Vision (Switzerland)最新文献

Retinitis pigmentosa (RP) encompasses inherited retinal dystrophies, appearing either as an isolated eye condition or as part of a broader systemic syndrome, known as syndromic RP. In these cases, RP includes systemic symptoms impacting other organs, complicating diagnosis and management. This review highlights key systemic syndromes linked with RP, such as Usher, Bardet-Biedl, and Alström syndromes, focusing on genetic mutations, inheritance, and clinical symptoms. These insights support clinicians in recognizing syndromic RP early. Ocular signs like nystagmus and congenital cataracts may indicate systemic disease, prompting genetic testing. Conversely, systemic symptoms may necessitate eye exams, even if vision symptoms are absent. Understanding the systemic aspects of these syndromes emphasizes the need for multidisciplinary collaboration among ophthalmologists, pediatricians, and other specialists to optimize patient care. The review also addresses emerging genetic therapies aimed at both visual and systemic symptoms, though more extensive studies are required to confirm their effectiveness. Overall, by detailing the genetic and clinical profiles of syndromic RP, this review seeks to aid healthcare professionals in diagnosing and managing these complex conditions more effectively, enhancing patient outcomes through timely, specialized intervention.

Background: The outcomes of pediatric glaucoma suspects with a history of ocular trauma remains unknown; we describe the rate of conversion to glaucoma of this population of patients at a research-intensive academic center.

Methods: We conducted a retrospective case series of pediatric patients with a history of open- or closed-globe trauma who were being monitored as pediatric glaucoma suspects at the Wilmer Eye Institute between 2005 and 2016.

Results: A total of 62 eyes from 62 patients with a history of ocular trauma were identified with a median age at presentation of 9.7 years (7.8 years) and a median follow-up of 2.7 (5.8 years). There were 29 eyes (46.8%) with open-globe injuries and 33 eyes (53.2%) with closed-globe injuries. A higher proportion of eyes that sustained closed-globe injuries were started on topical therapy for persistent ocular hypertension than eyes that sustained open-globe injuries (36.4% versus 10.3%, X² = 5.6976, p = 0.017). Five eyes (8.1%) developed glaucoma during the follow-up period, all of which had a history of closed-globe injury (15.2%, X² = 4.7794, p = 0.029). Four eyes of these eyes underwent glaucoma-related surgical intervention. Most eyes (3/5, 60%) that went on to develop post-traumatic glaucoma had undergone additional and/or concurrent intraocular surgical interventions to address sequelae of ocular trauma, such as traumatic cataract and retinal detachment.

Conclusions: All eyes that developed glaucomatous damage or underwent glaucoma-related surgical intervention in this cohort of patients with a history of ocular trauma were those that had sustained close-globe injuries. No eyes that sustained open-globe injury progressed to glaucoma.

The appearance of an object triggers an orienting gaze movement toward its location. The movement consists of a rapid rotation of the eyes, the saccade, which is accompanied by a head rotation if the target eccentricity exceeds the oculomotor range and by a slow eye movement if the target moves. Completing a previous report, we explain the numerous points that lead to questioning the validity of a one-to-one correspondence relation between measured physical values of gaze or head orientation and neuronal activity. Comparing the sole kinematic (or dynamic) numerical values with neurophysiological recordings carries the risk of believing that the activity of central neurons directly encodes gaze or head physical orientation rather than mediating changes in extraocular and neck muscle contraction, not to mention possible changes happening elsewhere (in posture, in the autonomous nervous system and more centrally). Rather than reducing mismatches between extrinsic physical parameters (such as position or velocity errors), eye and head movements are behavioral expressions of intrinsic processes that restore a poly-equilibrium, i.e., balances of activities opposing antagonistic visuomotor channels. Past results obtained in cats and monkeys left a treasure of data allowing a synthesis, which illustrates the formidable complexity underlying the small changes in the orientations of the eyes and head. The aim of this synthesis is to serve as a new guide for further investigations or for comparison with other species.

Objectives: The goal was to study the ellipsoid zone (EZ) as a structural biomarker for final visual outcomes after pharmacological intervention in center-involving diabetic macular edema (DME) and surgical intervention for full-thickness macular holes (FTMHs).

Methods: This was a tertiary care center-based retrospective study. After sample size calculations, data from 64 consecutive cases were collected, with subjects aged between 40 and 60 years. Thirty-two cases of DME with anti-vascular endothelial growth factor (VEGF) therapy and 32 cases of FTMHs with successful macular hole surgery (MHS) were studied. Spectral-domain optical coherence tomography (SD-OCT) data were collected. Measurements of EZ defects documented at the time of presentation and 12 weeks after intervention were analyzed using the caliper function of the machine. EZ restoration was graded, and a Pearson correlation analysis was performed.

Results: Mean logMAR VA decreased after intravitreal therapy (IVT) from 1.12 ± 0.22 pre-intervention to 0.81 ± 0.41 post-intervention and after MHS, from 1.05 + 0.25 to 0.62 + 0.11 (p < 0.001). EZ disruption reduced from 73.4% to 19.4% after IVT and from 67% to 19.3% after MHS. DME and MHS postoperative visual acuity and residual EZ defect were observed to have a statistically significant linear correlation (r = 0.794, p < 0.001 and r = 0.894, p < 0.001, respectively). The EZ was found to be an excellent structural biomarker for final BCVA (area under curve = 0.95 for DME and 1.00 for MHS).

Conclusion: Notable EZ restoration results were obtained from pharmacological and surgical interventions. The EZ proves to be a critical structural biomarker for predicting visual outcomes in center-involving DME and MHS.

This study investigates colour vision deficits in children with amblyopia by employing a computerized colour vision test with varying stimulus sizes (1°, 2°, and 3°). The aim is to delineate the impact of amblyopia on colour discrimination in children and to determine the effectiveness of the computerized colour vision test in detecting these deficits. The study involved 40 participants, divided into 20 children with amblyopia and 20 without amblyopia (control group). Our findings reveal that, during binocular viewing, children with amblyopia exhibit significant impairments in colour vision both for red-green and blue-yellow axes, primarily for 1° chromatic stimuli, but not for larger stimuli (2° and 3°). These findings offer valuable insight into the functional visual limitations in pediatric amblyopia, potentially guiding more targeted clinical assessments and interventions.

Mental imagery is claimed to underlie a host of abilities, such as episodic memory, working memory, and decision-making. A popular view holds that mental imagery relies on the perceptual system and that it can be said to be 'vision in reverse'. Whereas vision exploits the bottom-up neural pathways of the visual system, mental imagery exploits the top-down neural pathways. But the contribution of some other neural areas remains overlooked. In this article, I explore important contributions of the hippocampus, a neural area traditionally associated with episodic memory, to mental imagery formation. I highlight evidence which supports the view that the hippocampus contributes to the spatial model used for mental imagery and argue that we can distinguish different hippocampal circuits which contribute to different kinds of imagery, such as object imagery, scene imagery, and imagery with a temporal aspect. This has significant upshots for mental imagery research, as it opens a new avenue for further research into the role of the hippocampus in a variety of imagery tasks.

The present work characterized the effects of hydration on the viscoelastic tensile properties of the sclera. Scleral strips were dissected from the posterior region near the optic nerve head of porcine eyes in the superior-inferior direction. The samples were divided into four hydration groups and their mechanical response was characterized by conducting uniaxial tensile stress-relaxation experiments. An exponential relation and logarithmic expression were used to numerically represent the experimental measurements during the ramp and relaxation periods, respectively. A nonlinear increase in the tensile stress during the ramp period was observed for all strips. Furthermore, it was found that dehydrated specimens had stiffer tensile properties. In particular, it was observed that the maximum and equilibrium stresses increased significantly with decreasing hydration. Furthermore, it was found that the viscoelastic tensile response of porcine scleral strips at different hydration levels could be collapsed onto a single normalized curve. The findings of the present work showed that hydration had significant effects on the viscoelastic tensile properties of sclera.

Virtual reality (VR) can challenge the visual system, leading to temporary oculomotor changes, though the degree of change varies among individuals. While the vergence and accommodation system plays a crucial role in VR perception, it remains unclear whether individuals whose visual functions fall outside clinical norms experience larger changes. Thus, our study aimed to investigate whether changes in vergence and accommodation responses following VR gameplay differ between individuals with and without non-strabismic binocular and accommodative disorders. To assess this, both subjective and objective measurements were conducted before and after 20 min of playing Beat Saber. Results revealed significant alterations across both subjective measurements-near point of convergence and near point of accommodation-and objective measurements, including eye refraction, accommodation lag, and accommodative microfluctuations at far. Moreover, individuals with non-strabismic binocular and accommodative disorders exhibited larger accommodative microfluctuations at far compared to the control group. Overall, these findings indicate that considering individual differences in vergence and accommodation responses is important when evaluating the impact of VR on the visual system and can be helpful in the design and use of VR systems, particularly for individuals with binocular and accommodative disorders.

In 1975, Brit J [...].

Dry eye disease (DED) has become increasingly prevalent in the digital era, largely due to prolonged screen exposure. The excessive use of digital devices contributes to inappropriate blink frequency and dynamics, leading to ocular surface dryness and discomfort. Additionally, digital screen use has broader implications for systemic health, including visual strain, headaches, and disrupted circadian rhythms caused by blue light exposure. Previous studies have shown that prolonged screen time correlates with altered blink frequency and increased symptom severity in DED patients, exacerbating the imbalance in tear film production and evaporation. Blinking dynamics, particularly blink rate and completeness, are crucial in maintaining ocular surface moisture. Incomplete blinking impairs meibomian gland function, reducing lipid secretion, which is essential for preventing tear evaporation. Raising patient awareness through educational material, ergonomic adjustments, and blinking exercises has been shown to mitigate these effects. Digital tools that provide targeted educational interventions can be particularly effective in improving blink dynamics and overall ocular comfort. This study evaluates the efficacy of digital applications in optimizing blinking dynamics and enhancing tear film stability. The findings suggest that these innovations improve patient outcomes by encouraging healthier eye care practices. However, further research is needed to assess their long-term impact across diverse populations.