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Cardiovascular diseases (CVD) are a predominant health concern globally, emphasizing the need for advanced diagnostic techniques. In our research, we present an avant-garde methodology that synergistically integrates ECG readings and retinal fundus images to facilitate the early disease tagging as well as triaging of the CVDs in the order of disease priority. Recognizing the intricate vascular network of the retina as a reflection of the cardiovascular system, alongwith the dynamic cardiac insights from ECG, we sought to provide a holistic diagnostic perspective. Initially, a Fast Fourier Transform (FFT) was applied to both the ECG and fundus images, transforming the data into the frequency domain. Subsequently, the Earth Mover's Distance (EMD) was computed for the frequency-domain features of both modalities. These EMD values were then concatenated, forming a comprehensive feature set that was fed into a Neural Network classifier. This approach, leveraging the FFT's spectral insights and EMD's capability to capture nuanced data differences, offers a robust representation for CVD classification. Preliminary tests yielded a commendable accuracy of 84%, underscoring the potential of this combined diagnostic strategy. As we continue our research, we anticipate refining and validating the model further to enhance its clinical applicability in resource limited healthcare ecosystems prevalent across the Indian sub-continent and also the world at large. [ABSTRACT FROM AUTHOR]

Aim. Multisystemic physiological changes in pregnancy can result in tear film and refractive changes in the eye. We report dry eye prevalence in pregnant women using Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire. Methods. The SPEED questionnaire was self-administered cross-sectionally to 428 pregnant women (mean age: 26.8 ± 4.4 years) with clinically confirmed pregnancy from two obstetric clinics in Chennai, India. Subjects with predisposing risk factors for dry eye were excluded from the study. Subjects were categorized as normal, moderate, and severe dry eye based on the SPEED score. Results. Among the women, 48.5% of the subjects had symptoms like dryness, grittiness or scratchiness, soreness or irritation, burning or watering, or eye fatigue. About 2.3% had moderate dry eye according to SPEED questionnaire criteria. Eye fatigue was the most reported symptom and was present in 76.4% of women. The symptom frequency score and severity score had a strong and significant correlation (r = 0.95 , P <.001). No significant correlation was noted among SPEED score vs age (r = − 0.02 , P >.05). No significant correlation was found between symptoms of dry eye and gravidity (ρ = − 0.006 , P >.05) and trimester (ρ = 0.38 , P >.05). Binary logistic regression showed that only occupational status and systemic condition was significantly associated with dry eye symptoms. Conclusion. About half the pregnant women at the visit reported having one or more dry eye-related symptoms. As per the composite SPEED questionnaire score, dry eye was not prevalent among pregnant women irrespective of their age, gravidity, and the trimester, but we found a majority of pregnant women reported to have experienced dry eye-related symptoms, though tolerable. Awareness about dry eye during pregnancy will improve eye care seeking behaviour in pregnant women. [ABSTRACT FROM AUTHOR]

This publication represents the summary of results of the doctoral thesis Presbyopia Corrections: Optical, Perceptual and Adaptational Implications presented at the Universidad Complutense de Madrid, Spain. Presbyopia, the physiological inability of the aging crystalline lens to accommodate for objects at near distance, can be treated using a multitude of optical corrections. Systematic evaluation of the visual system's ability to interact with these corrections will help in optimization of their performance. In this thesis we studied optical and perceptual performance of different presbyopic corrections such as alternating vision, monovision and simultaneous vision and the effect of adaptation on perceptual performances. We used custom-developed adaptive optics setup to measure and correct ocular aberrations and projected manipulated images simulating pure simultaneous vision corrections of different far/near energy profiles and near additions. We also developed and validated an on-bench and a hand-held simultaneous vision simulator to optically simulate pure or segmented simultaneous vision corrections. Psychophysical methods were employed to study the changes in perceptual quality and after-effects of adaptation. We performed numerical simulations to predict perceptual performance from the ocular aberrations of the subjects. We demonstrated that mechanism of adaptation to simultaneous vision is similar to that of blur adaptation, influenced mostly by retinal image contrast and that systematic changes in visual and perceptual performance influenced by multifocal design and testing distance. The ocular optics of the subject's eye correlated significantly with visual performance and was associated with the intersubject variability in performance. We found that a cyclopean locus for perception and adaptation, in subjects with different blur magnitude between eyes, influenced by the eyes with better optical quality. The internal code for blur was also influenced by the eye with better optical quality, both in orientation and magnitude. Our results confirm that the existing optical solutions should be chosen based on the subjective needs and the ocular optics would be an ideal starting point to customize optical solutions of presbyopia for optimal performance. We also demonstrated the usefulness of rapid assessment of perception to multifocal designs using the handheld, seethrough simultaneous vision simulator. [ABSTRACT FROM AUTHOR]

Presbyopes can choose today among different corrections to provide them with functional vision at far and near, and the outcomes and patient satisfaction depend on the selection. In this study, we present a binocular and portable vision simulator, based on temporal multiplexing of two synchronized tunable lenses allowing see-through and programmable visual simulations of presbyopic corrections. Seventeen binocular corrections were tested: 3 Monofocal (Far, Intermediate, Near), 4 Simultaneous Vision (bifocal, trifocal), 2 Monovision (far and near in either eye) and 8 Modified Monovision corrections (Simultaneous vision in one eye, Monofocal in the other eye). Perceived visual quality was assessed through the simulated corrections in 8 cyclopleged subjects who viewed a composite realistic visual scene with high contrast letters and a landscape at far (4 m) and a high contrast text at intermediate (66 cm) and near (33 cm) distances. Perceptual scores were obtained on a scale of 0 to 5 (low to high perceived quality). Perceptual preference was assessed by judging 36 random image pairs (6 repetitions) viewed through 9 binocular presbyopic corrections using two-interval forced choice procedures. The average score, across far and near distances, was the highest for Monovision (4.4±0.3), followed by Modified Monovision (3.4±0.1), Simultaneous Vision (3.0±0.1) and Monofocal corrections (2.9±0.2). However, the mean difference between far and near was lower for Simultaneous Vision and Monovision (0.4±0.1 PS) than Modified Monovision (1.8±0.7) or monofocal corrections (3.3±1.5). A strong significant correlation was found between the perceptual scores and the percentages of energy in focus, for each correction and distance (R = 0.64, p<0.0001). Multivariate ANOVA revealed significant influence of observation distances (p<10–9) and patients (p = 0.01) on Perceptual Score. In conclusion, we have developed a binocular portable vision simulator that can simulate rapidly and non-invasively different combinations of presbyopic corrections. This tool has applications in systematic clinical evaluation of presbyopia corrections. [ABSTRACT FROM AUTHOR]

Simultaneous vision is an increasingly used solution for the correction of presbyopia (the age-related loss of ability to focus near images). Simultaneous Vision corrections, normally delivered in the form of contact or intraocular lenses, project on the patient's retina a focused image for near vision superimposed with a degraded image for far vision, or a focused image for far vision superimposed with the defocused image of the near scene. It is expected that patients with these corrections are able to adapt to the complex Simultaneous Vision retinal images, although the mechanisms or the extent to which this happens is not known. We studied the neural adaptation to simultaneous vision by studying changes in the Natural Perceived Focus and in the Perceptual Score of image quality in subjects after exposure to Simultaneous Vision. We show that Natural Perceived Focus shifts after a brief period of adaptation to a Simultaneous Vision blur, similar to adaptation to Pure Defocus. This shift strongly correlates with the magnitude and proportion of defocus in the adapting image. The magnitude of defocus affects perceived quality of Simultaneous Vision images, with 0.5 D defocus scored lowest and beyond 1.5 D scored “sharp”. Adaptation to Simultaneous Vision shifts the Perceptual Score of these images towards higher rankings. Larger improvements occurred when testing simultaneous images with the same magnitude of defocus as the adapting images, indicating that wearing a particular bifocal correction improves the perception of images provided by that correction. [ABSTRACT FROM AUTHOR]