Anatomical and functional features of photic retinopathy: a spectral domain optical coherence tomography-based longitudinal study.

BACKGROUND: Photic retinopathy may lead to permanent foveal structural injury, leading to irreversible visual acuity loss. METHOD: This prospective observational study evaluated 51 eyes of 30 patients with photic retinopathy. Optical coherence tomography (OCT) imaging was performed for all the eyes at baseline and final follow-up. All the eyes showed a focal outer retinal defect on spectral-domain OCT (SD-OCT) at the junction of the inner and outer photoreceptor segments. SD-OCT was used to measure central macular thickness, maximum horizontal dimension of the defect, maximum defect thickness, and the photic retinopathy index (PRI) through the foveal raster scan. RESULTS: Although PRI improved significantly at the final follow-up from baseline with a 17% improvement in PRI after a period of 6 months in photic retinopathy eyes, visual acuity declined for 14% of the patients and was stable for 84%. There was mild correlation of visual acuity with baseline PRI. Baseline PRI was significantly higher in eyes with poorer presenting visual acuity (VA). In total, 33.3% of the eyes showed partial ellipsoid zone recovery at 6 months. The area under curve of the receiver operator characteristic curve for partial ellipsoid zone recovery with the mean baseline PRI as the independent variable was poor at 0.612. CONCLUSION: OCT-based ultrastructural features in photic retinopathy seem to have poor correlation with presenting or final visual acuity. To the best of our knowledge, this is the largest study on longitudinal OCT evaluation of photic retinopathy eyes in literature.

Invasive Fungal Sinusitis in Patients With Coronavirus Disease 2019 Seen in South India.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has a vast array of presentations and associations with neuro-ophthalmic diseases. There has been a recent surge in ophthalmic manifestations secondary to fungal sinus infections in India especially in diabetic patients who were given systemic steroids. We present our COVID-19-related cranial neuropathies presenting in our clinic. METHODS: This is a retrospective case series of 10 patients affected with COVID-19 disease and who presented with cranial nerve palsies at the neuro-ophthalmic department of a tertiary eye care hospital in South India. An analysis of electronic medical records data was performed, including their comorbidities, symptoms, cranial nerves involved, ocular and neuroimaging findings, site of lesion, etiology, and prognosis. RESULTS: Most of the patients (7 of 10) presented with multiple cranial nerve palsies (MCNP) with poor visual acuity. 2 of the 10 cases succumbed to death due to the intracranial involvement. All MCNP cases had uncontrolled diabetes with a history of systemic steroids, and neuroimaging of these cases showed sinusitis of varying severity most of which were suggestive of fungal invasive type. CONCLUSION: Our study emphasizes the need to screen for fungal involvement in COVID-19 cases presenting with MCNP especially on diabetic patients on systemic steroids so that an early diagnosis may reduce visual loss and mortality. Physicians treating COVID-19 cases need to be aware of this dreadful complication.

Retinal manifestations in patients with SARS-CoV-2 infection and pathogenetic implications: a systematic review.

INTRODUCTION: The pandemic of COVID-19 has been caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Apart from respiratory malfunction, COVID-19 causes a system-wide thromboembolic state, leading to serious cardiovascular, cerebrovascular and peripheral vascular manifestations. However, our knowledge regarding retinal manifestations due to systemic COVID-19 is minimal. This systematic review has comprehensively summarized all retinal manifestations secondary to COVID-19 disease recorded till date since the beginning of the pandemic. METHODS: All studies published till November 27, 2020, which have reported retinal manifestations in COVID-19 patients were systematically reviewed using the PRISMA statement. RESULTS: We included 15 articles: 11 case reports and four cross-sectional case series. The most commonly reported manifestations which did not affect visual acuity were retinal hemorrhages and cotton wool spots. The most common vision threatening manifestation was retinal vein occlusion with associated macular edema. Rarely, patients may also present with retinal arterial occlusions and ocular inflammation. These manifestations may occur from as soon as within a week after the onset of COVID-19 symptoms to more than 6 weeks after. CONCLUSION: Mostly causing milder disease, COVID-19 may however lead to severe life-threatening thromboembolic complications, and systemic antithrombotic therapy has been suggested as a prophylactic and therapeutic management strategy for patients affected with serious systemic disease. However, both sick and apparently healthy patients may suffer from various retinal complications which may lead to loss of vision as well. No consensus regarding management of retinal complications with anticoagulants or anti-inflammatory medications have been proposed; however, they may be tackled on individual basis.

Clinico-demographic profile and outcomes of 25-gauge vitrectomy in advanced stage 5 retinopathy of prematurity.

BACKGROUND: Stage 5 retinopathy of prematurity is a difficult condition to treat despite technological advances in vitreous surgery. METHODS: A retrospective chart review of all consecutive cases of stage 5 ROP was performed between December 2016 and December 2018, and 21 babies were included for assessment of surgical outcomes using a modified vitrectomy technique. Data extracted from documents included demography, ROP screening status, preoperative prophylactic therapy, clinical presentation, surgery performed, and postsurgical outcomes. RESULTS: Out of the 21 babies, ophthalmologist screening was done in 42.9%. Mean birth weight was 1185 ± 222.4 g with a mean gestational age of 29.86 ± 2.0 weeks and mean post-menstrual age of 44.55 ± 9.82 weeks. Lesser than stage 5 disease was seen in 16.7% of eyes and they were managed accordingly. Seventy percent of babies had bilateral disease. 21 eyes underwent 25-gauge pars plicata vitrectomy using a modified technique. After an average follow-up duration of 6.33 ± 2.18 months, the final macular attachment rate was 19%. Anteriorly closed-posteriorly closed type configuration of retinal detachments had a poorer outcome. Fix and follow visual acuity was achieved in 23.8% of eyes, while 57.1% of eyes had a perception of light. CONCLUSIONS: Management of stage 5 ROP is mostly surgical; however, the risk of ending up with a poor vision or vision loss is high, irrespective of whether surgery is performed. The modified surgical technique with a spacer described in this study may help in better manipulation of instruments inside the vitreous cavity.

Two-staged surgery as an alternative to buckle-vitrectomy for rhegmatogenous retinal detachment complicated by choroidal detachment.

AIM: To evaluate the outcome and safety profile of short-term perfluorocarbon liquids (PFCL) tamponade in comparison with buckle-vitrectomy in case of rhegmatogenous retinal detachment (RRD) associated with choroidal detachment (CD). METHODS: Records of patients who underwent surgery for RRD/CD from January 2016 to July 2019 were reviewed retrospectively. The patients were allocated into two groups-group 1 patients underwent buckle-vitrectomy, while those in group 2 underwent a two-staged vitrectomy with short-term (5 days) PFCL tamponade. RESULTS: The study included 33 eyes (33 patients) with mean age of 50.3 ± 17.2 years. Group 1 included 15 patients, while group 2 included 18. The pre-operative characteristics were similar in both the groups. The mean pre-operative intraocular pressure in group 1 and 2 was 9.1 ± 4.0 and 8.6 ± 5.2 mmHg, respectively (p = 0.755). Retinal re-attachment after single surgery was achieved in 10 (66.7%) and 14 eyes (77.8%), respectively. All the eyes achieved retinal re-attachment after repeat surgery in both the groups (1.40 vs 1.39 surgeries, p = 0.963). Post-surgery visual improvement was seen in 13 (86.7%) and 17 eyes (94.4%), respectively (p = 0.579). Final visual acuity of ≥ 6/60 was obtained in 7 (46.7%) and 9 eyes (50.0%), respectively (p > 0.999). None of the patients needed retinectomy during repeat surgery. None of the patients experienced exaggerated inflammation or intractable raised IOP spike which could not be controlled with medications. CONCLUSION: Surgical outcomes were similar in both the groups. No clinically apparent toxicity was seen with post-operative short-term PFCL tamponade. Two-staged surgery is a good alternative to buckle-vitrectomy for eyes with RRD associated with CD.

Ten-year trends in the incidence, clinical profile and outcomes of acute-onset endophthalmitis following combined pars plana vitrectomy and sutureless, glueless and flapless scleral fixation of intraocular lenses.

PURPOSE: To evaluate the frequency and outcomes of acute-onset endophthalmitis following combined pars plana vitrectomy and scleral fixation of intraocular lens. METHODS: We evaluated patients undergoing a sutureless, glueless, flapless technique of scleral fixation of intraocular lenses (SFIOL) implantation for various causes of aphakia and documented the clinico-demographic data, microbiological profile and final outcome after acute endophthalmitis in this cohort of eyes. RESULTS: The frequency of suspected acute endophthalmitis diagnosed post-surgery was 0.112% (4/3541 eyes), with culture-positive endophthalmitis frequency being 0.028% (1 eye), showing growth of Pseudomonas aeruginosa. Mean age of patients with endophthalmitis was 51.75 ± 9.28 years, and mean interval between surgery and acute endophthalmitis presentation was 10.25 ± 9.6 days. Patients were managed with intravitreal antibiotics with or without core vitrectomy. Visual acuity of patients increased from baseline 1.43 ± 0.32 logMAR (Snellen equivalent = 6/150) to 0.79 ± 0.16 logMAR (Snellen equivalent = 6/36) after an average follow-up of 11 ± 2 weeks. CONCLUSION: Endophthalmitis is a rare complication following SFIOL surgery, and all ophthalmic surgeons must be aware of this inadvertent possibility, since SFIOLs are gaining wider acceptability recently. Moreover, these cases of endophthalmitis may show a different pattern of microorganisms than post-cataract surgery endophthalmitis; however, with prompt diagnosis and effective timely management, favorable outcomes can be achieved.

Clinical presentation and prognostic factors affecting surgical outcomes of secondary macular holes after retinal vein occlusions.

PURPOSE: To describe clinical presentation, morphological features and surgical outcomes of macular hole (MH) secondary to retinal vein occlusion (RVO). METHOD: This prospective interventional study evaluated eight eyes with atypical MH (secondary to RVO) and data regarding medical management, pars plana vitrectomy, postoperative anatomical hole closure, visual acuity improvement, morphological features of hole were noted till the last follow-up. RESULTS: Eight eyes with full-thickness MH in an RVO eye were followed-up for a minimum period of 3 months postoperatively. Five subjects had a RVO episode which occurred more than 6 months before the onset of the recent symptoms (Group 1; 4 branch RVO and 1 central RVO), and 3 subjects had a recent onset branch RVO within 6 months (Group 2). All FTMH cases except one showed closure at the last follow-up. Visual acuity of all eyes improved from 0.91 ± 0.57 logMAR to 0.5 ± 0.3 logMAR (p = 0.093). At baseline, visual acuities of the two groups had no significant difference. Postoperatively, group 1 holes had better visual prognosis, than Group 2 holes, further substantiated by persistence of subretinal fluid in Group 2 eyes till last follow-up. Minimum hole diameter was higher in the recent RVO group, although anatomical closure was obtained in all of these eyes. Most holes had favorable morphological hole features like raised configuration with rounded edges. CONCLUSION: In the presence of favorable morphological features, secondary macular holes associated with retinal vein occlusion may show optimal outcomes after surgery. It is not clear whether acutely created holes in recent onset RVO should be operated early. Older holes may have better prognosis.

Transesophageal Echocardiographic Assessment of Pulmonary Artery-to-Ascending Aorta Ratio for the Detection of Pulmonary Hypertension in Cardiac Surgical Patients.

OBJECTIVE: The objective of the study was to investigate if the main pulmonary artery (mPA)-to-ascending aorta (AscAo), (mPA:AscAo) ratio could serve as a screening tool in identifying pulmonary artery hypertension (PAH). DESIGN: A prospective observational study. SETTING: Tertiary care center, university hospital. PARTICIPANTS: Fifty-four adult patients undergoing off-pump coronary artery bypass grafting surgery (OPCAB). INTERVENTIONS: mPA and AscAo transverse diameters were measured by transesophageal echocardiography (TEE) and the mean pulmonary arterial pressures (mPAP) were recorded simultaneously using a pulmonary artery catheter. MEASUREMENTS AND MAIN RESULTS: mPA:AscAo ratio demonstrated significant linear correlation with mPAP measured by pulmonary artery catheterization (ie, r = 0.61, confidence interval [CI] = 0.5352-0.6736, p < 0.0001). Receiver operating characteristic curves were performed to evaluate sensitivity and specificity of mPA:AscAo ratio ≥1 for diagnosing PAH (mPAP ≥25 mmHg). Area under the curve for mPA:AscAo ratio was 0.91 (95% CI, 0.869-0.936, p < 0.0001), with a sensitivity of 84.27%, specificity of 83.92%, positive-predictive value of 87.6% and negative-predictive value of 81.1% for a mPAP ≥25 mmHg. CONCLUSIONS: The ratio of mPA:AscAo is a simple, reliable, and reproducible method that can be obtained through TEE, which guides the clinician to screen patients with PAH.

Outcome of 2 cc pure sulfur hexafluoride gas tamponade for macular hole surgery.

BACKGROUND: Isoexpansile concentrations of intraocular gases are typically used as tamponading agent in macular hole surgery. Using a small volume of the pure form of these gases may achieve the same result without increasing the incidence of postoperative complications. The purpose of this study was to evaluate the anatomical and visual outcomes following macular hole surgery with 2 cc pure (100 %) sulfur hexafluoride (SF6) gas tamponade. METHODS: A retrospective study of eyes with idiopathic macular holes that underwent 23-gauge pars plana vitrectomy with 2 cc pure SF6 gas tamponade. Macular hole surgery was performed alone or in combination with phacoemulsification in eyes with cataract. Preoperative and postoperative data including best corrected visual acuity recorded in LogMAR units, slit-lamp biomicroscopy, and optical coherence tomography were analysed. Surgical complications were also recorded. RESULTS: Seventy six eyes of seventy five patients were analysed. A closure rate of 100 % was achieved with reoperation in 4 eyes. There was a significant improvement in best-corrected visual acuity from a mean of 0.65 LogMAR preoperatively to 0.36 at 6 months (p value 0.004). Forty five (59 %) eyes gained at least 2 lines on the Snellen visual acuity chart. Postoperative elevation in intraocular pressure (≥30 mmHg) was documented in 3 eyes (4 %). CONCLUSION: Macular hole surgery with 2 cc pure SF6 gas tamponade achieved a high success rate with a low incidence of complications. The smaller volume of gas required makes it a cheaper technique.

Direct observation of metal-insulator transition in single-crystalline germanium telluride nanowire memory devices prior to amorphization.

Structural defects and their dynamics play an important role in controlling the behavior of phase-change materials (PCM) used in low-power nonvolatile memory devices. However, not much is known about the influence of disorder on the electronic properties of crystalline PCM prior to a structural phase-change. Here, we show that the application of voltage pulses to single-crystalline GeTe nanowire memory devices introduces structural disorder in the form of dislocations and antiphase boundaries (APB). The dynamic evolution and pile-up of APBs increases disorder at a local region of the nanowire, which electronically transforms it from a metal to a dirty metal to an insulator, while still retaining single-crystalline long-range order. We also observe that close to this metal-insulator transition, precise control over the applied voltage is required to create an insulating state; otherwise the system ends up in a more disordered amorphous phase suggesting the role of electronic instabilities during the structural phase-change.

Plasmonic color palettes for photorealistic printing with aluminum nanostructures.

We introduce the first plasmonic palette utilizing color generation strategies for photorealistic printing with aluminum nanostructures. Our work expands the visible color space through spatially mixing and adjusting the nanoscale spacing of discrete nanostructures. With aluminum as the plasmonic material, we achieved enhanced durability and dramatically reduced materials costs with our nanostructures compared to commonly used plasmonic materials such as gold and silver, as well as size regimes scalable to higher-throughput approaches such as photolithography and nanoimprint lithography. These advances could pave the way toward a new generation of low-cost, high-resolution, plasmonic color printing with direct applications in security tagging, cryptography, and information storage.

Embedded plasmonic nanomenhirs as location-specific biosensors.

We introduce a novel optical biosensing platform that exploits the asymmetry of nanostructures embedded in nanocavities, termed nanomenhirs. Upon oblique illumination using plane polarized white light, two plasmonic resonances attributable to the bases and the axes of the nanomenhirs emerge; these are used for location-specific sensing of membrane-binding events. Numerical simulations of the near field distributions confirmed the experimental results. As a proof-of-concept, we present a model biosensing experiment that exploits the dual-sensing capability, the size selectivity offered by the sensor geometry, and the possibility to separately biochemically modify the nanomenhirs and the nanocavities for the specific binding of lipid membrane structures to the nanomenhirs.

Lethal mycotic pseudoaneurysm presenting as isolated sixth nerve palsy.

Pseudoaneurysm of the internal carotid artery caused by skull base osteomyelitis (SBO) is a lethal condition seen in immunocompromised patients, predominantly those with diabetes mellitus. Cranial nerve involvement is a common complication and generally indicates a poor prognosis. We report the case of a 62-year-old diabetic patient who presented with isolated sixth cranial nerve palsy. She had uncontrolled blood sugar levels and high erythrocyte sedimentation rate, and she suffered from pyelonephritis. Neuroimaging detected SBO with multiple secondary mycotic pseudoaneurysms prominent at the petrocavernous junction. Ischemia is the most common etiology for an isolated abducens nerve palsy, but in certain cases neuroimaging is warranted to prevent life-threatening complications. This case highlights the importance and urgency of identifying and managing such conditions.

A Rare Case of Familial Methemoglobinemia with Congenital Heart Disease.

Methemoglobinemia is a rare dyshemoglobin disorder which can either be congenital or acquired. Dyshemoglobin disorders can be asymptomatic or symptomatic. We narrate the case of a 12-year-old girl who presented with a fever, cough, and oxygen saturation of 85%. She was diagnosed with COVID-19, along with a large atrial septal defect and pulmonary arterial hypertension. Arterial blood gas analysis revealed normal partial pressure of oxygen and on 100% exposure to oxygen, blood color turned chocolate brown. After the resolution of COVID-19 in 10 days, the patient was treated with oral ascorbic acid and successful atrial septal defect repair. It is important to suspect dyshemoglobin disorder in a patient who presents with hypoxia/hypoxemia.

Mixed cryoglobulinaemia vasculitis secondary to marginal zone lymphoma in a patient with end-stage renal failure on haemodialysis.

Cryoglobulinaemia vasculitis can present with a variety of symptoms and there is limited data on the incidence and presentation of cryoglobulinaemia vasculitis in haemodialysis patients. We report a case of a 63-year-old male who had a series of presentations with rash, visual changes, abdominal pain, weight loss, fevers and digital ischaemia. This is on a background of a congenital single kidney with end-stage renal failure secondary to diabetes and hypertension, receiving haemodialysis for nearly 5 years. He initially experienced a leukocytoclastic vasculitis rash confirmed on skin biopsy, followed by multiple hospital presentations for undifferentiated abdominal pain and fever of unknown source. Jejunal biopsy revealed intestinal vasculitis. His peripheral blood flow cytometry and bone marrow biopsy were consistent with marginal zone lymphoma (indolent subtype, IgM kappa clone). Further testing revealed a type II cryoglobulinaemia consisting of an IgM kappa monoclonal band with polyclonal IgG (cryocrit 5%). A diagnosis of cryoglobulinaemia vasculitis was established and he was treated with pulsed methylprednisolone and rituximab therapy. However, after receiving three doses of rituximab the patient developed a presumed vasculitis-associated pulmonary haemorrhage for which he received treatment with five sessions of plasma exchange. His symptoms resolved and cryocrit reduced to < 1% after his final dose of rituximab. The clinical features of cryoglobulinaemia may be difficult to detect in chronic haemodialysis patients and vigilance is required.

Comparison of glaucomatous from non-glaucomatous optic neuropathy using Bruch's membrane opening minimum rim width optical coherence tomography measurements.

Purpose: To compare glaucomatous from non-glaucomatous optic atrophy using optical coherence tomography (OCT) based on the measurement values of Bruch's membrane opening minimum rim width (BMO-MRW), which is a difficult task otherwise due to their varied course of disease progression, treatment protocols, and systemic association to visual impairment. Methods: This study was conducted in 40 eyes, comprising 20 eyes with non-glaucomatous optic neuropathy (NGON) and 20 eyes with glaucomatous optic neuropathy (GON). All patients underwent a complete ophthalmic examination followed by an OCT optic disc scan to calculate the measurement of BMO-MRW. Results: The 5-fold cross-validated area under the curve for GON versus NGON from logistic regression models was 0.95 (95% confidence interval [CI]: 0.86-1.00) using BMO-MRW values from all sectors. The results revealed that the measurements were significantly lesser in GON than in NGON patients. Conclusion: Hence, OCT-based BMO-MRW values could be used as an additional test to compare glaucomatous with non-glaucomatous optic neuropathy patients, especially in cases of high clinical suspicion.

Evaluating LDL-C control in Indian acute coronary syndrome (ACS) patients- A retrospective real-world study LDL-C control in ACS.

Background: Low-density lipoprotein-cholesterol (LDL-C) is an independent risk factor for atherosclerotic cardiovascular disease (ASCVD) progression. Although lipid lowering therapies remain the cornerstone of secondary ACSVD prevention, there exists residual dyslipidemia. The current study aimed to evaluate the real-world experience related to the treatment patterns and LDL-C control in Indian Acute Coronary Syndrome (ACS) patients. Methods: This was a real-world, descriptive, retrospective, observational, and multicentric study conducted across India. The data was collected for 1 year following the ACS event. The change in the levels of LDL-C from the baseline to the follow-up visits and the control of LDL-C, the change in lipid profile, lipoprotein levels, treatment patterns for lipid-lowering, and tolerability of existing treatments were evaluated. Results: Overall, 575 patients were included from 11 centers across India. The mean age of the patients was 52.92 years, with male predominance (76.35%). Although there was a significant reduction in the mean levels of LDL-C from the baseline [(122.64 ± 42.01 mg/dl to 74.41 ± 26.45 mg/dl (p < 0.001)], it was observed that despite high-intensity statin therapy, only 20.87% patients managed to achieve target LDL-C of <55 mg/dL and 55.65% were unable to reach LDL-C levels of <70 mg/dl one year after the event. Six patients reported adverse events without treatment discontinuation. Conclusion: The majority of the patients received high-intensity statins and did not attain target LDL-C levels, suggesting LDL-C control after an ACS event requires management with novel therapies having better efficacy as recommended by international and national guidelines.

Participant Perceptions in a Long-term Clinical Trial of Autosomal Dominant Polycystic Kidney Disease.

Rationale & Objective: The development of new therapies for autosomal dominant polycystic kidney disease requires clinical trials to be conducted efficiently. In this study, the factors affecting the recruitment and retention of participants enrolled in a 3-year randomized controlled trial in autosomal dominant polycystic kidney disease were investigated. Study Design: Qualitative study. Setting & Participants: All participants (N=187) were invited to complete a 16-item questionnaire at the final study visit of the primary trial. Participants were recruited to complete a semistructured interview using purposeful sampling according to age, self-reported gender, and randomization group. Analytical Approach: Descriptive statistics were used for demographic data and questionnaires. The interview transcripts underwent inductive thematic coding. Results: One hundred and forty-six of the 187 randomized participants (79%) completed the post-trial questionnaire, and 31 of the 187 participants (21%) completed the interview. Most participants (94%) rated their global satisfaction with the trial as high (a score of 8 or more out of 10). Altruism, knowledge gain, and access to new treatments were the main motivators for recruitment. The main reasons for considering leaving the study were concerns about the risk of intervention and family or work issues. Strategies that favored retention included flexibility in attending different study sites, schedule flexibility, staff interactions, and practical support with parking and reminders. The main burden was time away from work with lost wages, and burden associated with magnetic resonance imaging scans and 24-hour urine output collections. Limitations: The study population was restricted to participants in a single nondrug clinical trial, and the results could be influenced by selection and possible social desirability bias. Conclusions: Participants reported high levels of satisfaction that occurred as a function of the trial meeting participants' expectations. Furthermore, retention was a balance between the perceived benefits and burden of participation. Consideration of these perspectives in the design of future clinical trials will improve their efficiency and conduct. Plain-Language Summary: Advances in the clinical practice of autosomal dominant polycystic kidney disease (ADPKD) require affected individuals to voluntarily participate in long-term multicenter randomized controlled trials (RCTs). In this qualitative post hoc study of a 3-year RCT of increased water intake in ADPKD, altruism, knowledge gain, and access to a nondrug treatment positively influenced the decision to volunteer. Ongoing participation was enabled by building flexibility into the study protocol and staff prioritizing a participant's needs during study visits. Although participants completed the required tests, most were considered burdensome. This study highlights the importance of incorporating protocol flexibility into trial design; the preference for interventions with a low risk of adverse effects; and the urgent requirement for robust surrogate noninvasive biomarkers to enable shorter RCTs in ADPKD.