Should Aquaporin-4 Antibody Test Be Performed in all Patients With Isolated Optic Neuritis?

BACKGROUND: Optic neuritis (ON) may be the initial manifestation of neuromyelitis optica spectrum disorder (NMOSD). Aquaporin-4 antibody (AQP4 Ab) is used to diagnose NMOSD. This has implications on prognosis and is important for optimal management. We aim to evaluate if clinical features can distinguish AQP4 Ab seropositive and seronegative ON patients. METHODS: We reviewed patients with first episode of isolated ON from Tan Tock Seng Hospital and Singapore National Eye Centre who tested for AQP4 Ab from 2008 to 2017. Demographic and clinical data were compared between seropositive and seronegative patients. RESULTS: Among 106 patients (120 eyes) with first episode of isolated ON, 23 (26 eyes; 22%) were AQP4 Ab positive and 83 (94 eyes; 78%) were AQP4 Ab negative. At presentation, AQP4 Ab positive patients had older mean onset age (47.9 ± 13.6 vs 36.8 ± 12.6 years, P < 0.001), worse nadir VA (OR 1.714; 95% CI, 1.36 to 2.16; P < 0.001), less optic disc swelling (OR 5.04; 95% CI, 1.682 to 15.073; p = 0.004), and higher proportions of concomitant anti-Ro antibody (17% vs 4%, p = 0.038) and anti-La antibody (17% vs 1%, p = 0.008). More AQP4 Ab positive patients received steroid-sparing immunosuppressants (74% vs 19%, p < 0.001) and plasma exchange (13% vs 0%, p = 0.009). AQP4 Ab positive patients had worse mean logMAR VA (visual acuity) at 12 months (0.70 ± 0.3 vs 0.29 ± 0.5, p = 0.051) and 36 months (0.37±0.4 vs 0.14 ± 0.2, p = 0.048) follow-up. CONCLUSION: Other than older onset age and retrobulbar optic neuritis, clinical features are non-discriminatory for NMOSD. We propose a low threshold for AQP4 Ab serology testing in inflammatory ON patients, particularly in high NMOSD prevalence populations, to minimize diagnostic and treatment delays.

Sustainable practice of ophthalmology during COVID-19: challenges and solutions.

PURPOSE: The Coronavirus (COVID-19) outbreak is rapidly emerging as a global health threat. With no proven vaccination or treatment, infection control measures are paramount. In this article, we aim to describe the impact of COVID-19 on our practice and share our strategies and guidelines to maintain a sustainable ophthalmology practice. METHODS: Tan Tock Seng Hospital (TTSH) Eye Centre is the only ophthalmology department supporting the National Centre for Infectious Diseases (NCID), which is the national screening center and the main center for management of COVID-19 patients in Singapore. Our guidelines during this outbreak are discussed. RESULTS: Challenges in different care settings in our ophthalmology practice have been identified and analyzed with practical solutions and guidelines implemented in anticipation of these challenges. First, to minimize cross-infection of COVID-19, stringent infection control measures were set up. These include personal protective equipment (PPE) for healthcare workers and routine cleaning of "high-touch" surfaces. Second, for outpatient care, a stringent dual screening and triaging process were carried out to identify high-risk patients, with proper isolation for such patients. Administrative measures to lower patient attendance and reschedule appointments were carried out. Third, inpatient and outpatient care were separated to minimize interactions. Last but not least, logistics and manpower plans were drawn up in anticipation of resource demands and measures to improve the mental well-being of staff were implemented. CONCLUSION: We hope our measures during this COVID-19 pandemic can help ophthalmologists globally and serve to guide and maintain safe access in ophthalmology clinics when faced with similar disease outbreaks.

Traumatic Globe Luxation With Chiasmal Avulsion.

BACKGROUND: To describe an unusual case of traumatic globe luxation with optic chiasmal avulsion and review the existing literature on this rare condition for further discussion of mechanisms, diagnosis, and management. METHODS: Case report and review of existing case reports and case series identified through literature search. RESULTS: A 28-year-old woman, with no previous medical history, had left globe luxation and optic chiasm avulsion after being stabbed directly into the left orbit with the use of the stiletto high heel of a shoe. Automated visual field testing detected a temporal hemianopia in the unaffected eye despite normal central visual acuity. Chiasmal avulsion was demonstrated by MRI. CONCLUSIONS: This case suggests that perimetry and MRI should always be considered in traumatic globe luxation to localize the site of injury. Temporal hemianopia in the fellow eye indicates a concomitant chiasmal injury.

Case of unilateral anaemic retinopathy unmasking colorectal carcinoma.

Anaemic retinopathy presents commonly with bilateral retinal haemorrhages and soft exudates. Unilateral optic disc oedema in these patients has rarely been mentioned. We report a case of an atypical presentation of anaemic retinopathy with recurrent unilateral optic disc oedema and retinal haemorrhages secondary to iron deficiency anaemia from a newly diagnosed colorectal adenocarcinoma.A man in his 70s with multiple ischaemic risk factors was referred for unilateral optic disc oedema associated with a few retinal haemorrhages. Initial diagnosis was that of impending central retinal vein occlusion. The optic disc oedema initially resolved but recurred 8 months later with worsening unilateral disc oedema, 'coin-shaped' retinal haemorrhages, Roth's spots and venous tortuosity. Full blood count showed microcytic hypochromic anaemia secondary to iron deficiency and colonoscopy revealed colorectal adenocarcinoma. The patient received blood transfusions, oral iron replacement and underwent surgical resection of the tumour. The anaemia resolved, and the fundus findings resolved as well.

Rarebit perimetry: normative values and test-retest variability.

BACKGROUND: We aim to establish normative values and evaluate test-retest variability for the central and foveal field tests of version 4 of rarebit perimetry. DESIGN: This was a prospective study undertaken in collaboration between Tan Tock Seng Hospital, Singapore, and Singapore Polytechnic. PARTICIPANTS: Fifty-four normal subjects were recruited and included in the study. METHODS: Subjects underwent rarebit perimetry testing, studying the central and foveal fields. All subjects repeated the test within 1 month of the initial visit. The 'mean hit rates' of one eye of every subject were analysed. MAIN OUTCOME MEASURES: Mean hit rates of subjects were analysed to establish normative values for the central and foveal fields. Test-retest variability was also analysed. RESULTS: Overall normative mean hit rates were 86.3 ± 13.95% for the central field and 91.6 ± 6.35% for the foveal field. For every increasing year of age, we found a 0.47% decrease in the central mean hit rates (P < 0.001). Normative mean hit rate for central and foveal fields were 90.6 ± 12.3% and 98.2 ± 3.7% respectively, in 'young' subjects, and 81.9 ± 15.6% and 85.0 ± 9.0% respectively, in 'mature' subjects. We found no significant test-retest variability in the foveal field (P = 0.554). There was significant test-retest variability in the central field (P < 0.001), but the difference was a 3.5 unit mean hit rate increase, which may be clinically significant. CONCLUSIONS: Rarebit perimetry is repeatable and reliable. We have established normative values for two age groups.

SARS in Singapore--predictors of disease severity.

INTRODUCTION: Severe acute respiratory syndrome (SARS) affected 8096 individuals in 29 countries, with 774 deaths. In Singapore, there were 238 cases of SARS with 33 deaths. A retrospective analysis was performed to identify predictors of poor outcome in patients with SARS locally. MATERIALS AND METHODS: Clinical, laboratory and outcome data of 234 patients admitted to Tan Tock Seng Hospital and Singapore General Hospital were collected and analysed. Only data collected at the time of admission were used in the analysis for predictors of poor outcome. Adverse events were defined as admission to the intensive care unit or death. RESULTS: Clinical (temperature, FiO2) and laboratory [leukocyte, lymphocyte, neutrophil, platelet, lactate dehydrogenase (LDH), albumin] trends in groups with and without an adversarial event were presented. Fifty patients experienced an adverse event. On univariate analysis, male gender, advanced age, presence of comorbidities, neutrophilia, lymphopaenia, hyponatraemia, hypoalbuminaemia, transaminitis and elevated LDH or C-reactive protein were found to be significant predictors. On multivariate analysis, predictors of poor outcome were increased age [odds ratio (OR) 1.73 for every 10-year increase; 95% CI, 1.35 to 2.21], neutrophilia (OR 1.06 for every 1 x 10(9)/L increase; 95% CI, 1.02 to 1.11) and high LDH (OR 1.17 for every 100 U/L increase; 95% CI, 1.02 to 1.34). None of the 12 paediatric patients had an adverse event. CONCLUSION: Advanced age, neutrophilia and high LDH predict poor outcomes in patients with SARS.