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Background/objectives: To compare the number of eye surgical procedures performed in Italy in the 2 months following the beginning of lockdown (study period) because of COVID-19 epidemic with those performed in the two earlier months of the same year (intra-year control) and in the period of 2019 corresponding to the lockdown (inter-year control). Methods: Retrospective analysis of surgical procedures carried out at 39 Academic hospitals. A distinction was made between elective and urgent procedures. Intravitreal injections were also considered. Percentages for all surgical procedures and incidence rate ratios (IRR) for rhegmatogenous retinal detachment (RRD) events were calculated. A p value <0.05 was considered significant. Results: A total of 20,886 versus 55,259 and 56,640 patients underwent surgery during the lockdown versus intra-and inter-year control periods, respectively. During the lockdown, only 70% of patients for whom an operation/intravitreal injection was recommended, finally underwent surgery; the remaining patients did not attend because afraid of getting infected at the hospital (23%), taking public transportation (6.5%), or unavailable swabs (0.5%). Elective surgeries were reduced by 96.2% and 96.4%, urgent surgeries by 49.7% and 50.2%, and intravitreal injections by 48.5% and 48.6% in the lockdown period in comparison to intra-year and inter-year control periods, respectively. IRRs for RRDs during lockdown dropped significantly in comparison with intra- and inter-year control periods (CI: 0.65–0.80 and 0.61–0.75, respectively, p < 0.001 for both). Conclusion: This study provides a quantitative analysis of the reduction of eye surgical procedures performed in Italy because of the COVID-19 epidemic.

Objective: Three-dimensional (3D), high-definition (HD) endoscopy has been recently introduced in neurosurgery, and its value has been discussed extensively in endonasal skull base surgery. Because there has been no reported clinical series on the use of a recent 3D-HD ventriculoscope, the aim of this study was to describe our initial experience with this novel device. Methods: Patients consecutively operated on from June 2016 to June 2018 with a 3D-HD ventriculoscope were prospectively collected. The system is a 6-mm, 0-degree optic with a 105-degree field of view, with a central working channel of 2.2-mm diameter and 2 side channels of 1.3-mm diameter. Patients' demographic data, preoperative symptoms, and neurologic status; neuroradiologic data; type of surgery; operative time; intraoperative and postoperative complications, and follow-up data were prospectively recorded and retrospectively reviewed. Results: Twenty-four patients (age range: 3−84 years) underwent 25 procedures including endoscopic third ventriculocisternostomy, biopsy, and cyst fenestration. The technical goal of surgery was obtained in all patients. There were no intraoperative complications, expect for 1 intraoperative epileptic seizure. Postoperative complications included asymptomatic subdural collections in 2 patients, infection, and delayed endoscopic third ventriculocisternostomy closure in 1 patient each. Relative limits of the system are its size and the availability of only a 0-degree optic. Image quality appeared satisfactory in all procedures. The lack of a dedicated introducer was resolved, exploiting a vascular “peel-away” system. Conclusions: 3D-HD technology seems to provide potential advantages in ventricular surgery. This initial experience is promising but must be confirmed by larger series.

Background: A variety of antiinflammatory therapies are employed to promote corneal wound healing. The effects of steroidal and nonsteroidal antiinflammatory drugs on the biomechanical properties of rabbit cornea were investigated over time using tensile tests. Methods: Full-thickness incisions were made and used to analyze the effects of dexamethasone sodium phosphate 0.1% and diclofenac sodium 0.1% on corneal biomechanical properties during wound healing at 7, 14 and 21 days after surgery. Results: The full-thickness incision deeply modified all of the mechanical properties. At 3 weeks after incision, regardless of the drug therapy, the tensile modulus was about 70% of the value for the intact cornea. Conclusions: Topical treatment with dexamethasone was particularly effective during the first week after surgery; the second week after surgery, a similar result was observed in the corneas treated with diclofenac. Low doses of steroidal and nonsteroidal antiinflammatory drugs would seem to have the potential to improve biomechanical properties only during the early stage of the healing process of the cornea.

A 41-year-old caucasian male was referred to the Glaucoma clinic at our tertiary referral centre with a diagnosis of normal tension glaucoma after the finding of increased bilateral asymmetrical cup/disc ratios, with normal intraocular pressures. On examination, the authors confirmed the presence of bilateral reduced optic disc rims alongside a left pale residual rim, and a further discovered a positive dyschromatopsia with a bilateral visual field alteration. The left visual field showed a relative scotoma confined to the vertical midline. After initiating investigation for suspected glaucoma, the authors ordered a magnetic resonance imaging that evidenced an internal carotid aneurysm along the ophthalmic segment, stretching across the optic chiasm with a major involvement of the left optic nerve and partial involvement of the right optic nerve. Aneurysm embolisation was performed with complete resolution of signs and symptoms achieved 5 months post-operatively. Despite glaucoma being the most frequent condition causing optic disc atrophy and visual field loss, it is not the only cause. Any atypical visual field defect not in keeping with a glaucomatous field loss should be further investigated. The ophthalmologist should thoroughly assess all signs that could lead to different diagnosis.

Most studies employing experimental models of unilateral glaucoma have used the normotensive contralateral eye as the normal control. However, some studies have recently reported the activation of the retinal macroglia and microglia in the uninjured eye, suggesting that the eye contralateral to experimental glaucoma should not be used as a control. This review analyzes the studies describing the contralateral findings and discusses some of the routes through which the signals can reach the contralateral eye to initiate the glial reactivation.

Most studies employing experimental models of unilateral glaucoma have used the normotensive contralateral eye as the normal control. However, some studies have recently reported the activation of the retinal macroglia and microglia in the uninjured eye, suggesting that the eye contralateral to experimental glaucoma should not be used as a control. This review analyzes the studies describing the contralateral findings and discusses some of the routes through which the signals can reach the contralateral eye to initiate the glial reactivation.

Exfoliation or pseudoexfoliation syndrome (PXF) is an age-related ocular and systemic disease in which abnormal extracellular material is produced and accumulates in many tissues. PXF is the most common identifiable cause of open-angle glaucoma (OAG). PXFG is a particularly aggressive type of OAG, which runs with a faster rate of progression and poorer response to medical therapy than primary OAG (POAG). The prevalence of the condition shows huge variations among different population, Scandinavian and Mediterranean race being the most affected. Many genetics and environmental factors are involved in the pathogenesis and remarkable progresses in understanding the involved factors have been achieved in the past years. Population-based studies have identified mutations on the lysil-oxidase-like 1(LOXL1) gene as a risk factor for PXFS. Environmental and behavioral factors such as latitude of residence, caffeine intake, and vitamins deficiency are under investigation for a possible involvement in determining the disease in genetically predisposed individuals. Treatment options are similar to those recommended for POAG. Exfoliation syndrome predisposes to capsular rupture, zonular dehiscence, and vitreous loss during cataract extraction. Laser trabeculoplasty has been demonstrated to show good clinical outcomes in PXF patients. A review of the current literature and scientific evidences on pathogenesis and treatment is presented.

The interconnection of distributed generators in low voltage (LV) networks, together with storage systems, could cause a substantial change in grid operational practice: currently a rising idea proposes to treat generators, storage systems and even loads as distributed energy resources (DER), able to supply services to the grid and accept on-line requests. To emphasise the advantages of Distributed Generation (DG) it is necessary to face the problem with a system approach. In this work both type of services, namely those provided by each generator and those deriving from the co-ordination of different resources, have been investigated. The option represented by a complex master-slave configuration has been discarded in order to avoid its fast communication and control requirements. Instead a prototype based on a centralised resource management solution and a somewhat plug-and-play functionality for each generator has been developed. For this purpose, different control systems have been implemented in order to act during fast transient dynamics due to random load or configuration changes, or to manage the slow modifications of the system conditions due to daily, weekly and seasonal load variations. The regulators of every distributed resource are requested to give response to fast and unpredictable transient dynamics, i.e. to participate to voltage and frequency regulations, harmonic compensations and phase balancing, while a central dispatcher has been conceived as to periodically update the regulators set-points in order to exploit the capabilities of each distributed resource either for present and foreseen grid operating conditions. For voltage and frequency regulations, a specific droop control algorithm has been designed so to be implemented on board of generators connected to the LV grid by an inverter device. In the conceived scenario, each machine, working in parallel with the others, takes on part of the regulation according to its capabilities. For the opt

Vertical electric field waveforms of leader-return stroke sequences measured 500 m and 30 m from rocket-triggered lightning are presented. The 500-m data were recorded during the summer of 1986, the 30-m data during the summer of 1991, both at the NASA Kennedy Space Center, Florida. The 40 leader-return stroke field waveforms at 500 m and the 8 waveforms at 30 m all appear as asymmetrical V-shaped pulses, the bottom of the V being associated with the transition from the leader to the return stroke. Only two waveforms at 30 m were suitable for quantitative analysis. The widths of the V at half of peak value for these are 1.8 and 5.0 Όs, while for the 500-m data they are 1 to 2 orders of magnitude greater, with a median value of 100 Όs. Applying a widely used and simple leader model to the measured leader electric fields at 500 m, we infer, for the bottom kilometer or so of the leader channel, leader speeds between 2×106 and 2×107 m/s and leader charges per unit length of 0.02×10−3 to 0.08×10−3 C/m. From the two measured leader electric field changes at 30 m we infer, using the same leader model, for the bottom 100 meters or so of the leader channel, speeds of 3×107 and 1×107 m/s (the corresponding measured waveform half widths are 1.8 Όs and 5.0 Όs) and charges per unit length of 0.14×10−3 and 0.02×10−3 C/m (the corresponding measured leader field changes are 81 kV/m and 12 kV/m). The corresponding measured return stroke peak currents for the above two cases are 40 kA and 7 kA, respectively. A positive correlation is observed between the magnitude of the leader field change at 500 m and the ensuing return stroke current peak.