Robotising vitreoretinal surgeries.

The use of robotic surgery in ophthalmology has been shown to offer many potential advantages to current surgical techniques. Vitreoretinal surgery requires complex manoeuvres and high precision, and this is an area that exceeds manual human dexterity in certain surgical situations. With the advent of advanced therapeutics such as subretinal gene therapy, precise delivery and minimising trauma is imperative to optimize outcomes. There are multiple robotic systems in place for ophthalmology in pre-clinical and clinical use, and the Preceyes Robotic Surgical System (Preceyes BV) has also gained the CE mark and is commercially available for use. Recent in-vivo and in-human surgeries have been performed successfully with robotics systems. This includes membrane peeling, subretinal injections of therapeutics, and retinal vein cannulation. There is huge potential to integrate robotic surgery into mainstream clinical practice. In this review, we summarize the existing systems, and clinical implementation so far, and highlight the future clinical applications for robotic surgery in vitreo-retina.

Ocular Autoimmune Systemic Inflammatory Infectious Study (OASIS) - Report 6: Dengue Uveitis at a Tertiary Eye Institution in Singapore.

OBJECTIVES: To identify the characteristics, treatment, and visual outcomes of dengue uveitis at a tertiary eye care centre in Singapore. METHODS: Retrospective case record review of all consecutive dengue uveitis patients (2004 to 2015) from the Ocular Autoimmune Systemic Inflammatory and Infectious Study (OASIS) database. RESULTS: Fifty-four patients were identified from the OASIS database. The most common ocular symptom was blurring of vision (n = 41, 75.9%), followed by floaters (n = 9, 17.0%), scotoma (n = 5, 9.3%), and metamorphopsia (n = 3, 5.7%). Scotoma based on history, Amsler grid, and perimetry accounted for 27 (50%) patients. Majority presented with either a posterior uveitis or retinal vasculitis (n = 51, 94.4%). Treatments ranged from close observation for spontaneous improvement, to the use of high-dose corticosteroids. CONCLUSIONS: Dengue uveitis may present with a spectrum of disease manifestations including posterior uveitis, vasculitis, and macula edema. Scotoma is significant and may be found on history taking, Amsler charting, and perimetry.

Endogenous Endophthalmitis - A Major Review.

Endogenous endophthalmitis (EE) is an uncommon but potentially devastating ocular infection involving the inner layers of the eye. The global incidence of EE is on the rise. Common ocular signs and symptoms associated with EE include conjunctival injection, ocular pain, and reduced visual acuity. On clinical examination, a history of prior or coexisting systemic infections, symptoms (e.g., fever, malaise), and localizing features may be noted. Clinical diagnosis is often challenging, resulting in critical delays that contribute to a poor prognosis. Blood cultures and ocular fluid samples can aid in conforming causative pathogen(s), after which empirical antibiotic therapy, both systemic and intravitreal, should be instated. The use of steroids to suppress inflammation remains controversial. Surgical options include pars plana vitrectomy. Overall prognosis varies depending on host and pathogen factors, and early diagnosis and initiation of appropriate treatment are crucial.

Ocular Autoimmune Systemic Inflammatory Infectious Study (OASIS) - Report 2: Pattern of Uveitis Investigations in Singapore.

Purpose: To analyze the pattern of laboratory investigations of uveitis at a tertiary referral eye care center in Singapore.Methods: Retrospective analysis of 2040 uveitis cases from the Ocular Autoimmune Systemic Inflammatory Infectious Study (OASIS) database over a 12-year period (2004 - 2015).Results: Patients with retinal vasculitis (RV) had the most tests utilized per patient (6.79), followed by intermediate uveitis (IU) (5.25), panuveitis (Pan) (5.12), posterior uveitis (PU) (4.17), anterior uveitis (AU) (2.75), and keratouveitis (KU) (1.10). The most frequently utilized test for infective etiology were the VDRL (41.3%), Syphilis IgG (29.5%), and T-SPOT.TB (24.6%). For autoimmune tests, ANA was most utilized (18.2%), followed by anti-dsDNA (14.8%), and HLA-B27 (12.4%).Conclusion: There was high utilization of autoimmune tests such as ANA, anti-dsDNA, RF, and ANCA, despite its limited yield. Rationalization of investigations in patients with ocular inflammation via a stepladder approach may help optimize the use of limited resources.

Ocular Autoimmune Systemic Inflammatory Infectious Study - Report 3: Posterior and Panuveitis.

PURPOSE: To report the pattern of posterior and panuveitis at a tertiary referral center in Singapore. METHODS: Subgroup retrospective analysis of 334 new posterior and panuveitis cases, from the Ocular Autoimmune Systemic Inflammatory Infectious Study (OASIS) database. Descriptive analysis was performed and visual outcome and complications were reported. RESULTS: The etiology for posterior uveitis and panuveitis was infectious in 162 patients (48.5%), non-infectious in 144 patients (43.1%), and idiopathic in 28 patients (8.4%). More patients with bilateral disease had a non-infectious etiology (n = 82, 50.9%) (p = 0.012). The most common complication was epiretinal membrane (n = 20, 12.3%) for the infectious group and cystoid macular edema (n = 12, 8.3%) for the non-infectious group. CONCLUSIONS: The proportion of etiologies in our cohort varies from other studies. Understanding the variations and demographic associations allows the diagnosis and management of posterior and panuveitis to be further improved.

Ocular Autoimmune Systemic Inflammatory Infectious Study (OASIS) - Report 1: Epidemiology and Classification.

PURPOSE: To report the epidemiology and classification of ocular inflammation at a tertiary eye care center in Singapore. METHODS: Retrospective cohort study of the clinical records of consecutive new cases from the Ocular Autoimmune Systemic Inflammatory Infectious Study (OASIS) database from 2004-2015. RESULTS: A total of 2200 patients were studied from the OASIS database. The most common anatomic diagnosis was anterior uveitis (55.9%), posterior uveitis (17.5%), panuveitis (9.6%), and intermediate uveitis (4.7%). In addition, scleritis (6.1%), keratouveitis (2.8%), retinal vasculitis (2.2%), and episcleritis (1.2%) were observed. Etiology was established in 65.1%, with 35.2% of patients associated with non-infectious etiologies. The most common etiologies found were presumed tuberculosis (7.2%), followed by cytomegalovirus infection (6.9%), herpetic infection (6.3%), HLA-B27-associated anterior uveitis (4.2%), and ankylosing spondylitis (3.8%). CONCLUSIONS: The pattern of ocular inflammation in Singapore has similarities with both Western and Asian populations. Anterior uveitis was the most common, with non-infectious etiologies being slightly more common than infectious etiologies.

Comparison of anterior and posterior topographic analysis between 3 imaging systems.

PURPOSE: To evaluate and compare (anterior and posterior) corneal parameters obtained by use of 3 corneal topography devices. SETTING: Tertiary referral eye center, Singapore. DESIGN: Prospective observational study. METHODS: Corneal measurements were obtained from 30 normal eyes and 40 eyes after Descemet-stripping automated endothelial keratoplasty (DSAEK) with use of the spectral-domain AS-OCT device, Scheimpflug device, and time-domain AS-OCT device. The posterior area analyzed, anterior and posterior keratometric values, keratometric power, and pachymetry were compared. RESULTS: The spectral-domain AS-OCT device was able to capture the highest posterior area analyzed (86.2% ± 6.7%) compared with the Scheimpflug device (56.8% ± 11.9%) and the time-domain AS-OCT device (68.8% ± 12.3%) (P < .001). Intra-class coefficients (ICC) indicated strong agreement between devices in anterior keratometry (ICCs between 0.9 to 1.0) in both normal and DSAEK eyes. Agreement was poor to moderate for normal eyes (ICCs between 0.6 to 0.9) but poor in DSAEK eyes (ICCs between 0.60 to 0.7). For corneal pachymetry, agreement was moderate to strong for normal eyes (ICCs between 0.8 to 1.0) but showed poor to moderate agreement in DSAEK eyes (ICCs between 0.5 to 0.8). Vector analysis plots for mean astigmatism values showed greater differences between devices in anterior values compared with posterior values in both groups. CONCLUSION: Although the agreement between imaging systems was good for anterior corneal topography, posterior corneal topography had moderate agreement in normal eyes and poor agreement in eyes after endothelial keratoplasty.

Trends in Patterns of Posterior Uveitis and Panuveitis in a Tertiary Institution in Singapore.

PURPOSE: The study aims to analyze the trends of posterior uveitis and panuveitis patients seen by a tertiary eye center in Singapore between 2004 and 2012. METHODS: We conducted a retrospective analysis of 363 consecutive new cases of posterior uveitis and panuveitis. The cases were segregated into idiopathic, infectious, or noninfectious. RESULTS: We found statistically significant differences between etiologies and ethnicity (p = 0.014). We noticed a statistically significant downward trend (Spearman's rho (ρ) = -0.812, p = 0.008) for dengue uveitis, and an upward trend for the idiopathic category (Spearman's rho (ρ) = 0.753, p = 0.019). CONCLUSIONS: We observed differences between etiologies and ethnicity, pointing toward potential susceptibility variations. There was an upward trend of idiopathic causes, possibly due to better control of systemic and infectious etiologies. The dengue uveitis incidence correlates well with our national statistics. The downward trend of dengue uveitis could be due to the introduction of Singapore's dengue surveillance in 2005, emphasizing the importance of controlling the disease.

Trends in patterns of intermediate uveitis in a tertiary institution in Singapore.

PURPOSE: The study aims to describe the characteristics and etiologic causes of intermediate uveitis (IU) patients seen by a tertiary eye center in Singapore over 8 years. METHODS: This was a retrospective analysis of the clinical records of consecutive new cases of IU that presented to the uveitis subspecialty clinic from 2004-2011 at Tan Tock Seng Hospital. Data collected included demographics, clinical and laboratory findings. Diagnoses were based on standardized clinical history, ophthalmological examination and investigations. RESULTS: There were 66 new cases of IU, comprising 5.7% of 1168 new uveitis patients. The median age of diagnosis was 40 years (mean 39.4±15.9), with largest subgroup of the patients in the age group of 41-60 years (36.4%). The majority was Chinese (57.6%), followed by Asian Indians (18.2%) and Malays (16.7%). The ethnicity distribution was dissimilar to our ethnic distribution in Singapore (p<0.001) with an increased incidence of IU in the Asian Indian population. Most were idiopathic (59.1%) in etiology, followed by tuberculosis (TB) (15.2%). Ocular complications developed in 21 patients (31.8%), with cystoid macular edema (CME) being the commonest (28.8%). Severe vitritis occurred in 9.1% of patients, and was significantly associated with TB-associated IU (p<0.001). There was a downward trend for the incidence of the proportion of IU patients over the total uveitis patients (p = 0.021), with Spearman's rho of -0.786. CONCLUSIONS: Despite the downward trend, TB-associated IU was still of higher prevalence compared to less endemic areas, emphasizing the need for increased TB surveillance. A high index of suspicion for TB-associated IU is required in patients with severe vitritis. Comparisons with other countries revealed disparities in the IU etiologies, indicating possible geographical differences. Prevalence of known immune-mediated etiologies of IU is less compared to the western population. Our study also suggests a probable predisposition of the Singapore local Indian population for IU.