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A general shipboard power system contains multiple electrical machine sets to provide electrical power with different ratings for both the propulsion system and the ship service. In order to achieve the most compact design and maximize the weight reduction, a study of using a single dual wound generator to replace the electrical machine sets is presented in this paper. It consists of dual two-layer windings of different pole numbers which use the same slots and share one prime mover, producing two independent power supplies. This paper verifies a dual wound machine designed for no electromagnetic coupling by algebraically analyzing the spatial harmonic magnetic field distribution. Further verification of the absence of electromagnetic coupling due to both the airgap and slot leakage fluxes is provided by 2D finite element modeling. The dual wound generator prototype using the principle is designed, built and experimentally tested. The experimental results match well with the simulation results, validating the independence of the two power outputs and showing that the winding end-turns also do not couple. The results are significant for applications where multiple independent power supplies are needed, or where an auxiliary power supply is needed which could be drawn from an existing traction motor.

Corneal perforation is a clinical emergency that can result in blindness. Currently corneal perforations are treated either by cyanoacrylate glue which is toxic to corneal cells, or by using commercial fibrin glue for small perforations. Both methods use manual delivery which lead to uncontrolled application of the glues to the corneal surface. Therefore, there is a need to develop a safe and effective alternative to artificial adhesives.Previously, our group developed a transparent human platelet lysate (hPL)-based biomaterial that accelerated corneal epithelial cells healing in vitro. This biomaterial was further characterized in this study using rheometry and adhesive test, and a two-component delivery system was developed for its application. An animal trial (5 New Zealand white rabbits) to compare impact of the biomaterial and cyanoacrylate glue (control group) on a 2 mm perforation was conducted to evaluate safety and efficacy.The hPL-based biomaterial showed higher adhesiveness compared to commercial fibrin glue. Treatment rabbits had lower pain scores and faster recovery, despite generating similar scar-forming structure compared to controls. No secondary corneal ulcer was generated in rabbits treated with the bio-adhesive.This study reports an in situ printing system capable of delivering a hPL-based, transparent bio-adhesive and successfully treating small corneal perforations. The bio-adhesive-treated rabbits recovered faster and required no additional analgesia.The developed in situ hPL bio-adhesives treatment represents a new format of treating corneal perforation that is easy to use, allows for accurate application, and can be a potentially effective and pain relief treatment.

Femtosecond laser-assisted cataract surgery (FLACS) was introduced with the hope of making cataract surgery safer and making the refractive result more predictable. It is only in the last four years that level 1 prospective randomised controlled trials (RCT) using current technology have been published. These, along with a meta-analysis of recent studies have shown that there seems to be little long-term visual benefit when using FLACS with monofocal lenses. The promised decrease in ultrasound energy required to remove a cataract has not been consistently demonstrated. There is level one evidence that the rate of posterior capsular rupture is less with FLACS using modern software. The round capsulotomy may be of increasing importance with the uptake of toric, multifocal and extended depth of focus lenses where a predictable capsulotomy size and precise placement of the lens becomes more important., Video abstract Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use: https://youtu.be/nCS4ub-OBUc

Human platelet products have emerged as an alternative treatment for a range of ocular surface diseases such as dry eye and corneal ulceration. With significant therapeutic potential and increasing popularity, this study aimed to conduct a systematic review to detail the various production methods involved in generating platelet-derived products, compare and analyze clinical findings across available studies, and disseminate the relative advantages, limitations, and challenges of using platelet products to treat ocular surface disease. Thirty-eight clinical studies were identified, excluding studies conducted in animals and non-English language. Studies reported clinical outcomes, which included ocular surface disease index, best-corrected visual acuity, and corneal fluorescein staining. Most clinical studies reported improved patient signs and symptoms with an increasing variety of human platelet products including platelet rich plasma eye drops, human platelet lysate and platelet gels. However, due to variations in production methods, and study designs as well as confusing terminology, it was suggested that characterization of platelet products is needed for proper evaluation across studies.

Mariska Ackerman,1 Michael Lawless,2,3 Lewis Levitz,4 Uday Bhatt,4 Joseph A Reich,4 Gerard Sutton,2,3 Timothy V Roberts,2,3 Abi Tenen,4 Amanpreet Kaur,4 Chris Hodge2,3,5,6 1Sydney Medical School, The University of Sydney, Sydney, New South Wales, Australia; 2Vision Eye Institute, Sydney, New South Wales, Australia; 3Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia; 4Vision Eye Institute, Melbourne, Victoria, Australia; 5Graduate School of Health, University of Technology Sydney, Sydney, New South Wales, Australia; 6Macquarie University, Sydney, AustraliaCorrespondence: Michael Lawless, Vision Eye Institute, Level 3 270 Victoria Avenue, Chatswood, Sydney, NSW, 2067, Australia, Tel +61 2 9424 9999, Fax +61 2 9410 3000, Email michael.lawless@vei.com.auPurpose: Trifocal Intraocular Lenses (IOLs) were developed to provide patients with effective near, intermediate and distance vision, thus minimizing spectacle dependency. Residual astigmatism has previously been shown to impact unaided visual acuity across all distances; therefore, to optimise the expected outcomes, consideration of preoperative corneal astigmatism is essential. The purpose of this study was to provide a real-world, multi-site review of visual and refractive outcomes in eyes undergoing implantation with the Panoptix Trifocal toric IOL platform.Patients and Methods: This study represents a two-fold approach. Patients who had previously undergone routine cataract removal and IOL insertion with the Panoptix Toric IOL were retrospectively analysed for routine efficacy and safety endpoints (“Retrospective Cohort”). Data was retrieved from the preoperative, surgical and postoperative visits (range 2– 6 weeks). A further subset of patients undergoing lens removal and bilateral Panoptix Toric IOL insertion were identified at surgery (“Qualitative Cohort”). These patients underwent additional testing inclusive of quality of vision questionnaire and bilateral defocus curve.Results: A total of 466 eyes of 254 patients were included in the retrospective cohort. Between 91% and 98% of eyes, respectively, were within 0.50D and 1.00D of target. Mean absolute difference from Spherical Equivalent (SE) target was 0.22 ± 0.24Ds. Following surgery, 94% of eyes demonstrated a refractive astigmatism of 0.50D or less. Further, 61% eyes achieved uncorrected distance visual acuity (UDVA) of 20/20 or better, increasing to 94% achieving 20/32 or better. Seventy percent of eyes unilaterally achieved N5 unaided and 66.0% achieved N8 or better at intermediate. In the qualitative cohort, no patient described any symptom as significant or requested explant.Conclusion: In a real-world setting, the PanOptix toric trifocal IOL continues to demonstrate refractive accuracy and good visual performance at all focal distances. This IOL also exhibited good quality of vision, with minimally bothersome visual disturbances or photic phenomena.Keywords: cataract surgery, IOL, trifocal, lens extraction, visual acuity

Tissue Biobanks represent an invaluable resource. Despite the majority of people supporting tissue donation, the actual rate remains low overall. Tissue discarded from surgical procedures represents a further avenue for collection for use in research. We aim to understand the information and consent requirements in a cohort of healthy, post-ophthalmic surgical subjects to optimise future tissue collection in living donors. Patients attending an ophthalmic clinic following refractive surgery for myopia (SMILE) were identified. Patient consent was implied with the completion of the provided survey. The questionnaire included gender, age range and education status. The majority of 31 subjects identified a benefit for future patients as the main motive for potential donation of discarded tissue (71%). Payment for the discarded tissue would not influence their decision in 77.4%. Explanation of the potential benefits of research was the most important information to consider before making a decision to donate. Only 12.9% of patients would have refused to include further information. Almost half of patients felt that the Biobank became the owner of tissue following donation. Current surgical patients may be more inclined to participate in research than the general public because of a sense of duty or an increased understanding of the role of research in evolving treatment. Despite minor uncertainty about the eventual use of the tissue and data, most subjects were positive to donation of discarded ocular tissue and de-identified information. Consent and education processes should be revised within an ophthalmic practice to minimise future patient anxiety.

Importance Intraocular lens (IOL) calculations in post-refractive cases remain a concern. Our study identifies improved options for surgeons. Background To evaluate and compare the prediction accuracy of IOL power calculation methods after previous laser refractive surgery using standard keratometry (SK), measured posterior corneal astigmatism (PCA) and total keratometry (TK). Design Retrospective consecutive cohort. Participants A total of 50 consecutive patients (72 eyes) at a private institution who underwent cataract surgery with prior laser refractive procedures. Methods Methods using SK included ASCRS mean, Barrett True-K no history, Haigis-L and Shammas IOL formulae. Barrett True-K using posterior values (True K TK), Haigis and Holladay 1 Double-K methods using TK were also assessed. Post-surgery refraction was undertaken at minimum 3 weeks following surgery. Main outcome measures Arithmetic and absolute IOL refractive prediction errors, variances in mean arithmetic IOL prediction error, and percentage of eyes within ±0.25D, ±0.50D, ±0.75D and ±1.00D of refractive prediction errors were compared. Results The Barrett True-K (TK) provided the lowest mean refractive prediction error (RPE) and variance for both prior myopes and hyperopes undergoing cataract surgery. The Barrett True-K (TK) exhibited the highest percentages of eyes within ±0.50D, ±0.75D and ±1.00D of the RPE compared to other formulae for prior myopic patients. Conclusions and relevance Accuracy of IOL power calculations in post-laser eyes can be improved by the addition of posterior corneal values as measured by the IOLMaster 700. The use of total keratometry may supplement outcomes when no prior refraction history is known.

Purpose Simultaneous cataract and glaucoma surgery has traditionally been challenging for the anterior segment surgeon. The introduction of minimally invasive glaucoma surgery (MIGS) in conjunction with cataract surgery appears safe and effective in lowering intraocular pressure. Although a significant visual impact leading from the combined procedure is unexpected, we aim to describe the refractive outcomes in a cohort of patients undergoing simultaneous cataract removal and iStent inject and discuss the potential implications of combined surgery in patients with co-existent glaucoma. Patients and Methods This is a retrospective consecutive case series inclusive of patients undergoing combined femtosecond laser-assisted cataract surgery and the insertion of two trabecular micro-bypass stents (iStent inject). Visual acuity, refraction and astigmatic vector analysis were collated and analysed from the preoperative and 4 weeks postoperative visits. Results One hundred and six eyes of 89 patients from 2 surgeons were included in the original cohort. The mean absolute difference from target refraction was 0.36 ± 0.25D. 73.9% of eyes were within ± 0.5D of the refractive target and 98.9% of eyes were within ± 1.00D. 73.8% of eyes had 0.5D or less residual refractive astigmatism following the procedure. Conclusion We present a novel cohort of glaucoma patients undergoing combined trabecular micro-bypass stents (iStent inject) and cataract surgery achieving excellent refractive outcomes. The results of this study indicate that this second-generation device is refractively neutral.

Importance There is limited literature on the use of optical coherence tomography in the assessment of retinal nerve fibre layer (RNFL) thickness in sports-related repetitive mild traumatic brain injury. Background To evaluate RNFL thickness in professional rugby league players. RNFL thinning may serve as a proxy for wider white matter degeneration. Design Cross-sectional observational study. Participants Thirteen retired Australian professional rugby league players were recruited. Methods Participants underwent binocular optical coherence tomography to measure RNFL thickness. Each participant underwent a complete ophthalmic assessment to exclude concurrent disease. Main outcome measures RNFL thickness of each eye were compared with a normative database. Results Participants had played professional Rugby League for 18 years on average and reported sustaining 15 sports-related concussions throughout their career. The RNFL in participants was four micrometres thinner than that of matched normative data. Cohort average RNFL thickness was reduced in 12 out of 14 optical coherence testing parameters. These findings were statistically significant in the left inferonasal [P = .013] and left nasal [P = .006] sectors. There was no statistically significant relationship between RNFL thickness and other visual measures. Conclusions and relevance This study is the first to demonstrate RNFL thinning in a cohort of retired Australian professional Rugby League players. RNFL changes have been shown to correlate with cerebral white matter loss and neurodegeneration. Optical coherence tomography may serve as a safe and economical means of screening for repetitive traumatic brain injury related neurodegeneration in contact sport athletes.

This case report presents an atypical, late presentation of keratoconus in a geriatric patient with successful management using a transepithelial corneal crosslinking (CXL) procedure. The treatment-naive 77-year old patient presented to the clinic after an assessment by an optometrist for recent onset of reduced vision that was initially thought to represent early cataract development. Corneal topography confirmed keratoconus, and subsequent review identified further progression. Crosslinking was performed using a transepithelial approach. The patient was followed for 3 years postoperatively. By the final visit, the uncorrected distance visual acuity had improved and the corrected distance visual acuity remained at 20/20 bilaterally. Corneal topographic parameters were considered stable. This case shows that keratoconus can present outside the previously established parameters and that CXL might be an effective option in older patients showing signs of progression. This might have additional benefits for future intraocular lens power calculations.

PurposeCorneal perforation is a clinical emergency. Tissue glue to seal the perforation, and supplementary topical medication represents existing standard treatment. Previously, our group developed a transparent human platelet lysate (hPL)-based biomaterial that showed good cell compatibility and accelerated corneal epithelial cells healingin-vitro.This study aims to develop a novel treatment method for corneal perforation using this biomaterial.MethodsRheometry was used to measure the hPL-based biomaterial behaviour at room and corneal surface temperatures. Its adhesiveness to porcine skin and burst pressure limit were also measured. Based on rheological behaviour, a hand-held biopen was developed to extrude it onto the cornea. An animal trial (5 New Zealand white rabbits) to compare impact of the biomaterial and cyanoacrylate glue (control group) on a 2mm perforation was conducted to evaluate safety and efficacy.ResultsThe hPL-based biomaterial showed higher adhesiveness compared to commercial fibrin glue and withstood burst pressure approximately 6.4× higher than routine intraocular pressure. Treatment rabbits had lower pain scores and faster recovery, despite generating similar scar-forming structure compared to controls. No secondary corneal ulcer was generated in rabbits treated with the bio-adhesive.ConclusionsThis study reports a novelin-situprinting system capable of delivering a hPL-based, transparent bio-adhesive and successfully treating small corneal perforations. Bio-adhesive-treated rabbits recovered faster and required no additional analgesia. Both groups showed scarred corneal tissue after healing, however no infection and inflammation was observed by 3 weeks. The delivery system was easy to use and may represent an alternative treatment for corneal perforation.HighlightsThis study presents a novelin situprinting system to treat corneal perforationThe system is comprised of a human platelet lysate-based bio-adhesive and a pen-like hand held delivery systemMechanical tests showed our transparent bio-adhesive has a higher adhesiveness compared to existing treatments and burst pressure threshold approximately 6.4 times higher than normal intraocular pressure.In vivo rabbit trial showed that compared to cyanoacrylate glue, the bio-adhesive was safer, faster healing and led to less pain in rabbits.

PURPOSE: To present an analysis of tear film hyperosmolarity in a large, consecutive population and evaluate the correlation of ocular and systemic conditions with tear film osmolarity (TFO). SETTING: Private practice, Sydney, Australia. DESIGN: Single-center, retrospective, consecutive cohort. METHOD: Patients undergoing screening for laser refractive surgery from October 2017 to October 2020 were retrospectively reviewed. 1404 patients (n = 1357 standard, n = 47 postrefractive) undergoing screening for laser refractive surgery from October 2017 to October 2020 were reviewed. Routine examination included TFO and Ocular Surface Disease Index (OSDI) questionnaire. TFO was conducted prior to further tests, and patients refrained from topical eyedrops minimum 2 hours before the appointment. RESULTS: 1404 patients (n = 1357 standards, n = 47 postrefractive) patients were reviewed. Mean highest TFO in the standard population was 299.12 ± 11.94 mOsm/L, with 82.3% of eyes

In this chapter, we will explore access to human tissue for research and the role of the eye bank and biobank custodians responsible for this provision. We will examine the donation and allocation processes, discuss existing systems, donation and allocation pathways, the barriers to research allocation, and the ethical and the legal measures required to ensure that respect for the donation and the individual is maintained when providing tissue for research. Finally, we provide recommendations for researchers seeking human tissue for research.

Purpose: Corneal perforation is a clinical emergency. Tissue glue to seal the perforation, and supplementary topical medication represents existing standard treatment. Previously, our group developed a transparent bioink that showed good cell compatibility and accelerated corneal epithelial cells healing in-vitro. This study aims to develop a novel treatment method for corneal perforation using this bioink. Methods: Rheometry was used to measure bioink behaviour at room and corneal surface temperatures. Bioink adhesiveness to porcine skin and burst pressure limit were also measured. Based on rheological behaviour, a hand-held biopen was developed to extrude the bioink onto the cornea. An animal trial (5 New Zealand white rabbits) to compare bioink and cyanoacrylate glue (control group) impact on a 2mm perforation was conducted to evaluate safety and efficacy. Results: Bioink has higher adhesiveness compared to commercial fibrin glue and can withstand burst pressure approximately 6.4x higher than routine intraocular pressure. Bioink-treated rabbits had lower pain score and faster recovery, despite generating similar scar-forming structure after healing compared to controls. No secondary corneal ulcer was generated in rabbits treated with bioink. Conclusions: This study reports a novel in-situ printing system capable of delivering a transparent bioink to the cornea and successfully treating small corneal perforations. Bioink-treated rabbits recovered faster to completely healed perforation and required no additional analgesia. Both groups showed scarred corneal tissue after healing, however no infection and inflammation was observed 3 weeks. The delivery system was easy to use and may represent an alternative treatment for corneal perforation. Funding Information: We acknowledge the funding support from Australian Research Council (ARC) Centre of Excellence Scheme (CE140100012), Sydney Eye Hospital Foundation and NSW Medical Device Fund. The hPL used within the study was a gift from Australia Red Cross. Declaration of Interests: J. You (P), iFix Medical (I,F); H. Frazer (P); S. Sayyar, None; Z. Chen, None; X. Liu, None; A. Taylor, None; B. Filippi, None; S. Beirne, None; I. Wise, None; C. Hodge, None; G. Wallace, None; G. Sutton (P), iFix Medical (I). Ethics Approval Statement: Human corneas not meeting transplantation quality requirements were obtained from New South Wales Organ & Tissue Donation Service (Human Research Ethics Committee approval 14/275). The trial was conducted at the University of Sydney Charles Perkins Centre Laboratory Animal House Facility with Animal Ethics Committee approval (AEC: 2018/1317).

Nystagmus is an involuntary eye movement frequently associated with ocular co-morbidities including refractive error, amblyopia and strabismus.1 An abnormal head posture to dampen nystagmus express...

Purpose To develop a human platelet lysate (hPL)-based bioink that is transparent and also encompasses the regenerative properties of hPL to facilitate wound healing. Methods The effect of different batches of hPLand fetal bovine serum (FBS) on corneal epithelial cell growth and scratch assay was first examined using Incucyte Zoom. Various combinations of human fibrinogen (concentration range from 0.2 to 5 mg/mL) and thrombin (concentration from 1 to 10 U/mL) were combined with hPL to generate nine types of potential bioink. Rheology, transparency, and cell compatibility of bioinks were assessed and compared. The final selected bioink was used in an ex vivo corneal model to examine its ability in re-epithelization. Results No significant difference was detected in cell proliferation and wound healing tests between different hPL batches at the same concentration. Scratch assay data showed that hPL had significantly higher effect on wound healing than FBS. Comparing across the nine bioinks, bioink 5 consisting of 10% hPL, 2 mg/mL fibrinogen, and 5 U/mL thrombin demonstrated all required mechanical and cellular properties and was able to regenerate the full-thickness epithelium ex vivo. Conclusions The results showed that a transparent and adhesive bioink can be generated by combining hPL, fibrinogen, and thrombin together. The bioink can be directly applied to a human cornea to promote corneal re-epithelization with huge potential applications in corneal injuries. Translational relevance The developed transparent hPL-based ink with its adhesive and healing ability showed that it could be used as a new treatment option for corneal injuries.

The transparent cornea is the window of the eye, facilitating the entry of light rays and controlling focusing the movement of the light within the eye. The cornea is critical, contributing to 75% of the refractive power of the eye. Keratoconus is a progressive and multifactorial corneal degenerative disease affecting 1 in 2000 individuals worldwide. Currently, there is no cure for keratoconus other than corneal transplantation for advanced stage keratoconus or corneal cross-linking, which can only halt KC progression. The ability to accurately identify subtle KC or KC progression is of vital clinical significance. To date, there has been little consensus on a useful model to classify KC patients, which therefore inhibits the ability to predict disease progression accurately. In this paper, we utilised machine learning to analyse data from 124 KC patients, including topographical and clinical variables. Both supervised multilayer perceptron and unsupervised variational autoencoder models were used to classify KC patients with reference to the existing Amsler-Krumeich (A-K) classification system. Both methods result in high accuracy, with the unsupervised method showing better performance. The result showed that the unsupervised method with a selection of 29 variables could be a powerful tool to provide an automatic classification tool for clinicians. These outcomes provide a platform for additional analysis for the progression and treatment of keratoconus., 7 pages, 8 figures, 3 tables

Lewis Levitz,1 Joseph Reich,1 Chris Hodge1,2 1Vision Eye Institute Camberwell, Hawthorn East, VIC, Australia; 2Graduate School of Health, University of Technology Sydney, Sydney, NSW, Australia Purpose: The aim of the study was to determine whether femtosecond-assisted laser cataract surgery (FLACS) reduces the posterior capsular complication (PCC) rate compared to manual cataract surgery when performed by an experienced surgeon. Patients and methods: We reviewed 2,021 consecutive FLACS procedures between 1 June 2012 and 30 August 2017. All cases of posterior capsular rupture (PCR) with or without vitreous prolapse or zonular dialysis (ZD) that prevented an in-the-bag placement of the intraocular lens were included. Risk factors were noted and outcomes documented. Results: Six eyes of 2,021 (0.3%) who underwent FLACS had either a PCR or ZD. One eye (0.25%) of 403 eyes that had manual cataract surgery had a PCR. There was no significant difference in outcomes. Risk factors included advanced age, dense nuclei, pseudoexfoliation and small pupil. Only a single case in the FLACS series may have been directly attributed to the FLACS procedure. Conclusion: This study provides evidence that there is no significant difference in the PCC rate between FLACS and manual cataract surgery in the hand of an experienced surgeon who performs >350 cases annually. This low rate of complications may be achieved by less experienced surgeons adopting FLACS. Keywords: cataract surgery, phacoemulsification complications, femtosecond laser-assisted cataract surgery, safety, posterior capsule rupture, zonular dehiscence

Background: Laser-Assisted in situ Keratomileusis (LASIK) can induce corneal aberrations that can impact vision and patient satisfaction. Recent developments in laser technologies have helped minimise these aberrations. Objective: To assess the quality of vision and change in Higher-Order Aberrations (HOAs) following wavefront-optimized LASIK in low-myopic astigmatic patients. Methods: LASIK was performed on a total of 76 eyes in patients with myopia Results: Mean postoperative Spherical Equivalent (SE) was -0.09 ± 0.26 µm with 95% of patients within ± 0.5 D of attempted SE. Postoperative uncorrected distance visual acuity was 20/20 or better for 96% of patients. Contrast sensitivity increased against horizontal and vertical gratings at all spatial frequencies except for vertical gratings at 18 cycles/degree. Spherical aberration and total HOA increased by 0.085 µm and 0.13 µm respectively. The mean VF14 score increased from 89.2 ± 16.7% to 99 ± 1.4% postoperatively. Conclusion: LASIK performed using the WaveLight® EX500 excimer and WaveLight® FS200 laser platform provided improved contrast sensitivity and visual acuity with minimal introduction of HOAs, making it a suitable platform for low myopic astigmatic patients.

In the original version of this Article, a relevant paper on the detection of PLLP in human corneal epithelium during KC pathogenesis was not cited. This article is now cited as Ref 56 and discussed. As a result, in the Conclusion, "Notch1 and PLLP have not previously been linked to KC pathogenesis. PLLP has not been previously reported to be expressed in human corneal epithelium, although its roles in other tissues suggests it could play a critical role in normal corneal epithelial cellular activities, and interact with the Notch1 signaling pathway." now reads: "Notch1 has not previously been linked to KC pathogenesis. PLLP was reported to be upregulated in KC corneal epithelium compared to normal through proteomic analysis56. Both previous finding and our paper suggested an abnormal expression of PLLP in KC, however our study showed PLLP was down-regulated in KC. The difference can be attributed to the sample types and preparation. Myopia rather than normal corneal samples were used as control in this study. We measured and compared PLLP expression in each sample, whereas the previous study used pooled sample56 and therefore may mask the individual differences. The role of PLLP in human corneal epithelium is unclear, however findings from studies in other tissues suggest that it could be important in maintaining normal corneal epithelial cellular activities and interact with the Notch 1 signalling pathway." Subsequent references in the Article have been renumbered accordingly. The original Article has been corrected.

Importance This study represents a novel comparison of recently introduced intraocular lens power calculation formulas. Background To compare current new generation formulas for calculating the intraocular lens power for a standard cohort of patients undergoing cataract and lens replacement surgery in a private group practice in Australia. Design Retrospective case series comparison. Participants Postoperative results from 400 consecutive patients undergoing implantation of an SN60WF intraocular lens post cataract removal by 12 surgeons were used. Methods Refractive outcomes were compared with expected targets to determine the predicted refractive outcomes using the Hill-radial basis function, Barrett Universal II and readily available third or fourth generation intraocular lens power calculation formulas. Main Outcome Measure Mean absolute predicted error. Results The mean absolute predicted difference ranged from 0.30 to 0.34 D. There was no overall significant difference in the predicted difference or variance between formulas. All formulas achieved greater than 78.3% of eyes within ±0.5 D of intended refraction. The Hill-radial basis function and Barrett formulas provided the lowest mean numerical error compared with existing formulas in short and long eyes, respectively. The Barrett Universal II formula had the lowest percentage of refractive surprises (>1 D from predicted error) across all axial lengths. Conclusions and Relevance Acceptable outcomes can be achieved with optical biometry, consistent surgical technique and use of current intraocular lens power calculation formulas. The Barrett Universal II formula may provide the lowest risk of refractive surprise compared with other intraocular lens power calculation formulas.

Importance This study is the first paper to establish a learning curve by a single technician. Background Preparation of pre-cut corneal endothelial grafts commenced at Lions New South Wales Eye Bank in December 2014. The primary objective of this study was to review the safety and reliability of the preparation method during the first year of production. Design This is a hospital-based, prospective case series. Participants There were 234 consecutive donor corneal lenticules. Methods Donor lenticules were prepared by a single operator using a linear cutting microkeratome. Immediately prior to cutting, central corneal thickness values were recorded. Measurements of the corneal bed were taken immediately following lenticule preparation. Outcomes were separated by blade sizes, and intended thickness was compared to actual thickness for each setting. Early specimens were compared to later ones to assess for a learning curve within the technique. Main Outcome Measure The main parameter measured is the mean difference from intended lamellar cut thickness. Results The mean final cut thickness was 122.36 ± 20.35 μm, and the mean difference from intended cut was 30.17 ± 37.45 μm. No significant difference was found between results achieved with early specimens versus those achieved with later specimens (P = 0.425). Conclusions and Relevance Thin, reproducible endothelial grafts can routinely be produced by trained technicians at their respective eye banks without significant concerns for an extended learning curve. This service can reduce perioperative surgical complexity, required surgical paraphernalia and theatre times. The consistent preparation of single-pass, ultrathin pre-cut corneas may have additional advantages for surgeons seeking to introduce lamellar techniques.

Background Ocular dysfunction, including eye movement defects, has been documented in up to 69% of patients with concussion. However, standard sports-related concussion assessment protocols do not typically include any clinical examination of the ocular system. Objective The aim of this article is to inform general practitioners (GPs) about ocular defects associated with concussion, identify test procedures and highlight the important role of GPs within the concussion paradigm. Discussion Ocular dysfunction that commonly occurs with concussion includes abnormalities of accommodation, convergence, saccades and smooth pursuits. This may cause blurred vision, double vision, ocular pain and difficulty with close work. Symptoms can severely affect daily work, school or play activities. Patients complaining of extended ocular symptoms following concussion should be referred to an ophthalmologist for a complete ocular assessment.

© 2019 Wolters Kluwer Health, Inc. All rights reserved. Purpose:To report the rate of microbial contamination and analyze possible risk factors for contamination of banked corneas stored using the organ culture method.Methods:Data from the New South Wales Tissue Banks incorporating the Lions NSW Eye Bank, between September 1, 2011, and November 30, 2017, were reviewed retrospectively. All corneas collected during this period and stored in organ culture storage media were tested for microbial contamination. The influence of potential factors on the rate of contamination was analyzed using the χ2 test and logistic regression using generalized estimating equations.Results:A total of 4410 corneas were included in this study, of which 110 were medium culture positive, representing a microbial contamination rate of 2.5%. The main contaminants were Candida species followed by Staphylococcus species. Corneal tissue collected in summer and autumn had a significantly higher contamination rate (P = 0.006). All other factors studied were not shown to have a statistically significant association with contamination after accounting for within-pair correlation and confounders.Conclusions:A relatively low contamination rate of 2.5% observed in our study reflects the stringent laboratory protocols, strict donor selection criteria, and high level of experience among staff at the Lions NSW Eye Bank. Our study demonstrated that the season of collection had a strong association with the rate of organ culture contamination. Because Candida species contributed the largest percentage of contamination, specific measures to reduce and eliminate fungal proliferation should be considered by eye banks particularly in warm seasons.

Objectives: The recognition and management of concussion has become a major health concern across all sports. Despite recent attention, concussion assessment and return-to-play protocols appear to ...

Abnormalities of eye movement and visual processing are common in traumatic brain injury. The King-Devick test (KDT) has been widely used in the detection and recovery of concussion. Current recommendations propose performing the initial test at baseline and then repeating annually to account for potential learning effects. In practice, this may still account for large deviations. The aim of this study was to determine the number of trials needed for a player to achieve a ceiling effect and to determine the validity of the existing protocol requiring two tests at baseline.One hundred and eighty-three semi-professional male rugby union players (median age = 22.5 (21.0-25.3) years) were recruited. Over the duration, all athletes performed the KDT on an iPad, under standardised baseline procedures and then repeated the test based on availability during weekly in-season training.The improvement through each repeated trial was 0.60 ± 0.1 s (P 0.001). The ceiling effect was determined at 30 trials. A median difference of 4.2 s (range 0-14.9) was calculated between the initial and best trial overall, although the greatest difference occurred within the first eight attempts. There was a significant positive correlation between the initial test value and the difference between first and fastest time (P 0.001, r = 0.455).We have shown continuous improvement with repeated attempts which suggests that administrators ideally should continue to perform the KDT over the duration of the season to optimise the value of the test.

Organ Culture corneal storage offers an extended storage time and increased donor pool and tissue assessment opportunities. In September 2011, the Lions New South Wales Eye Bank (LNSWEB) moved from hypothermic storage to Organ Culture corneal storage. This study evaluates the impact of implementation of Organ Culture on donor eye retrieval and the corneal transplant waiting list over a 3 year period in NSW, Australia. Retrospective review of the LNSWEB data from September 2011 to August 2014. Tissue collection, waiting list and tissue utilization data were recorded. The data from September 2008 to August 2011 for Optisol-GS storage was used for comparison. The annual donor and cornea collection rate increased 35 % and 44 % respectively with Organ Culture compared to Optisol-GS storage. The utilization rate of corneal tissue increased from 73.4 % with hypothermic storage to 77.2 % with Organ Culture storage. The transplant wait list decreased by 77.3 % from September 2011 to August 2014 and correlated with the increased rate of corneal transplantation (r = −0.9381, p

Small incision lenticule extraction (SMILE) represents a recent addition to the refractive surgeon's range of procedures. Although there remains a number of similarities to existing techniques in terms of patient selection and treatment parameters, consideration is required to optimise patient outcomes and satisfaction. Here, we review the selection criteria, contraindications, indications and existing published safety and efficacy outcomes.

Background Keratometry is a critical determinant of the postoperative refractive outcome. This study evaluates the comparability of keratometry measurements obtained using the Verion Optical Imaging System with devices used in current clinical practice. Further, it determines the interobserver reliability of the Verion Optical Imaging System. Design Retrospective analysis of patient data Participants Keratometric data was obtained from 100 patients presenting for pre-operative evaluation. Furthermore, repeatability and reproducibility were assessed using 15 healthy volunteers. Methods Corneal curvature values acquired by the Verion Optical Imaging System were compared with existing keratometry devices including autokeratometry, partial coherence interferometry (IOLMaster) and Scheimpflug corneal topography (Pentacam). Main Outcome Measures Direct comparison of corneal power, cylinder, axis of astigmatism and vector analysis were performed using correlation and Bland–Altman analyses. Reproducibility and reliability of the device were assessed using within-subject standard deviation and intraclass correlation coefficients for experienced and inexperienced technicians. Results There was no statistically significant difference between Verion values and those obtained by other methods in relation to mean keratometry, corneal astigmatism, steep meridian and vector analyses (P > 0.05). Bland–Altman plots showed narrow limits of agreement for keratometry and astigmatism and wider agreement for steep meridian. Intraoperator reliability for both experienced and inexperienced operators and interoperator reproducibility showed no statistically significant differences between values. Conclusion Measurements show no significant difference from those obtained by the other devices. This suggests the Verion system is en par with instruments used in current clinical practice. The Verion Optical Imaging System produces repeatable data with no difference related to operator experience.

Keratoconus is a common degenerative corneal disease that can lead to significant visual morbidity, and both genetic and environmental factors have been implicated in its pathogenesis. We compared the transcriptome of keratoconus and control epithelium using RNA-Seq. Epithelial tissues were obtained prior to surgery from keratoconus and myopia control patients, undergoing collagen cross-linking and photorefractive keratectomy, respectively. We identified major differences in keratoconus linked to cell-cell communication, cell signalling and cellular metabolism. The genes associated with the Hedgehog, Wnt and Notch1 signaling pathways were down-regulated in keratoconus. We also identified plasmolipin and Notch1 as being significantly reduced in keratoconus for both gene and protein expression (p

Defining the threshold for therapeutic and surgical intervention in patients with keratoconus presents a considerable challenge given the lack of clear, evidence-based data. Little is known about the patterns of practice and referral criteria of optometrists within Australia.All members of the NSW branch of Optometrist Association Australia were invited to complete an online survey in January 2013. This survey was designed to elicit practice information regarding the evaluation and therapeutic treatment of patients with keratoconus in the optometric setting.Responses were received from 71 optometrists, of whom 65.2 per cent had 15 years or greater experience as an optometrist. Many (35.4 per cent) responded that they prescribed soft contact lenses daily. This percentage dropped to 9.2 per cent for rigid gas-permeable lenses (RGP), although 47.7 per cent said they would prescribe RGP lenses at least once per month. The main barriers to prescribing were experience with fitting RGP lenses, time and low market demand. In terms of patient referral to an ophthalmologist, the results were variable, with 34.4 per cent stating that they would refer on progression of corneal signs, 23.4 per cent suggesting no set time and 7.8 per cent would refer on initial diagnosis. Many optometrists (62.9 per cent) would refer a patient for possible surgery, when visual acuity dropped to between 6/9 and 6/12. The size or location of the practice was not associated with the number of newly diagnosed cases of keratoconus. Optometrists with greater experience were more likely to prescribe RGP lenses and co-manage patients with ophthalmologists. Ownership of a corneal topographic unit suggested an increased likelihood of prescribing RGP lenses but did not appear to alter referral patterns.Optometrists have an integral role in the diagnosis and management of patients with keratoconus. Our survey provides a basic snapshot of current, local practice. Additionally, ophthalmology should continue to work with optometry to develop guidelines for referral and co-management to optimise future outcomes for our patients.

Keratoconus (KC) is a progressive degenerative inflammatory-related disease of the human cornea leading to decreased visual function. The pathogenesis of KC remains to be understood. Recent genetic studies indicate that gene variants of an inflammation-related molecule, hepatocyte growth factor (HGF), are associated with an increased susceptibility for developing KC. However HGF protein expression in KC has not been explored. In this initial study, we investigated late-stage KC and control corneas for the expression of HGF and its receptor mesenchymal-epithelial transition factor (c-Met/Met). KC buttons (~8 mm diameter) (n=10) and whole control corneas (n=6) were fixed in 10% formalin or 2% paraformaldehyde, paraffin embedded and sectioned. Sections were immunolabelled with HGF and c-Met antibodies, visualised using immunofluorescence, and examined with scanning laser confocal microscopy. Semiquantitative grading was used to compare HGF and c-Met immunostaining in KC and control corneas. Overall, KC corneas showed increased HGF and c-Met immunostaining compared to controls. KC corneal epithelium displayed heterogeneous moderate-to-strong immunoreactivity for HGF and c-Met, particularly in the basal epithelium adjacent to the cone area. Taken together with the recent genetic studies, our results further support a possible role for HGF/c-Met in the pathogenesis of KC.