Intensity-based optoretinography reveals sub-clinical deficits in cone function in retinitis pigmentosa.

Introduction: Clinical tools have been widely used in the diagnosis, description, and monitoring the progression of retinitis pigmentosa (RP); however, many of these methods have inherently low sensitivity and specificity, and significant photoreceptor disruption can occur before RP progression has clinically manifest. Adaptive optics scanning light ophthalmoscopy (AOSLO) has shown promise as a powerful tool for assessing photoreceptor disruption both structurally and functionally due to its increased resolution. Methods: Here we assess photoreceptor structure and function at the cellular level through AOSLO by acquiring intensity based optoretinography (iORG) in 15 individuals with no reported retinal pathology and 7 individuals with a prior clinical diagnosis of RP. Photoreceptor structure was quantified by calculating cone nearest neighbor distance (NND) across different retinal eccentricities from the AOSLO images. Cone outer segment length was measured across different retinal eccentricities using optical coherence tomography (OCT) derived longitudinal reflectivity profiles (LRPs). Finally, iORG measures of photoreceptor function were compared to retinal sensitivity as measured using the macular integrity assessment (MAIA) microperimeter. Results: Broadly, participants with RP exhibited increasing cone nearest neighbor distances and decreasing cone outer segment length as a function of retinal eccentricity, consistent with prior reports for both controls and individuals with RP. Nearly all individuals with RP had reduced iORG amplitudes for all retinal eccentricities when compared to the control cohort, and the reduction was greater in eccentricities further from the fovea. Comparing iORG amplitudes to MAIA retinal sensitivity, we found that the iORG was more sensitive to early changes in photoreceptor function whereas MAIA was more sensitive to later stages of disease. Discussion: This highlights the utility of iORG as a method to detect sub-clinical deficits in cone function in all stages of disease progression and supports the future use of iORG for identifying cells that are candidates for cellular based therapies.

Outer retina and choroid as potential imaging markers for evaluation of neural impairment in early type 2 diabetic patients.

PURPOSE: To quantify the presence of early structural alterations in the outer retinal layer and choroid among healthy subjects and diabetic patients with no or mild diabetic retinopathy, and to establish the correlation between the measured structural parameters and retinal sensitivity. METHODS: In total, 31 eyes from subjects with type 2 diabetes and 29 eyes from healthy subjects were enrolled. Optical coherence tomography was used to measure outer retina layers and choroid, while microperimetry was used to characterize the changes of visual function in a 6-mm diameter area at macula. Quantitative analysis of structural and functional changes was performed between groups and the structure-function correlations were determined. RESULTS: The thickness of myoid and ellipsoid zone, choroid and the mean retinal sensitivity were significantly smaller in diabetic group than that in controls (all P values < 0.05). Besides, thinner choroid and outer retina was associated with the decreased retinal sensitivity，especially in diabetic patients (r = 0.377, P = 0.048; r = 0.401, P = 0.034; respectively). Final multiple regression models showed the outer retinal thickness (ORT) (P = 0.033), choroidal thickness (P = 0.003) and the interaction between ORT and choroidal thickness (P = 0.001) were significant predictors to retinal sensitivity. CONCLUSIONS: Thinning of choroid and outer retina were significantly correlated with reduced retinal sensitivity, which indicate outer retina and choroid might be potential imaging markers for evaluation of visual function related to neural impairment in type 2 diabetic patients without or in the early stage of diabetic retinopathy.

Genetic Linkage between CAPN5 and TYR Variants in the Context of Albinism and Autosomal Dominant Neovascular Inflammatory Vitreoretinopathy Absence: A Case Report.

We present a case involving a patient whose clinical phenotype aligns with oculocutaneous albinism (OCA), yet exhibits a complex genotype primarily characterized by variants of unknown significance (VUS). An 11-year-old boy manifested iris hypopigmentation and translucency, pronounced photophobia, diminished visual acuity and stereopsis, nystagmus, reduced pigmentation of the retina, and foveal hypoplasia. Genetic testing was performed. A heterozygous missense VUS CAPN5 c.230A>G, p.(Gln77Arg), a heterozygous missense VUS TYR c.1307G>C, p.(Gly436Ala), and a heterozygous missense variant TYR c.1205G>A, p.(Arg402Gln) which was classified as a risk factor, were identified. We hypothesized that the TYR c.1307G>C, p.(Gly436Ala) variant is in genetic disequilibrium with the TYR c.1205G>A, p.(Arg402Gln) variant leading to deficient expression of melanogenic enzymes in retinal cells, resulting in the manifestation of mild OCA. Additionally, this study represents the case where we did not detect chiasmal misrouting in visual evoked potentials, nor did we observe a shift in the distribution of ganglion cell thickness from a temporal to a central position. Moreover, our patient's case supports the probable benign nature of the CAPN5 c.230A>G, p.(Gln77Arg) variant.

Evaluation of macular integrity, after retinal detachment surgery, using MAIA microperimetry.

BACKGROUND AND OBJECTIVE: To describe visual function, macular integrity, and fixation stability using MAIA microperimetry (macular integrity assessment) after retinal detachment surgery. Evaluate if there are statistically significant differences between surgical approaches. MATERIALS AND METHODS: A prospective, comparative, interventional study was conducted, recruiting a total of 21 patients with rhegmatogenous retinal detachment and macula-off. Eleven patients underwent surgery using pars plana vitrectomy (PPV), and 10 patients underwent scleral buckle surgery. Clinical examinations and optical coherence tomography (OCT) were performed post-surgery. MAIA microperimetry was conducted at 6 months. RESULTS: Best-corrected visual acuity (BCVA) and the number of letters read improved over time in the operated eye but did not reach the level of the control eye (p = 0.001). No significant differences were found between the two surgical approaches in BCVA (p = 0.230) or the number of letters read (p = 0.608). Macular integrity in the operated eye did not match that of the control eye in both procedures (p = 0.05). No differences were detected between the two surgeries, either in macular integrity (p = 0.512) or fixation stability (p = 0.835). CONCLUSIONS: Following retinal detachment surgery, a decrease in BCVA and the number of letters read occurs, which does not reach the level of the control eye. No significant differences were observed between the two surgical approaches. Macular integrity in the operated eye does not match that of the control eye.

Retinal characteristics of female choroideremia carriers: Multimodal imaging, microperimetry and genetics.

PURPOSE: Describe visual function and retinal features of female carriers of choroideremia (CHM), using multimodal imaging and microperimetry. DESIGN: Cross-sectional cohort study PARTICIPANTS AND CONTROLS: CHM carriers seen in Australia (Melbourne or Perth) or United Kingdom (Oxford or Cambridge) between 2012 and 2023. Healthy age-matched controls seen in Melbourne, Australia, between 2022 and 2023. METHODS: Participants had visual acuity, fundus-tracked microperimetry, optical coherence tomography (OCT), and fundus autofluorescence (FAF) imaging performed. CHM carriers were either genetically and/or clinically confirmed (i.e., obligate carriers). CHM carriers were grouped according to their retinal phenotype and compared to healthy controls. Statistical analyses were performed on StataBE (v18.0). MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA), low-luminance visual acuity (LLVA), average retinal sensitivity, volume of macular hill of vision (HoV), inner retinal thickness (IRT), and photoreceptor complex (PRC) thickness. RESULTS: Eighty-six eyes of 43 CHM carriers and 60 eyes of 30 healthy controls were examined using multimodal imaging and microperimetry. Median age was 54 and 48.5 years for CHM carriers and controls, respectively (p=0.18). Most CHM carriers (86%) were genetically confirmed. CHM carriers and controls had strong inter-eye correlation between eyes for BCVA and average retinal sensitivity (p<0.001). LLVA and macular HoV tests were sensitive tests to detect changes in CHM carriers with mild phenotypes (i.e., fine and coarse). CHM carriers with geographic and/or male pattern phenotypes had reduced BCVA, LLVA, retinal sensitivity, and retinal thinning, compared to healthy controls. Retinal thickening of the inner retina was observed in the central 1 degree, despite generalised thinning of the PRC in the central 7 degrees, indicating retinal remodelling in CHM carriers, compared to controls. There were no genotype-phenotype correlations observed. CONCLUSIONS: Female carriers of CHM with severe retinal phenotypes (i.e., geographic or male pattern) have significantly decreased visual function and retinal structural changes, when compared to age-matched controls and those carriers with milder phenotypes. LLVA and volumetric measures of the macular HoV were found to be the most sensitive functional tests to detect milder retinal disease (fine and coarse phenotypes) in CHM carriers.

Structural and functional characterization of retinal impairment in T1DM patients without diabetic retinopathy: a 3-year longitudinal study.

PURPOSE: To analyze the progression of structural and functional retinal impairment in type 1 diabetes mellitus (T1DM) patients with no clinical signs of diabetic retinopathy (DR) during a 3-year follow-up. METHODS: This was an observational longitudinal study. Post-pediatric T1DM patients without clinical signs of DR, and sex- and age-matched healthy subjects were recruited at San Raffaele Hospital (Milan, Italy). Each patient underwent a comprehensive ophthalmological evaluation, including optical coherence tomography (OCT), OCT-angiography (OCT-A), retinal static and dynamic vessel analysis (DVA), and microperimetry. RESULTS: 21 eyes of 21 T1DM patients (10 females; 24 ± 2 years old), and 21 age and sex-matched healthy subjects were enrolled. At baseline, T1DM eyes revealed a significantly decreased vessel length density using OCT-A (p < 0.001 and p = 0.046 in 3 × 3 and 6 × 6 mm images) and a significantly increased vessel density index (p = 0.013 and p = 0.087 in 3 × 3 and 6 × 6 mm images) of deep capillary plexus. DVA detected a significantly decreased vessel response to flicker light (p = 0.002). A significantly increased thickness of ganglion cellular layer 6-mm-diameter subfields in inferior and superior quadrants was found in diabetic patients (p < 0.001 in both subfields). At 3-years-follow-up no significant longitudinal changes were disclosed in all analyses. CONCLUSIONS: Concomitant subclinical microvascular and neurodegenerative damages could be early signs of DR onset that precede functional alterations and clinical signs of DR development. These alterations demonstrated a stable trend over time.

MP-3 microperimeter in early primary open angle glaucoma with a new pattern.

AIM: To investigate macular microperimetry in patients with early primary open angle glaucoma (POAG) using a new custom-made pattern, and analyze the characteristics of macular sensitivity. METHODS: This case-control study included 38 patients with POAG, who were divided into pre-perimetric glaucoma (18 eyes of 18 patients), early-stage (20 eyes of 20 patients), and control (20 eyes of 20 patients) groups. All subjects underwent standard 24-2 humphrey visual field test. An MP-3 microperimeter with a new custom-made pattern (28 testing points distributed in four quadrants, covering the central 10° of the retina) was used to evaluate macular sensitivity. Ganglion cell complex (GCC) thicknesses were examined using an RS-3000 Advance OCT system. The features of structure and function were analysed per quadrant. RESULTS: The pre-perimetric glaucoma group had significantly lower inferior hemifield macular sensitivity compared to controls (P<0.05). The early-stage POAG group had significantly lower average, inferior hemifield, inferonasal, and inferotemporal mean sensitivities compared to the pre-perimetric glaucoma group (P<0.05), and lower macular sensitivity in all sectors compared to controls (P<0.05). Regarding GCC thickness, all sectors in the early-stage POAG group became thinner compared to those in controls (P<0.05); whereas all sectors in the early-stage POAG group, except the superonasal quadrant, became thinner compared to those in the pre-perimetric glaucoma group (P<0.05). Macular sensitivity and GCC thickness were significantly associated in each sector. The inferotemporal quadrant had the highest correlation coefficients (0.840). The structure-function relationship for the inferonasal and inferotemporal sectors was stronger compared to the corresponding superior sectors. CONCLUSION: Microperimetry reveals variations in macular sensitivity in patients with early glaucoma earlier than conventional perimetry, particularly in pre-perimetric glaucoma cases in which it might be undetectable by conventional methods. The new custom-made pattern may improve the accuracy of microperimetry by enhancing point arrangement and reducing fatigue effects. Macular sensitivity measured by MP-3 with this pattern shows statistically significant structural and functional associations with the thicknesses of the GCC.

[Multimodal topographically oriented approach to the study of full-thickness macular holes]. / Mul'timodal'nyi topograficheski orientirovannyi podkhod k izucheniyu skvoznykh makulyarnykh razryvov.

PURPOSE: This article studies the relationship between structural changes according to the findings of optical coherence tomography (OCT) and OCT angiography (OCTA), microperimetry (MP), multifocal electroretinography (mfERG) parameters in topographically corresponding areas of the macular region in idiopathic full-thickness macular holes (FTMH). MATERIAL AND METHODS: OCT, OCTA, MP and mfERG were performed in 14 eyes with FTMH stages I-IV according to Gass. In 13 points at a distance of 0-2.5°, 2.5-5.0°, and 5.0-10.0° from the fixation point, the light sensitivity (LS), amplitude and latency of the P1 component were compared with the size of the hole, the area of cystic changes (CC) at the level of the inner nuclear layer (INL) and the outer plexiform layer and Henle fiber layer complex (OPL+HFL), vessel density in the superficial and deep capillary plexus (SCP and DCP). RESULTS: LS and P1 component amplitude were significantly reduced at a distance of up to 5.0° from the fixation point. LS correlates with the apical and basal diameter of the hole (R> -0.53), the area of CC in the INL (R> -0.62) and the OPL+HFL complex (R> -0.55), the density of vessels in the SCP at a distance of up to 2.5° from the fixation point (R>0.51) and in the DCP at a distance of up to 5° from the fixation point (R>0.49). The P1 amplitude correlates with the basal diameter of the hole (R= -0.38), the area of CC in the INL and the OPL+HFL complex (R> -0.33) and vessel density in the SCP (R=0.37) at a distance of up to 2.5° from the fixation point, as well as vessel density in the DCP at a distance of up to 5° from the fixation point (R=0.47). Vessel density in the DCP is significantly lower in the presence of CC in the retina (p<0.001). CONCLUSION: In FTMH, there is a relationship between bioelectrical activity and LS, and structural disorders, capillary perfusion in different layers of the retina. A multimodal topographically oriented approach allows studying the relationship between structural and functional parameters in individual points of the retina and can be used in monitoring of FTMH after surgical treatment.

[Wavefront characteristics in amblyopia of different etiologies in children]. / Osobennosti volnovogo fronta pri ambliopii razlichnogo geneza u detei.

Purpose. The study investigates corneal and higher-order internal aberrations in patients with amblyopia of different etiologies and their relationship with visual acuity, refraction, axial length, and fixation parameters. MATERIAL AND METHODS: Forty-five patients (90 eyes) were examined. All patients were divided into five groups: 1 - with dysbinocular amblyopia; 2 - with refractive amblyopia; 3 - with anisometropic amblyopia; 4 - with relative amblyopia due to congenital myopia; 5 (control) - fellow eyes without amblyopia. Aberrometry was performed using the OPD-Scan III device (Nidek, Japan). Fixation parameters were studied on the MP-3 microperimeter (Nidek, Japan). Correlation analysis was performed using Pearson's linear correlation coefficient (r). RESULTS: In amblyopia associated with congenital myopia, a significant increase in corneal and internal aberrations RMS, Total HOA, astigmatism (V) (0.65±0.26; 1.01±0.31; 4.22±1.17; -2.17±0.72; 0.86±0.3, respectively; control group - 0.44±0.19; 0.58±0.27; 1.0±0.75; -0.94±0.89; 0.47±0.65) and internal spherical aberration (0.06±0.02; control group - 0.04±0.03) was found. In dysbinocular amblyopia, a significant increase in internal aberrations Trefoil (V) and Coma (H) (0.75±0.52 and 0.17±0.35, respectively; control group - 0.05±0.28 and -0.07±0.21) was found, which correlated with a decrease in fixation density in the 2° ring (r= -0.40, r= -0.41). CONCLUSIONS: The increased level of higher-order aberrations in amblyopia associated with congenital myopia is due to the anatomical and optical features of the eyes. The increase in internal aberrations Trefoil (V) and Coma (H) in dysbinocular amblyopia is associated with a mismatch of the optical elements of the eye due to impaired fixation, i.e., it is not the cause, but the consequence of amblyopia.

The Natural History of Retinal Sensitivity Loss in Diabetic Macular Ischemia over One Year Evaluated by Microperimetry.

Background/Objectives: This one-year prospective observational study, conducted at two centers, aimed to report the natural history of retinal sensitivity (RS) loss in diabetic macular ischemia (DMI). Methods: Patients with stable-treated proliferative diabetic retinopathy (PDR) were recruited if there was evidence of DMI on optical coherence tomography angiography, defined as a foveal avascular zone ≥ 0.5 mm2 or parafoveal capillary dropout ≥ 1 quadrant. The minimal visual acuity required for performing microperimetry (MP) was ≥54 Early Treatment Diabetic Retinopathy Study letters (Snellen equivalent 20/80). The overall RS (oRS) and pointwise sensitivity (PWS) within the 3 × 3 mm macula were assessed at baseline and twelve months. A value <25 decibels (dB) was defined as impaired RS, and a decrease of 2 and 7 dB was regarded as mild and severe loss, respectively. Results: A total of 88 patients (97 eyes) were included. No statistically significant MP changes were detected at one year. However, 10% of the cohort lost oRS ≥ 2 dB, and 73% lost ≥2 dB PWS in ≥5 loci, whereas 1% lost oRS ≥ 7 dB, and 4% lost ≥7 dB PWS in ≥5 loci. The foveola and temporal parafovea were the most vulnerable to severe RS loss. Compared to their counterpart, eyes with baseline oRS ≥ 25 dB had significantly more RS loss in the macula and superior parafovea (55% versus 32% and 53% versus 28%, both p = 0.01). Conclusions: Rather than oRS loss, ≥2 dB loss in PWS in ≥5 loci is a more feasible outcome measure for clinical trials in DMI.

Two-photon vision - Seeing colors in infrared.

This review discusses the current state of knowledge regarding the phenomenon called two-photon vision. It involves the visual perception of pulsed infrared beams in the range of 850-1200 nm as having colors corresponding to one-half of the IR wavelengths. It is caused by two-photon absorption (TPA), which occurs when the visual photopigment interacts simultaneously with two infrared photons. The physical mechanism of TPA is described, and implications about the efficiency of the process are considered. The spectral range of two-photon vision is defined, along with a detailed discussion of the known differences in color perception between normal and two-photon vision. The quadratic dependence of the luminance of two-photon stimuli on the power of the stimulating beam is also explained. Examples of recording two-photon vision in the retinas of mice and monkeys are provided from the literature. Finally, applications of two-photon vision are discussed, particularly two-photon microperimetry, which has been under development for several years; and the potential advantages of two-photon retinal displays are explained.

Severity of Disorganization of Retinal Layers and Visual Function Impairment in Diabetic Retinopathy.

PURPOSE: To evaluate best-corrected visual acuity (BCVA), retina sensitivity (RS), and fixation impairment by microperimetry (MP) due to the presence and severity of disorganization of retinal inner and outer layers (DRIL/DROL) and ischemia in OCT/OCT angiography (OCTA) in diabetic retinopathy (DR). DESIGN: Retrospective case-control study. SUBJECTS: Seventy-six eyes (65 patients) with DR were analyzed. Major exclusion criteria were: center-involving diabetic macular edema (DME), significant media opacity, nondiabetic macular pathology, and active proliferative DR. Patients with DRIL and DROL within central 3 mm were enrolled as cases. Patients with DR and no retina disorganization were considered as controls. METHODS: A detailed grading of MP and OCT/OCTA images using Image J software, and specific Image Manipulation Program was applied to colocalize the presence of retina disorganization and RS. Best-corrected visual acuity and RS were correlated with the disorganization of retina layers' characteristics and grading (grade 1-DRIL; grade 2-DROL; grade 3-DROL plus, with involvement of the ellipsoid zone). The same procedure of colocalization was applied to the vascular layers on OCTA using MATLAB. MAIN OUTCOME MEASURES: Correlation between BCVA and MP parameters with disorganization of retina layers grading and OCTA parameters. RESULTS: Best-corrected visual acuity, mean RS within 1 mm and central 3 mm (overall RS [oRS]), perfusion density, vessel density, and geometric perfusion deficit in intermediate and deep capillary plexuses were lower in cases versus controls (P < 0.001). Mean RS within 1 mm (21.4 decibels [dB] ± 2.4 vs. 13.8 dB ± 5.4, P = 0.002), oRS (22.0 dB ± 2.1 vs. 14.4 dB ± 4.6, P < 0.001), and BCVA (76.1 ± 7.4 vs. 61.2 ± 20.4 ETDRS letters; P = 0.02), had a significant decrease from grade 1 to grade 3 retina disorganization. Choriocapillaris flow voids (CC-FVs) increased from grade 1 to grade 3 (DROL plus) (P = 0.004). Overall retina sensitivity and CC-FV were identified as significant predictors of retina disorganization grade with an adjusted coefficient of determination, R2 = 0.45. Cases had more dense scotomas (P = 0.03) than controls with a positive correlation between the worsening of fixation stability and the severity of DRIL/DROL (P = 0.04). CONCLUSIONS: Microperimetry and BCVA documented a reduction in visual function in patients with DR and disorganization of retina layers at different grades, with greater functional impairment when outer retina layers and photoreceptors are involved. The severity of retina disorganization and the presence of ischemia could serve as a potential biomarker of functional impairment. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Defining the structure-function relationship of specific lesions in early and advanced age-related macular degeneration.

The objective of this study is to define structure-function relationships of pathological lesions related to age-related macular degeneration (AMD) using microperimetry and multimodal retinal imaging. We conducted a cross-sectional study of 87 patients with AMD (30 eyes with early and intermediate AMD and 110 eyes with advanced AMD), compared to 33 normal controls (66 eyes) recruited from a single tertiary center. All participants had enface and cross-sectional optical coherence tomography (Heidelberg HRA-2), OCT angiography, color and infra-red (IR) fundus and microperimetry (MP) (Nidek MP-3) performed. Multimodal images were graded for specific AMD pathological lesions. A custom marking tool was used to demarcate lesion boundaries on corresponding enface IR images, and subsequently superimposed onto MP color fundus photographs with retinal sensitivity points (RSP). The resulting overlay was used to correlate pathological structural changes to zonal functional changes. Mean age of patients with early/intermediate AMD, advanced AMD and controls were 73(SD = 8.2), 70.8(SD = 8), and 65.4(SD = 7.7) years respectively. Mean retinal sensitivity (MRS) of both early/intermediate (23.1 dB; SD = 5.5) and advanced AMD (18.1 dB; SD = 7.8) eyes were significantly worse than controls (27.8 dB, SD = 4.3) (p < 0.01). Advanced AMD eyes had significantly more unstable fixation (70%; SD = 63.6), larger mean fixation area (3.9 mm2; SD = 3.0), and focal fixation point further away from the fovea (0.7 mm; SD = 0.8), than controls (29%; SD = 43.9; 2.6 mm2; SD = 1.9; 0.4 mm; SD = 0.3) (p ≤ 0.01). Notably, 22 fellow eyes of AMD eyes (25.7 dB; SD = 3.0), with no AMD lesions, still had lower MRS than controls (p = 0.04). For specific AMD-related lesions, end-stage changes such as fibrosis (5.5 dB, SD = 5.4 dB) and atrophy (6.2 dB, SD = 7.0 dB) had the lowest MRS; while drusen and pigment epithelial detachment (17.7 dB, SD = 8.0 dB) had the highest MRS. Peri-lesional areas (20.2 dB, SD = 7.6 dB) and surrounding structurally normal areas (22.2 dB, SD = 6.9 dB) of the retina with no AMD lesions still had lower MRS compared to controls (27.8 dB, SD = 4.3 dB) (p < 0.01). Our detailed topographic structure-function correlation identified specific AMD pathological changes associated with a poorer visual function. This can provide an added value to the assessment of visual function to optimize treatment outcomes to existing and potentially future novel therapies.

[The effect of pleoptic treatment on the stability of visual fixation in children and adolescents with amblyopia of various degrees]. / Vliyanie pleopticheskogo lecheniya na stabil'nost' zritel'noi fiksatsii u detei i podrostkov s ambliopiei po dannym mikroperimetrii.

PURPOSE: This study assesses the effect of pleoptic treatment on the stability of visual fixation in children and adolescents with amblyopia of various degrees. MATERIAL AND METHODS: The effect of the treatment in 35 children (35 eyes) with amblyopia of various degrees was evaluated using the MP-1 Microperimeter. The stability was determined by two criteria - number of fixation point hits in the 2° zone and the width of the field of fixation. Children underwent a standard course of treatment. RESULTS: There was an improvement in the stability of visual fixation after treatment. The number of fixation point hits in the 2° zone increased from 44.8±4.1% to 52.6±3.8%. At the same time, the width of the field of fixation after treatment decreased from 6.5±0.7° to 5.2±0.5°. Visual acuity with correction in children with amblyopia correlates with the number of fixation point hits in the 2° zone (direct high correlation "+0.7") and width of the field of fixation (inverse high correlation "-0.7") both before and after the treatment. CONCLUSION: Stabilization of visual fixation was observed in patients with amblyopia of varying degrees after the pleoptic treatment.

Relationship between automated choroidal thickness measurements and retinal sensitivity using microperimetry in patients with myopia and different stages of myopic maculopathy.

PURPOSE: To assess the relationship between macular choroidal thickness (CT) measurements and retinal sensitivity (RS) in eyes with myopia and different stages of myopic maculopathy. METHODS: A masked, cross-sectional, and consecutive study involving patients with emmetropia/myopia (control group) and high myopia (HM) eyes. Automated choroidal thickness (CT) and manual outer retinal layer (ORL) thickness were acquired using swept-source optical coherence tomography, while retinal sensitivity (RS) assessed by microperimetry (MP3) in all regions of the macular Early Treatment Diabetic Retinopathy Study (ETDRS) grid. Comparisons were made between groups, and correlations were performed among these measurements, demographic and ocular parameters and myopic maculopathy classification. RESULTS: A total of 37 (74 eyes) patients were included in the study. The mean age was 39 ± 13 years, and 28 patients (76%) were female. HM eyes exhibited inferior best-corrected visual acuity and a more advanced myopic maculopathy classification compared to the control group. The mean macular CT were 255 and 179 µm in the control and HM eyes (P < 0.001), respectively. In the HM eyes, superior ETDRS region presented the greatest values. Mean RS in control and HM groups was 28 and 24 dB (P = 0.001), respectively. Inner temporal followed by superior, were the regions of higher RS. Mean ORL thickness was 83 and 79 µm (P < 0.001), in the control and HM groups, respectively. The inner temporal ETDRS region presented the thickest measure. CT correlated significantly with RS (r = 0.41, P < 0.001) and ORL thickness, (r = 0.58, P < 0.001), which also correlated with RS (r = 0.40, P < 0.001). Spherical equivalent, axial length and myopic maculopathy stage were the parameters that most correlated with CT, RS and ORL thickness. For every 100 µm increase in thickening of CT there was an average increase of 3.4 µm in ORL thickness and 2.7 dB in RS. Myopic maculopathy classification demonstrated influence only with CT. CONCLUSION: Myopia degree is related to ORL and choroidal thinning and deterioration of retinal sensitivity in some ETDRS regions of the macula. Choroidal thinning is associated to with a decline of retinal sensitivity, thinning of ORL, and worsening of myopic maculopathy classification, so new treatments are necessary to prevent myopia progression.

Microperimetry and Structural Risk Factors on OCT in Intermediate Age-Related Macular Degeneration.

PURPOSE: To determine the relationship between structural biomarkers on OCT that increase the risk of disease progression and microperimetric retinal sensitivity in patients with intermediate age-related macular degeneration (iAMD). DESIGN: Prospective cross-sectional, observational study. PARTICIPANTS: Forty-five eyes of 23 patients with iAMD. METHODS: Patients underwent OCT and microperimetry. OCT scans were evaluated for the risk factors intraretinal hyperreflective foci (HRF), hyporeflectivity within drusenoid lesions (HRDL), subretinal drusenoid deposits, double-layer sign (DLS), and drusen volume. Microperimetric retinal sensitivity was analyzed with a 33-point grid covering the macula. With a novel method of determining what part of the retina corresponded to each microperimetry point, a Voronoi diagram was constructed, dividing the macula in cells consisting of the region nearer to each point than any other. The Voronoi diagram was superimposed on the OCT, making it possible to determine the point-to-point location of the OCT risk factors. Univariable and multivariable linear mixed-effect models were used for analysis. MAIN OUTCOME MEASURES: Association between microperimetric retinal sensitivity and OCT risk factors at individual measuring points. RESULTS: One thousand four hundred seventy-nine points of retinal sensitivity and corresponding structural area on OCT were included in this study. Retinal sensitivity was significantly decreased with presence of the OCT risk factors HRF, HRDL, DLS, and drusen volume (all P < 0.001) when analyzed with the univariable linear mixed-effect model. The multivariable model showed a significant decrease of retinal sensitivity with presence of HRF (P < 0.001), DLS (P = 0.025), and greater drusen volume (P < 0.001). CONCLUSIONS: Presence of HRF, DLS, and greater drusen volume, all of which increase the risk of disease progression, is significantly and independently associated with decreased microperimetric retinal sensitivity in patients with iAMD. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Structural and functional characterization of an individual with the M285R KCNV2 hypomorphic allele.

BACKGROUND: Disease-causing variants in the KCNV2 gene are associated with "cone dystrophy with supernormal rod responses," a rare autosomal recessive retinal dystrophy. There is no previous report of hypomorphic variants in the disease. MATERIAL AND METHODS: Medical history, genetic testing, ocular examination, high-resolution retinal imaging including adaptive optics scanning light ophthalmoscopy (AOSLO), and functional assessments. RESULTS: A 16-year-old male with mild cone-rod dystrophy presented with reduced central vision and photophobia. Genetic testing showed two variants in KCNV2, c.614_617dupAGCG (p.207AlafsTer166) and c.854T>G (p.Met285Arg), the latter which was previously considered benign. Electrophysiological assessment revealed the pathognomic electroretinogram waveforms associated with KCNV2-retinopathy. Optical coherence tomography showed discrete focal ellipsoid zone disruption, while fundus autofluorescence was normal. Non-waveguiding cones corresponding to areas of loss of photoreceptor integrity were visible on adaptive optics scanning light ophthalmoscopy. Retinal sensitivity and fixation were relatively preserved, with a demonstrable deterioration after 14 months of follow-up. CONCLUSIONS: We provide functional and structural evidence that the variant M285R is disease-causing if associated with a loss-of-function variant. To the best of our knowledge, this is the first hypomorphic allele reported in KCNV2.

The Anatomic and Functional Outcomes of Ozurdex-Aided Vitrectomy in Proliferative Diabetic Retinopathy.

Purpose: To investigate the 3-months outcomes of patients who underwent intraoperative intravitreal injection of Ozurdex for proliferative diabetic retinopathy (PDR). Methods: This is a prospective randomized controlled clinical trial (ChiCTR2100043399). Seventy-one patients with PDR who had indications for surgery without intravitreal injection history within 3 months preoperatively were enrolled. Patients were randomly divided into three groups based on the medicine injected intraoperatively: Ozurdex, Conbercept, and Control group. The primary outcome is the best-corrected visual acuity (BCVA) within 3 months postoperatively. The secondary outcomes include the intraocular pressure (IOP), mean sensitivity, central retinal thickness and vessels perfusion. Results: The BCVA and the mean sensitivity improved in the three groups (F = 130.8, P < 0.0001; F = 34.18, P < 0.0001), but there was no statistical difference among the three groups (F = 0.858, P = 0.552; F = 0.964, P = 0.452). The IOP was no significant differences among the three groups within 3 months postoperatively (F = 0.881, P = 0.533). Compared with the other two groups, central retinal thickness (CRT) and outer retinal layer (ORL) thickness decreased significantly in patients of the Ozurdex group (F = 3.037, P = 0.008; F = 2.626, P = 0.018), especially in the diabetic macular edema (DME) patients (F = 2.761, P = 0.0164; F = 2.572, P = 0.0240). In macular region, superficial vascular plexus (SVP), intermediate capillary plexus (ICP) and deep capillary plexus (DCP) perfusion were not shown statistical difference at 3 months postoperatively in the all three groups compared with 1 day postoperatively (P > 0.05). Conclusion: Compared with the other two groups, anatomical outcomes was improved significantly in Ozurdex group for DR patients. Ozurdex may help to improve the visual acuity and visual sensitivity, and there is no significant difference in the change of IOP and microvascular improvement. Clinical Trial Registration: This trial is registered with the Chinese Clinical Trial Registry (http://www.chictr.org.cn, registration number ChiCTR2100043399).

Inner retinal thickness in Stargardt disease.

PURPOSE: To analyze the alterations at the level of the inner retina in patients affected by Stargardt disease (STGD1). METHODS: Cross-sectional investigation involving STGD1 patients with genetically confirmed diagnosis, who underwent optical coherence tomography (OCT), optical coherence tomography angiography (OCTA), and microperimetry. RESULTS: Overall, 31 patients (62 eyes) with genetically confirmed STGD1 were included in the study. Mean inner retinal thickness, vessel density of plexa, and retinal sensitivity resulted significantly reduced in STGD patients, compared with healthy controls (p < 0.05), both in the outer and in the inner ETDRS rings. Overall, 43% of eyes revealed an inner retinal thinning, whereas 21% and 35% showed a thicker or within normal range inner retina. CONCLUSIONS: Inner retina is irregularly altered in STGD1, showing variable quantitative alterations as detected on OCT. Inner retinal status might represent a useful biomarker to better characterize STGD1 and to ascertain the effects of new treatment approaches.

Functional and perfusion changes associated with silicone oil tamponade after macula-off rhegmatogenous retinal detachment surgery: an optical coherence tomography angiography/microperimetry study.

PURPOSE: The current study utilizes microperimetry and optical coherence tomography angiography (OCTA) to assess the optic nerve head vasculature, retinal microvasculature, and retinal sensitivity before and after silicone oil (SO) removal. METHODS: This prospective observational case series study involved 30 eyes subjected to silicone oil endotamponade. Microperimetry and OCTA were utilized to assess the vascular density (VD) of the macula and optic nerve head, as well as the retinal sensitivity (RS), of the participants preoperatively and 1 month following SO removal. The correlation between the various parameters of OCTA and microperimetry was evaluated. RESULTS: There was a significant improvement in the postoperative best-corrected visual acuity (BCVA) (p-value < 0.001) and the postoperative total RS, which was 6.38 ± 2.34 dB as compared to a mean preoperative total RS of 5.04 ± 2.06 dB (p-value < 0.001) and showing a significant increase in all rings. However, there was no significant difference in the pre and postoperative macular VD. On the other hand, there was a significant increase in the postoperative VD of the whole disk and the peripapillary capillary plexus, p-values < 0.001 and 0.002, respectively. CONCLUSION: The removal of SO resulted in significant improvements in retinal sensitivity, vision, and optic nerve perfusion. However, no significant change was observed in macular VD. CLINICAL TRIALS: gov Identifier: NCT04928196.