Outcomes of Heavy Silicone Oil (Densiron) compared to Silicone Oil in primary rhegmatogenous retinal detachment: a multivariable regression model

PURPOSE

To measure the visual outcomes, proliferative vitreoretinopathy (PVR) and retinectomy rates following primary rhegmatogenous retinal detachment (RRD) repair, comparing silicone oil (SO) and heavy SO (Densiron).

METHODS

Retrospective, continuous comparative study from January 2017 to May 2021 of all primary RRD. Multivariable linear (logMAR gain) and binary-logistic (PVR-C and retinectomy rate) regression models to compare tamponade were performed. Covariates included age, gender, ocular co-morbidities, high myopia, macula-status, giant-retinal-tear (GRT), pre-op vision, PVR-C, oil type, perfluorocarbon-use, combined scleral buckle/vitrectomy, combined phaco-vitrectomy, 360-degrees-endolaser and oil duration. Cases with trauma or less than six-month follow-up were excluded.

RESULTS

A total of 259 primary RD were analysed. There were 179 SO patients and 80 Densiron patients that had six-month primary re-detachment in 18 (10.1%) and 8 (10.0%) respectively (p = 1.000). No difference in logMAR gain was detected between tamponade choice on multivariable linear regression. Subsequent glaucoma surgery was 5 (2.8%) and 4 (5.0%) for SO and Densiron patients respectively (p = 0.464). On multivariate binary-logistic regression we found no difference in development of PVR-C between oil tamponades. However, SO had significantly higher subsequent retinectomy rate compared to Densiron (odds ratio 15.3, 95% CI 1.9-125.5, p = 0.011). Duration of oil tamponade was not linked to differences in logMAR gain, PVR-C formation or increased retinectomy rate.

CONCLUSIONS

We report no difference in primary anatomical success, number of further RRD surgeries, subsequent glaucoma surgery, visual outcomes, PVR-C between both tamponades on multivariable models. Densiron oil was found to be more retinectomy sparing relative to SO.

Calculating the economic burden of presumed microbial keratitis admissions at a tertiary referral centre in the UK

Purpose

Microbial keratitis (MK) is the most common non-surgical ophthalmic emergency admission in the UK. However, few prospective health-economic studies of MK have been performed, and no specific healthcare resources group (HRG) code exists. This study is designed to determine the feasibility of a data collection tool derived from the microbiology ophthalmology group (MOG) clinical record form, to enable quantification of direct costs of inpatient care, as well as prospective capture of epidemiological data relating to outcomes of MK.

Methods

Clinical, demographic and economic data were collected retrospectively between January and December 2013 for 101 consecutive patients admitted with MK, using an adaption of the MOG toolset. The direct cost of admission (COA) was calculated using national reference costs and compared to actual income to generate profit/deficit profiles for individual patients. Indices of multiple deprivation were used to assess effect of deprivation on the COA.

Results

The total income generated through discharge coding was £252,116, compared to a COA of £357,075, yielding a deficit of £104,960 (median: £754 per patient). The cost deficit increased significantly with length of stay (LOS, p < 0.001), whilst patients with short LOS were income generators; cost neutrality occurred at 4.8 days. Greater socioeconomic deprivation was also associated with a significantly higher cost deficit.

Conclusion

LOS is the key driver for COA of care for MK admissions. Protocols should encourage discharge of patients who are able to self-administer treatment after the sterilisation phase. The MOG-derived data collection toolset captures pertinent clinical data for quantification of COA. Further development into a multiuser and multisite platform is required for robust prospective testing, together with expansion to capture indirect costs of disease burden, including impact of treatment, visual morbidity and quality of life.

Deep Metagenomic Sequencing for Endophthalmitis Pathogen Detection Using a Nanopore Platform

PURPOSE

To evaluate the utility of nanopore sequencing for identifying potential causative pathogens in endophthalmitis, comparing culture results against full-length 16S rRNA nanopore sequencing (16S Nanopore), whole genome nanopore sequencing (Nanopore WGS), and Illumina (Illumina WGS).

DESIGN

Cross-sectional diagnostic comparison.

METHODS

Patients with clinically suspected endophthalmitis underwent intraocular vitreous biopsy as per standard care. Clinical samples were cultured by conventional methods, together with full-length 16S rRNA and WGS using nanopore and Illumina sequencing platforms.

RESULTS

Of 23 patients (median age 68.5 years [range 47-88]; 14 males [61%]), 18 cases were culture-positive. Nanopore sequencing identified the same cultured organism in all of the culture-positive cases and identified potential pathogens in two culture-negative cases (40%). Nanopore WGS was able to additionally detect the presence of bacteriophages in three samples. The agreements at genus level between culture and 16S Nanopore, Nanopore WGS, and Illumina WGS were 75%, 100%, and 78%, respectively.

CONCLUSIONS

Whole genome sequencing has higher sensitivity and provides a viable alternative to culture and 16S sequencing for detecting potential pathogens in endophthalmitis. Moreover, WGS has the ability to detect other potential pathogens in culture-negative cases. Whilst Nanopore and Illumina WGS provide comparable data, nanopore sequencing provides potential for cost-effective point-of-care diagnostics.

A prospective assessment of cytomegalovirus immune evasion gene transcription profiles in transplant patients with cytomegalovirus infection

BACKGROUND

The cytomegalovirus (CMV) immune evasion genes US3, US6, and US11 may disrupt the host immune response via downregulation of major histocompatibility complex molecules. Transplant recipients with CMV infection were prospectively assessed for immune evasion gene expression.

METHODS

Seventy solid organ transplant patients with CMV infection who were given antiviral therapy were enrolled. Quantitative mRNA levels of US3, US6, and US11 were assessed using real-time polymerase chain reaction assays from peripheral blood mononuclear cells at regular time-points after starting therapy.

RESULTS

High immune evasion mRNA levels were detectable at start-of-therapy (median US3-4.5 log10 copies; US6- 3.7 log10 copies, and US11-3.3 log10 copies/10 cells). With therapy, immune evasion mRNA levels declined exponentially. For example, median calculated US3 half-life was 1.59 days (range 0.74-12.5 days). By day7, US3 mRNA was detectable in 55.7%, US6 in 38.6%, and US11 in 41.4% of patients. Early phase kinetics correlated with outcomes. When adjusted for baseline DNA level, there was a trend to higher mRNA levels in patients who relapsed. Also, detectable mRNA at day 14 after start of therapy was associated with virologic relapse after initial treatment (P<or=0.001 for US3, US6, and US11). For example, if US3 mRNA was still detectable at day 14, then risk of relapse was 84.2% vs. 29.4% if US3 mRNA not detectable at day 14 (P<0.001). This correlation was independent of the DNA viral load.

CONCLUSION

CMV immune evasion gene expression is detectable at high levels in patients with CMV infection and declines exponentially with therapy. Expression levels can be independently correlated with outcomes.

ASSESSING REFRACTIVE OUTCOMES AND ACCURACY OF BIOMETRY IN PHACOVITRECTOMY AND SEQUENTIAL OPERATIONS IN PATIENTS WITH RETINAL DETACHMENT COMPARED WITH ROUTINE CATARACT SURGERY

PURPOSE

To compare refractive outcomes and accuracy of modern optical biometry, swept-source optical coherence tomography, ultrasound biometry, and effect of the macula status in rhegmatogenous retinal detachment managed with either combined phacovitrectomy or sequential vitrectomy and cataract surgery compared with a control, phacoemulsification alone.

METHODS

Retrospective, comparative, consecutive study of 154 eyes; Group 1 underwent phacovitrectomy (n: 70), Group 2 underwent vitrectomy with subsequent cataract surgery (n: 41), and Group 3 underwent cataract surgery alone (n: 43).

RESULTS

No difference in the mean absolute error was found between Group 2 (0.41 ± 0.56) and Group 3 (0.41 ± 0.29); both were superior to Group 1 (0.74 ± 0.57). Between Group 1 and Group 2, no statistically significant difference in the mean absolute error was found between macula-on subgroups (P = 0.057), but this was statistically significant between macula-off subgroups (P = 0.009). Subgroup analysis by biometry showed that the difference in the mean absolute error between macula-off optical biometry Group 1 and Group 2 against our control, Group 3, were not significant (P = 0.078 and P = 0.119, respectively); the mean absolute error was significantly different when considering macula-off ultrasound biometry cases (P < 0.001 and P = 0.038, respectively).

CONCLUSION

All three groups had comparable refractive outcomes when using optical biometry. However, phacovitrectomy macula-off cases had inferior refractive outcomes when the ultrasound biometry had to be used. In macula-off rhegmatogenous retinal detachment, when optical biometry is not reliable, it is preferable to perform sequential surgery rather than phacovitrectomy.

Restructuring emergency eye services during COVID-19 in a tertiary referral centre

BACKGROUND/AIMS

Maintaining emergency eye services is crucial during the COVID-19 pandemic. This article describes the introduction of a new restructured referral pathway to reduce the burden on healthcare providers and create a safe environment.

METHODS

During January and February 2020 (group 1), all appointments were face-to-face with a walk-in eye casualty. The first audit cycle comprised all patients in group 1. The primary audit criteria were discharge rates, referral to subspeciality and reattendance. In April 2020, a remodelled system was implemented in which walk-in attendance ceased and was replaced with telephone triage coupled with digital imaging via NHS email for remote clinical review. Patients requiring further assessment following this triage were invited in for face-to-face appointments. A reaudit was conducted during April-July 2020 (group 2) following implementation of these COVID-19 protocol changes.

RESULTS

In group 1, 2868 appointments (100.0%) were face-to-face and in group 2 4870 (100.0%) appointments were telephone consults that resulted in 2639 (54.2%) face-to-face appointments. The rate of discharge in the first cycle and second cycle were 55.3% and 76.9% respectively (P<0.0001). Furthermore 2298 (47.2%) patients were able to be discharged following telephone consultation in group 2.

CONCLUSIONS

Using this telephone and digital imaging review triage system, the authors have demonstrated a significant reduction in the need for face-to-face reviews. The reduction in avoidable patient face-to-face reviews allows the system to move from saturated to sustainable while increasing accessibility to services for patients who may not be able to present for face-to-face review. This complete audit cycle successfully charts interventions that maximise accessibility, reduce unnecessary hospital visits and deliver safe and prompt management during the pandemic.

Environmental Effect of Fluorinated Gases in Vitreoretinal Surgery: A Multicenter Study of 4,877 Patients

PURPOSE

To investigate the direct contribution to carbon emissions of fluorinated gases used in all vitreoretinal (VR) procedures utilizing gas tamponade and assess the respective carbon footprint of the three different gas delivery systems.

DESIGN

A multicenter, retrospective, environmental impact study.

METHODS

All VR procedures using fluorinated gases between 2017 to 2020 at the Manchester Royal Eye Hospital (MREH) and Birmingham and Midland Eye Centre (BMEC) (the second and third largest VR centers in the UK), and between 2019 to 2020 at the University Hospitals Coventry and Warwickshire (UHCW) were included. CO2 equivalent mass (CO2EM) was calculated from the mass of each gas used, according to the Intergovernmental Panel on Climate Change.

RESULTS

A total of 4877 (1883 SF6 [38.6%], 2096 C2F6 [43.0%], and 897 C3F8 [18.4%]) procedures were analyzed. UHCW and BMEC utilized single-use 30 mL and 75 mL cannisters, respectively. MREH used four cylinders of each gas over 4 years (2 kg SF6, 1 kg C2F6, 1 kg C3F8). Mean CO2EM per patient was: MREH 111.8 kg, BMEC 7.5 kg, and UHCW 2.7 kg. For MREH and BMEC, the CO2EM was 73.4 metric tons annually (if all cases were performed with i) 30 mL: 3.7 tons and ii) cylinders: 148.0 tons, x 40-fold difference), equating to 599,400 (30,500-1.2 million) km travelled by a passenger car. The current use of SF6 in VR surgery accounts for 0.11% of total SF6 use; if 30 mL cylinders were exclusively used in the UK, this could be lowered to 0.01%.

CONCLUSIONS

This study highlights the significant waste associated with large gas cylinders and demonstrated that 30 mL cannisters can lead to a marked reduction in carbon emissions, even after accounting for the increased carbon footprint involved in their manufacture and disposal.

The Role of Subretinal Injection in Ophthalmic Surgery: Therapeutic Agent Delivery and Other Indications

Subretinal injection is performed in vitreoretinal surgery with two main aims, namely, the subretinal delivery of therapeutic agents and subretinal injection of fluid to induce a controlled and localized macular detachment. The growing interest in this technique is mainly related to its suitability to deliver gene therapy in direct contact with target tissues. However, subretinal injection has been also used for the surgical management of submacular hemorrhage through the subretinal delivery of tissue plasminogen activator, and for the repair of full-thickness macular holes, in particular refractory ones. In the light of the increasing importance of this maneuver in vitreoretinal surgery as well as of the lack of a standardized surgical approach, we conducted a comprehensive overview on the current indications for subretinal injection, surgical technique with the available variations, and the potential complications.

Primary retinopexy in preventing retinal detachment in a tertiary eye hospital: a study of 1157 eyes

PURPOSE

Retinopexy is the most common vitreo-retinal procedure performed in the eye emergency department and significantly reduces the risk of a rhegmatogenous retinal detachment (RRD). There are various indications for retinopexy, with the most common being horseshoe-tears (HST). Multiple treatment techniques exist, ranging from slit-lamp laser-retinopexy, indirect laser-retinopexy or cryopexy. We report on our primary retinopexy 6-month RRD rate, repeat retinopexy rate and compare outcomes of different indications and treatment modalities.

METHODS

Retrospective consecutive case series of 1157 patients attending Birmingham and Midlands Eye Centre, UK between January 2017 and 2020.

RESULTS

The RRD rate at 6 months was 3.9%, with 19.1% requiring subsequent retinopexies. Multivariate Cox survival regression analysis showed that significant risk factors for RRD following primary retinopexy included male gender (p = 0.012), high myopia (≤ - 6.00D, p = 0.004), HST (compared to round holes, p = 0.026) and primary cryopexy (compared to slit-lamp laser, p = 0.014). HST was the most common indication for retinopexy (812 [70.2%]) in which 118 (14.5%) had multiple tears. Slit-lamp laser was used in 883 (76.3%) of cases. The rate for subsequent epiretinal membrane peel surgery was 3 (0.3%) and was higher in eyes that required multiple retinopexy procedures (p = 0.035).

CONCLUSION

With our large cohort of patients over three years, we provide additional evidence on the RRD and subsequent retinopexy rate after primary retinopexy. Further retinopexy is a common occurrence, particularly in high-risk retinal tears such as HST. Strict monitoring and prompt follow-up after retinopexy is important to prevent progression to RRD and should be of priority in the clinicians post-retinopexy management plan, particularly in those with associated risk factors.

Volvulus of the liver with intrathoracic herniation

INTRODUCTION

We present a rare case of a liver volvulus, stomach and transverse colon herniating through the diaphragm. This scenario has not been reported previously. We discuss the presentation and management of this interesting case.

CASE HISTORY

A 65-year-old woman with a history of sarcoidosis and recurrent pericardial effusions, treated previously with a subxiphoid pericardial oval window fenestration, presented with acute upper abdominal pain radiating to the chest. High contrast computed tomography showed a volvulus of the liver with consequent venous congestion, and herniation of the liver, stomach and transverse colon through an anterior diaphragmatic defect. With liver perfusion threatened, an urgent laparoscopic repair was performed. The stomach and transverse colon were reduced, and the twisted left lobe of the liver was unrotated and reduced into the abdominal cavity. A double-sided synthetic mesh was used to repair the defect. The patient made an uneventful recovery.

CONCLUSIONS

This is a novel complication of a patient presenting with abdominal pain with a previous history of pericardial window fenestration. A laparoscopic reduction and repair can be performed safely with excellent postoperative results.

Effect of deprivation and ethnicity on primary macula-on retinal detachment repair success rate and clinical outcomes: A study of 568 patients

PURPOSE

Socio-economic deprivation and ethnic variation have been frequently linked to poorer health outcomes. We collected a large series of primary macula-on rhegmatogenous retinal detachment (RRD) cases and analysed the effect of socio-economic deprivation and ethnicity on both six-month retinal re-detachment rate and visual outcomes.

MATERIALS AND METHODS

Retrospective consecutive case series of 568 patients attending Birmingham and Midlands Eye Centre from January 2017-2020. Multiple Indices of Deprivation (IMD) deciles were used for deprivation status and split to two groups: IMD-A (Decile 1-5) and IMD-B (Decile 6-10). The two largest subgroups of ethnicities were compared, White and South Asians (SA).

RESULTS

We report an overall retinal re-detachment rate of 8.5%. IMD-A re-detached significantly more than IMD-B (11.2% vs 6.0% respectively, p = 0.034). No statistical significance was found between White and SA re-detachment rate (9.1% and 5.6% respectively, p = 0.604). SA median age significantly lower at 49 years (IQR: 37-61) compared to White patients at 57 years (IQR: 50-65) (p = <0.001). IMD-A median age of 55 years (IQR: 46-64) was significantly lower to IMD-B median age of 58 years (IQR: 51-65) (p = 0.011). No differences in final visual outcomes were detected across all groups.

CONCLUSION

We demonstrated an increased retinal re-detachment rate in our more deprived patients according to IMD and a younger cohort of SA compared to White ethnicity. Further prospective studies are required to demonstrate the link between socio-economic deprivation and surgical success.

Vitrectomy with air tamponade and cryotherapy for retinal detachment repair without perfluorocarbon use: A UK 12-month prospective case series

INTRODUCTION

Rhegmatogenous retinal detachment (RRD) is commonly managed by pars plana vitrectomy (PPV). Gas tamponade has significant clinical and quality of life factors that affect the patient. Using shorter acting air tamponade, intuitively leads to surgical concern for higher rate of primary detachment. To circumvent this, surgeons advocate the use of perfluorocarbon to maximise sub-retinal-fluid drainage when using air tamponade and/or avoid using cryotherapy due to longer duration for scar formation relative to laser. These steps are a deviation from traditional technique for otherwise routine primary RRD repair and discourages popularisation of using air tamponade despite the benefits to patients.

METHOD

Prospective 12-month, single centre, single surgeon, consecutive study from January to December 2019. Inclusion criteria was as per based on the pneumatic retinopexy versus vitrectomy for retinal detachment: (i) single retinal break or group of breaks, no larger than 1-clock-hour (30°), in detached retina; (ii) all breaks in detached retina lie above the 8 to 4 o'clock meridian; and (iii) breaks or lattice degeneration in attached retina at any location. We excluded PVR formation and RRD in the inferior 4 o'clock hours.

RESULTS

We report primary and final success rate of 96% and 100%, respectively in 23 eyes (22 macular-on and one macular-off) with RRD eyes in a 12-month period. Cryopexy was utilised in 65% patients and in isolation in 23% with no perfluorocarbon use in all eyes.

CONCLUSION

We show cryotherapy can be used safely in AT-RRD without PFCL in RRD fulfilling PIVOT trial criteria with minimal cataract formation and IOP spikes and faster post-operative visual rehabilitation.

Surgical Versus Conservative Management of Acute Appendicitis During the COVID-19 Pandemic: A Single-Centre Retrospective Study

Introduction The COVID-19 pandemic provoked a change to normal surgical practice in the United Kingdom and led to an increase in acute appendicitis (AA) patients being treated conservatively with antibiotics. We aim to analyse the management of patients presenting with AA to our institution during the first wave of the pandemic, comparing surgically and conservatively managed patients. Method All patients presenting to our centre with AA between March and July 2020 were included. Six-month follow-up data were collected retrospectively using electronic records. Patients were categorised into surgically and conservatively managed groups. The primary outcome was the complication rate (post-operative complications vs failure of antibiotic treatment) and the secondary outcomes were length of hospital stay and Alvarado score. Results  Fifty-seven patients (n=57) were admitted with AA, 45.6% (n=26) managed conservatively compared to 54.4% (n=31) treated surgically. Higher complication rates were observed amongst the conservatively managed group, although not found to be statistically significant (16% vs 35%; p=0.131). There was no significant difference in length of hospital stay observed between the two groups (surgical: median, 2; interquartile range, 2-3 vs conservative: median, 3; interquartile range, 2-4). White cell count (WCC) and Alvarado score were higher on admission in the surgical group with statistical significance (p=0.012 and p=0.028, respectively). Conclusions COVID-19 has led to a significant cohort of conservatively managed AA patients in the United Kingdom. We propose a stratification pathway based on clinical severity, Alvarado score and imaging to facilitate safe selection for conservative management of AA, in order to reduce failure of treatment rates in this patient group. Further UK-based studies will add to the evidence-based surrounding safe management of AA with conservative treatment.

Refractive Outcomes of Phacovitrectomy in Retinal Detachment Compared to Phacoemulsification Alone Using Swept-Source OCT Biometry

BACKGROUND AND OBJECTIVE

To assess the refractive outcomes in patients who underwent combined phacovitrectomy for retinal detachment compared to phacoemulsification and intraocular lens (IOL) implant utilizing newer swept-source optical-coherence-tomography (SS-OCT) biometry and determine the requirement of an adjustment factor for superior predicted refractive outcomes.

PATIENTS AND METHODS

Retrospective study of 95 eyes: 52 eyes that underwent phacovitrectomy and 43 eyes with phacoemulsification only that served as the control group. Mean refractive error (ME) and mean absolute error (MAE) were used to compare the groups.

RESULTS

No statistically significant postoperative refractive shift was found between phacoemulsification and phacovitrectomy eyes for (1) ME (0.05 D [± 0.51 diopters (D)] and (0.03 [± 0.73 D], respectively; P = .348), (2) MAE (0.41 D ± 0.29 D and 0.60 ± 0.44 D, respectively), or (3) MAE of the control compared to macula-on/off eyes (P = .160 and P = .078, respectively).

CONCLUSION

The authors do not recommend an adjustment factor for IOL selection when utilizing SS-OCT biometry, as it provided refractive outcomes superior to those found in previous studies utilizing a partial coherence interferometry system. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:432-437.].

Effect of demographics and ethnicity on laser retinopexy in preventing retinal detachment in a tertiary eye hospital in 812 eyes

PURPOSE

To investigate different baseline characteristics, clinical indications, repeat retinopexy rate, and 6-month detachment rate of primary laser retinopexy across different ethnicities.

METHOD

Retrospective, single-centre, consecutive comparative study, looking at all patients who had primary laser retinopexy between January 2017 and 2020. Multivariate Cox survival [reporting hazard ratio (HR)] and binary logistic regression (reporting odds ratio) analyses were performed to investigate differences between ethnicities with age, gender, operator level (vitreoretinal or general ophthalmologist) and high myopia status (≤-6.0 Dioptres) as covariates.

RESULTS

We report on 812 patients in three ethnicities: Black [69 (8.5%)], South Asian [SA, 156 (19.2%)] and White [587 (72.3%)] with overall 6-month detachment rate of 31 (3.8%). Rate for subsequent retinopexies was Black: 12 (17.4%), SA: 15 (9.6%) and White: 131 (22.3%), p = 0.002. Multivariate Cox survival regression analysis found no difference in detachment rate between ethnicities. South Asian (SA) had lower repeat retinopexy rate than White patients [HR, 0.40 (95% confidence interval [CI], 0.22-0.71, p = 0.002)]. Multivariate binary logistic regression found that Black and SA patients compared with White, have the following: (i) higher proportion of round holes relative to horseshoe tears [OR, 2.31 (95% CI, 1.19-4.49, p = 0.014) and OR, 2.06 (95% CI, 1.25-3.40), p = 0.004, respectively] and (ii) higher proportion of high myopia [OR, 2.99 (95% CI, 1.20-7.46, p = 0.019) and OR, 2.35 (95% CI, 1.11-4.96), p = 0.025, respectively]. Ethnic minorities were younger than White patients: SA [43, interquartile range (IQR), 28-61], Black (49, IQR, 35-57) and White (61, IQR, 54-67 years, p < 0.001) and had more indirect and 360 retinopexy compared with slit lamp (p < 0.001).

CONCLUSION

We demonstrate a significant difference in baseline characteristics, retinal tear morphology and treatment course between the ethnic groups. Further studies are necessary to investigate the genetic and biological differences that may influence these variations and may help to allow for more targeted health care.

Neovascular Glaucoma: An Update

Neovascular glaucoma (NVG) is a severe type of secondary glaucoma with devastating complications and generally poor visual prognosis. NVG is defined by the development of pathological neovessels over the iris and the iridocorneal angle that can block the outflow of aqueous humor, causing elevation of intraocular pressure (IOP). The pathogenesis of NVG is, in most cases, associated with ischemia of the posterior segment, which is most frequently associated with proliferative diabetic retinopathy or central retinal vein occlusion. The advanced stages of NVG are by iris and angle neovascularization, angle, and extremely high IOP, accompanied by ocular pain and poor vision. The therapeutic approach of NVG is based on the reduction of retinal ischemia by panretinal photocoagulation. Intravitreal anti-VEGF administration can contribute to the regression of neovascularization, and topical and systemic medications may be necessary for IOP control. However, if medical treatment with these agents is not enough, surgical procedures may be required to lower IOP and prevent glaucomatous optic neuropathy. Early and prompt diagnosis, with identification of the underlying etiology, can improve IOP control and final visual outcome. The aim of this study is to review current knowledge of the pathogenesis and management of NVG.

The impact of COVID-19 on primary retinopexy in preventing retinal detachment in a tertiary eye hospital emergency department

PURPOSE

To review the effect of COVID-19 on rhegmatogenous retinal detachment (RRD) rate following primary retinopexy.

METHODS

Retrospective consecutive case series of 183 patients attending Birmingham and Midlands Eye Centre undergoing primary retinopexy (cryotherapy and laser) between March 23rd to June 30th in 2019 (Group 1) and 2020 (Group 2).

RESULTS

In total we reviewed 183 retinopexies, 122 in Group 1 and 61 in Group 2, a reduction of 50%. In Group 2 compared to Group 1, we showed a significant difference in characteristics of patients having primary retinopexy with an increase in proportion of male patients from 50 (41.0%) to 39 (63.9%) (p = 0.005), increase in high myopes from 1 (0.8%) to 4 (6.6%) (p = 0.043), more slit lamp laser retinopexy from 83 (68.0%) to 52 (85.2%) (p = 0.013) and less cryopexy from 21 (17.2%) to 2 (3.3%) (p = 0.008). In Group 2, primary retinopexy resulted in significantly more 3-month RRD rate 1 (0.8%) to 5 (8.2%) (p = 0.016). There were no changes in number of patients requiring further retinopexy (p = 1.000).

CONCLUSION

This study demonstrates a reduction of primary retinopexy, an increased risk for RRD following primary retinopexy and a significant shift in type of primary retinopexy performed, demographics, operator and change in characteristics of type of retinal break observed during this pandemic. This study contributes to the growing literature of the secondary effects of the COVID-19 pandemic on other aspects of healthcare that is not just limited to the virus itself.

Interferometric single-shot parity measurement in InAs-Al hybrid devices

The fusion of non-Abelian anyons is a fundamental operation in measurement-only topological quantum computation1. In one-dimensional topological superconductors (1DTSs)2-4, fusion amounts to a determination of the shared fermion parity of Majorana zero modes (MZMs). Here we introduce a device architecture5 that is compatible with future tests of fusion rules. We implement a single-shot interferometric measurement of fermion parity6-11 in indium arsenide-aluminium heterostructures with a gate-defined superconducting nanowire12-14. The interferometer is formed by tunnel-coupling the proximitized nanowire to quantum dots. The nanowire causes a state-dependent shift of the quantum capacitance of these quantum dots of up to 1 fF. Our quantum-capacitance measurements show flux h/2e-periodic bimodality with a signal-to-noise ratio (SNR) of 1 in 3.6 μs at optimal flux values. From the time traces of the quantum-capacitance measurements, we extract a dwell time in the two associated states that is longer than 1 ms at in-plane magnetic fields of approximately 2 T. We discuss the interpretation of our measurements in terms of both topologically trivial and non-trivial origins. The large capacitance shift and long poisoning time enable a parity measurement with an assignment error probability of 1%.

Vitreoretinal specialists compared with residents on outcomes of primary laser retinopexy in preventing retinal detachment in 958 eyes

Objective

Retinal tears are the most common vitreoretinal (VR) emergency and retinopexy aims to reduce the risk of rhegmatogenous retinal detachment (RRD). Currently retinal laser is a required competence by the Royal College of Ophthalmologists for residents. We report 6-month detachment rate and repeat retinopexy rate of VR specialists compared with residents.

Methods and analysis

A retrospective, consecutive study of 958 eyes undergoing primary laser retinopexy (slit lamp or indirect laser) from January 2017–2020 was divided into training level by operator: specialty training (ST) 2–3, ST4–5, ST6–7 and VR specialists.

Results

We report an overall 6-month RRD rate in 32/958 (3.3%) (ST2–3: 9/221 (4.1%), ST4–5: 15/373 (4.0%), ST6–7: 2/72 (2.8%) and VR specialists: 6/292 (2.1%)). We additionally report a repeat retinopexy rate of 189/958 (19.7%), (ST2–3: 44/221 (19.9%), ST4–5: 80/373 (21.4%), ST6–7: 16/72 (22.8%) and VR specialists: 49/292 (16.8%)]). Multivariable Cox survival regression analysis showed significant risk factors for developing RRD include male gender (p=0.018), high myopia (≤−6.00 Dioptres, p=0.004), ST2–3 (p=0.022) and ST4–5 (p=0.040) (relative to VR specialists) and by ST6–7, no significance was found (p=0.151). Significantly higher repeat retinopexy rates were associated with horseshoe tears (relative to round holes, p<0.001) and high myopia (p=0.026) with no difference between different training levels.

Conclusion

There was a decreasing trend in RRD rate following primary retinopexy with increase in training. Although junior residents had a higher RRD rate than VR specialists, it was still favourable relative to other large case series. While there was no difference in subsequent laser retinopexy rate between training levels, the retreatment rate was associated with the type of tear and high myopia.

Unexplained visual loss in retinal detachment repair: comparing gas, silicone oil and heavy silicone oil by multivariable regression

PURPOSE

To measure the proportion of unexplained and all causes of visual loss following primary rhegmatogenous-retinal-detachment (RRD) repair, comparing gas tamponade (SF₆, C₂F₆, C₃F₈), silicone oil (SO, 1000cs and 5000cs) and heavy silicone oil (Densiron).

METHODS

Retrospective, continuous, comparative study from 01/1/2017-31/5/2021. All primary RRDs were included after successful removal of SO and Densiron. Primary failures were excluded. Visual loss was defined as reduction of ≥0.30 logMAR units. Multivariable binary-logistic and linear regression models to compare tamponade, and all cases of unexplained visual loss and logMAR gain were performed. Covariates included age, ocular co-morbidities, pre-op vision, macula-status, high-myopia, giant-retinal-tear (GRT), perfluorocarbon-use, combined buckle/PPV, PVR-C, retinectomy, tamponade agent and post-operative lens status.

RESULTS

Of 1,012 primary RRDs, we found an incidence of unexplained visual loss in 15/1012 (1.5%, SF₆:1/341[0.3%], C₂F₆:4/338[1.2%], C₃F₈:2/239[0.8%], Densiron:0/33[0.0%], SO-1000cs:5/43[11.6%] and SO-5000cs:3/18[16.7%]), and visual loss of all causes in 57/1012 (5.6%, SF₆:13/341[3.8%], C₂F₆:14/338[4.1%], C₃F₈:15/239[6.3%], Densiron:2/33[6.1%], SO-1000cs:9/43[20.9%] and SO-5000cs:4/18[22.2%]). On multivariable binary-logistic regression, we report that macula-on RRD (Odds-Ratio[OR]5.7,95% Confidence-interval[CI]1.2-28.2, p=0.032), GRT (OR35.0,CI 2.0-617.3, p=0.015), combined buckle/PPV (OR37.7,CI 2.0-711.4, p=0.015), SO1000cs (OR86.6,CI 5.6-1,348.0), p=0.001) and 5000cs (OR37.2,CI 1.3-1,101.5, p=0.036) (Reference-tamponade:SF₆) were associated with unexplained visual loss. Duration of oil tamponade was not linked to increase in unexplained visual loss (p=0.569).

CONCLUSIONS

Correlation between SO in detachment repairs and unexplained visual loss has been established, however incidence with HSO has not been compared to other agents. This study demonstrates that although SO was linked with risk-adjusted increased unexplained visual loss relative to gas tamponade, no such association was found for Densiron, on multivariable analysis.