The purpose of this systematic review was to study whether contrast sensitivity assessment in people with diabetes could be a reliable test in early detection of diabetic retinopathy. A systematic ...

The aim of our study was to compare computer visual syndrome (CVS) in a tweenager student population who use tablets and laptops only to play versus CVS in tweenagers who use these digital devices at school to study, in addition to playing. The tests performed were a validated survey for children for the detection of CVS and accommodative and vergence tests. The CVS item questionnaire was divided into four main groups based on questions concerning the following: (I) the digital device usage time, (II) musculoskeletal and ergonomic nature, (III) visual symptoms, and (IV) ocular surface symptoms. The high-demand digital device group showed worse punctuation in all item groups. From the optometric perspective, when the subjects were classified according to the CVS, high-demand participants presented a clear tendency to exophoria with statistically significant differences in distance vision (−1.94 ± 4.48 Δ) and near vision (−5.78 ± 8.62 Δ) (p < 0.01). Our results establish a relationship between the increased use of electronic devices and computer vision syndrome in the preadolescent population. In addition, this situation is related to the presence of visual, accommodative, and binocular dysfunctions that could affect the efficiency of the visual system.

This study evaluated the effectiveness of hyaluronic acid and trehalose (HA/trehalose) eyedrops in managing dry eye disease (DED) symptoms by measuring tear stability and administering a DED questionnaire. Sixty patients were treated with either HA/trehalose eyedrops (Tear A) or carmellose sodium eyedrops (Tear B) as controls. The tear breakup time (TBUT) and non-invasive breakup time (NIBUT) were monitored, and patients completed the standard patient evaluation of eye dryness (SPEED) questionnaire. After two months of twice-daily applications, patients treated with the HA/trehalose eyedrops demonstrated significant improvements in the NIBUT (12.98 ± 3.22 s) and TBUT (12.95 ± 2.98 s), indicating increased tear stability. Moreover, they reported lower dry eye sensation (6.70 ± 4.94 SPEED score points), suggesting a reduction in DED symptoms. These findings underscore the efficacy of HA/trehalose eyedrops in improving both the objective and subjective signs of DED, with twice-daily application enhancing ocular surface conditions and reducing patient-reported symptoms.

Purpose: To determine whether patients with type 1 diabetes mellitus (T1DM), without any sign of diabetic retinopathy, have any alteration in Contrast Sensitivity Function (CSF), in relation to patients without this disease, and whether CSF assessment in three different light conditions can be an effective test in the early detection of diabetic retinopathy. Methods: A prospective, cross-sectional, case-control study was preformed including 80 patients (40 with T1DM without diabetic retinopathy and 40 controls) between 11 and 47 years old. CSF was assessed at four spatial frequencies (3, 6, 12 and 18 cycles/degree) using the CSV-1000E test, under three light conditions: high (550 lx), medium (200 lx) and low (< 2 lx). Results: A lower CSF in the T1DM group was found at the three light conditions studied. The most spatial frequency affected was 18 cpd, 0.08 log units (p = 0.048) in high, 0.10 log units (p = 0.010) in medium (p = 0.010) and 0.16 log units (p < 0.001) in low-light conditions in mean CS values. The least spatial frequency affected was 3 cpd (p > 0.05 in all three light conditions). Conclusion: Patients with T1DM, without diabetic retinopathy, presented a loss of CS to sine-wave gratings, with respect to people with the same characteristics without the disease, mainly at medium and high frequencies, and in medium and low-light conditions.

<mml:math display="inline"><mml:msup><mml:mi mathvariant="normal">Tl</mml:mi><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math>Tl+ reduction on gramicidin-modified dioleoylphosphatidylcholine-coated mercury electrodes has been studied by the impedance method in different experimental conditions. On one hand, experiments at twelve gramicidin concentrations in 0.1 M KCl solutions have been performed in order to clarify whether radial diffusion plays some role. On the other hand, KCl, <mml:math display="inline"><mml:msub><mml:mo>KNO</mml:mo><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub><mml:mo>,</mml:mo></mml:math>KNO3, <mml:math display="inline"><mml:msub><mml:mi mathvariant="normal">KClO</mml:mi><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub><mml:mo>,</mml:mo></mml:math>KClO4, <mml:math display="inline"><mml:msub><mml:mi mathvariant="normal">MgCl</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:mo>,</mml:mo></mml:math>MgCl2, and <mml:math display="inline"><mml:msub><mml:mi mathvariant="normal">CaCl</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>CaCl2 solutions have been used as supporting electrolyte to study the influence of ion nature on both the mass transfer and the electron transfer of the process. In all the cases the frequency dependence of the admittance data fits well to a Randles circuit and the Warburg coefficient, σ, and the irreversibility coefficient, <mml:math display="inline"><mml:msup><mml:mi>p</mml:mi><mml:mrow><mml:mo>′</mml:mo></mml:mrow></mml:msup><mml:mo>,</mml:mo></mml:math>p′, can be obtained at every dc potential. However, the potential dependence of σ can only be explained if a mechanism is assumed, including two chemical steps, one preceding and one following the electron transfer (CEC mechanism) even at very high gramicidin concentrations. The impedance equations for reactions on partially blocked electrodes have been deduced, but the results do not conform completely to this model, so other explanations are proposed for the origin of the two chemical steps. Moreover, the standard rate constant, <mml:math display="inline"><mml:msup><mml:mi>k</mml:mi><mml:mrow><mml:mi mathvariant="normal">s</mml:mi></mml:mrow></mml:msup><mml:mo>,</mml:mo></mml:math>ks, and the charge transfer coefficient, α, for the electron transfer were obtained from <mml:math display="inline"><mml:msup><mml:mi>p</mml:mi><mml:mrow><mml:mo>′</mml:mo></mml:mrow></mml:msup><mml:mo>.</mml:mo></mml:math>p′. These parameters are not sensitive to gramicidin concentration or to the nature of the supporting electrolyte. On the contrary, the mass transfer parameters are strongly dependent on these variables. The behavior can be understood at the light of the mechanisms for ion movement in biomembranes. © 2001 The Electrochemical Society. All rights reserved.