Digital histology of retinal microaneurysms as provided by dense B-scan (DART) OCTA: characteristics and clinical relevance in diabetic retinopathy.

BACKGROUND: Retinal microaneurysms (MAs) are among the earliest signs of diabetic retinopathy (DR) and can be classified in several subtypes by non-invasive multimodal retinal imaging. The main aim of the present study is to characterize retinal MAs perfusion properties and their blood flow network connectivity by means of Dense Automatic-RealTime (DART) OCTA technology, checking the relationship with the multimodal retinal imaging classification and testing the clinical impact of DART. METHODS: A cross-sectional, observational study setting was chosen. Multimodal retinal imaging included confocal multicolour, OCT, OCTA and DART OCTA. We classified retinal MAs accordingly with the recently proposed multimodal retinal imaging classification and we tested the role of DART OCTA for detecting retinal MAs blood flow network connectivity. We also tested the relationship with clinical parameters. RESULTS: We included 206 retinal MAs of 36 DR eyes. We categorized retinal MAs as red (70; 34%), mixed (106; 51%) and green (30; 15%), corresponding to precise characteristics on structural OCT and both (regular) enface and DART OCTA images. The agreement between en-face and DART OCTA techniques for detecting MAs perfusion was very high (overall ICC 0.98; p < 0.01). However, DART OCTA provided clearer visualization than enface OCTA for detecting the blood flow network connectivity of retinal MAs, especially looking at the afferent and efferent MAs capillaries. Multimodal retinal imaging classification of retinal MAs provided significant correlations with DR duration, DR stage, and macular capillary non-perfusion. CONCLUSIONS: DART OCTA provided several new insights on retinal MAs characteristics and their blood flow network connectivity.

Quantitative Optical Coherence Tomography Detection of New Neovascular Branches and Association With Exudation Recurrence in Neovascular Age-Related Macular Degeneration.

Purpose: The purpose of this study was to investigate the clinical role of multi-signal quantitative optical coherence tomography angiography (OCTA) perfusion sampling in neovascular age-related macular degeneration (AMD). Methods: The study was designed as a cross-sectional case series. We collected data from already treated macular neovascularization (MNV), characterized by (I) clinically relevant recurrent exudation, (II) nonclinically relevant recurrent exudation, and (III) inactive lesion. We proposed a new OCTA metric, calculating the gap between high-resolution (HR) and high-speed (HS) OCTA samplings, hypothesizing that this gap might improve the detection of new secondary MNV branches, being also associated with exudation recurrence. Main outcome measures were the HR-HS gap-based categorization of MNV lesions and the assessment of its association with exudative, minimally exudative, and inactive lesions. Results: Our cohort (which consisted of 32 MNV eyes; 32 patients; mean disease duration 5 years) was classified as type 1 (17; 53%), type 2 (11; 34%), or mixed type (4; 13%) MNV. Subretinal fibrosis was found in 17 out of 32 eyes (53%), whereas outer retinal atrophy involved 22 of 32 eyes (69%). HR-HS MNV gap was significantly different among MNV subgroups: 18% for the exudative subgroup, 12% for the minimally exudative subgroup, and 4% for the inactive subgroup. HR-HS gap significantly correlated with best corrected visual acuity (BCVA), disease duration, fibrosis, and outer retinal atrophy. Conclusions: HR-HS gap is a novel quantitative metric to detect the secondary novel branches of AMD-related MNV. This parameter is clinically relevant because it is associated with fluid recurrence. The integration of HR-HS gap in artificial intelligence models might help to predict MNV reactivation and to optimize treatment strategies.

Extensive Contact Lens Wear Modulates Expression of miRNA-320 and miRNA-423-5p in the Human Corneal Epithelium: Possible Biomarkers of Corneal Health and Environmental Impact.

The identification of new biomarkers of ocular diseases is nowadays of outmost importance both for early diagnosis and treatment. Epigenetics is a rapidly growing emerging area of research and its involvement in the pathophysiology of ocular disease and regulatory mechanisms is of undisputable importance for diagnostic purposes. Environmental changes may impact the ocular surface, and the knowledge of induced epigenetic changes might help to elucidate the mechanisms of ocular surface disorders. In this pilot study, we investigated the impact of extensive contact lens (CL) wearing on human corneal epithelium epigenetics. We performed ex vivo analysis of the expression of the miR-320 and miR-423-5p involved in the processes of cellular apoptosis and chronic inflammation. The human corneal epithelium was harvested from healthy patients before the photorefractive keratectomy (PRK). The patients were divided into two age- and sex-matched groups accordingly to CL wearing history with no CL wearers used as a control. The epithelium was stored frozen in dry ice at -80 °C and forwarded for miRNA extraction; afterwards, miRNA levels were detected using real-time PCR. Both miRNAs were highly expressed in CL wearers (p < 0.001), suggesting epigenetic modifications occurring in chronic ocular surface stress. These preliminary results show the relationships between selected miRNA expression and the chronic ocular surface stress associated with extensive CL use. MicroRNAs might be considered as biomarkers for the diagnosis of ocular surface conditions and the impact of environmental factors on ocular surface epigenetic. Furthermore, they might be considered as new therapeutic targets in ocular surface diseases.

Quantitative Multimodal Imaging Characterization of Intraretinal Cysts versus Degenerative Pseudocysts in Neovascular Age-Related Macular Degeneration.

OBJECTIVE: To differentiate intraretinal fluid (IRF) cysts from degenerative pseudocysts in neovascular age-related macular degeneration (AMD) by quantitative multimodal imaging. DESIGN: Observational, cross-sectional. PARTICIPANTS: Patients affected by macular neovascularization secondary to AMD. METHODS: All patients were analyzed by OCT, OCT angiography (OCTA), and dense automatic real-time (ART) OCTA. New-onset cysts were considered IRF, whereas those cysts that were found to be persistent for at least 3 months were categorized as degenerative pseudocysts. Intraretinal cysts were automatically segmented to calculate cyst circularity. Peri-cyst space was quantitatively analyzed to assess the presence of perfusion signal and hyperreflective foci (HF). MAIN OUTCOME MEASURES: Best-corrected visual acuity, cyst circularity, peri-cyst perfusion, peri-cyst HF, fibrosis, and outer retinal atrophy. RESULTS: We analyzed 387 cysts collected from 35 eyes of 35 patients with neovascular AMD (14 men; mean age, 80 ± 5 years). We classified 302 IRF cysts and 85 degenerative pseudocysts. Intraretinal fluid cysts were characterized by significantly higher circularity (0.86; range, 0.81-0.91), perfusion signal in the peri-cyst space, and peri-cyst HF in 89% of cases (all P < 0.05). Degenerative pseudocysts showed significantly lower circularity (0.68; range, 0.64-0.76), no perfusion signal in the peri-cyst space, and peri-cyst HF in only 29% of cases (all P < 0.05). The adopted quantitative metrics significantly correlated with disease duration, number of injections, fibrosis, and outer retinal atrophy. CONCLUSIONS: Intraretinal fluid cysts can be discriminated from degenerative pseudocysts using a quantitative multimodal imaging approach. These findings are clinically relevant and should be included in future training models for artificial intelligence algorithms to improve the diagnostic power and fluid monitoring in neovascular AMD. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Ophthalmologists' awareness of geographic atrophy: An Italian survey including 365 participants.

PURPOSE: Geographic atrophy (GA) is a severe complication of age-related macular degeneration (AMD) and leads to irreversible visual decline. To date, no effective treatment is available for GA patients. However, a number of new therapies have recently been approved and several others are in the pipeline. This rapid evolution of prospects for GA patients requires constant updating of ophthalmologists' understanding of GA and its management so as to provide the appropriate treatment. For this reason, Società Italiana di Scienze Oftalmologiche (S.I.S.O.) has designed a specific survey to gauge the position of Italian ophthalmologists in this regard. METHODS: The three hundred and sixty-five Italian ophthalmologists who agreed to take part received a seventeen-part questionnaire guaranteeing privacy and anonymity. The survey was compiled through an online portal and the results were sent directly to S.I.S.O. ETS. Two graders analyzed the data and recorded the results. RESULTS: The results showed a high level of self-assessed awareness and understanding of GA, as well as considerable willingness to further improve knowledge of the disease. Most of the participants claimed to have effective rules of conduct in place for managing GA patients, including prompt response, involving a high prevalence of nutraceutical prescriptions and lifestyle recommendations. CONCLUSIONS: This survey provided an overview of how GA patients are managed in Italy. The Italian ophthalmology community appears to be ready to adopt the upcoming treatments for GA.

Retinal Vessel Analysis and Microvascular Abnormalities in Patients with Philadelphia-Negative Chronic Myeloproliferative Neoplasms.

Background: Philadelphia-negative chronic myeloproliferative neoplasms are a group of clonal hematopoietic disorders including polycythemia vera, essential thrombocythemia, and primary myelofi-brosis. These neoplasms are characterized by an increased risk of thrombotic complications. Several studies have highlighted that the study of vessels of the retina offers the opportunity to visualize, in vivo, the damage to microcirculation that is common in various systemic pathologies. Methods: in our study, forty patients underwent an ophthalmological examination, using non-invasive imaging tech-niques, for analyses of their retinal vascularization. The objective was to correlate the findings ob-tained from this study of the retina with different markers of thrombotic risk, to demonstrate the usefulness of studying retinal vessels as a possible new prognostic biomarker of thrombotic risk in patients affected by Philadelphia-negative chronic myeloproliferative neoplasms. Results: retinal imaging demonstrated changes in the microcirculation, with a reduced vascular density of the deep and superficial capillary plexuses with respect to a normal group, and a correlation between retinal changes and blood parameters. Conclusions: additional research will allow us to determine whether retinal changes in individuals with chronic myeloproliferative neoplasms could be predictive of the development of thrombotic events in these subjects.

Clinical and Imaging Biomarkers Associated with Outer Retinal Atrophy Onset in Exudative Age-Related Macular Degeneration: A Real-Word Prospective Study.

INTRODUCTION: Macular neovascularization (MNV) secondary to age-related macular degeneration (AMD) is well managed by anti-vascular endothelial growth factor (anti-VEGF) intravitreal injections. However, outer retinal atrophy represents an unavoidable occurrence detected during follow-up. Several imaging metrics have been proposed as clinically relevant in stratifying the risk of onset of outer retinal atrophy. The main goal of this study is to evaluate the impact of noninvasive imaging metrics on the assessment of outer retinal atrophy onset in a large cohort of eyes with neovascular AMD managed in a real-world setting. METHODS: This study was a prospective, observational, case series. We included patients affected by newly diagnosed neovascular AMD, requiring anti-VEGF intravitreal injections. We collected clinical and imaging data, with a planned follow-up of 24 months. The multimodal imaging protocol included optical coherence tomography, optical coherence tomography angiography, and fundus autofluorescence. We collected noninvasive imaging metrics and we assessed the relationship with the morphological and functional outcome evaluated at 12-month and 24-month time points. RESULTS: We included 370 eyes of 370 patients with exudative AMD (210 male; mean age 79 ± 8 years). MNV were classified as follows: type 1, 198 (54%); type 2, 89 (24%); polypoidal choroidal vasculopathy, 29 (7%); and type 3, 54 (15%). A total of 120 out of 370 eyes (33%) showed complete outer retinal atrophy at the end of the 2-year follow-up. The presence of intraretinal fluid, thinning of the Sattler choroidal layer, late anti-VEGF switch, the overall number of anti-VEGF injections, and the perfusion characteristics of the MNV were found to be the most relevant factors associated with the onset of outer retinal atrophy. The other collected metrics were found to be less clinically relevant, also showing no cumulative effect in the multivariate analysis (p > 0.05). CONCLUSIONS: We identified imaging metrics significantly associated with the 2-year risk onset of outer retinal atrophy. These metrics might pave the way for the development of future customized anti-VEGF treatment strategies.

Clinical and optical coherence tomography biomarkers as prognostic factors in dexamethasone intravitreal implant for diabetic macular edema.

PURPOSE: Aim of the study was to evaluate the efficacy of dexamethasone (DEX) 0.7 mg intravitreal implant in patients with diabetic macular edema (DME) and serous retinal detachment (SRD), and to study the prognostic factors on a follow up of 12 months. METHODS: Forty eyes of twenty- six patients with centre involving DME and SRD, who underwent DEX implant, were enrolled. Best-corrected visual acuity (BCVA), Swept source OCT imaging and intraocular pressure were evaluated. Central macular thickness (CMT), vitreomacular adhesion (VMA), disorganization of retinal inner layers (DRILs), hyperreflective dots (HRD), SRD and ellipsoid zone (EZ) disruption were included in the analysis at baseline and 12 months after implant. RESULTS: According to our parametric analysis, at 12 months, BVCA improvement from 48.6 ± 23.4 letters to 53.3 ± 24.5 letters was statistically significant (p = 0.04), CMT decreased from 460 ± 99.52 µm to 322.9 ± 117 µm. The presence at baseline of VMA (p = 0.01), EZ disruption (p = 0.03) and DRILs (p = 0.04), were associated with poor BCVA improvement at the end of follow-up. CONCLUSION: In conclusion, OCT biomarkers can be considered significant prognostic factors for treatment outcome in patients with DME undergoing DEX intravitreal implant.

Linear streaks associated with retinitis pigmentosa.

PURPOSE: To describe a phenotypical manifestation characterized by the identification of peripheral linear streaks associated with retinitis pigmentosa (RP). METHODS: Study design is a prospective observational case series. All consecutive patients affected by RP underwent a complete ophthalmological examination. The diagnosis of peripheral linear streaks was based on the identification of curvilinear atrophic streaks in the periphery of the retina. RESULTS: Overall, six out of 140 patients (4.2%) were affected by peripheral linear streaks associated with RP. A single patient showed also punched out chorioretinal lesions at the posterior pole, with macular neovascularization development over the follow-up, treated with ranibizumab injections. CONCLUSIONS: RP phenotypical manifestation characterized by peripheral linear streaks is infrequent and may provide additional evidence to support the contribution of inflammation in the pathogenesis of RP.

Topical Antiseptics in Minimizing Ocular Surface Bacterial Load Before Ophthalmic Surgery: A Randomized Controlled Trial.

PURPOSE: To investigate the reduction of the ocular surface bacterial load induced by 2 commercially available ophthalmic antiseptic formulations, povidone-iodine (PVI) 0.6% and chlorhexidine (CLX) 0.02%, before ocular surgery. DESIGN: Randomized controlled trial. METHODS: Seventy adult patients undergoing intraocular surgery (phacoemulsification) were randomized to receive in the index eye PVI (group A) 4 times a day for 3 days or CLX (group B) 4 times a day for 3 days before surgery. The untreated eye was used as control. A conjunctival swab was taken in both eyes before (T0) and after (T1) therapy. Microbial DNA was quantified with real-time polymerase chain reaction (PCR) analysis. The Mick algorithm was used to compare the abundance of each genus/genera against the distribution of abundances from the reference. At T1, patients filled a questionnaire to evaluate therapy-induced symptoms. Primary outcome was the reduction of bacterial DNA at T1 (microbial load), vs control arm, expressed as mean number of real-time PCR cycle times (CTs). Secondary outcomes were taxonomic composition, differential abundance, and therapy-induced ocular symptoms. RESULTS: The T0-T1 difference in CT was significant in group B, but not in group A (mean [95% CI], 0.99 [0.33] vs 0.26 [0.15], P < .001, and 0.65 [0.3] vs 0.45 [0.41], P = .09, respectively). The taxonomic composition, alpha, and beta diversity remained consistent at all time points in both groups. The rate of patients reporting therapy-induced ocular symptoms and the mean discomfort grade were greater in group A than in group B (97% vs 26% and 4.97±2.48 vs 0.66±1.53, respectively). CONCLUSIONS: Compared with PVI 0.6%, CLX 0.02% induced a greater reduction of ocular surface bacterial load, with no significant alterations of the taxonomic composition. Moreover, CLX was better tolerated than PVI.

Non-vasogenic cystoid maculopathy in autosomal recessive bestrophinopathy: novel insights from NIR-FAF and OCTA imaging.

BACKGROUND: Autosomal Recessive Bestrophinopathy (ARB) is an inherited retinal disease caused by biallelic mutations in the BEST1 gene. Herein, we report the multimodal imaging findings of ARB presenting with cystoid maculopathy and investigate the short-term response to combined systemic and topical carbonic anhydrase inhibitors (CAIs). MATERIAL AND METHODS: An observational, prospective, case series on two siblings affected by ARB is presented. Patients underwent genetic testing and optical coherence tomography (OCT), blue-light fundus autofluorescence (BL-FAF), near-infrared fundus autofluorescence (NIR-FAF), fluorescein angiography (FA), MultiColor imaging, and OCT angiography (OCTA). RESULTS: Two male siblings, aged 22 and 16, affected by ARB resulting from c.598C>T, p.(Arg200*) and c.728C>A, p.(Ala243Glu) BEST1 compound heterozygous variants, presented with bilateral multifocal yellowish pigment deposits scattered through the posterior pole that corresponded to hyperautofluorescent deposits on BL-FAF. Vice versa, NIR-FAF mainly disclosed wide hypoautofluorescent areas in the macula. A cystoid maculopathy and shallow subretinal fluid were evident on structural OCT, albeit without evidence of dye leakage or pooling on FA. OCTA demonstrated disruption of the choriocapillaris throughout the posterior pole and sparing of intraretinal capillary plexuses. Six months of combined therapy with oral acetazolamide and topical brinzolamide resulted in limited clinical benefit. CONCLUSIONS: We reported two siblings affected by ARB, presenting as non-vasogenic cystoid maculopathy. Prominent alteration of NIR-FAF signal and concomitant choriocapillaris rarefaction on OCTA were noted in the macula. The limited short-term response to combined systemic and topical CAIs might be explained by the impairment of the RPE-CC complex.

Association of Circulating Antiretinal Antibodies With Clinical Outcomes in Retinitis Pigmentosa.

Purpose: To determine if circulating antiretinal antibodies (ARAs) differ between patients affected by retinitis pigmentosa (RP) and control participants and to assess whether ARAs are associated with clinical outcomes in patients with RP. Methods: Cross-sectional study involving a group of patients clinically diagnosed with RP and a control group of healthy participants. Serum autoantibodies against enolase, heat shock protein 70 (HSP70), and carbonic anhydrase II (CAII) were tested in all participants using Jess capillary Western blot. We compared ARA prevalence between the RP and control groups and investigated the association of serum ARA positivity with macular edema and vitreomacular disorders in patients affected by RP. Results: Thirty-six patients affected by RP and a control group of 39 healthy individuals were included. Overall, at least one ARA positivity was detected in 89% and 80% of participants in the RP and control groups, respectively. We observed a similar prevalence of anti-CAII and anti-enolase ARA between patients and controls (P = 0.87 and P = 0.35, respectively). Sera from patients with RP tested positive for anti-HSP70 ARAs more frequently than those from controls (53% vs. 36%), albeit without reaching statistical significance (P = 0.29). Among the 72 eyes with RP, 25% presented with macular edema (most often bilateral) and 33% with epiretinal membrane and/or lamellar macular hole. None of the three ARAs was associated with an increased risk of any macular complications in eyes affected by RP (all P > 0.05). Conclusions: The prevalence of circulating ARAs against enolase, HSP70, and CAII is similar between patients affected by RP and healthy individuals. Our results provide evidence against the association of ARAs with macular edema and vitreomacular interface disorders in RP.

The Clinical Role of the Choroidal Assessment in High Myopia: Characteristics and Association With Neovascular and Atrophic Complications.

Purpose: To investigate the clinical utility of choroidal quantitative assessment associated with the presence of macular neovascularization (MNV) or atrophy in high myopia. Methods: The study was designed as a retrospective case series with two-year follow-up. We measured choroidal thickness (CT) and the presence and subtype of dome-shaped macula (DSM). In DSM eyes we also calculated the presence and type of choroidal deepening (CD). The eyes were categorized as Subgroup 1 (high myopia without complications), Subgroup 2 (high myopia complicated by MNV), and Subgroup 3 (high myopia complicated by macular or posterior pole atrophy). Main outcome measures were the detection of significant CT cutoffs associated with the three subgroups of eyes and the clinical impact of DSM and CD subtypes. Results: Our cohort (190 eyes affected by high myopia) was categorized as Subgroup 1 (66 eyes), Subgroup 2 (72 eyes) and Subgroup 3 (52 eyes). Baseline CT values allowed to separate the subgroups with myopic-related complications (area under the curve = 0.85; P < 0.05). In Subgroup 1, vertical DSM was the most frequent (54%), with CD absence characterizing the 46% of cases. Round DSM was the most represented subtype in Subgroup 2 (49%), with 55% of sub-dome CD subtypes; in these cases, MNV resulted always localized in the fovea. Subgroup 3 equally shown horizontal or vertical DSM (53% and 47%, respectively), with 80% of cases showing peri-dome CD. Conclusions: Choroidal quantitative assessment can categorize three high myopia subgroups. MNV subgroup is characterized by intermediate choroidal thinning and higher prevalence of round DSM with sub-dome CD.

The Localization of Intraretinal Cysts Has a Clinical Role on the 2-Year Outcome of Neovascular Age-Related Macular Degeneration.

OBJECTIVE: To assess the relationship between ≥ 1 localizations of intraretinal fluid (IRF) within retinal layers and the 2-year outcome in a cohort of neovascular age-related macular degeneration (AMD) eyes. DESIGN: Retrospective case series. PARTICIPANTS: Two hundred forty-three eyes of 243 AMD patients affected by type 1 and type 2 macular neovascularization (MNV). METHODS: We analyzed data considering MNV onset, 1-year, and 2-year timepoints. Optical coherence tomography images were used to classify MNV types, distinguish different types of fluids and assess IRF localization within retinal layers. A subcohort of eyes were also analyzed by OCT angiography. MAIN OUTCOME MEASURES: The association between IRF cyst localization and both visual outcome and onset of outer retinal atrophy at 2-year follow-up. RESULTS: Macular neovascularizations were distributed as type 1 (69%) and type 2 (31%). The mean number of intravitreal injections was 7 ± 2 at 1-year follow-up and 5 ± 2 at 2-year follow-up. Baseline best-corrected visual acuity was 0.4 ± 0.3 logarithm of the minimum angle of resolution, improving to 0.3 ± 0.4 at 2-year follow-up (P < 0.01). Outer retinal atrophy occurred in 24% of cases at 1 year and 39% of cases at 2-year follow-up. Intraretinal fluid localizations at the level of IPL-INL and OPL-ONL at baseline were associated with the worst functional and anatomical outcome. Moreover, the presence of IRF at baseline was associated with greater impairment of the intraretinal vascular network. CONCLUSIONS: The localization of IRF at the level of IPL-INL and OPL-ONL retinal layers represents a negative prognostic biomarker for the morphologic and functional outcomes of neovascular AMD. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Association Between Genotype and Phenotype Severity in ABCA4-Associated Retinopathy.

Importance: ABCA4-associated retinopathy is a common inherited retinal disease, and its phenotype spans from late-onset macular dystrophy to extensive cone-rod degeneration. Over 2000 disease-causing variants in the ABCA4 gene have been identified. Objective: To investigate genotype-phenotype correlations in ABCA4-associated retinopathy. Design, Setting, and Participants: This cohort study took place at a single referral center for inherited retinal diseases in Italy. Data were prospectively acquired from January 2015 to June 2022. Patients diagnosed with an inherited retinal disease related to biallelic ABCA4 variants were included for analysis. Exposure: Genotype, classified into 4 groups according to the presence of the (1) p.Gly1961Glu allele, (2) a hypomorphic allele, (3) at least 1 moderate variant (moderate genotypes), or (4) 2 biallelic severe variants (severe genotypes). Main Outcomes and Measures: Total decreased autofluorescence (TDAF) and definitely decreased autofluorescence (DDAF) areas, inner and outer retinal volumes, and the respective progression rate. Results: A total of 71 patients (median [IQR] age, 34 [22.4-47.2] years; 40 [56%] female) were included in the study, and 54 (76%) were followed up for a median (IQR) of 3.5 (1.6-4.7) years. Compared with moderate genotypes, those with the p.Gly1961Glu allele had smaller TDAF lesions by 61% (95% CI, -78% to -33%; P < .001) and DDAF lesions by 77% (95% CI, -93% to -18%; P = .02), along with slower growth rates for both TDAF (0.05 mm/y; 95% CI, 0.01-0.07; P < .001) and DDAF (0.06 mm/y; 95% CI, 0-0.12; P = .004). Hypomorphic alleles were associated with a thicker inner (+0.19 mm3; 95% CI, +0.02 to +0.36; P = .03) and outer retinal volume (+0.16 mm3; 95% CI, +0.03 to +0.28; P = .01) compared with moderate genotypes as well as a slower TDAF growth rate (0.05 mm/y; 95% CI, 0.01-0.08; P = .007). Severe genotypes had a 7-fold larger TDAF area (95% CI, 3.4-14.7; P < .001) and 11-fold larger DDAF area (95% CI, 2.9-42.1; P < .001) compared with moderate genotypes, along with faster growth rates estimated at 0.16 mm/y for TDAF (95% CI, 0.12-0.20; P < .001) and 0.17 mm/y for DDAF (95% CI, 0.12-0.23; P < .001). Conclusions and Relevance: In this study of ABCA4-associated retinopathy, a 4-tier classification of genotypes was found to capture substantial variation in disease phenotype severity. These findings could prove beneficial for the prognostication of patients and warrant consideration of genotype in the design of future clinical trials.

Fixation Location and Stability in Best Vitelliform Macular Dystrophy.

Purpose: To analyze fixation location and stability in best vitelliform macular dystrophy (BVMD) and test their association with best-corrected visual acuity (BCVA). Design: Observational, cross-sectional study. Participants: Thirty patients (55 eyes) affected by genetically confirmed BVMD were followed up at the Retinal Heredodystrophies Unit of IRCCS San Raffaele Scientific Institute, Milan. Methods: Patients underwent testing with macular integrity assessment (MAIA) microperimeter. Fixation location was measured as distance in degrees (°) between preferred retinal locus (PRL) and estimated fovea location (EFL); fixation was defined as eccentric when the distance between PRL and EFL exceeded 2°. Fixation stability was graded as stable, relatively unstable, or unstable and expressed as bivariate contour ellipse area (BCEA, °2). Main Outcome Measures: Fixation location and stability. Results: The median distance of the PRL from the anatomic fovea was 0.7°, and fixation location was eccentric in 27% of eyes. Fixation was graded as stable in 64% of eyes, relatively unstable in 13%, and unstable in 24%, with a median 95% BCEA of 6.2°2. The atrophic/fibrotic stage was associated with worse fixation parameters (all P < 0.01). Both PRL eccentricity and fixation stability were linearly associated with BCVA: every 1° increase in PRL eccentricity was associated with a 0.07 logarithm of the minimum angle of resolution (logMAR) worse BCVA (P < 0.0001) while every 1°2 increase in 95% BCEA was associated with a 0.01 logMAR worse BCVA (P < 0.001). No significant intereye correlation was found for PRL eccentricity and fixation stability, as well as no association between the patient's age and fixation parameters. Conclusions: We demonstrated that most eyes affected by BVMD retain a central stable fixation and provided evidence that both fixation eccentricity and stability are strongly associated with visual acuity in BVMD. These parameters may serve as secondary end points for future clinical trials. Financial Disclosures: Proprietary or commercial disclosure may be found after the references.

Foveal Eversion is Associated with High Persistence of Macular Edema and Visual Acuity Deterioration in Retinal Vein Occlusion.

INTRODUCTION: Foveal eversion (FE) is a recently described optical coherence tomography (OCT) finding associated with negative outcome in diabetic macular edema. The main goal of the present study was to investigate the role of the FE metric in the diagnostic workup of retinal vein occlusion (RVO). METHODS: This study was a retrospective, observational case series. We included 168 eyes (168 patients) affected by central RVO (CRVO) and 116 eyes (116 patients) affected by branch (RVO). We collected clinical and imaging data from CRVO and BRVO eyes affected by macular edema with a minimum follow-up of 12 months. On structural OCT, we classified FE as pattern 1a, characterized by thick vertical intraretinal columns, pattern 1b, presenting thin vertical intraretinal lines, and pattern 2, showing no signs of vertical lines in the context of the cystoid macular edema. For statistical purposes, we considered data collected at baseline, after 1 year and at the last follow-up. RESULTS: The mean follow-up was 40 ± 25 months for CRVO eyes and 36 ± 24 months for BRVO eyes. We found FE in 64 of 168 CRVO eyes (38%) and in 25 of 116 BRVO eyes (22%). Most of the eyes developed FE during the follow-up. For CRVO eyes, we found 6 eyes (9%) with pattern 1a, 17 eyes (26%) with pattern 1b and 41 eyes (65%) with pattern 2. Of those BRVO eyes with FE, we found 8 eyes (32%) with pattern 1a + 1b and 17 eyes (68%) with pattern 2. In both CRVO and BRVO the presence of FE was significantly associated with higher persistence of macular edema and worse outcome, with FE pattern 2 representing the most severe condition. Remarkably, FE patterns 1a and 1b were characterized by BCVA stability over the follow-up, whereas FE pattern 2 showed significant bestcorrected visual acuity (BCVA) worsening at the end of the follow-up. CONCLUSIONS: FE can be considered a negative prognostic biomarker in RVO, associated with higher persistence of macular edema and worse visual outcome. Müller cell impairment might represent the pathogenic mechanism leading to the loss of macular structural support and impairment of fluid homeostasis.

High-resolution/High-Speed Gap Can Distinguish Different Intraretinal Perfusion Signals by Optical Coherence Tomography Angiography.

Purpose: The development of optical coherence tomography angiography (OCTA) has radically changed the diagnostic assessment of the intraretinal vascular network. Two different OCTA acquisition modalities have recently been introduced in clinical practice, namely high-resolution (HR) and high-speed (HS) scans. HR OCTA requires more acquisition time and provides higher quality data, whereas HS OCTA is faster but furnishes lower quality data. The main aim of the present study is to gauge how much extra blood flow perfusion information can be obtained through the combined use of HR and HS OCTA. Methods: We compared HR and HS OCTA acquisitions to assess the reliability of both techniques, also putting forward a new set of quantitative metrics to measure the HR/HS OCTA gap and to highlight different perfusion information. Results: In essence, both HR and HS OCTA acquisitions proved highly feasible in detecting the intraretinal vascular flow signal, as confirmed by the stability of quantitative OCTA metrics, thus displaying their suitability for use in clinical practice. We detected an HR/HS overlapping gap of 21.6 ± 6.5% for intraretinal capillaries, and 4.3 ± 1.2% for choriocapillaris, highlighting the greater information obtained by HR OCTA. Conclusions: This novel HR/HS OCTA gap assessment might pave the way for the development of new quantitative metrics for retinal diseases that would focus on the earlier detection of perfusion impairment and relate it to the stage of the disease and its progression. Translational Relevance: This study proposes a new quantitative way to detect different perfusion signals based on OCTA. The findings presented in this paper can lay the foundations for the development of new quantitative metrics focused on the separate analysis of high flow and low flow signals, enabling very early changes in intraretinal perfusion to be detected.

Refractive surgery and dry eye.

Refractive surgery is one of the most common elective surgeries performed worldwide. The incidence of dry eye disease (DED) after corneal refractive surgery varies among different studies. Pre-existing untreated DED has been identified as a risk factor for postsurgical dry eye symptoms. On the basis of both evidence and clinical experience, some recommendations for ocular surface and DED management pre- and post-refractive surgery are described. In aqueous deficiency Dry Eye Disease, preservative-free lubricating drops should be preferred, in addition to ointment and gel forms. Topical anti-inflammatory agents (Cyclosporine 0.1%, hydrocortisone phosphate, fluorometholone) should be used for 3-6 months in cases of ocular surface damage. The therapy of evaporative DED includes lifestyle modifications, lid hygiene (either performed by the patient or offered as professional lid hygiene by the physician), use of lubricating eye drops with lipid components, topical and/or systemic antibiotic treatment with anti-inflammatory properties and Intense Pulsed Light (IPL-) Treatment for meibomian gland dysfunction.