10 research outputs found

    TECNOFOBIA EN LAS TIC: SUPERANDO MITOS EN EL USO DE PANTALLAS DIGITALES PARA EL APRENDIZAJE

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    A medida que la tecnología redefine la educación a través de las Tecnologías de la Información y Comunicación (TIC), el aumento en el uso de pantallas digitales genera inquietudes sobre sus posibles efectos sobre la salud visual. Al analizar la evidencia científica, este trabajo desmonta mitos y aclara conceptos erróneos. No se trata del objeto observado en sí, sino factores conductuales como la distancia, la iluminación y las pausas, además del tiempo al aire libre, los responsables de los problemas visuales. Las pantallas como herramientas educativas no presentan mayores riesgos que los materiales impresos cuando se usan adecuadamente. En este panorama tecnológico en constante evolución, es crucial fomentar la alfabetización digital y el uso equilibrado de las TIC, empoderando a estudiantes y educadores para aprovechar al máximo los beneficios que estas herramientas modernas pueden ofrecer

    Is the capsular bag perimeter round or elliptical?

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    Purpose: To report findings that could suggest an elliptical shape of the capsular bag. Methods: Five eyes of three patients with axial length greater than 24 mm underwent phacoemulsification cataract surgery with plate-haptic multifocal toric intraocular lens (IOL) implantation oriented in the vertical meridian. Results: In all cases, correct orientation of the IOLs was verified 30 minutes after surgery. After 24 hours, all eyes demonstrated unwanted rotation of the IOLs ranging from 15 to 45 degrees. The IOLs remained stable in the new position in all cases until adhesion of the capsular bag took place. Conclusion: These observations could suggest that the perimeter of the capsular bag has an elliptical shape. Therefore, the IOL tends to become fixated in a meridian of the capsular bag that best fits the diagonal diameter of the IOL

    A New Deep Learning Algorithm with Activation Mapping for Diabetic Retinopathy: Backtesting after 10 Years of Tele-Ophthalmology

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    We report the development of a deep learning algorithm (AI) to detect signs of diabetic retinopathy (DR) from fundus images. For this, we use a ResNet-50 neural network with a double resolution, the addition of Squeeze–Excitation blocks, pre-trained in ImageNet, and trained for 50 epochs using the Adam optimizer. The AI-based algorithm not only classifies an image as pathological or not but also detects and highlights those signs that allow DR to be identified. For development, we have used a database of about half a million images classified in a real clinical environment by family doctors (FDs), ophthalmologists, or both. The AI was able to detect more than 95% of cases worse than mild DR and had 70% fewer misclassifications of healthy cases than FDs. In addition, the AI was able to detect DR signs in 1258 patients before they were detected by FDs, representing 7.9% of the total number of DR patients detected by the FDs. These results suggest that AI is at least comparable to the evaluation of FDs. We suggest that it may be useful to use signaling tools such as an aid to diagnosis rather than an AI as a stand-alone tool

    Weighted nonnegative tensor factorization for atmospheric tomography reconstruction

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    Context. Increasing the area on the sky over which atmospheric turbulences can be corrected is a matter of wide interest in astrophysics, especially when a new generation of extremely large telescopes (ELT) is to come in the near future. Aims. In this study we tested if a method for visual representation in three-dimensional displays, the weighted nonnegative tensor factorization (WNTF), is able to improve the quality of the atmospheric tomography (AT) reconstruction as compared to a more standardized method like a randomized Kaczmarz algorithm. Methods. A total of 1000 different atmospheres were simulated and recovered by both methods. Recovering was computed for two and three layers and for four different constellations of laser guiding stars (LGS). The goodness of both methods was tested by means of the radial average of the Strehl ratio across the field of view of a telescope of 8m diameter with a sky coverage of 97.8 arcsec. Results. The proposed method significantly outperformed the Kaczmarz in all tested cases (p ≤ 0.05). In WNTF, three-layers configuration provided better outcomes, but there was no clear relation between different LGS constellations and the quality of Strehl ratio maps. Conclusions. The WNTF method is a novel technique in astronomy and its use to recover atmospheric turbulence profiles was proposed and tested. It showed better quality of reconstruction than a conventional Kaczmarz algorithm independently of the number and height of recovered atmospheric layers and of the constellation of laser guide star used. The WNTF method was shown to be a useful tool in highly ill-posed AT problems, where the difficulty of classical algorithms produce high Strehl value maps

    Intravitreal dexamethasone implants for diabetic macular edema

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    AIM: To evaluate the safety and efficacy of a dexamethasone (DEX) intravitreal implant for diabetic macular edema (DME). METHODS: Totally 113 eyes of 84 patients were divided in three subgroups: naive patients (n=11), pseudophakic patients (n=72) and phakic patients (n=30). Inclusive criterion comprised adult diabetic patients with central fovea thickening and impaired visual acuity resulting from DME for whom previous standard treatments showed no improvement in both central macular thickness (CMT) and best corrected visual acuity (BCVA) after at least 3mo of treatment. Outcome data were obtained from patient visits at baseline and at months 1, 3, 5, 9 and 12 after the first DEX implant injection. At each of these visits, patients underwent measurement of BCVA, a complete eye examination and measurement of CMT and macular volume (MV) carried out with optical coherence tomography (OCT) images. RESULTS: Seventy-three eyes (64.5%) received a single implant, 30 (26.5%) received two implants and 10 (9%) received three implants. At baseline, average in BCVA, CMT and MV were 43.5±20.8, 462.8±145 and 12.6±2.5 respectively. These values improved significantly at 1mo (BCVA: 47.2±19.5, CMT: 339.6±120, MV: 11.11±1.4) and 3mo (BCVA: 53.2±18.1, CMT: 353.8±141, MV: 11.3±1.3) (P≤0.05). At 5mo (BCVA: 50.9±19.8, CMT: 425±150, MV: 12.27±2.3), 9mo (BCVA: 48.4±17.6, CMT: 445.5±170, MV: 12.5±2.3) and 12mo (BCVA: 47.7±18.8, CMT: 413.2±149, MV: 12.03±2.5), improvements in the three parameters were no longer statistically significant and decreased progressively but did not reach baseline values. There were no clinical differences between subgroups. Ocular complications were minimal. CONCLUSION: Patients with DEX implants show maximum efficacy at 3mo which then declined progressively, but is still better than baseline values at the end of follow-up
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