Ocular Pulse Amplitude Correlates With Ocular Rigidity at Native IOP Despite the Variability in Intraocular Pulse Volume With Each Heartbeat.

Purpose: The purpose of this study was to assess ocular coat mechanical behavior using controlled ocular microvolumetric injections (MVI) of 15 µL of balanced salt solution (BSS) infused over 1 second into the anterior chamber (AC) via a syringe pump. Methods: Intraocular pressure (IOP) was continuously recorded at 200 Hz with a validated implantable IOP telemetry system in 7 eyes of 7 male rhesus macaques (nonhuman primates [NHPs]) during 5 MVIs in a series at native (3 trials), 15 and 20 mm Hg baseline IOPs, repeated in 2 to 5 sessions at least 2 weeks apart. Ocular rigidity coefficients (K) and ocular pulse volume (PV) were calculated for each trial. Data were averaged across sessions within eyes; PV was analyzed with a three-level nested ANOVA, and parameter relationships were analyzed with Pearson Correlation and linear regression. Results: After MVI at native baseline IOP of 10.4 ± 1.6 mm Hg, IOP increased by 9.1 ± 2.8 mm Hg (∆IOP) at a 9.6 ± 2.7 mm Hg/s slope, ocular pulse amplitude (OPA) was 0.70 ± 0.13 mm Hg on average; the average K was 0.042 ± 0.010 µL-1 and average PV was 1.16 ± 0.43 µL. PV varied significantly between trials, days, and eyes (P ≤ 0.05). OPA was significantly correlated with K at native IOP: Pearson coefficients ranged from 0.71 to 0.83 (P ≤ 0.05) and R2 ranged from 0.50 to 0.69 (P ≤ 0.05) during the first trial. Conclusions: The MVI-driven ∆IOP and slope can be used to assess ocular coat mechanical behavior and measure ocular rigidity. Translational Relevance: Importantly, OPA at native IOP is correlated with ocular rigidity despite the significant variability in PV between heartbeats.

Ocular Complications after COVID-19 Vaccination, Vaccine Adverse Event Reporting System.

In December 2020, the U.S. Food and Drug Administration licensed COVID-19 vaccines for emergency use authorization. We investigated the ocular adverse event reports in patients reported to the Vaccine Adverse Event Reporting System (VAERS) following vaccination against COVID-19. We searched the VAERS database for U.S. reports among persons who received COVID-19 vaccines between December 2020 and December 2021. Our goal was to analyze and quantify the ocular adverse events submitted to VAERS to provide clinicians and researchers with a broader view of these ocular side effects. During the analysis period, VAERS received 55,313 adverse event reports and, after data cleaning, 6688 reports met the inclusion criteria. Note that 2229 (33.33%) adverse events were classified as cases of eyelid swelling, ocular hyperemia and conjunctivitis, 1785 (26.69%) as blurred vision and 1322 (19.77%) as visual impairment. Females accounted for 73.8% of adverse event reports and the age group between 40 and 59 years had the most frequent adverse events. A higher proportion of these adverse events reported to VAERS was linked with the Janssen and Moderna COVID-19 vaccines. At the time of vaccination, a high proportion of patients reported conditions like allergies, hypertension, diabetes, thyroid disease, vascular and other autoimmune diseases. A review of these data suggests a possible association between COVID-19 vaccines and ocular adverse events. Physicians are cautioned not only to be aware of this potential problem, but to check any underlying patient conditions, and to carefully document in VAERS within a few weeks of vaccination. Future COVID-19 vaccine safety studies in healthy subjects would help clarify the vaccine's safety profile.

Selective Ablation of Dehydrodolichyl Diphosphate Synthase in Murine Retinal Pigment Epithelium (RPE) Causes RPE Atrophy and Retinal Degeneration.

Patients with certain defects in the dehydrodolichyl diphosphate synthase (DHDDS) gene (RP59; OMIM #613861) exhibit classic symptoms of retinitis pigmentosa, as well as macular changes, suggestive of retinal pigment epithelium (RPE) involvement. The DHDDS enzyme is ubiquitously required for several pathways of protein glycosylation. We wish to understand the basis for selective ocular pathology associated with certain DHDDS mutations and the contribution of specific ocular cell types to the pathology of mutant Dhdds-mediated retinal degeneration. To circumvent embryonic lethality associated with Dhdds knockout, we generated a Cre-dependent knockout allele of murine Dhdds (Dhddsflx/flx). We used targeted Cre expression to study the importance of the enzyme in the RPE. Structural alterations of the RPE and retina including reduction in outer retinal thickness, cell layer disruption, and increased RPE hyper-reflectivity were apparent at one postnatal month. At three months, RPE and photoreceptor disruption was observed non-uniformly across the retina as well as RPE transmigration into the photoreceptor layer, external limiting membrane descent towards the RPE, and patchy loss of photoreceptors. Functional loss measured by electroretinography was consistent with structural loss showing scotopic a- and b-wave reductions of 83% and 77%, respectively, at three months. These results indicate that RPE dysfunction contributes to DHDDS mutation-mediated pathology and suggests a more complicated disease mechanism than simply disruption of glycosylation.

Role of Translational Attenuation in Inherited Retinal Degeneration.

Purpose: We reported previously that retinas of mice with inherited retinal degeneration make less protein than retinas of normal mice. Despite recent studies suggesting that diminished protein synthesis rates may contribute to neurologic disorders, a direct link between protein synthesis rates and the progression of neurodegeneration has not been established. Moreover, it remains unclear whether reduced protein synthesis could be involved in retinal pathogenesis. Dysregulation of AKT/mTOR signaling has been reported in the retina during retinal degeneration, but to what extent this signaling contributes to translational attenuation in these mice remains uncertain. Methods: C57BL/6J and rd16 mice were subcutaneously injected with anisomycin to chronically inhibit protein synthesis rates. An AAV2 construct encoding constitutively active 4ebp1 was subretinally delivered in wildtype animals to lower protein synthesis rates. 4ebp1/2 were knocked out in rd16 mice. Results: Anisomycin treatment lowered retinal translation rates, accelerated retinal degeneration in rd16 mice, and initiated cell death in the retinas of C57BL/6J mice. AAV-mediated transfer of constitutively active 4ebp1-4A into the subretinal space of wildtype animals inhibited protein synthesis, and led to reduced electroretinography amplitudes and fewer ONL nuclei. Finally, we report that restoring protein synthesis rates by knocking out 4ebp1/2 was associated with an approximately 2-fold increase in rhodopsin levels and a delay in retinal degeneration in rd16 mice. Conclusions: Our study indicates that protein synthesis inhibition is likely not a cell defense mechanism in the retina by which deteriorating photoreceptors survive, but may be harmful to degenerating retinas, and that restoring protein synthesis may have therapeutic potential in delaying the progression of retinal degeneration.

Near and distance stereopsis restoration in amblyopia with S3D computer treatment / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the effect of stereoscopic 3D (S3D) technology as a visual training system in children with amblyopia. METHODS:Totally 30 children,aged 4-16 years old,18 with ametropic amblyopia ( AMA ), and 12 with anisometropic amblyopia(ANA) were recruited in this study. A binocular 3D shutter glasses technology visual training system was used for training trials. Each training time lasted 1h,and the number of training trials totaled 33 (mean士SD:32士8) times on average,per-person. Before and after each training trial, the best corrected visual acuity ( BCVA) of each eye, range of fusion by synoptophore, as well as near and distance stereopsis acuity by Yan Shaoming random - dot test and synoptophore respectively was measured. RESULTS: A significant difference was found pre- and post treatment in BCVA in both kinds of amblyopia studied. Significant improvement was also found in fusion range and stereopsis acuity. The improvement of fusion range and stereopsis recovery could be seen in ANA than in AMA patients. The near stereopsis acuity recovery in ANA group might more easily to regain stereoacuity at near than in AMA group. CONCLUSION: S3D display vision training systems are indicated for the recovery of stereoacuity in children with amblyopia.