Comparison of Perfluorodecalin and Silicone Oil as Initial Tamponade for Giant Retinal Tear-Associated Retinal Detachment.

INTRODUCTION: To compare visual outcomes and complication rates of giant retinal tear-associated retinal detachment (GRT-RD) cases treated with short-term perfluorodecalin (PFD) tamponade versus silicone oil (SiO). METHODS: Database analysis of patients with GRT-RD operated on in the period from 1 January 2014 to 31 December 2019. RESULTS: Forty-five patients were operated for GRT-RD using PFD or SiO during this period. Two children, 7 patients receiving gas tamponade, and 2 lost to follow-up were excluded. Eighteen eyes (40%) received PFD and 27 (60%) received SiO. There were 15/18 (83%) macula-sparing cases in the PFD group and 18/27 (67%) in the SiO group (p = 0.13). The mean duration of oil tamponade was 91 days for SiO and 7.6 days for PFD (p < 0.0001). The mean length of follow-up was 274.5 days for PFD and 668.9 days for SiO. The mean BCVA was 6/18 (63.4 ± 26.0 ETDRS letters) for SiO and 6/12 (72.9 ± 12.7 ETDRS letters) for PFD (p = 0.42). Analysing macula-sparing pseudophakic eyes, the BCVA was 6/12 (67.4 ± 25.9 letters, n = 18) for SiO eyes and 6/9 (76.8 ± 9.9 letters, n = 11) for PFD eyes (p = 0.54). The recurrence rate was 22% (6/27) for SiO and 6% (1/18) for PFD (p = 0.12). The rate of cystoid macular oedema (CMO) was 22% for SiO and 22% for PFD. Epiretinal membrane (ERM) was found in 26% of SiO cases and 22% of PFD cases. Loss of vision after oil removal was not observed. Seven eyes (26%) receiving SiO and none receiving PFD developed chronic ocular hypertension (OHT) (p = 0.02). CONCLUSIONS: Short-term tamponade with PFD for GRT-RD appears similar to tamponade with SiO in terms of the visual outcomes and complication rates.

Assessing visible aerosol generation during vitrectomy in the era of Covid-19.

OBJECTIVE: To assess visible aerosol generation during simulated vitrectomy surgery. METHODS: A model comprising a human cadaveric corneoscleral rim mounted on an artificial anterior chamber was used. Three-port 25 gauge vitrectomy simulated surgery was performed with any visible aerosol production recorded using high-speed 4K camera. The following were assessed: (1) vitrector at maximum cut rate in static and dynamic conditions inside the model, (2) vitrector at air-fluid interface in a physical model, (3) passive fluid-air exchange with a backflush hand piece, (4) valved cannulas under air, and (5) a defective valved cannula under air. RESULTS: No visible aerosol or droplets were identified when the vitrector was used within the model. In the physical model, no visible aerosol or droplets were seen when the vitrector was engaged at the air-fluid interface. Droplets were produced from the opening of backflush hand piece during passive fluid-air exchange. No visible aerosol was produced from the intact valved cannulas under air pressure, but droplets were seen at the beginning of fluid-air exchange when the valved cannula was defective. CONCLUSIONS: We found no evidence of visible aerosol generation during simulated vitrectomy surgery with competent valved cannulas. In the physical model, no visible aerosol was generated by the high-speed vitrector despite cutting at the air-fluid interface.

PRDX3 is associated with metastasis and poor survival in uveal melanoma.

AIMS: Uveal melanoma (UM) is the most common primary intraocular malignancy in adults, and 40% develop fatal metastatic disease. Overexpression of thioredoxin-dependent peroxidase reductase (PRDX3) has been implicated in several cancers, including prostate, breast, colorectal and lung cancer. The aim of this study was to compare the immunohistochemical expression of PRDX3 in formalin-fixed, paraffin-embedded (FFPE) primary UM tissues of patients who did and did not develop metastatic disease. METHODS: Immunohistochemical staining of PRDX3 was performed on FFPE tissue microarray samples of 92 primary UM tumours from patients who did and did not develop metastatic disease. The immunohistochemical staining was assessed by two observers who were blinded to all clinicopathological and cytogenetic details including metastatic/non-metastatic information. Based on a scoring system, expression of PRDX3 was graded as high or low. RESULTS: There were 55 tumours (59.8%) from patients who developed metastatic disease, while 37 (40.2%) were from patients who did not develop metastasis. A statistically significant difference in PRDX3 expression was observed in patients who did and did not develop metastasis (p=0.001). A significant positive correlation between high PRDX3 expression and metastasis was observed (p=0.001). A significant negative correlation between PRDX3 expression and survival was found (p=0.005). Kaplan-Meier survival analysis showed a statistically significant difference in overall survival between tumours that demonstrated low and high expression of PRDX3 (67.61 vs 130.64 months, respectively, p=0.013). CONCLUSIONS: High immunohistochemical expression of PRDX3 in primary UM tissue is associated with metastasis and poor survival.

The Effect of Anterior Uveitis and Previously Undiagnosed Spondyloarthritis: Results from the DUET Cohort.

OBJECTIVE: Anterior uveitis (AU) is an intraocular inflammatory condition closely linked to spondyloarthritis (SpA). Clinical disease variables may often underestimate the true effect of the disease on patient's quality of life. This study examines AU and associated undiagnosed SpA using established quality-of-life tools to inform clinicians of the effect of these diseases. METHODS: The Dublin Uveitis Evaluation Tool (DUET) algorithm was developed and validated in a cohort of consecutive patients with AU who were all screened by a rheumatologist for the presence of SpA. This same cohort completed vision-related [Vision Core Measure 1 (VCM1)] and general health [Medical Outcomes Study Short Form-36 (SF-36)] questionnaires when AU was active and resolved. RESULTS: VCM1 scores improved with AU resolution. VCM1 did not correlate with vision at baseline, but did on resolution of inflammation. Physical SF-36 scores were reduced during AU episodes and improved on resolution remaining below those of population norms. Subanalysis revealed that SpA scores were more affected than the idiopathic AU group. CONCLUSION: AU affects physical aspects of quality of life more than is appreciated by clinical variables, especially in those with pre-existing, undiagnosed SpA. This study is unique in examining the effect of SpA on patients prior to diagnosis. These results highlight the role of the ophthalmologist in identifying patients with SpA who present with AU using the DUET algorithm.

A novel evidence-based detection of undiagnosed spondyloarthritis in patients presenting with acute anterior uveitis: the DUET (Dublin Uveitis Evaluation Tool).

BACKGROUND: To date, there are no formal guidelines or referral pathways for acute anterior uveitis (AAU) patients developed or endorsed by any international or national societies. The objective of our study was to develop and validate an assessment algorithm for referral from ophthalmologists of appropriate AAU patients to rheumatology that will aid the early diagnosis of the spondyloarthropathy (SpA). METHODS: All consecutive patients attending the emergency department of local ophthalmology hospital with AAU, but who did not have a known diagnosis of SpA, were eligible to participate in this study. Patients with any other known cause of AAU were excluded. Two independent cohorts were enrolled. Test algorithm and Dublin Uveitis Evaluation Tool (DUET) algorithm (revised form of test algorithm) were used in these cohorts to identify patients as SpA suspects and non-SpA controls, respectively. RESULTS: STUDY PHASE-1. ALGORITHM DEVELOPMENT COHORT (n=101): After rheumatologic evaluation of the entire cohort, 41.6% (n=42) had undiagnosed SpA. Our test algorithm was noted to have: sensitivity 100% and specificity 53.5%. Further regression analysis resulted in the development of the DUET algorithm which made the following improvements: sensitivity 95%, specificity 98%, positive likelihood ratio (LR) 56.19, and negative LR 0.04. STUDY PHASE-2. DUET ALGORITHM VALIDATION COHORT (n=72): After rheumatologic evaluation of the cohort, 40% (n=29) were diagnosed with SpA, with the following performance of DUET algorithm-sensitivity 96%, specificity 97%, positive LR 41.5 and negative LR 0.03. CONCLUSIONS: Approximately 40% of patients presenting with idiopathic AAU have undiagnosed SpA. A simple to apply algorithm is described with excellent sensitivity and specificity.

Proteomics in uveal melanoma.

Uveal melanoma is the most common primary intraocular malignancy in adults, with an incidence of 5-7 per million per year. It is associated with the development of metastasis in about 50% of cases, and 40% of patients with uveal melanoma die of metastatic disease despite successful treatment of the primary tumour. The survival rates at 5, 10 and 15 years are 65%, 50% and 45% respectively. Unlike progress made in many other areas of cancer, uveal melanoma is still poorly understood and survival rates have remained similar over the past 25 years. Recently, advances made in molecular genetics have improved our understanding of this disease and stratification of patients into low risk and high risk for developing metastasis. However, only a limited number of studies have been performed using proteomic methods. This review will give an overview of various proteomic technologies currently employed in life sciences research, and discuss proteomic studies of uveal melanoma.