Fellow Eye Research Articles

Long term intraocular pressure fluctuation and epiretinal membrane in patients with glaucoma or glaucoma suspect

Aims/Purpose: The associations between ERM and glaucoma were suggested in several studies. In an animal model undergoing intermittent IOP elevations, a reactive gliosis, a phenotype of ERM, was found in the optic nerve head. We investigated the association between intraocular pressure (IOP) fluctuation and idiopathic ERM in patients with glaucoma or glaucoma suspect.Methods: In this retrospective study, a total of 84 patients with glaucoma or glaucoma suspect were included. Among them, forty one patients had no ERM and forty three patients had ERM. Long‐term fluctuation of IOP was defined as the standard deviation (SD) of IOP at all visits. Patients were divided into two groups according to the median value of SD of IOP: the low IOP fluctuation group and high IOP fluctuation group. Among patients with available heart rate variability (HRV) data, the relationship between the HRV parameter and IOP fluctuation was analysed.Results: Patients with ERM was older and had higher IOP fluctuation and higher proportion of having history of cataract surgery and greater macular thickness (p = 0.018, 0.049, 0.013, < 0.001). The high IOP fluctuation group showed higher proportion of patients with ERM (62.5%) than the low IOP fluctuation group (36.4%, p = 0.028). In the multiple logistic analysis, higher IOP fluctuation group were associated with the presence of ERM (p = 0.047). Among patients with ERM, eyes with stage 3 or 4 ERM had worse visual field defects based on mean deviation than those with stage 1 or 2 ERM (p = 0.025). The high IOP fluctuation group showed higher level of low frequency HRV, an index of sympathetic cardiac control than the low IOP fluctuation group (p = 0.027). Intereye comparison in eyes with ERM and the fellow eyes without ERM, eyes with ERM (2.2 ± 0.9 mmHg) had higher fluctuation of IOP than those without ERM (2.0 ± 0.8 mmHg, p = 0.029).Conclusions: In conclusion, long‐term IOP fluctuation had the relevance to idiopathic ERM in patients with glaucoma or glaucoma suspect. In glaucoma patients with ERM, more advanced stage ERMs were associated with worse visual field damage. Further studies are needed to determine if long‐term IOP fluctuation affects the progression of glaucoma and ERM.

Optical coherence tomography angiography findings after silicone oil tamponade for rhegmatogenous retinal detachment

Aim: To describe retinal structural and microvascular changes using Swept source optical coherence tomography (SS‐OCT) and OCT angiography (OCT‐A) in patients with rhegmatogenous retinal detachment (RRD) treated by vitrectomy (PPV) and silicone oil (SO) tamponade and to identify the final visual acuity (VA) prognostic factors.Methods: In this retrospective study, patients were treated with PPV and SO tamponade for uncomplicated DRR. After SO removal, retinal thickness was assessed by SS‐OCT. The foveal avascular zone (FAZ) area, the fractal dimension (FD), the lacunarity (LAC) and the macular capillary vessel density (VD) in the superficial (PCS) and deep plexuses (PCP) and in the choriocapillaris (CC) were analysed.Results: Thirty‐one eyes were included in this study; 20 eyes (65%) had macula ‘OFF’ RRD. The mean post‐operative final VA was 3.2/10. Outer retinal defect was observed in 74.1% of the operated eyes. Central macular thickness (CMT) and parafoveal thickness were significantly decreased compared with healthy fellow eyes (p = 0.048; p = 0.029). Outer nuclear layer (ONL) and subfoveal choroid were significantly thinned in the operated eyes (p = 0.003; p = 0.017). The FAZ in PCS and PCP and was larger (p = 0.042; p = 0.032), the VD (total, parafoveal and parafoveal) in the PCP were significantly lower (p = 0.004; p = 0.012; p = 0.049) and the lacunarity (LAC) at the PCP level was significantly higher (p = 0.040) in the operated eyes than in the fellow eyes. The final VA was correlated with the defect of the outer retina (p < 0.002) and the VD in PCP (p = 0.0199). The duration of SO tamponade was signifcantly correlated with the outer retinal defect (p = 0.011), the enlargement of FAZ area (p = 0.001) and the VD in DCP (p = 0.002).Conclusion: SIO can lead to structural and vascular retinal ischaemic defect such as enlargement and irregularity of the FAZ and predominant PCP capillary abnormalities. These changes could reflect vascular hypoperfusion in eyes with SO tamponade and may represent a potential cause of retinal thinning and unexplained visual loss.

Interchangeability of bilateral anterior chamber depth in intraocular lens power calculation and its application in unilateral lens subluxation

Aims/Purpose: To assess the interchangeability of bilateral anterior chamber depth (ACD) in intraocular lens (IOL) power calculation, and to evaluate whether using the unaffected fellow eye's ACD can enhance refractive results in unilateral lens subluxation.Methods: Axial length (AL), keratometry (K) and ACD were obtained by IOLMaster 700. In cataract surgery candidates (Group 1), the virtual implantation of the same IOL model was used. The predictive results closest to the Plano of the Kane formula, using the right eye's biometry (AL, K and ACD), served as a benchmark. The results of the corresponding IOL power were further calculated by substituting the left eye's ACD for the right eye's one and compared with the benchmark. Eyes with unilateral lens subluxation (Group 2) underwent in‐the‐bag IOL placement after the capsular hook(s) implantation, with refraction conducted at least 1 month post‐operatively. Prediction errors (PE) of the Kane formula with or without the unaffected fellow eye's ACD were compared.Results: 392 eyes of 196 patients were analysed, including 173 candidates and 23 patients with unilateral subluxated lenses. In Group 1, there was no significant difference in bilateral ACD (p = 0.30). The predictive refraction using the right eye's ACD was −0.16 ± 0.10 diopter (D), and that obtained by the left eye's one was −0.16 ± 0.11 D (p = 0.64), with an absolute difference of 0.03 ± 0.03 D. In Group 2, the ACD was 2.89 ± 0.86 mm of the affected eye and 3.14 ± 0.37 mm of the fellow eye (p = 0.17). The median absolute PE, mean absolute PE and the percentage of PEs within ±0.50 D using the affected eye's ACD were 0.50 D, 0.59 D and 52.17%. Using the unaffected eye's ACD improved the outcomes to 0.45D, 0.52 D and 60.87%.Conclusions: Bilateral ACD values are interchangeable in routine IOL power calculation, and using the unaffected fellow eye's ACD can improve its accuracy in cases of unilateral lens subluxation undergoing in‐the‐bag IOL implantation.

Biometric risk factors for central serous chorioretinopathy

Aims/Purpose: The goal of the present study was to find the biometric parameters associated with the incidence of CSCR.Methods: The study included 66 eyes of 60 consecutive patients that were diagnosed with acute or chronic CSCR between 01.01.2021 and 30.06.2021. Six patients had a binocular disease. All patients had axial length and retinal parameters measured with the spectral domain optical coherence tomography (SD‐OCT) as well as refraction error tested after cycloplegia. Results of the affected eyes were compared with the healthy fellow eyes (39 eyes) and control group (75 eyes) and correlated to the duration of the disease.Results: No significant differences were revealed between axial length of the affected eyes, healthy fellow eyes and controls (23.31 ± 1.06 vs. 23.59 ± 1.20 vs. 23.33 ± 1.19). Distribution of refraction errors was similar in the three analysed groups. Hypermetropic shift was noted in the affected eyes versus controls (p = 0.030); however, no difference was noted in the refraction error between the healthy fellow CSCR eyes and controls (p = 0.418). Both acute and chronic CSCR cases, as well as their fellow eyes, demonstrated significantly greater choroidal thickness compared to healthy individuals (p < 0.001). Longer disease duration was correlated with significant deficit in macular volume and average central retinal thickness (p < 0.05).Conclusions: CSCR is a clinical entity that can occur in patients with every type of refraction error. Shorter axial length of the eyeball is not associated with higher prevalence of CSCR, however increased choroidal thickness is typical of that entity. Longer disease duration is correlated to the loss of retinal thickness and volume.

New technologies for eye care practitioners

Keywords: orthoptics, optometry, visual rehabilitation, visual therapy.In the 1920s, Mary Maddox opened a vision rehabilitation center in London, being considered the first orthoptist (an unknown profession in Spain, whose competences fall on Optics‐Optometry). Her father, Ernest E. Maddox, an ophthalmologist, had developed various instruments to investigate binocular vision. The new discipline seeks to improve the binocular state of the patient, affected by symptomatic tropias or phorias, through exercises that train eye movements, ductions, versions, vergences, fixations and saccades. Amblyopia, on the other hand, is still treated by occlusion of the fellow eye, following practices that began in the 18th century (George L. de Buffon).During the 20th century, orthoptic specialists used different instruments, which have survived to this day, for the diagnosis and treatment of deviations. Perhaps the most advanced of them is the synoptophore, capable of determining objective and subjective deviations, the presence of normal or abnormal correspondences, and the presence of suppression scotoma. The synoptophore is also used in rehabilitation, together with the aperture rule, vectograms or the Brock string. However, in the case of tropias and during the 20th century, orthoptic therapy occupies a very marginal place compared to the surgical solution. The Hubel and Wiesel experiments in the 60s and 70s were interpreted restrictively, rooting concepts such as the so‐called critical period, which discouraged any attempt to treat amblyopia beyond occlusion, particularly in adulthood.However, research carried out from the second half of the 20th century to nowadays provides evidence of the usefulness of vision rehabilitation in the treatment of strabismus and non‐strabismus visual dysfunctions, and in the recovery of amblyopia in adulthood. Basic research led by Dennis M. Levi of the University of California at Berkeley and Robert F. Hess of McGill University, as well as clinical research by the Paediatric Eye Disease Investigator Group, PEDIG, are good examples.New technologies based on computers are currently renewing and revitalizing orthoptic practice, both in diagnosis and treatment. Eye‐trackers combined or not with Virtual Reality allow (a) to record eye movements accurately and objectively, and to identify visual behaviour and deficits, and (b) to train those movements, providing positive feedback to the patient. Screens have evolved from conventional models, later 3D and finally Virtual Reality, allowing dynamic exercises and avoiding other limitations, such as postural ones. Software algorithms adapt the difficulty of the exercises to patient's performance, record therapy compliance, and store the results in the cloud for remote control of home therapy. In addition, gamification techniques allow increasing the patient's motivation and adherence to treatment. These improvements are essential in perceptual learning, the paradigm of the new visual rehabilitation model.

Intraocular pressure measurement and association with corneal biomechanics in patients underwent Descemet's stripping with endothelial keratoplasty: a comparative study.

To compare corneal biomechanical properties and intraocular pressure (IOP) measurements in patients who underwent Descemet's stripping with endothelial keratoplasty (DSEK) with those of the follow healthy eyes. In this retrospective comparative study, a total of 35 eyes of 35 patients who underwent DSEK by a single surgeon from 2015.02 to 2019.12 were enrolled along with their fellow healthy eyes. Corneal biomechanical parameters were assessed at least 3 months post-DSEK using Corneal Visualization Scheimpflug Technology (CST). IOP was measured by CST, Goldmann applanation tonometry (GAT), and MacKay-Marg tonometer. Central corneal thickness (CCT) and stiffness parameter at first applanation (SP-A1) were significantly increased after DSEK when compared to the fellow eyes. In DSEK eyes, biomechanically-corrected intraocular pressure (bIOP) and MacKay-Marg IOP correlated significantly with GAT IOP measurements, with bIOP showed the lowest IOP values. All the IOP values did not correlate with CCT. However, GAT-IOP and MacKay-Marg IOP showed a positive correlation with SP-A1. The corneal stiffness increased after DSEK. Central corneal thickness may have less influence than corneal biomechanics on IOP measurements in eyes after DSEK. Biomechanically-corrected IOP obtained by CST seemed to be lower than other tonometry techniques in DSEK eyes, perhaps because of correction for corneal stiffness, CCT and age.

Investigation of the eyelids with meibography in eyes with gold weight implantation after facial paralysis and comparison with healthy fellow eye

Investigation of the eyelids with meibography in eyes with gold weight implantation after facial paralysis and comparison with healthy fellow eye

Comparative analysis of corneal parameters in simple myopic anisometropia using Scheimpflug technology.

This study aims to investigate the differences in binocular corneal parameters and their interrelation with binocular biometric parameters asymmetry in patients with simple myopic anisometropia, thereby elucidating the influence of myopia process on various corneal parameters. In this cross-sectional study, 65 patients with anisometropia in monocular myopia were included. They were divided into low anisometropia group: 3.00D<Δ spherical equivalent (SE)≤-1.00D (Δ represents the difference between the two eyes, i.e., myopic data minus emmetropic data) and high anisometropia group: ΔSE ≤ -3.00D. Corneal and ocular biometric parameters were measured using Pentacam, Corvis ST, and IOL Master 700. Statistical analyses focused on the binocular corneal parameters asymmetry, using the contralateral emmetropia as a control. The mean age of participants was 18.5 ± 1.3 years, with the average SE for myopia and emmetropia being -2.93 ± 1.09D and -0.16 ± 0.41D, respectively. The central corneal thickness (CCT), flat keratometry (Kf), keratometry astigmatism (Ka), total corneal aberration (6mm) (TOA), surface variance index (ISV), vertical asymmetry index (IVA), stress-strain index (SSI), and first applanation stiffness parameter (SPA1) and ambrosia relational thickness-horizontal (ARTh) showed significant differences between anisometropic fellow eyes (p < 0.05). There were significant differences in ΔIVA, Δ the difference between the mean refractive power of the inferior and superior corneas (I-S), Δ deviation value of Belin/Ambrósio enhanced ectasia display (BAD-D), Δ deformation amplitude ratio max (2mm) (DAR)and Δ tomographic biomechanical index (TBI) (p < 0.05) in two groups. Asymmetry of corneal parameters was correlated with asymmetry of ocular biometric parameters. Anisometropia (ΔSE) was positively correlated with ΔIVA (r = 0.255, p = 0.040), ΔBAD-D (r = 0.360, p = 0.006), and ΔSSI (r = 0.276, p = 0.039) and negatively correlated with ΔDAR (r = -0.329, p = 0.013) in multiple regression analysis. Δ mean keratometry (Km), Δ anterior chamber depth (ACD), and Δ biomechanically corrected intraocular pressure (bIOP) were also associated with binocular corneal differences. Compared to contralateral emmetropia, myopic eyes have thinner corneas and smaller corneal astigmatism. Myopic corneas exhibit relatively more regular surface morphology but are more susceptible to deformation and possess marginally inferior biomechanical properties. In addition, there is a certain correlation between anisometropia and corneal parameter asymmetry, which would be instrumental in predicting the development of myopia.

Morphological and Clinical Characterization of Foveal Bulge Sign Three Years After Retinal Detachment Repair: A Longitudinal Prospective Evaluation.

To evaluate optical-coherence-tomography (OCT)-morphological and clinical parameters three years after primary rhegmatogenous retinal detachment (RRD) repair surgery and the role of postoperative foveal bulge sign. Of the 32 initially enrolled patients with primary RRD 20 (14 fovea-on, 6 fovea-off) completed this prospective study. Preoperatively and 3 years after surgery best corrected visual acuity (BCVA) and OCT including macula status, central retinal thickness (CRT), central choroidal thickness (CCT), thickness of each single retinal layer, integrity of cone-interdigitation-zone (CIZ) and ellipsoid zone (EZ), and presence of foveal bulge were evaluated. Preoperatively fovea-off RRD patients show significantly thinner CCT, inner nuclear layer (INL) and inner plexiform layer (IPL) compared to fovea-on RRD patients, whereas only IPL and INL were significantly thicker compared to the fellow eye. Three years after surgery this thickening recovered. Final BCVA did not differ statistically significantly between fovea-off and fovea-on patients, no difference in CIZ-integrity or presence of foveal bulge was observed. Presence of foveal bulge at 3 years showed significantly better final BCVA and was associated with intact preoperative CIZ-integrity and postoperative EZ- and CIZ-integrity. The preoperative fovea status showed no correlation to the postoperative presence of foveal bulge. Three years after RRD repair retinal layers show similar thickness. The presence of foveal bulge is associated with better final BCVA. Sufficient pre- and postoperative CIZ-integrity as well as postoperative CIZ-integrity seem to be strongly associated with the restoration of foveal bulge. No correlation was found with the preoperative macular status or BCVA.

Relationship between central corneal thickness and inter‐eye disease severity in primary angle closure glaucoma

Aims/Purpose: To determine whether subjects with asymmetric primary angle closure glaucoma (PACG) demonstrate greater central corneal thickness (CCT) asymmetry compared to those with symmetrical disease severity.Methods: The following clinical data were retrospectively extracted from the case records of 281 PACG subjects: presenting intraocular pressure (IOP), visual field mean deviation (MD) at presentation, CCT, anterior chamber depth (ACD), and axial length (AL). The eye with the worse visual field MD was considered the worse eye. Asymmetric PACG was defined as the inter‐eye visual field MD difference of greater than 5 dB; and symmetrical PACG disease as an inter‐eye difference of less than 5 dB. Subjects with previous acute primary angle closure were excluded.Results: Based on the definitions, a total of 160 out of 281 PACG subjects (56.9%) presented with asymmetrical disease and 121 (43.1%) with symmetrical disease. Subjects with asymmetric disease had a significantly thinner CCT in the worse eye (529.2 ± 35.2 μm) compared to the fellow eye (535.3 ± 37.2 μm) (p &lt; 0.001), and higher presenting IOP (28.8 ± 12.0 vs 20.1 ± 8.4 mmHg, p &lt; 0.001), but no inter‐eye differences were observed for measurements of AL (p = 0.71) and ACD (p = 0.51) respectively. For patients with symmetric disease, no significant inter‐eye differences were observed for CCT (531.7 ± 31.2 vs 532.9 ± 32.4 μm, p = 0.38), AL (p = 0.30) and ACD (p = 0.31), but the worse eye had significantly higher IOP (22.7 ± 7.9 vs 20.6 ± 6.9 mmHg, p &lt; 0.001). In the asymmetric disease group, 30.6% of subjects had a thinner CCT (≥ 10 μm) in the worse eye compared to 16% of subjects in the symmetric group. There was no correlation between inter‐eye CCT difference and inter‐eye difference of visual field MD (p = 0.17).Conclusions: In PACG subjects with asymmetric disease at presentation, eyes with more severe disease have a thinner CCT and higher presenting IOP. Whether CCT is an independent risk factor for PACG through mechanisms beyond its influence on IOP measurements remains to be established.

Exploratory analysis of choriocapillaris vasculature as a biomarker of idiopathic epiretinal membrane.

To investigate the preoperative choriocapillaris perfusion (CCP) as a biomarker in patients with idiopathic epiretinal membrane (iERM). 28 patients (28 eyes) with unilateral iERM who received pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling were included for retrospective observational study. Optical coherence tomography (OCT) and angiography (OCTA) was performed before and after PPV. Area, perimeter, and circularity of superficial foveal avascular zone (FAZ) were analyzed preoperatively in both eyes using OCTA. Preoperative CCP was also analyzed with binarized en-face OCTA images. Measurements of best-corrected visual acuity (BCVA) and central foveal thickness (CFT) by OCT were conducted at the baseline and 6 months following the surgery. The correlations of preoperative OCT parameters with postoperative BCVA and CFT reduction were analyzed. CCP was significantly lower (p < 0.001) and FAZ had shrunk (p < 0.001) in eyes with iERM compared to unaffected fellow eyes before surgery. BCVA and CFT became significantly improved after surgery (p = 0.001, p < 0.001). Multiple regression analysis revealed that preoperative CCP was significantly related with BCVA improvement (β = 0.185, p = 0.005), postoperative BCVA (β = 0.108, p = 0.023) and ratio of post- to preoperative CFT (β = 0.106, p = 0.044). Preoperative CCP is a biomarker for poor functional and anatomical prognosis after surgery in iERM.

Optical coherence tomography angiography of the foveal avascular zone after successful macula‐off rhegmatogenous retinal detachment repair

Aims/Purpose: To investigate the size and shape of the foveal avascular zone (FAZ) after successful macula‐off rhegmatogenous retinal detachment (RRD) repair using swept source OCT angiography (SS OCTA).Methods: A prospective comparative cross‐sectional study including 21 eyes of 21 patients with macula‐off RRD that were successfully repaired. The size of the superficial FAZ was assessed by its area, length of perimeter, and Feret's diameter, and the shape by the circularity, axial ratio, roundness and solidity. The correlations between each parameter and the clinical and OCT findings were statistically determined. The unaffected fellow eyes were used as controls.Results: The mean initial BCVA was 1.92 ± 0.41 Log MAR (20/2000 Snellen's equivalent). The mean BCVA at OCTA acquisition (3 months) was 0.78 ± 0.39 Log MAR (20/100 Snellen's equivalent) (p &lt; 0.001). FAZ was significantly larger (323.09 ± 129.03 μm2 vs. 245.27 ± 93.15 μm2; p = 0.038), with longer perimeter (2.31 ± 0.35 mm vs. 2.07 ± 0.31 mm; p = 0.048), and irregular shaped (mean circularity: 0.73 ± 0.72 vs. 0.78 ± 0.5; p = 0.019 and mean solidity: 0.90 ± 0.02 vs. 0.93 ± 0.02; p = 0.002) in operated eyes than in the control group. The average Feret's diameter was 0.77 ± 0.10 mm versus 0.71 ± 0.88 mm (p = 0.076). The average axial ratio was 1.25 ± 0.20 versus 1.22 ± 0.22 (p = 0.531), and the average roundness was 0.81 ± 0.11 versus 0.83 ± 0.11 (p = 0.531). Mean central foveal thickness (CFT) was significantly lower in operated eyes than in control eyes (178.23 ± 40.59 μm vs. 247.44 ± 38.2 μm (p &lt; 0.001)). There was a significant inverse correlation between FAZ area and post‐operative outer nuclear layer thickness (r = −0.520, p = 0.016) and CFT (r = −0.571, p = 0.007) in operated eyes. There was no significant correlation between the post‐operative visual acuity and FAZ parameters.Conclusions: Enlargement and irregularities of FAZ after successful macula‐off RRD repair, as demonstrated by SS OCTA, might suggest an ischaemic macular damage caused by RRD that may affect post‐operative functional outcome.

Analysis of Scheimpflug Tomography Parameters for Detecting Subclinical Keratoconus in the Fellow Eyes of Patients with Unilateral Keratoconus in the Eastern Province of Saudi Arabia.

We compared the characteristics of subtle morphological changes in subclinical keratoconus (KC) and normal corneas using Scheimpflug tomography (Pentacam®) and assessed the efficacy of these parameters for distinguishing KC or subclinical KC from normal eyes. In this multicenter comparative study at Dhahran Eye Specialist Hospital and Al Kahhal Medical Complex in the Eastern Province of Saudi Arabia, we analyzed the Scheimpflug tomography charts of patients with topographically normal eyes and those with unilateral KC. Patients were divided into the normal (NL: patients considered for refractive surgery and with normal topographic/tomographic features, 129 eyes), KC (30 patients with manifest KC in one eye based on biomicroscopy and topographical findings), and forme fruste KC (FFKC: fellow eyes of patients in the KC group that met the NL group criteria) groups. Corneal morphological parameters were analyzed using the area under the receiver operating characteristic (ROC) curves (AUCs). For distinguishing NL and KC groups, all measured corneal morphological parameters, except for flat keratometry, maximum Ambrósio relational thickness index, and minimum sagittal curvature, had AUCs >0.75. The surface variance index yielded the largest AUC (0.999). For distinguishing NL and FFKC groups, all corneal morphological parameters had AUCs <0.8. Total higher-order aberrations (RMS HOA) yielded the highest AUC, followed by Belin/Ambrỏsio Enhanced Ectasia total deviation (BAD-D), back elevation at the thinnest location, average pachymetric progression index (PPIave), and deviation of Ambrỏsio relational thickness (Da) (AUC 0.74-0.78). The diagnostic performance of all tested topographic and tomographic parameters measured using Scheimpflug tomography for discriminating subclinical KC was fair at best, with the top parameters being RMS HOA, BAD-D, back elevation at the thinnest location, PPIave, and Da. Distinguishing between subclinical KC and healthy eyes remains challenging. Multimodal imaging techniques may be required for optimal early detection of subtle morphological changes.

Longitudinal changes in peri-papillary retinal nerve fiber layer thickness in patients with unilateral branch retinal vein occlusion.

Associations between retinal venous occlusion (RVO), elevated intraocular pressure, and glaucoma have been reported. Further investigations into structural alterations in the fellow eyes of individuals with unilateral RVO have revealed that the peripapillary retinal nerve fiber layer is thinner than in healthy eyes, suggesting that there may be systemic risk factors common to both RVO and glaucoma. We aimed to evaluate changes in peripapillary retinal nerve fiber layer thickness (pRNFLT) among individuals with unilateral branch retinal vein occlusion (BRVO). This prospective observational study recruited 30 individuals (60 eyes) with newly diagnosed unilateral BRVO and macular edema, and a control group of 30 healthy individuals (30 eyes) with no abnormalities on fundus examination or concurrent systemic comorbidities. After baseline measurements, the participants were reassessed at 6, 12, and 24 months by measuring global and sectoral pRNFLT using spectral-domain optical coherence tomography. The mean age and sex distributions were comparable between the patient and control groups (both P > 0.05). When compared to fellow eyes, global and sectoral pRNFLT in eyes with BRVO were significantly higher at baseline (all P < 0.05). Over time, pRNFLT decreased dramatically, and by the conclusion of the two-year follow-up, there was a significant reduction from baseline in the affected eyes (all P < 0.05). Likewise, affected eyes experienced a significant improvement in best-corrected distance visual acuity and central macular thickness over the two-year follow-up (both P ≤ 0.001). Comparing the global and all-sector pRNFLT of fellow eyes in the patient group with those of normal eyes in the control group, there were no significant differences at any visit, except in the temporal sector, which revealed a significant reduction in pRNFLT at 24 months in the fellow eyes of patients with unilateral BRVO (P = 0.02). Patients with unilateral BRVO experienced a significant reduction in pRNFLT in the affected eyes and, to a lesser extent, in the fellow eyes, compared with that of the control arm, suggesting that they are prone to retinal nerve fiber layer damage. The reduction in pRNFLT in the normal fellow eyes of patients with BRVO may be attributed to age or concurrent systemic comorbidities. Further studies with long follow-up periods are required to shed light on the etiology of functional and structural changes in both the retinal nerve fiber layer and ganglion cell complex in the normal and affected eyes of patients with unilateral BRVO.

Role of Psychological Stress and Choroidal Thickness in Central Serous Chorioretinopathy.

Central serous chorioretinopathy (CSCR) is a disease with a multifactorial aetiology. To evaluate the role of psychological stress and choroidal thickness in patients with CSCR. This was a hospital-based, analytical cross-sectional study, conducted at Christian Medical College, Vellore, India, from 2018 February to 2019 September, after the approval of the Institutional Review Board and Ethics Committee. Patients who satisfied the eligibility criteria of the study, were selected from the outpatient clinics of the Department of Ophthalmology. Twenty-five patients with unilateral CSCR (Group 1 - cases), and 50 age and gender-matched patients without CSCR (Group 2 - controls), randomly selected in a 1:2 ratio, were enrolled after obtaining informed consent. Psychological stress was assessed using Cohen Perceived Stress Scale (PSS-10). All patients had a Swept Source optical coherence tomography scan of the macula. Subfoveal choroidal thickness (SFCT) of both eyes of all participants was measured using a standard protocol. The data were collated and analysed, using Independent samples t-test and Chi-square/ Fisher's exact test, as appropriate, with IBM SPSS Statistics for Windows, version 21 (IBM Corp., Armonk, N.Y., USA). There was a significant difference between the two groups in mean stress scores (p <0.01), as well as stress categories (p <0.01). Although there was no significant difference in the prevalence of hypertension between the two groups (p = 0.33), there was a significant difference both in the mean systolic (p <0.01) and diastolic (p <0.01) blood pressure between the two groups. We found a significant difference between mean SFCT of CSCR eyes (421+/- 78.34 μm) and control eyes (314.24 +/- 52.48 μm, p <0.01), as well as between fellow eyes (396.20 +/- 68.79 μm) and control eyes (314.24 +/- 52.48 μm, p <0.01). However, there was no significant difference in the mean SFCT of CSCR eyes and fellow eyes (p =0.24). The findings reiterate the concept that the underlying pathophysiological changes leading to CSCR involve both the eyes of the patient. Psychological stress and hypertension may be factors that play an important role in the etiopathogenesis of the pachychoroid-related changes leading to CSCR. Stress relief measures, with a holistic approach to management, should be an integral part of the therapeutic strategies for CSCR.

Myopia progression in school children with prolonged screen time during the coronavirus disease confinement.

Myopia, the most common refractive error, is a global public health problem with substantial visual impairment if left untreated. Several studies have investigated the association between increased near-work and restricted outdoor activities in children with myopia; however, such studies in children without myopia are scarce. We aimed to monitor the effect of the coronavirus disease-2019 (COVID-19) home confinement and mandatory virtual learning on myopic progression among myopic and non-myopic school-aged children. We conducted a retrospective chart review of children aged 6 - 12 years attending regular visits to the pediatric ophthalmology clinic in a tertiary eye hospital in Eastern Province, Saudi Arabia. Cycloplegic refraction was determined from three visits at least six months apart: two visits before the start of the COVID-19 pandemic and one during the COVID-19 home confinement. Parents were asked about the time spent in near-work and outdoor activities, the devices used during virtual learning, and the demographic characteristics of the children. Statistical analyses were conducted to compare myopia progression before and during the COVID-19 home confinement. A total of 160 eyes of 80 children were analyzed. The boy (n = 46) to girl (n = 34) ratio was 1.4:1. The hyperopia (n = 131 eyes) to myopia (n = 29 eyes) ratio was 4.5:1. Most eyes exhibited a hyperopic shift before the confinement; however, all eyes displayed a myopic shift during the confinement. When comparing both eyes of the same individual, the more myopic or less hyperopic eye in the same child had a significantly greater myopic shift than the fellow eye (both P < 0.05). Children who used tablets showed a significant myopic shift (P < 0.05). Likewise, children in both age categories ( ≤ 8 and > 8 years), boys, those living in an apartment, and those having parents with bachelor's degrees experienced a significant myopic shift during COVID-19 home confinement compared to before (all P < 0.05). The mean myopic shift was greater in children aged > 8 years than in those aged ≤ 8 years. Children with and without a family history of myopia had a myopic shift in the mean spherical equivalent during COVID-19 home confinement; however, that of children with no family history was statistically significant (P < 0.05). Progression of myopia accelerated in children during the COVID-19 pandemic. Excessive time spent on digital screen devices at near distances is considered a substantial environmental contributor to myopic shift in children. Further multicenter studies with extended follow-up periods are needed to assess the factors contributing to myopic progression in our population.

Visual outcome measures in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD)

BackgroundMyelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) comprises various age-dependent clinical phenotypes and may be monophasic, multiphasic, or chronic. Optic neuritis (ON) is a common manifestation and frequently appears in combination with other MOGAD phenotypes, particularly in young children. Despite permanent structural damage to the retinal nerve fiber layer (RNFL), children often experience complete visual recovery. AimsTo analyze the progression and impact of MOGAD on the visual system of pediatric patients independently of the history of ON. MethodsThis retrospective study included children who met specific criteria: myelin oligodendrocyte glycoprotein (MOG) immunoglobulin G (IgG) seropositivity, acute presentation of MOGAD, and written general consent. Main outcome measures were global peripapillary retinal nerve fiber layer (pRNFL) thickness, and near and distance visual acuity, analyzed using descriptive statistics. ResultsWe identified 10 patients with median age of 7.7 years at first event: 7 patients manifested with acute disseminated encephalomyelitis (ADEM) (with ON 5/7, ADEM only 1/7, with transverse myelitis (TM) 1/7), 2 with isolated ON, and 1 patient with neuromyelitis optica spectrum disorder (NMOSD)-like phenotype with ON. Among ON patients, 5/8 were affected bilaterally, with 3 initially diagnosed with unilateral ON but experiencing subsequent involvement of the fellow eye. None of the patients without previous ON showed a deterioration of visual acuity and, if evaluated, a reduction of the pRNFL. ConclusionMost pediatric MOGAD-ON patients in our cohort presented with acute vison loss and optic disc edema. All patients achieved complete visual recovery, independent of number of relapses or initial visual loss. The pRNFL thickness decreased for several months and stabilized at reduced levels after 12 months in the absence of further relapses. MOGAD may not have subclinical/’silent’ effects on the visual system, as visual acuity and pRNFL were not affected in patients without ON.

Влияние осевой миопии на течение неоваскулярной формы возрастной макулярной дегенерации на фоне анти-VEGF-терапии

Purpose. To determine the effect of increased axial length of the eyes on the course of choroidal neovascularization (CNV) in patients with neovascular age-related macular degeneration (AMD) during anti-VEGF therapy. Material and methods. The study included 29 people (34 eyes) with neovascular AMD occurring against the background of axial myopia, in comparison with control eyes. The length of the anterior-posterior axis (APA) was 25.42 (24.25; 27.55) mm. The influence of axial myopia on degenerative changes in the fundus such as myopic maculopathy and posterior staphyloma (PS) was analyzed. The type of CNV, parameters of the neovascular complex and retina, retinal microcirculation in the foveal area before treatment and at the end of the observation period, and correlations were assessed using optical coherence tomography (OCT) and OCT angiography (OCTA). Treatment was with intravitreal anti-VEGF. The follow-up period was 28.80 (15.18; 44.10) months. The number of intravitreal injections (IVI) was 7.75 (5.70; 9.85). Results. «Mild» categories of myopic maculopathy were detected by ophthalmoscopy – mosaic fundus (K1) in 20.60% and diffuse chorioretinal atrophy (K2) in 17.60% of cases. PS in eyes with CNV and fellow eyes was detected in 17.50 and 21.00% of eyes, respectively, types were identified exclusively without involvement of the macular area. CNV types 1 and 2 were detected in equal proportions – in 43.48 and 56.52% of eyes, respectively. Visual functions and OCT parameters of the retina and CNV reached the maximum positive values after 2 loading injections of anti-VEGF. A significant positive dynamics of retinal microcirculation in the foveal zone was established by the end of the observation period against the background of a decrease in exudative changes in the retina. Correlation analysis showed a direct relationship between the number of injections and the extent of CNV before treatment (rφ=0.743; p=0.009) and the height of the neuroepithelium above the CNV before treatment (r φ=0.378; p=0.027). Conclusion. The presence of axial myopia in patients with neovascular AMD contributes to the appearance of minimal degenerative changes in the posterior pole of the eyes, which has a positive effect on visual function and CNV during antiVEGF therapy. Key words: choroidal neovascularization, neovascular age-related macular degeneration, axial myopia, optical coherence tomography angiography, anti-VEGF therapy

Tear lactoferrin concentration in patients with recurrent herpetic stromal keratitis and therapeutic effect of Lacto eyedrops in the multicomponent treatment for this disorder

Background: Herpetic stromal keratitis (HSK) is an immunomodulatory disease that develops as a result of herpes simplex virus (HSV)1 or HSV2 reactivation. HSK is the most common form (20-50%) of recurrent herpetic keratitis (HK) that most commonly results in significantly reduced vision. It is well known that changes in biological compound levels in tear fluid can be indicative of the state of the ocular surface and determine whether ocular surface pathology is present, and, therefore, can be used as diagnostic markers of pathological changes in the ocular surface. Lactoferrin (LF) is one of these compounds and has been proven to have innate antibacterial, antifungal, antiviral, antiparasite, anti-inflammatory, immunomodulatory, antioxidative and other properties. Purpose: To determine tear Lf concentration in patients with recurrent acute HSK, its effect on functional characteristics of the ocular surface, and the therapeutic effect of Lacto eyedrops in the comprehensive treatment for this disorder. Material and Methods: The study was conducted at the site of Corneal Pathology Department and Immunology Laboratory of the Institute in January to December 2021. Seventeen patients (17 affected eyes and 17 fellow eyes) with recurrent acute HSK were included in the study. Mean patient age plus or minus standard deviation (SD) was 48.7 ± 16.0 years. The ophthalmological examination included biomicroscopy of the bulbar conjunctiva and cornea, fluorescein test, determination of corneal sensation and basal tear production (Schirmer’s II test), and microbiological examination of the conjunctiva. Tear Lf concentration was determined by a human Lf enzyme-linked immunosorbent assay (ELISA) kit (Elabscience Biotechnology, Inc., Wuhan, China). The results were photometrically measured at 450 nm with an ELISA reader (Stat Fax 2100, Awareness Technology Inc, Palm City, FL). Lacto eyedrops were administered two times a day for 30 days. Tear Lf concentrations were determined at baseline and at day 30. Results: Mean tear LF concentration plus or minus SD in eyes of patients with recurrent HSK was 1.21 ± 0.52 g/l, with no significant difference between the affected eye and fellow eye. However, a subnormal tear LF concentration was more common in the affected eye than in the fellow eye (2 = 4.24, р = 0.04). After a 30-day anti-inflammatory treatment with Lacto eyedrops, mean tear LF concentration plus or minus SD increased by 47% to 1.78 ± 0.7 g/l in the affected eyes. A corneal sensation score of 1 to 9 was 12.4 times more common in HSK eyes than in fellow eyes (OR = 12.4; 95% CI, 2.0–76.8), which reflects neurosensory abnormalities in the affected eye. Corneal sensation loss, was, however, more common in HSK eyes with a low tear Lf concentration than in fellow eyes with a low tear Lf concentration. Median basal tear production (as assessed by Schirmer’s II test) was as low as 7-8 mm in eyes with a low tear Lf concentration and as high as 13-16 mm in eyes with a high tear Lf concentration (p less 0.05). There was a direct correlation between the basal tear production and the tear Lf concentration (r=0.45; p less 0.05). Among study patients with recurrent HSK, 24.9% showed baseline microbiological evidence of potentially pathogenic or fungal organisms in the conjunctiva. A course of multicomponent anti-inflammatory treatment with Lacto eyedrops contributed to complete removal of these organisms. Conclusion: We determined mean tear Lf concentrations in affected and fellow eyes of patients with recurrent HSK, and established certain relationships between functional characteristics of the ocular surface and tear Lf concentrations in these eyes. A disinfecting effect of Lacto eyedrops against any microorganisms present in the conjunctival sac of patients with recurrent HSK was confirmed by the absence of culture growth on completion of the multicomponent anti-inflammatory treatment.

Optimizing the algorithm for assessing the efficacy of treatment for amblyopia in astigmats through the investigation of the features of meridional acuity characteristics as vector quantities

Background: Refractive asymmetry associated with astigmatism may cause a special form of amblyopia, meridional amblyopia (MA). MA manifests itself as alterations in selective mechanisms of visual stimulus processing during recognition of contours of a certain orientation. Current routine examination of amblyopes does not include meridional acuity assessment and thus does not allow determining whether MA is present or not, as well as performing a more detailed evaluation of the efficacy of treatment for amblyopia in astigmats. Purpose: To optimize the algorithm for assessing the efficacy of stand-alone and complex methods of treatment for amblyopia in astigmats through the determination of the features of changes in visual acuities in orthogonal retinal meridians as vector quantities. Material and Methods: Twenty-four hyperopic astigmats with amblyopia (48 eyes) aged 5 to 12 years were involved in the study. Patients were treated by accommodative facility training only and, in 3 months, by complex therapy (accommodative facility training plus the use of device-based methods). Treatment course duration was 10 days. The results were assessed by changes in best-corrected visual acuity (Sivtsev Chart) and meridional separable visual acuity (MSVA) determined with the software which generates Landolt ring optotypes. Results: The study sample was found to be heterogeneous regarding the features of asymmetries in MSVA. Separable visual acuity in the horizontal meridian was equal in magnitude to that in the vertical meridian in 16.65% of patients. Asymmetries in separable visual acuity that may be considered MA were found in dominant and non-dominant (fellow) eyes in 83.35% of astigmats with amblyopia. Two different clusters were determined in the group with asymmetries in MSVA. Separable visual acuity in the horizontal meridian was higher than that in the vertical meridian in 35.45% of eyes in cluster 1, and lower than that in the vertical meridian in 47.85% of eyes in cluster 2. After treatment, mean separable visual acuity value in the vertical meridian was practically similar to that in the horizontal meridian in both groups for the dominant and fellow eyes, which allowed concluding that both methods were equally effective in treating the disease. However, the number of eyes with the same MSVA in orthogonal meridians increased by 10.41% after MA treatment with accommodative facility training only versus 18.75% after complex treatment. Conclusion: Assessing the features of changes in visual acuities in orthogonal retinal meridians as vector quantities enables obtaining principally new information on the performance of sensory functions in patients with amblyopia and assessing more reliably the efficacy of stand-alone and complex pleoptic methods as methods of treatment for MA.