Patch endothelial keratoplasty for corneal perforations secondary to ocular surface disease: case series.

BACKGROUND: Corneal perforation is an ophthalmic emergency. The conventional management of corneal perforation can be associated with severe complications especially in patients with ocular surface disease. Endothelial keratoplasty has been suggested as an alternative surgical technique for the management of corneal perforations. We present a case series of nine patients with corneal perforation and ocular surface disease managed with secondary patch endothelial keratoplasty. METHODS: This is a retrospective case series of nine patch endothelial keratoplasties performed between 2016 and 2022 at a quaternary eye hospital in Australia. The surgical technique is similar to conventional endothelial keratoplasty except descemetorhexis was not performed. RESULTS: A total of 9 cases were treated during the review period. Eight of the nine cases had an improvement in visual acuity. One case failed to achieve corneal tectonic objective. CONCLUSION: Patch endothelial keratoplasty is a safe secondary procedure for the management of corneal perforations in patients with ocular surface disease.

Automatic Refractive Error Estimation Using Deep Learning-Based Analysis of Red Reflex Images.

Purpose/Background: We evaluate how a deep learning model can be applied to extract refractive error metrics from pupillary red reflex images taken by a low-cost handheld fundus camera. This could potentially provide a rapid and economical vision-screening method, allowing for early intervention to prevent myopic progression and reduce the socioeconomic burden associated with vision impairment in the later stages of life. Methods: Infrared and color images of pupillary crescents were extracted from eccentric photorefraction images of participants from Choithram Hospital in India and Dargaville Medical Center in New Zealand. The pre-processed images were then used to train different convolutional neural networks to predict refractive error in terms of spherical power and cylindrical power metrics. Results: The best-performing trained model achieved an overall accuracy of 75% for predicting spherical power using infrared images and a multiclass classifier. Conclusions: Even though the model's performance is not superior, the proposed method showed good usability of using red reflex images in estimating refractive error. Such an approach has never been experimented with before and can help guide researchers, especially when the future of eye care is moving towards highly portable and smartphone-based devices.

Case Series of Rare Fungal Keratitides: Experiences from a Quaternary Eye Hospital in Sydney, Australia.

The present article reports on the management of six different and rare cases of fungal keratitides, two of which have never been documented in previous literature. This is a case series of six patients with rare fungal keratitides managed at a quaternary eye referral unit, Sydney Eye Hospital, Australia over a period of 7 months (May to December, 2022). The order of occurrence of fungi isolated was Scedosporium apiospermum, Lomenstospora prolificans, Cladosporium spp., Paecilomyces, Syncephalastrum racemosum and Quambalaria spp. A combination of medical and surgical interventions was employed, including topical and systemic anti-fungal therapy, with one requiring therapeutic penetrating keratoplasty and another eventuating in evisceration. Two patients were successfully treated with corneal debridement and two others required pars plana vitrectomy with anterior chamber washout. It is important to remain vigilant with monitoring patient symptoms and correlating with clinical signs to guide antifungal therapy even in the context of confirmed culture and sensitivity results.

Genotypic and phenotypic characterisation of RP2- and RPGR-associated X-linked inherited retinal dystrophy, including female manifestations.

BACKGROUND: With the promise of gene replacement therapy, eligible males and females with X-linked inherited retinal dystrophy (XL-IRD) should be identified. METHODS: Retrospective observational cohort study to establish the phenotypic and genotypic spectrum of XL-IRD within New Zealand (NZ). Thirty-two probands, including 9 females, with molecularly proven XL-IRD due to RP2 or RPGR mutations, and 72 family members, of which 43 were affected, were identified from the NZ IRD Database. Comprehensive ophthalmic phenotyping, familial cosegregation, genotyping, and bioinformatics were undertaken. Main outcome measures were: RP2 and RPGR pathogenic variant spectrum, phenotype in males and females (symptoms, age of onset, visual acuity, refraction, electrophysiology, autofluorescence, retinal appearance), and genotype-phenotype correlation. RESULTS: For 32 families, 26 unique pathogenic variants were identified; in RP2 (n = 6, 21.9% of all families), RPGR exons 1-14 (n = 10, 43.75%), and RPGR-ORF15 (n = 10, 34.3%). Three RP2 and 8 RPGR exons 1-14 variants are novel, rare, and cosegregate. Thirty-one percent of carrier females were significantly affected, with 18.5% of families initially classified as autosomal dominant. Of five Polynesian families, 80% had novel disease-causing variants. One Maori family showed keratoconus segregating with an ORF15 variant. CONCLUSIONS: Significant disease was present in 31% of genetically proven female carriers, often leading to an erroneous presumption of the inheritance pattern. Pathogenic variants in 44% of the families were in exon 1-14 of RPGR, more frequent than usually described, which may inform the gene testing algorithm. Proving cosegregation in families for novel variants and identifying affected females and males translates to optimised clinical care and potential for gene therapy.

Photorefraction Screening Plus Atropine Treatment for Myopia is Cost-Effective: A Proof-of-Concept Markov Analysis.

Purpose: The prevalence of myopia is increasing globally, putting individuals at risk of myopia-associated visual impairment. Low-dose atropine eye drops have been found to safely reduce the risk of progression from myopia to higher levels of myopia and pathological states. In New Zealand, school children have an eye check at age 11. In this study, we aimed to estimate the cost-effectiveness of introducing photorefractive screening for myopia at age 11 in the New Zealand context, with atropine 0.01% eye drops treatment for those screening positive. Patients and Methods: A Markov cohort simulation was used to model the impact of screening plus atropine compared to usual care across a lifetime horizon and societal perspective with a 3% discount rate. Cost-effectiveness was determined by the incremental cost-effectiveness ratio (ICER), with utility measured in quality-adjusted life-years (QALYs). Multivariate sensitivity analyses were carried out to investigate factors influencing cost-effectiveness. Results: The ICER for screening plus atropine was NZ$1590 (95% CI 1390, 1791) per QALY gained, with 7 cases of lifetime blindness prevented per 100,000 children screened. Conclusion: Screening for myopia with photorefraction at age 11 and atropine 0.01% eye drop treatment of children screening positive is likely to be cost-effective. These results suggest that a real-world trial and cost-effectiveness analysis would be worth considering in New Zealand.

A new approach to non-mydriatic portable fundus imaging.

INTRODUCTION: The present study proposes a new hand-held non-mydriatic fundus camera for retinal imaging. The goal is to design a fundus camera which is equally effective in both clinical and telemedicine scenarios. AREAS COVERED: A new retinal illumination approach is proposed to address the main dilemma of the optical design, i.e. balancing efficacy with structural simplicity. This is achieved by symmetrical and co-axial placement of multiple illumination sources along the optical pathway. Each illumination source includes a white and a Near Infra-Red (NIR) LED, which are placed adjacent to each other. Hence, the camera can produce a view-finder with NIR illumination without the need for additional beam-splitters and filters. EXPERT OPINION: The proposed design blends the structural simplicity of the 'off-axis illumination with the wide field of view and uniform illumination of the 'ring' illumination. Moreover, the camera is designed to work with Android-based smartphones, which can easily be mounted and interfaced. The efficacy of the proposed camera is determined by ocular safety analysis and comparative evaluation with a table-top fundus camera. The results convincingly demonstrate the ability of the proposed camera as a primary driver of a wide-scale screening program in both clinical and remote resource constraint environments.

A Systematic Review of Current Teleophthalmology Services in New Zealand Compared to the Four Comparable Countries of the United Kingdom, Australia, United States of America (USA) and Canada.

BACKGROUND: Over 700,000 New Zealanders (NZ), particularly elderly and Maori, live without timely access to specialist ophthalmology services. Teleophthalmology is a widely recognised tool that can assist in overcoming resource and distance barriers. Teleophthalmology gained unprecedented traction in NZ during the COVID-19 pandemic and subsequent lockdown. However, its provision is still limited and there are equity issues. The aim of this study was to conduct a systematic review identifying, describing and contrasting teleophthalmology services in NZ with the comparable countries of Australia, USA, Canada and the United Kingdom. METHODS: The electronic databases Embase, PubMed, Web of Science, Google Scholar and Google were systemically searched using the keywords: telemedicine, ophthalmology, tele-ophthalmology/teleophthalmology. The searches were filtered to the countries above, with no time constraints. An integrative approach was used to synthesise findings. RESULTS: One hundred and thirty-two studies were identified describing 90 discrete teleophthalmology services. Articles spanned from 1997 to 2020. Models were categorised into general eye care (n=21; 16%); emergency/trauma (n=6; 4.5%); school screening (n=25; 19%); artificial intelligence (AI) (n=23; 18%); and disease-specific models of care (MOC) (n=57; 43%). The most common diseases addressed were diabetic retinopathy (n=23; 17%); retinopathy of prematurity (n=9; 7%); and glaucoma (n=8; 6%). Programs were mainly centred in the US (n=72; 54.5%), followed by the UK (n=29; 22%), then Canada (n=16; 12%), Australia (n=13; 10%), with the fewest identified in NZ (n=3; 2%). Models generally involved an ophthalmologist consultative service, remote supervision and triaging. Most models involved local clinicians transmitting fed-forward or live images. CONCLUSION: Teleophthalmology will likely play a crucial role in the future of eye care. COVID-19 has offered a unique opportunity to observe the use of teleophthalmology services globally. Feed-forward and, increasingly, live-based teleophthalmology services have demonstrated feasibility and cost-effectiveness in similar countries internationally. New Zealand's teleophthalmology services, however, are currently limited. Investing in strategic partnerships and technology at a national level can advance health equities in ophthalmic care.

On the use of a new monocular-indirect ophthalmoscope for retinal photography in a primary care setting.

AIM: There is consensus among general practitioners regarding the difficulty of direct ophthalmoscopy. Hence, there is increasing interest in smartphone-based ophthalmoscopes; the New Zealand-made oDocs Nun ophthalmoscope is one such device, released in November 2018. This study aims to subjectively assess the quality of the images captured with it in order to determine the feasibility of its use in a primary care setting. METHOD: Twenty-eight general practitioners (GPs) from different practices throughout New Zealand agreed to participate in this prospective observational study and were sent an oDocs Nun ophthalmoscope. Using the device, clinicians took retinal photographs of patients who presented with visual complaints and uploaded one image per eye onto a database. Three hundred and fifty-seven photographs were collated and rated by four professionals (two ophthalmologists and two optometrists) on the basis of image quality and the anatomical features visible. RESULTS: On a Likert scale from 1 (poor quality) to 4 (very good quality), the median and mode values for each professional's rating of all photographs were both 2. On average, 94.5% of the photographs were deemed to have visible optic discs and 50.0% to have visible maculae adequate for detecting an abnormality. Pairwise comparison showed 93.7% agreement among the four professionals for optic disc visibility, and 74.2% agreement for macula visibility. CONCLUSION: The oDocs Nun is a promising tool which GPs could use to circumvent the challenges associated with direct ophthalmoscopy. With appropriate training to ensure proficiency, it may have a valuable role in telemedicine and tele-referral.

The Detection of Spontaneous Venous Pulsation with Smartphone Video Ophthalmoscopy.

PURPOSE: Spontaneous venous pulsation (SVP) has a high negative predictive value for raised intracranial pressure and is a useful sign when assessing patients with headache. The objective was to determine if smartphone-based video ophthalmoscopy can detect SVP. PATIENTS AND METHODS: In total 233 patients and 291 eyes were recruited from the Dunedin Hospital eye clinic from July to November 2018. Patients were examined by a clinician and graded for SVP with a slit lamp and 78 Dioptre lens. Videos were taken with a smartphone ophthalmoscope and graded by two separate clinicians blinded to the slit lamp findings. RESULTS: Only 272 eyes of 215 patients were included, as others failed in the inclusion criteria for overall video quality. Sensitivity was calculated as how likely the presence of SVP on video was indicative of the presence of SVP on slit lamp. Sensitivity was 84.77% for Observer 1, with 128 videos graded as positive for SVP on video ophthalmoscopy of the 151 identified as positive on slit lamp examination. Sensitivity was 76.82% for Observer 2 with 116 videos correctly identified. The false positive rate was calculated as the number of videos graded positive for SVP that had been graded as negative on slit lamp examination. This was 10.74% for observer 1 and 31.40% for observer 2. CONCLUSION: This study demonstrates that SVP is detected by video ophthalmoscopy. This may be a useful triage, telemedicine and referral tool to be used for patients with headache in a primary care setting.

Development of an artificial intelligence system to classify pathology and clinical features on retinal fundus images.

IMPORTANCE: Artificial intelligence (AI) algorithms are under development for use in diabetic retinopathy photo screening pathways. To be clinically acceptable, such systems must also be able to classify other fundus abnormalities and clinical features at the point of care. BACKGROUND: We aimed to develop an AI system that can detect several fundus pathologies and report relevant clinical features. DESIGN: Convolutional neural network training with retrospective data set. PARTICIPANTS: Colour fundus photos were obtained from publicly available fundus image databases. METHODS: Images were uploaded to a web-based AI platform for training and validation of AI classifiers. Separate classifiers were created for each fundus pathology and clinical feature. MAIN OUTCOME MEASURES: Accuracy, sensitivity, specificity and area under receiver operating characteristic curve (AUC) for each classifier. RESULTS: We obtained 4435 images from publicly available fundus image databases. AI classifiers were developed for each disease state above. Although statistical performance was limited by the small sample size, average accuracy was 89%, average sensitivity was 75%, average specificity was 89% and average AUC was 0.58. CONCLUSION AND RELEVANCE: This study is a proof-of-concept AI system that could be implemented within a diabetic photo-screening pathway. Performance was promising but not yet at the level that would be required for clinical application. We have shown that it is possible for clinicians to develop AI classifiers with no previous programming or AI knowledge, using standard laptop computers.

Diabetic retinopathy screening using deep neural network.

IMPORTANCE: There is a burgeoning interest in the use of deep neural network in diabetic retinal screening. BACKGROUND: To determine whether a deep neural network could satisfactorily detect diabetic retinopathy that requires referral to an ophthalmologist from a local diabetic retinal screening programme and an international database. DESIGN: Retrospective audit. PARTICIPANTS: Diabetic retinal photos from Otago database photographed during October 2016 (485 photos), and 1200 photos from Messidor international database. METHODS: Receiver operating characteristic curve to illustrate the ability of a deep neural network to identify referable diabetic retinopathy (moderate or worse diabetic retinopathy or exudates within one disc diameter of the fovea). MAIN OUTCOME MEASURES: Area under the receiver operating characteristic curve, sensitivity and specificity. RESULTS: For detecting referable diabetic retinopathy, the deep neural network had an area under receiver operating characteristic curve of 0.901 (95% confidence interval 0.807-0.995), with 84.6% sensitivity and 79.7% specificity for Otago and 0.980 (95% confidence interval 0.973-0.986), with 96.0% sensitivity and 90.0% specificity for Messidor. CONCLUSIONS AND RELEVANCE: This study has shown that a deep neural network can detect referable diabetic retinopathy with sensitivities and specificities close to or better than 80% from both an international and a domestic (New Zealand) database. We believe that deep neural networks can be integrated into community screening once they can successfully detect both diabetic retinopathy and diabetic macular oedema.

Safety of iPhone retinal photography.

BACKGROUND: With the advancement in mobile technology, smartphone retinal photography is becoming a popular practice. However, there is limited information about the safety of the latest smartphones used for retinal photography. AIMS: This study aims to determine the photobiological risk of iPhone 6 and iPhone 6 plus when used in conjunction with a 20Diopter condensing lens for retinal photography. METHOD: iPhone 6 and iPhone 6 plus (Apple, Cupertino, CA) were used in this study. The geometrical setup of the study was similar to the indirect ophthalmoscopy technique. The phone was set up at one end of the bench with its flash turned on at maximal brightness; a 20 Dioptre lens was placed 15 cm away from the phone. The light that passes through the lens was measured with a spectroradiometer and an illuminance probe at the other end to determine the spectral profile, spatial irradiance, radiant power emitted by the phone's flash. Trigonometric and lens formula were applied to determine the field of view and retinal surface in order to determine the weighted retinal irradiance and weighted retinal radiant exposure. RESULT: Taking ocular transmission and the distribution of the beam's spatial irradiance into account, the weighted retinal irradiance is 1.40 mW/cm2 and the weighted retinal radiant exposure is 56.25 mJ/cm2. The peak weighted foveal irradiance is 1.61 mW/cm2. CONCLUSION: Our study concluded that the photobiological risk posed by iPhone 6 indirect ophthalmoscopy was at least 1 order of magnitude below the safety limits set by the ISO15004-2.2.

Brain mushroom: A case of osteolytic intraosseous meningioma with transcalvaria herniation.

A 61-year-old male presented with primary intraosseous osteolytic meningioma and transcalvaria herniation. This is an extremely rare condition with only 16 case reports of osteolytic intraosseous meningioma. This case is unique because it was accompanied by a transcalvaria herniation.