keratoconus Management in the Community: A Survey of Optometrists.

OBJECTIVES: Defining the patterns of practice and referral criteria of optometrists within New Zealand to investigate the diagnosis and management of keratoconus. METHODS: Optometrists recruited through the New Zealand Association of Optometrists, Cornea and Contact Lens Society of New Zealand, and private practices were invited to complete an anonymous survey. RESULTS: Responses were received from 168 optometrists (representing 20.0% of the optometrist population). Half (48%) of optometrists had ≥15 years of experience, and 22% prescribed soft contact lenses daily, whereas only 6.4% prescribed rigid gas-permeable (RGP) lenses daily. The main barriers to prescribing RGPs were experience with fitting, low market demand, and patient discomfort. When referring to an ophthalmologist, 41% reported referring on progression of corneal parameters, 27% on initial diagnosis, 21% at no set time, and 10% with a reduction in visual acuity. Most optometrists (64%) would refer for possible surgery when visual acuity dropped between 6/9 and 6/12. Optometrists with greater experience were more likely to prescribe RGP lenses and co-manage patients with ophthalmologists. Ownership of a corneal imaging unit suggested an increased likelihood of prescribing RGP lenses but did not alter referral patterns. CONCLUSION: This survey provides an overview of current practice and highlights the importance of optometrists in the diagnosis and management of keratoconus. There was a significant discrepancy in keratoconus management, regarding optical correction modality and referral criteria for ophthalmology review. Further interdisciplinary work is required between optometry and ophthalmology to standardize referral guidelines and enhance visual outcomes.

Navigating Coronavirus Disease 2019 Vaccination and Uveitis: Identifying the Rates and Risk of Recurrent Uveitis after Coronavirus Disease Vaccination.

PURPOSE: To identify rates of uveitis reactivation both before and after the coronavirus disease (COVID) 2019 vaccine in subjects with a previous diagnosis of uveitis. DESIGN: Retrospective study. PARTICIPANTS: Subjects were identified from the Inflammatory Eye Disease Registry at Auckland District Health Board diagnosed with uveitis between January 1, 2010, and December 31, 2020. METHODS: Date of COVID vaccination was determined from the patient clinical record. Rate of flare was calculated for 3 months before vaccination and 3 months after each vaccination. MAIN OUTCOME MEASURE: Uveitis flare was defined as the presence of new uveitis activity or increased activity that required a change in uveitis treatment. RESULTS: A total of 4184 eyes of 3008 patients were included in the study with a total of 8474 vaccinations given during the study period. Median age was 54.8 years, and 1474 (49.0%) were female. Noninfectious etiology was most common, occurring in 2296 patients (76.3%) and infectious etiology occurring in 712 patients (23.7%). Rate of uveitis flare was 12.3 per 1000 patient-months at baseline, 20.7 after the first dose, 15.0 after the second dose, 12.8 after the third dose, and 23.9 after the fourth dose. The median period of quiescence before flare was 3.9 years. An increase in uveitis flare was seen in both infectious uveitis (baseline 13.1 compared with 20.2 after first dose, 154% increase) and noninfectious uveitis (baseline 12.4 compared with 20.9 after first dose, 169% increase). Risk factors for uveitis flare were identified to be recurrent uveitis, chronic uveitis, shorter period of quiescence, and first dose of vaccine. Median time to uveitis flare was 0.53 months after the first vaccination, 1.74 months after the second vaccination, and 1.35 months after the third vaccination. CONCLUSIONS: The current study demonstrates an increased risk of uveitis flare after the first dose of COVID vaccination. This risk was highest in those with previous recurrences, chronic uveitis, and shorter period of quiescence. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Case Series: Different Presentations of Iris Melanoma-Potential Masquerade of Benign and Malignant.

SIGNIFICANCE: Iris melanoma and iris nevi can be challenging to distinguish clinically. This case series provides unique insight into the rare condition and variable clinical presentations of iris melanoma. PURPOSE: This study aimed to highlight the varying clinical presentations of iris melanoma and to demonstrate the overlapping features of melanoma and nevi. CASE REPORTS: This case series includes five patients of varying age and sex who presented to clinic with pigmented iris lesions. These five patients have differing timeline to presentation and very different clinical presentations of their lesions. Clinical evaluation was based around the established "ABDCEF" guide for the assessment of malignant risk in iris lesions. The presentation of each lesion is discussed in relation to this guide and the experienced clinician's clinical suspicion of malignancy. When comparing the clinical suspicion with histological analysis, after biopsy, the result may be unexpected. Notably, initially benign nevi may transform into melanoma over time. These five cases were managed on an individual basis because the management and prognosis of iris melanomas vary significantly. Importantly, iris melanotic lesions have variable metastatic risk based on cytology and genetic predisposition. Informed consent was obtained from all the patients, institutional approval was obtained, and no identifiable health information is included in this case series. CONCLUSIONS: When presented with a pigmented iris lesion, clinicians must be vigilant with regular monitoring and have a low threshold for biopsy in pigmented lesions of high clinical suspicion.

Endocapsular artificial iris implantation for iris defects: Reducing symptoms, restoring visual function and improving cosmesis.

BACKGROUND: To investigate repair of iris defects by endocapsular implantation of an artificial iris, in relation to visual outcomes, safety profile and patient satisfaction. METHODS: Retrospective, consecutive case series from Greenlane tertiary teaching hospital and Eye Institute, Auckland, New Zealand. Medical records of patients implanted with an endocapsular artificial iris were reviewed and followed for minimum 3 months. Patient characteristics, surgical management, clinical outcomes and subjective responses were recorded. RESULTS: Nineteen artificial irises were implanted in 18 patients. Etiologies were iris melanotic lesion excision (73.7%), trauma (10.5%), congenital aniridia (10.5%) and Urrets-Zavalia syndrome (5.3%). During postoperative follow-up [14.1 ± 12.4 months (range: 3 to 59 months)], best corrected visual acuity (BCVA) and intraocular pressure (IOP) did not change significantly [BCVA, 0.23 logarithm of the minimum angle of resolution (logMAR) (20/32 Snellen) preoperatively vs. 0.18 logMAR postoperatively (20/25 Snellen) (Z = -0.222, p = 0.824); IOP, 15 mmHg preoperatively vs. 17 mmHg postoperatively (Z = 1.377, p = 0.1447)]. Mild or self-limiting complications included: elevated IOP (42.1%), cystoid macular oedema (15.8%); persisting postoperative uveitis (15.8%) and minor vaulting of the prosthesis (15.7%). Moderate or severe complications included significant vaulting of prosthesis requiring surgical revision (5.3%) and a single eye (5.3%) with trabeculectomy and corneal graft failure. 94.4% of patients were very satisfied with the cosmesis and would be highly likely to have the procedure again. CONCLUSIONS: This study confirms that endocapsular insertion of an artificial iris is typically associated with good functional and cosmetic results and a relatively low risk of significant complications.

Integration and remodelling of a collagen anterior lamellar keratoplasty graft in an animal model - A preliminary report.

There is an international shortage of donor corneas for transplantation to treat the 1.5-2.0 million new cases of blindness secondary to corneal disease. Research has therefore been directed towards the development of artificial corneas using alternative materials such as collagen. The biocompatibility of an acellular collagen-based scaffold for anterior lamellar keratoplasty was investigated in vivo in a rabbit model. This scaffold has previously shown promise as a corneal substitute in vitro. Slit-lamp and Optical Coherence Tomography examinations were carried out at 2 weeks, 1, 2, 3, and 6 months post-operatively. Graft-host integration was investigated using immunohistochemistry of the cornea at 6 months. Results showed that the graft was biocompatible, supported corneal re-epithelialisation, and showed no signs of rejection. Migration of stromal cells into areas of the graft was observed, however this was accompanied by extensive graft digestion. Whilst the scaffold was biocompatible, further modifications to the material or supplementation with matrix metalloproteinase inhibitors are required to bring us closer to a stable and fully integrated corneal substitute.

Megalocornea, anterior megalophthalmos, keratoglobus and associated anterior segment disorders: A review.

Megalocornea and anterior megalophthalmos (megalocornea spectrum) disorders are typically defined by corneal diameter > 12.5 mm in the absence of elevated intraocular pressure. Clinical features overlap with keratoglobus but are distinct from buphthalmos and severe (globus) keratoconus. Megalocornea spectrum disorders and keratoglobus are primarily congenital disorders, often with syndromic associations; both can present with large and thin corneas, creating difficulty in diagnosis, however, only keratoglobus is typically progressive. Molecular genetics provide significant insight into underlying aetiologies. Nonetheless, careful clinical assessment remains intrinsic to diagnosis. Surgical management can be challenging due to the enlarged ciliary ring and weakened zonules in megalocornea spectrum disorders and the extreme corneal thinning of keratoglobus. In this review, the established literature on measurement of corneal diameter, diagnosis of megalocornea, anterior megalophthalmos and keratoglobus, differentiation from severe keratoconus, recent molecular genetics research and key surgical modalities in the management of these rare disorders are outlined and discussed.

Five-year results of a prospective, randomised, contralateral eye trial of corneal crosslinking for keratoconus.

BACKGROUND: Few studies have evaluated corneal crosslinking (CXL) in a prospective, randomised fashion. This study aimed to determine the efficacy and safety of CXL to reduce the progression of keratoconus. METHODS: Prospective, unmasked, randomised, contralateral eye controlled trial at a tertiary eye centre. PARTICIPANTS: Individuals with bilateral progressive keratoconus. One eye from each subject was randomised to CXL and the contralateral, untreated eye acted as the control. PRIMARY OUTCOME MEASURE: change in maximum keratometry. SECONDARY OUTCOME MEASURES: uncorrected distance visual acuity, spectacle corrected distance visual acuity, spherical equivalent refraction, simulated keratometry, corneal astigmatism, minimum pachymetry and complications. RESULTS: Thirty-eight individuals (mean age 21.1 ± 6.7 years) were enrolled with one eye treated with CXL. At 5 years, there was a mean decrease in maximum keratometry of treated eyes (-1.45 ± 2.25 D) compared to an increase among the controls (1.71 ± 2.46 D; p < 0.001). There were significant differences between the treated and control groups in the mean change of Steep SimK (-1.07 ± 1.22 vs. 0.96 ± 1.97 D; p < 0.001), Flat SimK (-0.61 ± 1.34 vs. 0.43 ± 1.12 D; p < 0.001), corneal astigmatism (-0.45 ± 1.31 vs. 0.63 ± 1.52 D; p < 0.01) and minimum pachymetry (-32.49 ± 26.32 vs. -13.57 ± 24.11 µm; p < 0.01). Complications included sterile infiltrates (n = 2), microbial keratitis (n = 1), persistent corneal haze/scarring at 5 years (n = 4) and loss of ≥2 lines of corrected distance visual acuity (n = 3). CONCLUSIONS: CXL is an effective and relatively safe intervention to halt or reduce the progression of keratoconus in the majority of eyes for at least 5 years.

Ocular complications and mortality in peripheral ulcerative keratitis and necrotising scleritis: The role of systemic immunosuppression.

IMPORTANCE: Inflammatory ocular diseases are associated with systemic disease, ocular morbidity and mortality. BACKGROUND: To examine clinical characteristics of subjects with peripheral ulcerative keratitis (PUK) and necrotising scleritis. DESIGN: Retrospective case series in a single tertiary centre over 10 years. PARTICIPANTS: All patients presenting with necrotising scleritis, PUK or scleritis with corneal infiltrates. Fifty-two eyes (41 subjects) were identified. METHODS: Demographic and clinical data analysis. MAIN OUTCOME MEASURES: Visual loss, ocular complications and mortality. RESULTS: Mean follow up was 7.0 ± 5.3 years, presentation age 51.3 ± 18.6 years, and 23 subjects (56.1%) were female. Overall, 27 eyes presented with PUK, 26 with necrotising scleritis, and 22 with corneal infiltrates associated with active scleritis. Associated systemic diagnosis was observed in 12 subjects at presentation, and in 21 subjects (51.2%) by final follow up. Recurrence occurred in 23 eyes (44.2%): 10 eyes experiencing PUK or necrotising scleritis; 13 eyes with non-necrotising scleritis. Perforation occurred in six eyes (11.5%). Moderate vision loss occurred in 10 eyes (19.2%) and severe loss in six eyes (11.5%). Five subjects (12.2%) were deceased by study conclusion, of whom four were not on immunomodulatory therapy (IMT). A marked difference in estimated survival was observed with IMT, with mean estimated survival of 10.7 years without treatment, compared to 24.7 years with IMT (P = .045). CONCLUSIONS AND RELEVANCE: PUK and necrotising scleritis represent a severe inflammatory disease with high rates of perforation, visual loss and mortality. IMT was associated with a lower rate of mortality and longer estimated survival in this group.

Successful culture of human transition zone cells.

BACKGROUND: Human corneal endothelial cells undergo very little or no proliferation and respond to cell loss by migration and cellular enlargement. Significant cell loss or damage may result in corneal oedema, opacity and loss of vision. In vitro expansion of corneal endothelial cells (CECs) is a promising strategy for corneal regeneration. The transition zone (TZ) may be an alternative source of CECs. The objective of this study was to establish a protocol for TZ cell culture, and to determine their potential to proliferate and differentiate into cells that resemble CECs in vitro. METHODS: An explant culture protocol for the human TZ was established. Cell proliferation was assessed using 5-ethynyl-2'-deoxyuridine (EdU) assay. The expression of stem cell and endothelial markers was assessed using immunohistochemistry and quantitative polymerase chain reaction. RESULTS: TZ cells can be passaged up to 12 times; cells became polygonal 3 to 4 passages before senescence. An average of 41% of cells incorporated EdU over a 5-day period. TZ cells expressed the corneal endothelial proteins ZO-1 and Na+ /K+ ATPase, Col8A2, the periocular mesenchyme marker PITX2, and the neural crest stem cell markers Nestin and Sox10. TZ cells expressed mRNA of a range of neural crest, periocular mesenchyme, and corneal endothelial genes. CONCLUSIONS: TZ cells can proliferate and differentiate into cells that resemble CECs, demonstrating their potential to be an alternative cell source for corneal endothelial cell therapy.

Enhancing Maori and Pasifika graduate interest in ophthalmology surgical training in New Zealand/Aotearoa: Barriers and opportunities.

IMPORTANCE: Improving the representation of indigenous ophthalmologists in New Zealand. BACKGROUND: Maori, indigenous to New Zealand/Aotearoa and Pacific Peoples indigenous to Pacific Island Nations living in New Zealand, experience poorer health outcomes across several ophthalmic conditions. The Royal Australian and New Zealand College of Ophthalmologists have identified indigenous workforce development as a priority. DESIGN: Mixed-methods study, utilizing retrospective analysis of Medical Schools Outcomes Database and Longitudinal Tracking Project responses, and prospective interviews with Maori/Pasifika medical graduates. PARTICIPANTS: This study involved 64 medical graduates from the University of Auckland (UoA) and the University of Otago, and six Maori/Pasifika medical postgraduates in New Zealand. METHODS: Retrospective analysis of medical graduate responses who ranked ophthalmology among their top-three preferred specialties in the Medical Schools Outcomes Database and Longitudinal Tracking Project. Prospective semi-structured interviews with Maori/Pasifika medical postgraduates. MAIN OUTCOME MEASURES: Specialty training influencing factors and prevocational ophthalmology experience. RESULTS: A total of 64 (6.7%) out of 954 medical graduates from the UoA and University of Otago ranked ophthalmology among their top-three preferred training specialties (2012-2017). Of the 64 graduates, six (9.3%) identified as Maori/Pasifika. No significant difference in influencing factors between Maori/Pasifika and non-Maori/Pasifika students was identified. Both groups ranked intellectual content, procedural skills, specialty exposure and mentorship as highly influential. Qualitative interviews with Maori/Pasifika graduates highlighted positive experiences in ophthalmology but limited exposure overall. Negative anecdotes and unclear training pathways discouraged Maori/Pasifika interest in Ophthalmology training. CONCLUSIONS AND RELEVANCE: Maori/Pasifika graduate interest in ophthalmology training was relatively low. Valuable insights include enhancing specialty exposure, mentor development, promoting Maori/Pasifika connections and clarifying training pathways for future graduates.

Auckland Cataract Study IV: Practical application of NZCRS cataract risk stratification to reduce phacoemulsification complications.

IMPORTANCE: Reduction of intraoperative complications in phacoemulsification cataract surgery. BACKGROUND: To assess practicability of a risk stratification system, the New Zealand Cataract Risk Stratification (NZCRS) system, in a major teaching hospital service, without investigator oversight, to ascertain whether benefits identified in research studies are maintained in busy clinical practice. DESIGN: Prospective cohort study in a major public teaching hospital. PARTICIPANTS: Five hundred cases of phacoemulsification cataract surgery. METHODS: NZCRS system inserted into 621 consecutive preoperative cataract patient files. Recommendation to allocate higher-risk cases to experienced surgeons. MAIN OUTCOME MEASURES: NZCRS system uptake and adherence, appropriate identification of high risk cases and intraoperative complication rates. RESULTS: NZCRS scores calculated in 500 of 621 (80.5%) cases and 98 (19.6%) scored as "high risk." Cataract surgery (N = 500) performed by: 12 Registrars (20%), 4 Fellows (7.2%), 26 Consultants (72.8%). Risk scores adhered to in 99%. Overall intraoperative complications (3.0%) included iris prolapse 1.6% and posterior capsule tear 0.8%. No statistical difference in complication rates identified between surgeon grades. Mean best-corrected visual acuity was 6/10 (20/32). Postoperatively, cystoid macular oedema occurred in 3.2%. Rescoring by an experienced investigator noted a greater number of "high risk scores" (31.6% vs 19.6%) related to differences in subjective scoring of anterior chamber depth and cataract density. CONCLUSIONS AND RELEVANCE: Practical uptake of cataract risk stratification was promising in this study with NZCRS calculated in 80.5% with 99% adherence to scoring recommendations. Compared to baseline studies, in the day-to-day clinical setting, a continued, decreasing trend in frequency and severity of intraoperative complications was noted. Subjective variability of risk scoring may be further improved by better, objective, standardization.

Comparison of corneal biomechanical properties following penetrating keratoplasty and deep anterior lamellar keratoplasty for keratoconus.

IMPORTANCE: Keratoplasty is a surgical procedure to create a more regular optical surface following biomechanical weakening of the cornea in keratoconus. The ideal keratoplasty procedure should also restore corneal biomechanics to that of the healthy cornea. BACKGROUND: This study aimed to evaluate and compare the biomechanical properties of corneas following penetrating keratoplasty (PKP) and predescematic deep anterior lamellar keratoplasty (DALK) to those of healthy eyes. DESIGN: Prospective cross-sectional study. PARTICIPANTS: Two cohorts of post-keratoplasty eyes (42 eyes with PKP and 27 eyes with DALK) with each other, and with a cohort of 152 healthy eyes. METHODS: All eyes were examined by slit-lamp biomicroscopy, tomography, anterior segment-OCT and non-contact tonometry CorVis ST (CST). MAIN OUTCOME MEASURES: CST biomechanical parameters, maximum corneal deformation (MCD) and corneal energy dissipation were compared between keratoplasty techniques, and with healthy eyes. RESULTS: The mean age of participants with PKP and DALK were 35 ± 13.7 and 36.1 ± 12.6 years, respectively. None of the CST parameters were significantly different between PKP and DALK eyes. However, when compared to healthy corneas, numerous parameters were significantly different for both keratoplasty techniques. Of note, MCD was significantly higher in PKP compared to DALK and healthy corneas, after controlling for co-factors. CONCLUSIONS AND RELEVANCE: Neither type of keratoplasty technique utilized in keratoconus completely restored corneal biomechanical properties to that of healthy corneas. However, PKP resulted in a greater number of parameters significantly different to healthy corneas, compared to DALK.

Topographic screening reveals keratoconus to be extremely common in Down syndrome.

IMPORTANCE: Keratoconus disproportionately affects people with Down syndrome (DS). This is the first study of its kind in Australasia. BACKGROUND: To investigate the prevalence of keratoconus in DS. DESIGN: Cross-sectional study. PARTICIPANTS: Athletes with DS attending 2017 New Zealand Special Olympics National Summer Games. METHODS: Keratoconus was identified using corneal topography (TMS-4N, Tomey). Topography from both eyes was required to be included. Two independent quantitative criteria were used to indicate keratoconus. The first was keratoconus severity index ≥ 30%. The second, adapted from the literature, required at least four of eight topographic parameters to be abnormal. Data from the worse eye were analysed. Diagnosis in each group was subsequently confirmed qualitatively by three corneal fellowship-trained ophthalmologists. Those with a definitive diagnosis were grouped into Keratoconus Confirmed Group 1 (KCC1) and Keratoconus Confirmed Group 2 (KCC2), respectively. MAIN OUTCOME MEASURES: Keratoconus prevalence, severity, demographics. RESULTS: Of 110 athletes screened, N = 98 were included, mean age 30.0 ± 9.7 years. Using only topographic data, keratoconus was identified in 39 (39.8%) athletes by quantitative topographic criteria 1, and in 63 (64.3%) athletes by criteria 2. Keratoconus was confirmed by qualitative sub-specialist review in 30 (30.6%) (KCC1) and 38 (38.8%) (KCC2) athletes, respectively. Mean keratometry in groups KCC1 and KCC2 were 48.4 ± 3.2D and 48.2 ± 2.9D, respectively. Most were male (KCC1 63.3%, KCC2 76.3%) and of European ethnicity (KCC1 80%, KCC2 78.9%). CONCLUSIONS AND RELEVANCE: We report keratoconus in 30.6% to 38.8% of athletes with DS; therefore, we believe keratoconus screening is indicated in DS for early management.

Microdroplet and spatter contamination during phacoemulsification cataract surgery in the era of COVID-19.

IMPORTANCE: Determine phacoemulsification cataract surgery risk in a Covid-19 era. BACKGROUND: SARS-CoV-2 (Covid-19) transmission via microdroplet and aerosol-generating procedures presents risk to medical professionals. As the most common elective surgical procedure performed globally; determining contamination risk from phacoemulsification cataract surgery may guide personal protection equipment use. DESIGN: Pilot study involving phacoemulsification cataract surgery on enucleated porcine eyes by experienced ophthalmologists in an ophthalmic operating theatre. PARTICIPANTS: Two ophthalmic surgical teams. METHODS: Standardized phacoemulsification of porcine eyes by two ophthalmologists accompanied by an assistant. Fluorescein incorporated into phacoemulsification irrigation fluid identifying microdroplets and spatter. Contamination documented using a single-lens reflex camera with a 532 nm narrow bandpass (fluorescein) filter, in-conjunction with a wide-field blue light and flat horizontal laser beam (wavelength 532 nm). Quantitative image analysis using Image-J software. MAIN OUTCOME MEASURES: Microdroplet and spatter contamination from cataract phacoemulsification. RESULTS: With phacoemulsification instruments fully within the eye, spatter contamination was limited to <10 cm. Insertion and removal of the phacoemulsification needle and bimanual irrigation/aspiration, with irrigation active generated spatter on the surgeons' gloves and gown extending to >16 cm below the neckline in surgeon 1 and > 5.5 cm below the neckline of surgeon 2. A small tear in the phacoemulsification irrigation sleeve, presented a worse-case scenario the greatest spatter. No contamination above the surgeons' neckline nor contamination of assistant occurred. CONCLUSIONS AND RELEVANCE: Cataract phacoemulsification generates microdroplets and spatter. Until further studies on SARS-CoV-2 transmission via microdroplets or aerosolisation of ocular fluid are reported, this pilot study only supports standard personal protective equipment.

Causes of childhood low vision and blindness in New Zealand.

IMPORTANCE: This is the first national study on childhood visual impairment in a developed nation, New Zealand, describing prevalence, aetiology and preventable causes of low vision and blindness in children. BACKGROUND: Causes of childhood blindness vary between regions. This study aimed to present region-specific data on epidemiology of childhood blindness affecting a developed nation, New Zealand. DESIGN: Retrospective data analysis. PARTICIPANTS: All children enrolled with the Blind and Low Vision Education Network New Zealand (BLENNZ) with best-corrected visual acuity ≤6/18, or binocular visual field <10°. METHODS: 1000 out of 1321 children with visual impairment enrolled with BLENNZ were included. The principal cause of visual loss was determined, and the severity of visual loss categorized as low vision, or blindness according to the World Health Organization criteria. MAIN OUTCOME MEASURES: Main outcome measures were degree of visual impairment, aetiology of visual impairment and treatment modalities for visual rehabilitation. RESULTS: The calculated prevalence of childhood blindness and low vision was 0.05% and 0.06%. Principle causes of blindness were cortical visual impairment (31.5%), optic nerve atrophy (16.5%) and optic nerve hypoplasia (9.0%). The main preventable causes of blindness were neonatal trauma/asphyxia (31.5%), retinopathy of prematurity (18.2%) and non-accidental injury (10.3%). CONCLUSIONS AND RELEVANCE: This is the first national report on prevalence of childhood low vision and blindness in New Zealand. The prevalence and leading causes of low vision and blindness found in this study were comparable to other developed nations; however, preventable causes of low vision and blindness appeared unique to New Zealand.

Visual and ocular morbidity in severe open-globe injuries presenting to a regional eye centre in New Zealand.

IMPORTANCE: Open-globe injuries (OGI) are a leading cause of monocular blindness world-wide with considerable cost to the individual and society. BACKGROUND: To characterize the epidemiology, severity and outcomes of OGI treated at a major ophthalmology centre in New Zealand. DESIGN: Retrospective study. PARTICIPANTS: A total of 385 eyes of 381 patients over a 10-year period. METHODS: Eligible patients were identified using diagnosis and surgery codes on hospital discharge summaries. Clinical notes were reviewed to determine patient demographics, injury details, treatments and outcomes. MAIN OUTCOME MEASURES: Complications of injury, visual acuity at 3 months and final follow-up, and final status of the eye. RESULTS: The estimated annual incidence of OGI was 2.8 per 100 000. Working-age males predominated but age at injury ranged from 9 months to 90 years. Maori and Pacific peoples were over-represented. Injuries were severe with 58.7% presenting with vision of hand movements or worse. Penetrating injuries (56.4%) were most common, followed by globe ruptures (35.6%). Major complications included retinal detachment (15.8%), enucleation/evisceration (9.1%), phthisis bulbi (9.9%), endophthalmitis (2.6%) and sympathetic ophthalmia (0.26%). Despite the injury severity, 46% of eyes achieved final BCVA of ≥6/12. The Ocular Trauma Score (OTS) was a useful prognostic tool for stratifying severity of injury and predicting visual outcome (Fisher's exact test P < 0.001). CONCLUSIONS AND RELEVANCE: The incidence and severity of OGI in NZ are comparable to global statistics. Surgical repair can effectively recover vision, predicted well by the OTS. We identified at-risk groups to target with education and prevention strategies.

Auckland regional telemedicine retinopathy of prematurity screening network: A 10-year review.

IMPORTANCE: Retinopathy of prematurity (ROP) is a potentially blinding condition affecting the retinae of premature infants. Effective screening is necessary for timely treatment. BACKGROUND: The Auckland Regional Telemedicine ROP (ART-ROP) network, utilizes wide-field digital imaging for ROP screening. This study reviews the ART-ROP network. DESIGN: Retrospective analysis of the ART-ROP database. PARTICIPANTS: Files of infants in ART-ROP from 2006 to 2015. METHODS: Data on infant demographics, ROP stage, treatment and outcome was collected. MAIN OUTCOME MEASURES: The efficacy of ART-ROP in the management of ROP. RESULTS: A review of 1181 infants across three neonatal intensive care units, was completed. Infants had a mean of four screening sessions with no infants who met ROP screening criteria being missed. Type 1 ROP was present in 83 infants, who had significantly lower average birth weight 786 ± 191 g compared to 1077 ± 285 g (P < .001), and gestational age 25.3 ± 1.7 weeks compared to 27.8 ± 2.2 weeks (P < .001) than the screened cohort. The number of infants requiring screening increased (R2 = .7993), yet treatment rates decreased (R2 = .9205) across the time period. Out-patient clinic follow-up was attended by 75.10% of infants screened and there was no missed ROP in those infants seen. CONCLUSIONS AND RELEVANCE: ART-ROP solely uses wide-field digital imaging for ROP diagnosis, and management, including discharge, of infants. This detailed review of ART-ROP indicates an increase in screening demand, but a decrease in the rate of type 1 ROP. The ART-ROP telemedicine model demonstrates real potential to address workforce shortage in ROP screening.