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Jupiter’s moon Callisto is exposed to a highly dynamic magnetospheric environment. During a full synodic period, properties of the local magnetospheric field and thermal plasma environment change by an order of magnitude, and Callisto’s resulting interaction with the ambient plasma displays a strong variability. In this study, we combine results from the AIKEF hybrid and GENTOo test-particle models to constrain the variability of energetic particle dynamics and quantify their flux onto the top of Callisto’s atmosphere during a synodic period. For three positions of Callisto with respect to the center of the Jovian current sheet (at maximum distance above, maximum distance below, and embedded within), we model the interaction between Callisto’s atmosphere/ionosphere, its induced field, and ambient magnetospheric plasma environment, and we trace energetic ions (hydrogen, oxygen, and sulfur) and electrons through the perturbed electromagnetic fields. Our findings highlight the important role that Callisto's interaction with the low energy magnetospheric plasma and signatures associated with the moon’s induced field have on shaping the dynamics and flux patterns of the high-energy particles, which may play a role in the asymmetric ionization of, and energy deposition into, Callisto's neutral atmosphere.

To present the observation of multifocal evanescent white dot syndrome (MEWDS)-like phenotypes developing in association with the onset of choroidal neovascularization (CNV) in a series of patients.Patients presenting to tertiary-care centers with MEWDS-like phenotypes and CNV were identified.Five patients presented for the management of CNV in the context of previous diagnoses of punctate inner choroidopathy (PIC) and/or myopia. In time-periods ranging from 0 days to 12 weeks from the diagnosis of active CNV, MEWDS-like changes were observed. Treatment with anti-VEGF agents were instituted in four cases, in an as-required protocol. 1 patient received systemic steroid.The development of MEWDS-like phenotypes in association with CNVM can occur in eyes with either inflammatory or non-inflammatory CNVM, and in those who were or were not treated with anti-VEGF therapy. The association suggests an inflammatory event, which causes RPE changes and probably induces the development of the CNV.

For the entire ion energy range observed at Europa, we calculate spatially resolved maps of the surface sputtering rates of H2O, O2, and H2 from impacts by magnetospheric ions. We use the perturbed electromagnetic fields from a hybrid model of Europa’s plasma interaction, along with a particle-tracing tool, to calculate the trajectories of magnetospheric ions impinging onto the surface and their resultant sputtering yields. We examine how the distribution of the sputtering rates depends on the electromagnetic field perturbations, the angle between the solar radiation and the corotating plasma flow, and the thickness of the oxygen-bearing layer within Europa’s surface. Our major findings are: (a) Magnetic field-line draping partially diverts the impinging ions around Europa, reducing the sputtering rates on the upstream hemisphere, but allowing for substantial sputtering from the downstream hemisphere. In contrast, zero sputtering occurs in much of the downstream hemisphere with uniform electromagnetic fields. (b) If the oxygen-bearing surface layer is thin compared to the penetration depth of magnetospheric ions, thermal ions dominate the O2 sputtering rates, and the region of strongest sputtering is persistently located near the upstream apex. However, if the oxygen-bearing layer is thick compared to the penetration depth, energetic ions sputter the most O2, and the location of maximum sputtering follows the sub-solar point as Europa orbits Jupiter. (c) The global production rate of O2 from Europa’s surface varies by a factor of 3 depending upon the moon’s orbital position, with the maximum particle release occurring when Europa’s Sun-lit and upstream hemispheres coincide.

For the entire ion energy range observed at Europa, we calculate spatially-resolved maps of the surface sputtering rates of H2O, O2, and H2 from impacts by magnetospheric ions. We use the perturbed electromagnetic fields from a hybrid model of Europa’s plasma interaction, along with a particle-tracing tool, to calculate the trajectories of magnetospheric ions impinging onto the surface and their resultant sputtering yields. We examine how the distribution of the sputtering rates depends on the electromagnetic field perturbations, the angle between the solar radiation and the corotating plasma flow, and the thickness of the oxygen-bearing layer within Europa's surface. Our major findings are: (a) Magnetic field-line draping partially diverts the impinging ions around Europa, reducing the sputtering rates on the upstream hemisphere, but allowing for substantial sputtering from the downstream hemisphere. In contrast, zero sputtering occurs in much of the downstream hemisphere with uniform electromagnetic fields. (b) If the oxygen-bearing surface layer is thin compared to the penetration depth of magnetospheric ions, thermal ions dominate the O2 sputtering rates, and the region of strongest sputtering is persistently located near the upstream apex. However, if the oxygen-bearing layer is thick compared to the penetration depth, energetic ions sputter the most O2, and the location of maximum sputtering follows the sub-solar point as Europa orbits Jupiter. (c) The global production rate of O2 from Europa’s surface varies by a factor of three depending upon the moon's orbital position, with the maximum particle release occurring when Europa's sun-lit and upstream hemispheres coincide.

Purpose: To report a case of exuberant anterior chamber inflammation post partial removal of supramid® stent.Methods: Case report.Results: The sudden intraocular pressure drop induced by partial removal of ripcord suture from a glaucoma drainage device can result in blood-retinal and blood-aqueous barrier breakdown, inducing uveitis.Conclusions: Intensive inflammatory prophylaxis prior to maneuvers to reduce intraocular pressure may reduce the risk of severe intraocular inflammation in patients with a previous history of uveitis as a consequence of sudden hypotony.

Introduction To report the 52-week treatment outcomes with intravitreal injections of aflibercept using a treat-and-extend regimen for treating macular edema secondary to central retinal vein occlusion (CRVO). Methods A retrospective analysis of patients newly diagnosed with CRVO was performed. Patients receiving aflibercept between 1 December 2016 and 31 March 2017 were included in the analysis. Data on age, gender, visual acuity measured on Early Treatment of Diabetic Retinopathy Study charts, presence of macular and peripheral ischemia, anatomical changes observed on spectral domain–optical coherence tomography examination and the number of injections needed were recorded. Results The mean gain in vision was 17.8 ± 19.1 (± standard deviation) letters and 15.1 ± 20.2 letters at weeks 24 and 52 of follow-up, respectively. The proportion of patients who gained ≥ 15 letters in best-corrected visual acuity was 52.9% at week 24 and 50% at week 52. The mean reduction in central subfield macular thickness was 331.5 and 311.6 at weeks 24 and week 52, respectively. For the patients completing 52 weeks of follow-up, the mean number of treatments was 4.9 ± 1.3 injections in the first 26 weeks and 3.2 ± 2.0 injections in the second 26 weeks. Conclusions The Moorfields protocol for treating macula edema in CRVO achieves a quick response to treatment without over- or under-treating patients with a fixed protocol. Overall, our individualized treat-and-extend protocol achieved real-life outcomes approaching those of clinical trials. As there are currently no such trials using this practically useful regimen, our study provides real-world evidence for using a treat-and-extend protocol for aflibercept in CRVO.

We model energetic and thermal ion dynamics in the perturbed electromagnetic fields at Jupiter’s moon Europa. At the location of its orbit, Europa experiences a periodic variation in background electromagnetic field strength and orientation as well as plasma conditions while Jupiter completes a synodic rotation. We use a hybrid simulation (kinetic ions, fluid electrons) to model field perturbations due to the interaction of the corotating plasma with the ionosphere and induced dipole moment under these varying background conditions. For three cases, (I) Europa at the center of the plasma sheet, (II) Europa at its maximum distance north of the plasma sheet, and (III) Europa at its maximum distance south of the plasma sheet, we calculate surface precipitation maps of energetic magnetospheric ions using a backtracing tool. The effects of the time-varying field perturbations on surface precipitation have not previously been modeled. For three of the dominant ion species (H+, O2+, and S3+), we model the spatial distribution of surface flux over the full range of ion energies observed by the Galileo spacecraft (100 eV to about 10MeV). Our results show that the field perturbations drastically affect surface fluxes. While polar regions receive consistently high particle flux, low-latitude and equatorial regions are partially shielded by draped magnetic field lines close to the moon. These shielded regions migrate in longitude and latitude across Europa’s surface as Jupiter progresses through a full synodic rotation.

Objective: To analyze the factors affecting the treatment outcome in patients with presumed ocular tuberculosis on anti-tubercular therapy (ATT).Methods: Retrospective chart review of patients with presumed ocular tuberculosis seen at a tertiary referral eye care center in the United Kingdom. Failure was defined as recurrence of inflammation within 6 months of completion of ATT.Results: There were a total of 175 patients with presumed ocular tuberculosis who had ATT. Patients with intermediate uveitis or panuveitis and those on immunosuppressive therapy had higher odds of treatment failure (p

Background To evaluate the contribution made to the diagnostic work-up for patients with suspected ocular tuberculosis (TB) by QuantiFERON-TB Gold In-Tube (QFT) tests using latent class analysis model. Methods A single centre retrospective cohort study. A Bayesian latent class model was constructed on the basis of demographics, phenotypes and test results from patients attending a tertiary referral center in the UK. This estimated the probability of ocular TB for each patient in two versions, first with and then without QFT. The estimated probability of ocular TB was compared with treatment failure. Results From a database of 365 patients with clinical signs suggestive of ocular TB, 267 patients who had QFT and complete data were evaluated. Mean age was 45.0 ± 15.4 years with 141 (52.9%) male and 148 (50.5%) of Asian ethnicity. QFT was positive in 208 (70.1%) patients and ATT was instituted in 145 (49.5%) patients with 100 (34.1%) patients also having concurrent systemic corticosteroid therapy. The best estimate of a QFT level separating TB-positive and TB-negative patients was extremely low. This weak discrimination between TB and non-TB groups was reflected in poor positive and negative predictive values for treatment failure. Conclusions The latent class model did not successfully predict treatment failure, despite taking all variables into account. The threshold between TB and non-TB in QFT values was implausibly low and removing QFT from the model made prediction slightly worse. A larger prospective study is required to establish the role of all tests, demographics and phenotypes in diagnosis. Electronic supplementary material The online version of this article (10.1186/s12886-017-0597-x) contains supplementary material, which is available to authorized users.

Purpose Describe the clinical features and outcomes of patients with peripheral retinal vasculitis (RV) and describe clinical characteristics of presumed tubercular RV in a nonendemic setting. Methods Retrospective cohort study of 110 consecutive patients with peripheral RV at a tertiary referral eye care center in the United Kingdom. Retinal vasculitis was defined as RV with vitritis associated with peripheral retinal ischemia. Patients who also had positive Quantiferon Gold in Tube test, positive tuberculin skin test, and/or other evidence of systemic tuberculosis such as biopsy were labeled with presumed tubercular RV. Treatment success was defined as resolution of inflammation, and successful tapering of oral corticosteroids to less than 10 mg/day or topical steroids to less than twice a day. Results Mean age of the study population was 42.69 ± 14.95 years. Patients were predominantly Asian (49.1%) and Male (67.0%). A total of 73.2% had bilateral involvement. Sixty-nine (62.72%) patients had presumed tubercular RV. A total of 52.8% patients received antitubercular therapy, 65.5% received oral corticosteroids, and 17.3% required steroid-sparing oral immunosuppressive agents. A total of 85.19% of patients with presumed tubercular RV achieved treatment success with concurrent antitubercular therapy as against 75.61% of patients with nontubercular RV. Conclusion This is the largest study of the epidemiology, clinical features, and outcomes of both peripheral RV and presumed tubercular RV to date. Presumed tubercular RV commonly seems to affect young males of Asian descent and had vitreous hemorrhage as common clinical findings and also demonstrated a good treatment outcome with antitubercular therapy.

To evaluate rates of vitreous relapse among retinoblastoma patients treated with primary chemotherapy and assess diode laser as a potential risk factor for relapse.Retrospective review of all patients treated with primary chemotherapy at a large ocular oncology centre. Eyes that developed vitreous relapse were coded with regard to Reese-Ellsworth Group, laterality, time to relapse, type of relapse (vitreous base or non-vitreous base relapse), treatments used (including adjuvant diode laser), and ocular preservation. Individual tumour foci treated with laser hyperthermia were also coded for laser parameters including power settings, number of treatments, and concomitant administration of systemic chemotherapy (chemothermotherapy).15 of 106 eyes (14.15%) developed vitreous relapse over a 6 year period. Mean time to relapse was 7.2 months after chemotherapy was completed. Five cases (33%) were of the vitreous base variety. Ocular salvage was attempted in 11 cases using a variety of methods; one patient was lost to follow up. Six of the remaining 10 eyes (60%) were salvaged. Eight of 38 eyes (21%) treated with systemic chemotherapy and laser hyperthermia developed vitreous relapse compared with seven of 68 eyes (10%) treated with primary chemotherapy alone (p0.005). Laser settings, number of hyperthermia treatments, and the concomitant use of systemic chemotherapy (chemothermotherapy) were not associated with higher rates of vitreous relapse.Nearly one in seven eyes with retinoblastoma treated with primary chemotherapy may develop vitreous relapse. The administration of diode laser hyperthermia appears to increase this risk. Despite additional therapy a number of these eyes succumb to enucleation.

Aim: To report a case of optic neuropathy secondary to Linezolid, second line anti tuberculosis agent. Case Report: 22 year Indian male with multidrug resistant spinal tuberculosis and TB meningitis was started on second line anti tuberculosis drugs. Within one month of onset of second line anti TB drug, he was noted to have optic neuropathy in both eyes. Visual field and electro diagnostics suggested optic neuropathy. Discussion: Linezolid is a synthetic oxazolidinone broad spectrum antibiotic and has been in off label use for multidrug resistant tuberculosis (MDR-TB). There are very scattered case reports of optic neuropathy secondary to use of this off label drug. In our case, the optic neuropathy was however reversible on stoppage of the drug. Conclusion: It seems prudent that baseline ophthalmological evaluation to be done for all patients to be subjected for treatment with this drug for any short term or long term therapy.

AIM: To assess the impact of antitubercular therapy (ATT), oral steroids and steroid sparing immunosuppressive treatment on treatment success in cases with presumed ocular tuberculosis in an area of low endemic prevalence. METHODS: A retrospective cross-sectional study was performed for 213 patients with presumed ocular tuberculosis from a database from a tertiary referral eye hospital in the UK. A logistic regression model was constructed incorporating demographics, baseline characteristics and different cut-offs of QuantiFERON-TB Gold In-Tube test (QFT-G) to identify significant factors accounting for the variability of the response variable ('failure') across the whole group. Treatment failure was defined as the recurrence of inflammation or inability to taper steroids within 6 months of completion of ATT or after at least 6 months of treatment in the non-ATT group. RESULTS: There were 126 patients who had at least 6 months of ATT. Patients with QFT-G values >1.50 (OR=0.20, 95% CI 0.09 to 0.48, p1.5) are more likely to have treatment success with ATT. In our model, steroid sparing immunosuppressive agents reduced the chances of success in both ATT and non-ATT-treated patients. It is unclear whether this effect reflects the intrinsic underlying severity of disease (ie, study bias), or whether steroid sparing immunosuppressive agents mitigate against successful ATT.

Background Post-kala-azar dermal leishmaniasis is a well-known immunologic cutaneous reaction. There are few case reports of ocular leishmaniasis. It is a sight-threatening condition that needs to be rapidly recognized and treated to avoid permanent visual loss. Ocular leishmaniasis panuveitis can present with severe inflammation in patients with highly active anti-retroviral therapy (HAART)-induced immune reconstitution syndrome. Findings A case of a 40-year-old man, human immunodeficiency virus (HIV) positive on HAART, with a presumed diagnosis of ocular leishmaniasis, is presented. He had a past history of visceral leishmaniasis and was referred to the uveitis service with rapidly worsening panuveitis and counting fingers vision in both eyes. On empirical anti-leishmania therapy and systemic steroids, the visual acuity of the left eye improved to 6/9 but remained poor in the right eye. Based on the medical history, improvement with therapy and the exclusion of other common infections, a presumed diagnosis of ocular leishmaniasis-related panuveitis was made. Conclusions A major immune reaction against lingering parasites may play a key role in the pathogenesis of this sight-threatening and rapidly progressive condition. Both the infection and the immune reaction should be treated.

Purpose To report two cases of desegmentation or fracture of the Ozurdex implant observed immediately after routine intravitreal implantation for macular oedema. Patients In two patients receiving intravitreal Ozurdex implant injection, a rare complication of fracture of implant was noted immediately after the injection. No additional complication was noted in either of the patients. On follow-up, the macular oedema had resolved and there were no further complications. Discussion We shared our experience with the manufacturer, and it was confirmed that, during the normal degradation process, the implant may become soft and break into pieces. Allergan shared their unpublished data on in vivo and in vitro drug release profile of one piece versus three pieces of implant, which is presented in this case report. Conclusions With more and more microsurgical implantation procedures, clinicians should be well aware of these unusual although rare complications. Even though the desegmented implants do not appear to cause more intraocular complications compared with single-piece implants, patients with defragmented implants should be followed up carefully to monitor for unexpected complications.

Purpose To evaluate the clinical utility of optical coherence tomography angiography (OCTA) in patients with retinal vein occlusion (RVO), and to systematically compare OCTA images with changes seen on color fundus photography and fluorescein angiography (FA). Design Reliability analysis. Methods Eighty-one eyes of 76 patients with a history of RVO (branch, central, or hemicentral), both acute and chronic, underwent OCTA and color fundus photography. In 29 eyes, data were compared to FA imaging. Comparative and multimodal analysis of the 3 imaging procedures were performed. Results We identified good agreement between FA and OCTA scans centered on the macula for capillary nonperfusion (intraclass correlation coefficient [ICC] 0.825 for the 3 × 3-mm scan and 0.891 for the 8 × 8-mm scan). Agreement for area of capillary changes (dilation, pruning, and telangiectasia) was also substantial (ICC 0.712 for the 3 × 3-mm scan and 0.787 for the 8 × 8-mm scan). For foveal avascular zone grading, agreement was good for the 3 × 3-mm scan (kappa = 1.000 for radius and kappa = 0.799 for outline) but poor for the 8 × 8-mm scan (kappa = 0.156 for radius and kappa = 0.600 for outline). The quality of the images obtained was an important issue for OCTA, as 15.1% of scans were nongradable, particularly in patients unable to maintain fixation. Conclusions OCTA is a quick, reliable, and noninvasive method to evaluate the area of capillary nonperfusion and foveal avascular zone morphology in patients with RVO. However, good fixation is a requirement for acquisition of good-quality images.

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Purpose: To screen for mutations of connexin50 (Cx50)/GJA8 in a panel of patients with inherited cataract and to determine the cellular and functional consequences of the identified mutation. Methods: All patients in the study underwent a full clinical examination and leukocyte DNA was extracted from venous blood. The GJA8 gene was sequenced directly. Connexin function and cellular trafficking were examined by expression in Xenopus oocytes and HeLa cells. Results: Screening of the GJA8 gene identified a 139 G to A transition that resulted in the replacement of aspartic acid by asparagine (D47N) in the coding region of Cx50. This change co-segregated with cataract among affected members of a family with autosomal dominant nuclear pulverulent. While pairs of Xenopus oocytes injected with wild type Cx50 RNA formed functional gap junction channels, pairs of oocytes injected with Cx50D47N showed no detectable intercellular conductance. Co-expression of Cx50D47N did not inhibit gap junctional conductance of wild type Cx50. In transiently transfected HeLa cells, wild type Cx50 localized to appositional membranes and within the perinuclear region, but Cx50D47N showed no immunostaining at appositional membranes with immunoreactivity confined to the cytoplasm. Incubation of HeLa cells transfected with Cx50D47N at 27oC resulted in formation of gap junctional plaques. Conclusions: The pulverulent cataracts present in members of this family are associated with a novel GJA8 mutation, Cx50D47N, that acts as a loss-of-function mutation. The consequent decrease in lens intercellular communication and biochemical changes associated with the intracellular retention of the mutant connexin may contribute to cataract formation.

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Background Acute maculopathy is a rare condition of unknown aetiology and Coxsackie virus is known to be associated with this macular chorioretinitis. Findings We report a case of acute unilateral maculopathy in a 35-year-old woman with concurrent hand foot and mouth disease. Furthermore, we display multimodal imaging (colour fundus photographs, autofluorescence, spectral domain ocular coherence tomography, fluorescein angiography and indocyanine green angiography) charting the course of the disease. The source of the virus was thought to be the patient's child. Empirical treatment with oral corticosteroids was commenced and the inflammation resolved, leaving a residual macular scar. Conclusions We present this case combined with the review of literature of adult onset Coxsackie-virus-associated retinitis. This case reiterates the fact that Coxsackie virus is an uncommon but important consideration in the differential diagnosis of chorioretinitis and posterior uveitis with atypical retinopathy.