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Outcomes of intravitreal dexamethasone implant (Ozurdex®) in patients with post-surgical macular edema – a real-world scenario
(2025-01-10) de Oliveira Júnior, Elder O.; Ahn, Isabel; Fernandes, Rodrigo A. B.; Fernandes, Arthur G.
Abstract Background Clinically significant macular edema (CME) is the leading cause of visual loss after ophthalmologic surgery due to the release of inflammatory mediators promoted by the procedures. We aimed to evaluate the outcomes of intravitreal Ozurdex® (700 µg dexamethasone) implants as a primary therapeutical option for post-surgical macular edema cases. Methods Patients with post-surgical macular edema diagnosed by optical coherence tomography (Cirrus SD-OCT) and treated with Ozudex were selected for the current study. Data was retrospectively collected from medical records from January 2020 to December 2022 and included sex, age, laterality, and timeline of treatment (i.e. implant alone or at the time of silicon oil removal in cases requiring vitreorretinal surgery). Complications associated with treatment were also noted as well as the need of further treatments. The structural analysis focused on measuring central macular thickness (CMT—average thickness within the 1 mm circle of the ETDRS) from the internal limiting membrane to the Bruch’s membrane complex, as well as the average total macular thickness including parafoveal and perifoveal regions determined by the device (CAT). The functional evaluation was based on the best-corrected visual acuity (VA) measured in logMAR. Results A total of 46 participants were included (56.2% males, mean age: 60.9 ± 11.2 years old). A statistically significant change was observed in the postoperative versus the preoperative period for all parameters (p < 0.05). The mean VA difference was − 0.17 ± 0.24; CMT was − 109.22 ± 124.85 and CAT was − 14.76 ± 58.95. We observed a significant effect of the moment of Ozurdex implantation on VA improvement, so that cases with implantation at the time of oil removal showed lower improvement than cases with implantation at a distinct timing (Coef. 0.19, 95%CI: 0.02 to 0.36, p = 0.027). Eleven cases (23.9%) required further treatment such as new Ozurdex implantation (8 cases) or surgery (3 cases). Only one case (2.17%) showed increased intraocular pressure and underwent glaucoma surgery. Conclusions Intravitreal Ozurdex implants significantly improved functional and structural aspects in post-surgical macular edema. The timing of implantation influenced VA improvement, with a distinct step approach showing better outcomes than at the time of oil removal.
Aggressive Subtypes of Laryngeal Chondrosarcoma and their Clinical Behavior: A Systematic Review
(2025-01-05) Piazza, Cesare; Montenegro, Claudia; Tomasoni, Michele; Leivo, Ilmo; Stenman, Göran; Agaimy, Abbas; Simpson, Roderick H. W.; Zidar, Nina; Ferlito, Alfio
Abstract Introduction Laryngeal chondrosarcoma (CS) is a rare indolent malignant tumor. High-grade (G3), dedifferentiated (DD), and myxoid (MY) CSs are considered more aggressive subtypes due to their metastatic potential and relatively poor outcomes. The aim of this systematic review is to evaluate treatment modalities and survival outcomes in patients affected by these rarer CS subtypes. Methods Papers published from January 1, 2000, to August 25, 2024, describing cases of laryngeal G3, DD, and MY CS were included. Results A total of 38 patients (15 G3, 13 DD, and 10 MY) were selected. Cricoid cartilage was the most common site of origin. Total laryngectomy (TL) was often performed. Primary conservative approaches in 42.8% of patients were followed by loco-regional recurrence. Conclusions Aggressive subtypes of CS require a radical approach because of the higher rate of loco-regional and distant recurrences compared to low-grade CS. TL with radical intent is the most common treatment, and adjuvant therapy should be considered after careful multidisciplinary discussion.
Development and usability testing of a multifaceted intervention to reduce low-value injury care
(2025-01-07) Bérubé, Mélanie; Lapierre, Alexandra; Sykes, Michael; Grimshaw, Jeremy; Turgeon, Alexis F.; Lauzier, François; Taljaard, Monica; Stelfox, Henry T.; Witteman, Holly; Berthelot, Simon; Mercier, Éric; Gonthier, Catherine; Paquet, Jérôme; Fowler, Robert; Yanchar, Natalie; Haas, Barbara; Lessard-Bonaventure, Paule; Archambault, Patrick; Gabbe, Belinda; Guertin, Jason R.; Ouyang, Yougdong; Moore, Lynne
Abstract Background Multifaceted interventions that address barriers and facilitators have been shown to be most effective for increasing the adoption of high-value care, but there is a knowledge gap on this type of intervention for the de-implementation of low-value care. Trauma is a high-risk setting for low-value care, such as unnecessary diagnostic imaging and the use of specialized resources. The aim of our study was to develop and assess the usability of a multifaceted intervention to reduce low-value injury care. Methods We used the Consolidated Framework for Implementation Research and the Expert Recommendations for Implementing Change tool as theoretical foundations to identify barriers and facilitators, and strategies for the reduction of low-value practices. We designed an initial prototype of the intervention using the items of the Template for Intervention Description and Replication. The prototype’s usability was iteratively tested through four focus groups and four think-aloud sessions with trauma decision-makers (n = 18) from seven Level I to Level III trauma centers. We conducted an inductive analysis of the audio-recorded sessions to identify usability issues and other barriers and facilitators to refine the intervention. Results We identified barriers and facilitators related to individual characteristics, including knowledge and beliefs about low-value practices and the de-implementation process, such as the complexity of changing practices and difficulty accessing performance feedback. Accordingly, the following intervention strategies were selected: involving governing structures and leaders, distributing audit & feedback reports on performance, and providing educational materials, de-implementation support tools and educational/facilitation visits. A total of 61 issues were identified during the usability testing, of which eight were critical, 33 were moderately important, and 18 were minor. These issues led to numerous improvements, including the addition of information on the drivers and benefits of reducing low-value practices, changes in the definition of these practices, the addition of proposed strategies to facilitate de-implementation, and the tailoring of educational/facilitation visits. Conclusions We designed and refined a multifaceted intervention to reduce low-value injury care using a process that increases the likelihood of its acceptability and sustainability. The next step will be to evaluate the effectiveness of implementing this intervention using a pragmatic cluster randomized controlled trial. Trial registration This protocol has been registered on ClinicalTrials.gov (February 24th 2023, #NCT05744154, https://clinicaltrials.gov/ct2/show/NCT05744154 ).
Troubling the Pixel
(2025-01-09) Yeomans, Tanya Michelle; McDermid, Greg John; Mac Namara, Aoife; Stadnyk, Tricia; Xu, Lincoln Linlin
Monitoring vegetation recovery in forested environments can be done effectively with satellite time series data. However, most research in this space has relied on Landsat imagery, which has a 30-meter pixel size. Emerging CubeSat technology has much finer spatial resolution and offers new possibilities for monitoring vegetation on small industrial disturbances such as well pads and seismic lines. These features are associated with hydrocarbon exploration and are some of the most extensive disturbances in Alberta’s forests. We used PlanetScope satellite imagery to classify vegetation on small industrial disturbance features across a 309-km2 study area in northern Alberta as either growing or declining, and validated our results with LiDAR data. We found that recovery classification on medium-sized well pad features was significantly better than for medium and narrow linear features. We also found that disturbances in some ecosite types (low-density treed wetland, upland mesic, and upland dry sites) were easier to classify than others (transitional and wetland treed) and that linear features oriented in a north-south direction were easier to classify than those oriented east-west. Our research demonstrated that 58% of pixels on disturbed linear features in our study area displayed some degree of spectral regeneration, alongside 76% of the evaluated pixels on wellpads. We believe that the privilege of working with this emergent imagery comes with a responsibility to think deeply on how we use, transform, and interpret the data. To investigate the intersection between landscape, technology, and people, we employed arts-based research methods to trouble the pixel – the fundamental data unit in our remote-sensing research. By creating a textile pixel and documenting it in our study area, we were able to reflect on the parallel methodologies at play in our work, and to identify practical interventions into our scientific practice that allows us to more deeply engage with our data. This includes providing care instructions for our scientific products, slowing down our processes with manual tasks, and dedicating time to witness our data in-situ. Our hope is that through sharing our experiments in investigating our positionality to remote sensing, others are encouraged to reflect on their own practices.
First Measurement of Antihydrogen Free Fall Using a Radial Time Projection Chamber
(2025-01-08) Woosaree, Pooja Devi; Friesen, Timothy; Gomes da Rocha, Claudia; Wieser, Michael E
Using antihydrogen, an apparatus known as ALPHA-g was designed to test Einstein's Weak Equivalence Principle (WEP), where the acceleration due to gravity that a body experiences is independent of its structure or composition. A measurement of the gravitational mass of antimatter has never been done before, as previous experiments used charged particles, which meant the experiments were dominated by electromagnetic forces. The ALPHA-g apparatus uses electrically neutral antihydrogen atoms produced in a vertical Penning-Malmberg trap and trapped in a magnetic minimum trap. By measuring the antihydrogen annihilation positions after a controlled magnetic release of the atoms, the gravitational mass of antihydrogen can be determined. Annihilation positions are reconstructed using a radial time projection chamber (rTPC) surrounding the trapping volume. ALPHA-g was used to complete a successful run in 2022 in the pursuit of measuring the gravitational mass of antihydrogen. The results of this experiment are discussed in this thesis To accurately determine vertical annihilation positions used in the gravity measurement, precise detector calibrations are needed. A laser calibration system was developed and used to gather drift time data in the rTPC, which resulted in drift time measurements and the Lorentz displacement, both of which were used in vertex reconstruction analyses to accurately determine the antihydrogen annihilation positions. Simulations were used to determine the expected electron drift time and Lorentz displacement. Using a Garfield++ toolkit, these observables were simulated from electrons drifting through the gas portion of the ALPHA-g rTPC. Further improvements were made to the reconstruction software to optimise the detector resolution and the number of reconstructed vertices. These methods ultimately led to a free fall direction experiment that concluded antihydrogen fell down on Earth. The experiment was also used to make a preliminary measurement on the gravitational acceleration of a_g = (0:75+/-0:13(statistical + systematic)+/-0:16(simulation))g, where g = 9:81 m/s^2 [1]. Further precision measurements are underway using ALPHA-g to precisely determine the gravitational mass of antihydrogen. Measuring the free-fall direction and gravitational mass of antihydrogen leads the way to a better understanding of the fundamental symmetries in nature, such as the matter-antimatter asymmetry.