Management of anterior chamber dislocation of a dexamethasone intravitreal implant: a case report

Background Ozurdex is a 700 mcg dexamethasone intravitreal implant, approved for the management of macular edema secondary to retinal vein occlusion, and other related pathoglogiesAnterior chamber dislocation of Ozurdex represents an uncommon complication of the intravitreal injection, which can be managed by repositioning the implant into the vitreous cavity. We describe the case of a successful repositioning of an Ozurdex implant by mobilization and subsequent balanced saline solution injection in the anterior chamber. Case presentation An 83-year-old white woman presented to our Emergency Unit complaining of pain and vision loss in herright eye lasting a week. Her anamnesis revealed a history of persistent cystoid macular edema after phacoemulsification with scleral-fixated posterior chamber intraocular lens implantation, recently treated with an intravitreal Ozurdex implant. She also took a long-distance flight 2 days after the injection. An anterior segment examination showed corneal edema and the rod implant adherent to corneal endothelium. To avoid corneal decompensation, we opted for a implant repositioning. Under topical anesthesia, a 30-gauge needle was introduced through a limbar incisionto mobilize the dislocated rod. Balanced saline solution was injected, with a successful repositioning of the implant into the vitreous cavity. Topical 5 % hypertonic saline solution and 0.2 % betamethasone associated with 0.5 % chloramphenicol drops were administered four times a day. To prevent redislocation of the Ozurdex implant, she was instructed to avoid prone position, any kind of physical effort, and not to undertake long-distance flights during the first postoperative week. One week after surgery, an anterior segment examination showed an improvement of corneal edema. Funduscopy showed that the Ozurdex implant was settled into the vitreous cavity. Conclusions Anterior chamber dislocation of Ozurdex from the vitreous cavity is rare. In our patient, in addition to the posterior capsule tearing, the long-distance flight could have contributed to implant dislocation. Repositioning of the implant is necessary to avoid endothelial decompensation. It can be carried out by using saline balanced solution with the same efficacy as other surgical procedures reported in the literature. A possible disadvantage of this procedure could be implant migration

Changes in mucosa laryngopharyngeal vascularization after radiotherapy and concomitant chemotherapy observed with narrow band imaging. Description of two cases

Introducción y objetivo: La imagen de banda estrecha o Narrow Band Imaging (NBI) es un sistema de mejora de imagen utilizado en la detección de anomalías vasculares en la mucosa y submucosa con neoplasia. En 2011 Ni estableció los cinco tipos de patrones de imágenes en la mucosa laríngea relacionándolos con los hallazgos histopatológicos de las lesiones. Sin embargo, estos patrones se ven modificados por tratamientos previos de cirugía láser, radioterapia y quimioterapia. Nuestro objetivo es describir las imágenes tipo con NBI obtenidas en pacientes tratados con el esquema terapéutico de radioterapia y quimioterapia concomitante. Descripción: Imágenes de NBI en paciente de 68 años con carcinoma epidermoide no queratinizante supraglótico estadio III tratado con radioterapia y quimioterapia concomitante a los tres meses y al año posterior al tratamiento. Imágenes de NBI en paciente de 50 años con carcinoma epidermoide no queratinizante de nasofaringe estadio II tratado con radioterapia y quimioterapia concomitante a los tres meses y al año posterior al tratamiento. Resultados: Los patrones obtenidos no se identifican con ninguno de los establecidos previamente por Ni. Las imágenes difieren en función del tiempo transcurrido desde el tratamiento. Conclusiones: Es importante conocer las alteraciones observadas en la mucosa y submucosa de pacientes tratados con radioterapia y quimioterapia concomitante ya que difieren de los patrones característicos descritos por Ni asociados a la presencia de neoplasia.Introduction and objective: Narrow Band Imaging (NBI) is an image enhancement system used to detect vascular anomalies in the mucosa and submucosa of neoplasms. In 2011 Ni established the five types of imaging patterns in the laryngeal mucosa relating them to the histopathological findings of the lesions. However, these patterns are modified by previous treatments of laser surgery, radiotherapy and chemotherapy. Our objective is to describe the NBI type images obtained in patients treated with the therapeutic regimen of radiotherapy and concomitant chemotherapy. Description: NBI images in a 68-yearold patient with stage III supraglottic non-keratinizing squamous cell carcinoma treated with radiotherapy and concomitant chemotherapy at three months and the year after treatment. NBI images in a 50-year-old patient with stage II nasopharynx non-keratinizing squamous cell carcinoma treated with radiotherapy and concomitant chemotherapy at three months and the year after treatment. Results: The obtained patterns are not identified with any of those previously established by Ni. The images differ depending on the time elapsed since the treatment. Conclusions: It is important to know the alterations observed in the mucosa and submucosa of patients treated with radiotherapy and concomitant chemotherapy since they differ from the characteristic patterns described by Ni associated with the presence of neoplasia

Bipartite Interference and Air Pollution Transport: Estimating Health Effects of Power Plant Interventions

Evaluating air quality interventions is confronted with the challenge of interference since interventions at a particular pollution source likely impact air quality and health at distant locations and air quality and health at any given location are likely impacted by interventions at many sources. The structure of interference in this context is dictated by complex atmospheric processes governing how pollution emitted from a particular source is transformed and transported across space, and can be cast with a bipartite structure reflecting the two distinct types of units: 1) interventional units on which treatments are applied or withheld to change pollution emissions; and 2) outcome units on which outcomes of primary interest are measured. We propose new estimands for bipartite causal inference with interference that construe two components of treatment: a "key-associated" (or "individual") treatment and an "upwind" (or "neighborhood") treatment. Estimation is carried out using a semi-parametric adjustment approach based on joint propensity scores. A reduced-complexity atmospheric model is deployed to characterize the structure of the interference network by modeling the movement of air parcels through time and space. The new methods are deployed to evaluate the effectiveness of installing flue-gas desulfurization scrubbers on 472 coal-burning power plants (the interventional units) in reducing Medicare hospitalizations among 22,603,597 Medicare beneficiaries residing across 23,675 ZIP codes in the United States (the outcome units)

Strong current response to slow modulation: a metabolic case-study

We study the current response to periodic driving of a crucial biochemical reaction network, namely, substrate inhibition. We focus on the conversion rate of substrate into product under time-varying metabolic conditions, modeled by a periodic modulation of the product concentration. We find that the system exhibits a strong nonlinear response to small driving frequencies both for the mean time-averaged current and for the fluctuations. For the first, we obtain an analytic formula by coarse-graining the original model to a solvable one. The result is nonperturbative in the modulation amplitude and frequency. We then refine the picture by studying the stochastic dynamics of the full system using a large deviations approach, that allows to show the resonant effect at the level of the time-averaged variance and signal-to-noise ratio. Finally, we discuss how this nonequilibrium effect may play a role in metabolic and synthetic networks.Comment: 10 pages, 7 figures Updated fig.5 and appendix with geometric effect

Mainstreaming prevention: Prescribing fruit and vegetables as a brief intervention in primary care

This is the author's PDF version of an article published in Public health© 2005.This articles discusses a project at the Castlefields Health Centre in Halton whereby primary care professionals issue a prescription for discounts on fruit and vegetables. The prescription is explicitly linked to the five-a-day message