The preproliferative stage in type 2 macular telangiectasia (MacTel type 2).

PURPOSE: To study clinical and imaging features of various stages of macular telangiectasia (MacTel type 2). METHODS: In this retrospective study, cases of MacTel type 2 with fluorescein angiography (FA), optical coherence tomography (OCT) and OCT-angiography (OCTA) imaging were included. Based on angiographic perifoveal fluorescence, two groups were formed: group 1: diffuse hyperfluoroscence and group 2: diffuse + focal hyperfluoroscence. Later, based on OCT features, group 2 was subdivided into group 2A: without SRNVM and group 2B: with SRNVM. Clinical, FA, OCT and OCTA features were analysed. Eyes showing conversion to the proliferative stage at final visit were noted. RESULTS: Ninety-four eyes of 48 patients were included. Group 1 (n = 28) showed diffuse perifoveal hyperfluoroscence, hyperreflective middle retinal layers, absent SRNVM (p = 0.006) on OCT and dilated perifoveal capillaries in deep capillary plexus (DCP) on OCTA. Group 2A (n = 40) showed diffuse + focal perifoveal hyperfluoroscence, hyperreflective middle retinal layers (p = 0.001), hyporeflective outer retina cavities (p = 0.021), absent SRNVM with dilated and bunching perifoveal capillaries (p = 0.004) in DCP. Group 2B (n = 26) showed late diffuse + focal perifoveal hyperfluoroscence, foveal contour irregularity (p = 0.002), retinal pigment clumps (p = 0.015) and SRNVM on OCT with bunching of capillaries in DCP and vessels in outer retina (p = 0.002). Five eyes showed conversion to group 2B at final visit. CONCLUSION: There exists a distinct disease stage called "preproliferative" MacTel type 2 showing clinical features of non-proliferative disease, diffuse + focal perifoveal hyperfluoroscence on FA, absent SRNVM on OCT and bunching perifoveal capillaries in DCP on OCTA. Its identification is important for suspecting proliferative disease, planning management and follow-up visit accordingly.

Influence of fellow eye on the diagnosis and classification of central serous chorioretinopathy.

PURPOSE: To assess the influence of fellow eye information on diagnosis and classification of central serous chorioretinopathy (CSCR) using multimodal imaging-based classification. METHODS: This was a retrospective, observational study including patients with CSCR with unilateral or bilateral involvement. Multimodal images of both eyes of each patient were compiled and presented to two masked retina specialists subdivided into three groups: (1) both eye data, (2) right eye data and (3) left eye data. The masked observers graded the CSCR as per the new CSCR classification into simple and complex CSCR in three different scenarios as subdivided above. Interobserver and intraobserver agreement was assessed using Cohen's kappa (95% confidence intervals). RESULTS: A total of 206 eyes of 103 patients with unilateral or bilateral CSCR were graded. We found a "strong" intraobserver and interobserver agreement when one eye versus both eye data was provided in terms of "simple CSCR" or "complex CSCR" (kappa value = 0.77 and 0.87, p < 0.001, and kappa value = 0.85 and 0.76, p < 0.001, respectively). Forty-three eyes (10.55%) showed discrepancy in classification between observers for individual eyes, whereas only 13 eyes (6.53%) showed discrepancy between observers when both eye data was provided. CONCLUSION: We conclude that fellow eye information was helpful in solving diagnostic dilemmas and reached 85% consensus in the diagnosis of CSCR between the observers. We found that information of fellow eyes led to a discrepancy only in 6.53% cases with 2.42% cases that had a controversial diagnosis of CSCR. Multimodal imaging-based CSCR classification provides objective approach to diagnose and classify CSCR.

Diabetic Retinopathy and Diabetic Macular Edema in People With Early-Onset Diabetes.

This study examined the clinical profile, treatment profile, and vision outcomes of people ≤40 years of age with diabetes and diabetic macular edema (DME). Within this age-group, the prevalence of center-involving DME was 16%, with 74% of eyes showing cystoid edema, 37% showing spongiform edema, and 41% having neurosensory detachment. Longer diabetes duration (P = 0.001) and greater severity of diabetic retinopathy (P <0.001) were associated with DME prevalence. Thus, regular and more frequent follow-up, as well as early and aggressive treatment of diabetic eye disease, are required in people diagnosed early with diabetes.

Intercalary membrane break and detachment causes intrachoroidal cavitation in macular coloboma.

PURPOSE: To describe the clinical and imaging features in a series of patients diagnosed with macular coloboma (MC) and intrachoroidal cavitation (ICC). METHODS: Patients diagnosed with MC based on clinical examination between June 2017 and July 2021 were retrieved from the electronic medical record system and were included in the study. Colour fundus photographs, optical coherence tomography (OCT) and Multicolour® imaging scans of these patients were analysed. RESULTS: We identified 16 eyes of 11 patients with MC on fundus examination. Based on OCT imaging features, conforming variant of MC was seen in 9 (56%) eyes and non-conforming variant in 7 (44%) eyes. No eyes with MC in the study showed features of both conforming and non-conforming varieties simultaneously. In the non-conforming variety of MC with presence of intercalary membrane break, ICC was identified in 5 (71%) of these eyes. ICC in MC appeared as flat, dark greenish areas with or without an orange-coloured boundary abutting the margin of the coloboma on Multicolour® imaging. CONCLUSION: In 31% eyes, ICC was seen in non-conforming type of MC and was well-identified on Multicolour® imaging. It appears that presence of intercalary membrane break and detachment are prerequisites for developing ICC.

Intracystic hyperreflective material in centre-involving diabetic macular oedema.

PURPOSE: To report evolution and predictive value of intracystic hyperreflective material (ICHRM) on optical coherence tomography (OCT) in centre-involving diabetic macular oedema (CI-DME). METHODS: Demographic and OCT features of patients with treatment-naïve CI-DME were analysed retrospectively. OCT parameters noted were macular oedema type, ICHRM presence, presence of hyperreflective spots, disorganised inner retinal layers and outer retinal layers integrity. Eyes were grouped into group 1 CI-DME without ICHRM and group 2 CI-DME with ICHRM. Univariate and multivariate linear regression analyses were done to study the correlation between various OCT features and final vision. RESULTS: In this study, 62 eyes of 50 patients were included in group 1 and 61 eyes of 51 patients in group 2. Mean presenting logMAR vision in groups 1 and 2 was 0.374 ± 0.346 and 0.523 ± 0.369 respectively. Poor final visual acuity was noted in CI-DME with ICHRM group (p = 0.015). On linear regression analysis, 3 OCT features, namely, ICHRM presence (p = 0.034), inner segment-outer segment layer disruption (p = 0.001) and ellipsoid zone defects (p = 0.003), were associated with poor final vision. More intravitreal anti-VEGF (2.98 vs 0.629) and steroid (1.51 vs 0.242) injections were required for macular oedema resolution in ICHRM group. CONCLUSION: This study is the first to assess the ICHRM on OCT as predictor for treatment outcome in DME eyes. We described its evolution during the DME management and its plausible influence on intravitreal therapy. We believe that this finding has the potential to become a novel biomarker for predicting the visual outcome in DME.

Role of multicolour imaging in post-fever retinitis involving posterior pole.

PURPOSE: To describe composite multicolour (MC) imaging features along with the monocoloured fundus reflectance images in active and resolving stages of post-fever retinitis (PFR). METHODS: Retrospective image analysis of cases of PFR who underwent dilated retinal clinical examination followed by optical coherence tomography and MC imaging. RESULTS: Twenty-five eyes of 18 patients diagnosed with PFR were included. There were 11 males and 7 females. Mean age of patients was 30.63 years. The retinitis lesion appeared bright white on MC image and white mainly on blue and green reflectance images during the active stages of PFR. The lesion appeared dull-grey to greyish white during the resolving stages and as dull-green in resolved cases. The active stages showed the presence of intraretinal/subretinal fluid which appeared as green colour on MC images and less green to normal during resolving stages. Hard exudates were seen as bright yellow- or orange-coloured spots on MC image during the resolving stages of the disease. CONCLUSION: The different stages of PFR show different colour on multicolour image and different reflectance patterns on individual colour reflectance channels. Hence, multimodal fundus imaging with different wavelength can be helpful for differentiation of activity in PFR.

Fibrin-Glue-Assisted Surgery for Idiopathic Macular Holes.

METHODS: This pilot clinical trial included 10 eyes of 10 patients with idiopathic MH, where PPV along with ILMP was done. Fibrin glue was used as a tamponade, and no postoperative positioning was given to any patient. The primary outcome measure was successful anatomical closure of the MH. The secondary outcome measures were postoperative improvement in best-corrected visual acuity (BCVA) and any complications of the procedure. RESULTS: The median age of patients was 62.5 years. Eight eyes were pseudophakic and two were phakic. The mean basal diameter of the MH was 1193 microns. The mean minimal linear diameter was 652 microns. Successful anatomic closure of MH was achieved in eight cases. The median BCVA improved from a Snellen equivalent of 20/100 preoperatively to 20/60 at 1 month postoperatively. The median follow-up period was 4 months. CONCLUSION: The findings of this study suggest that the use of fibrin glue can be useful in patients where postoperative positioning is difficult.

Evaluation of Systemic Risk Factors in Patients with Diabetes Mellitus for Detecting Diabetic Retinopathy with Random Forest Classification Model.

BACKGROUND: This study aims to assess systemic risk factors in diabetes mellitus (DM) patients and predict diabetic retinopathy (DR) using a Random Forest (RF) classification model. METHODS: We included DM patients presenting to the retina clinic for first-time DR screening. Data on age, gender, diabetes type, treatment history, DM control status, family history, pregnancy history, and systemic comorbidities were collected. DR and sight-threatening DR (STDR) were diagnosed via a dilated fundus examination. The dataset was split 80:20 into training and testing sets. The RF model was trained to detect DR and STDR separately, and its performance was evaluated using misclassification rates, sensitivity, and specificity. RESULTS: Data from 1416 DM patients were analyzed. The RF model was trained on 1132 (80%) patients. The misclassification rates were 0% for DR and ~20% for STDR in the training set. External testing on 284 (20%) patients showed 100% accuracy, sensitivity, and specificity for DR detection. For STDR, the model achieved 76% (95% CI-70.7%-80.7%) accuracy, 53% (95% CI-39.2%-66.6%) sensitivity, and 80% (95% CI-74.6%-84.7%) specificity. CONCLUSIONS: The RF model effectively predicts DR in DM patients using systemic risk factors, potentially reducing unnecessary referrals for DR screening. However, further validation with diverse datasets is necessary to establish its reliability for clinical use.

Recommendations for initial diabetic retinopathy screening of diabetic patients using large language model-based artificial intelligence in real-life case scenarios.

PURPOSE: To study the role of artificial intelligence (AI) to identify key risk factors for diabetic retinopathy (DR) screening and develop recommendations based on clinician and large language model (LLM) based AI platform opinions for newly detected diabetes mellitus (DM) cases. METHODS: Five clinicians and three AI applications were given 20 AI-generated hypothetical case scenarios to assess DR screening timing. We calculated inter-rater agreements between clinicians, AI-platforms, and the "majority clinician response" (defined as the maximum number of identical responses provided by the clinicians) and "majority AI-platform" (defined as the maximum number of identical responses among the 3 distinct AI). Scoring was used to identify risk factors of different severity. Three, two, and one points were given to risk factors requiring screening immediately, within a year, and within five years, respectively. After calculating a cumulative screening score, categories were assigned. RESULTS: Clinicians, AI platforms, and the "majority clinician response" and "majority AI response" had fair inter-rater reliability (k value: 0.21-0.40). Uncontrolled DM and systemic co-morbidities required immediate screening, while family history of DM and a co-existing pregnancy required screening within a year. The absence of these risk factors required screening within 5 years of DM diagnosis. Screening scores in this study were between 0 and 10. Cases with screening scores of 0-2 needed screening within 5 years, 3-5 within 1 year, and 6-12 immediately. CONCLUSION: Based on the findings of this study, AI could play a critical role in DR screening of newly diagnosed DM patients by developing a novel DR screening score. Future studies would be required to validate the DR screening score before it could be used as a reference in real-life clinical situations. CLINICAL TRIAL REGISTRATION: Not applicable.

Recommendations for diabetic macular edema management by retina specialists and large language model-based artificial intelligence platforms.

PURPOSE: To study the role of artificial intelligence (AI) in developing diabetic macular edema (DME) management recommendations by creating and comparing responses to clinicians in hypothetical AI-generated case scenarios. The study also examined whether its joint recommendations followed national DME management guidelines. METHODS: The AI hypothetically generated 50 ocular case scenarios from 25 patients using keywords like age, gender, type, duration and control of diabetes, visual acuity, lens status, retinopathy stage, coexisting ocular and systemic co-morbidities, and DME-related retinal imaging findings. For DME and ocular co-morbidity management, we calculated inter-rater agreements (kappa analysis) separately for clinician responses, AI-platforms, and the "majority clinician response" (the maximum number of identical clinician responses) and "majority AI-platform" (the maximum number of identical AI responses). Treatment recommendations for various situations were compared to the Indian national guidelines. RESULTS: For DME management, clinicians (ĸ=0.6), AI platforms (ĸ=0.58), and the 'majority clinician response' and 'majority AI response' (ĸ=0.69) had moderate to substantial inter-rate agreement. The study showed fair to substantial agreement for ocular co-morbidity management between clinicians (ĸ=0.8), AI platforms (ĸ=0.36), and the 'majority clinician response' and 'majority AI response' (ĸ=0.49). Many of the current study's recommendations and national clinical guidelines agreed and disagreed. When treating center-involving DME with very good visual acuity, lattice degeneration, renal disease, anaemia, and a recent history of cardiovascular disease, there were clear disagreements. CONCLUSION: For the first time, this study recommends DME management using large language model-based generative AI. The study's findings could guide in revising the global DME management guidelines.

Choroidal changes in posterior microphthalmos.

PURPOSE: To describe the choroidal variations in posterior microphthalmos (PM). METHODS: In this observational case series, four eyes of two patients diagnosed as PM based on the characteristic clinical features were included. Multimodal retinal imaging with clinical fundus documentation using ultrawide field fundus camera, optical coherence tomography (OCT) and indocyanine green angiography (ICGA) was done for these cases. RESULTS: Multimodal imaging of these cases confirmed the variations in the choroid in PM cases. In both cases, on OCT, the retina and choroid were thick. retinal papillomacular fold (RPMF) was noted in all four eyes. On ICGA, the dye transit time from the arm to choroid and retina were within normal limits. Choroidal vasculature in the far retinal periphery was reduced and was noted as hypocyanescent areas anterior to the equator while the density of choroidal vessels was significantly more posterior to the equator. Vortex veins were not visualised in both cases. CONCLUSION: Choroidal structure and vessels undergo alterations in PM. Further validation of these findings is required in a larger cohort of PM cases.

Retinal vessel wall imaging using fluorescein angiography and adaptive optics imaging in acute branch retinal artery occlusion.

PURPOSE: To report the retinal vessel wall changes in a patient with acute branch retinal artery occlusion with fundus fluorescein angiography and adaptive optics imaging. METHODS: Retrospective, observational case. CASE DESCRIPTION: A 49-year-old female with cardiac ailment complained of sudden onset superior field loss for 4 days in her right eye. Her presenting visual acuity in the right eye was 20/20, N6. She was diagnosed with right eye infero-temporal branch retinal artery occlusion. A golden-yellow, round coloured embolus was noted on clinical examination obstructing the temporal division of the inferior branch of central retinal artery. Patient underwent ocular massage, anterior chamber paracentesis and oral Acetazolamide (Tab. Diamox 250 mg QID) medications. Vessel wall changes were noted using fluorescein angiography and adaptive optics retinal imaging at presentation and 10-day follow-up visit. CONCLUSION: This case highlights the importance of multimodal retinal imaging like fluorescein angiography and adaptive optics imaging in identifying and understanding the retinal vessel wall changes in the occluded vascular segment of the retina.

Peripheral and macular polypoidal choroidal vasculopathy: A retrospective comparative case series.

PURPOSE: To compare clinical and imaging features and treatment outcomes between eyes having peripheral polypoidal choroidal vasculopathy (PCV) and macular PCV. METHODS: In this retrospective comparative case series, confirmed cases of peripheral and macular PCV cases on indocyanine green angiography (ICGA) were included. The various demographic features, imaging characteristics and clinical course between cases with peripheral and macular PCV were compared and analysed. RESULTS: Fifteen eyes of 12 patients and 22 eyes of 20 patients were diagnosed with peripheral PCV and macular PCV respectively based on polyps seen on ICGA. Mean age at presentation in peripheral and macular PCV groups were 76.3 ± 8.78 and 69.1 ± 8.64 years respectively (p = 0.038). Mean logMAR visual acuity in the peripheral and macular PCV group was 0.423 ± 0.568 and 0.535 ± 0.513 respectively (p = 0.595). Peripheral subretinal hemorrhage was noted commonly in the peripheral PCV group (n = 10, 66%) and hard exudates were common in the macular PCV (19, 86%) group. Subfoveal choroid was significantly thinner in peripheral PCV group compared to macular PCV group (215.2 ± 39.94 vs 283.3 ± 50.08; p = 0.001). At final follow-up visit, 50% eyes (n = 11) in macular PCV group were still active and 87% (n = 13) eyes in the peripheral PCV showed an inactive disease (p = 0.035). CONCLUSION: Peripheral and macular PCV cases are two separate clinical entities having distinct pathogenesis, clinical and imaging features and treatment outcomes. Further studies are needed for understanding the pathomechanism in these distinct disease entities.

Bacillary Layer Detachment in Unilateral Acute Idiopathic Maculopathy: A Report of 2 Cases.

AIM: To report the presence of bacillary layer detachment (BLD) in unilateral acute idiopathic maculopathy (UAIM). CASE DESCRIPTION: Two patients diagnosed with UAIM based on the clinical and imaging features showed the characteristic splitting of the ellipsoid layer on spectral domain optical coherence tomography (SDOCT). This has been termed as bacillary layer detachment. RESULTS: No treatment was given. In both cases, there was a complete spontaneous resolution of the SDOCT findings 14-days post-presentation in Case 1 and 5-days post-presentation in Case 2 with improvement in visual acuity to 20/20, N6 in both cases. CONCLUSION: BLD in UAIM is not a commonly reported SDOCT finding and can serve as an imaging biomarker.

Sequential retinal pigment epithelium tears following intravitreal Ranibizumab injections for age-related macular degeneration.

PURPOSE: To report a case of sequential retinal pigment epithelium (RPE) tears following intravitreal Ranibizumab injections for neovascular age-related macular degeneration (AMD). METHODS: Retrospective, observational case. CASE DESCRIPTION: A 75-year-old hypertensive male was diagnosed with active neovascular AMD and pre-existing RPE tear in the left eye. His presenting best-corrected visual acuity was counting finger @ 1 metre,

Unilateral Acute Idiopathic Maculopathy following Severe Acute Respiratory Syndrome Corona Virus (SARS-CoV-2) Infection.

AIM: To report a case of unilateral acute idiopathic maculopathy (UAIM) following SARS-CoV-2 virus infection. CASE DESCRIPTION: A 44-year-old male patient, infected with SARS-CoV-2 virus previously, presented to the retina department with complaints of sudden blurring of vision in right eye. His presenting visual acuity in right eye was 20/30, N8. Fundus showed an irregular area of yellowish-white subretinal lesion at the macula involving the fovea with reddish-brown pigment clumps. Retinal imaging findings were consistent with the diagnosis of UAIM. No treatment was given. RESULTS: The imaging findings showed improvement at day 7 post-presentation with improvement in vision to 20/20, N6. At final visit (5-week post presentation), visual acuity was maintained at 20/20, N6 and there was no recurrence of findings. EXPERT OPINION: Unilateral acute idiopathic maculopathy might be associated with SARS-CoV-2 virus infection. CONCLUSION: Infection with SARS-CoV-2 virus might be associated with UAIM. Such an association has not yet been described in the literature.

Characteristics of retinal pigment clumps in Type 2 macular telangiectasia (MacTel).

OBJECTIVE: To assess the relationship of retinal pigment clump (RPC) size and its location with visual acuity and retinal neovascularisation in eyes with type 2 macular telangiectasia (MacTel). METHODS: In this cross-sectional study, eyes diagnosed with type 2 MacTel showing RPC were included. Area occupied by pigment was measured on the multicolour image using the area tool on the Spectralis, Heidelberg machine. Pigment location within retinal layers was noted with OCT. Analysis was performed to identify factors associated with poor vision and proliferative disease. RESULTS: Sixty-two eyes of 42 patients diagnosed with type 2 MacTel and RPC were included. The mean age was 64.31 ± 10.19 years. There were 13 (31%) males and 29 (69%) females in the study. 74% of patients were diabetics and the mean logMAR visual acuity of the participants was 0.619 ± 0.359. Univariate and multivariate binary logistic regression analysis identified female gender (p = 0.026), increasing RPC size (p = 0.008) and its presence above the outer plexiform layer (p = 0.006) to be associated with poor vision and proliferative disease in type 2 MacTel. CONCLUSION: Our data identified female gender, larger pigment size and its location above the OPL to be associated with poor vision and proliferative disease. This data may be useful for further improving the current system for staging disease severity in type 2 MacTel.

Retinal arcades in posterior microphthalmos: biometric correlation.

CLINICAL RELEVANCE: Posterior microphthalmos (PM) is a rare developmental disorder characterised by high hyperopia, short axial length, presence of retinal papillomacular fold and relatively normal anterior segment findings. BACKGROUND: The purpose of the study was to compare the retinal arcade distance from fovea between PM cases and to correlate axial shortening in PM eyes with imaging findings. METHODS: This retrospective, comparative case series included 24 eyes of 12 patients with PM as cases and an equal number of age- and sex-matched controls. Retinal findings on optical coherence tomography (OCT), OCT-angiography, Multicolour® image, axial length and corneal biometry were computed, compared and correlated between two groups. RESULTS: Retinal papillomacular fold was noted in all 24 PM eyes. Retinal arcade narrowing was noted in PM (p < 0.001). The central retina (p < 0.001) and choroid (p = 0.003) was thick in PM. Corneal biometry showed shorter axial length (p < 0.001), high keratometry readings (p < 0.001) and small corneal diameters (p = 0.011) in PM. Vessel density (p = 0.031) on OCTA was denser and foveal avascular zone area (p = 0.033) reduced in PM. Strong negative correlation of axial length with spherical equivalent (r = > -0.804;p < 0.001), vessel density (r = > -0.803; p = <0.001) and K1 (r = > -0.76; p < 0.001) and K2 (r = > -0.67; p = 0.001) keratometry readings was noted in PM. Significant positive correlation was noted between axial length and anterior chamber depth (r = 0.75; p < 0.001), foveal avascular zone area (r = 0.56; p = 0.033) and corneal diameter (r = 0.65; p = 0.001). Vessel density on OCT-angiography correlated positively with central corneal thickness (r = 0.552;p = 0.005) and corneal powers K1 (r = 0.709; p = 0.001) and K2 (r = 0.56; p = 0.004) and negatively with corneal diameter (r = > -0.521; p = 0.033). CONCLUSION: Increased choroidal thickening and retinal vascular arcade narrowing were two important, interesting observations noted with PM. Intercorrelation between the axial length, OCT, OCT-angiography and corneal biometry helped in understanding the pathogenesis and the structural and vascular changes in PM eyes.

Onion ring sign on spectral domain optical coherence tomography in diabetic macular edema: Its evolution and outcomes.

PURPOSE: To report evolution and outcomes of hyperreflective crystalline deposit (HCD) on optical coherence tomography (OCT) in diabetic maculopathy (DM). METHODS: Patients with DM showing HCD on OCT for the first time between June 2017 and May 2021 were included in the study. Demographic, ophthalmic and OCT features were documented and analysed. Factors leading to the development of HCD and its effect on the functional outcome were analysed and described in this study. RESULTS: Sixty cases of HCD were identified in 45 (males -33; females - 12) patients for the first-time during the defined study period. Mean age of the eligible patients was 61.53 ± 8.19 years. Average duration of diabetes was 13.82 ± 7.38 years. Mean visual acuity of these patients was 0.902 ± 0.438 logMAR units (Snellen equivalent = 20/160). Patients with HCD showed subretinal hard exudates, were on anti-cholesterol medications (n = 36, 80%) and showed reduced visual acuity (20/160) if the HCD involved the fovea. The median time taken for the development of HCD was 28 months. Mean follow-up duration of the study was 26.19 ± 27.98 months. Persistence of HCD in all cases (n = 42, 100%) was noted at the last follow-up visit. CONCLUSION: Horizontal, single or multi-layered HCDs on OCT in DM represent intraretinal or subretinal cholesterol crystal precipitates evolving from the hard exudates identical to the "onion ring sign" seen in neovascular AMD. HCDs or CCs depict deranged lipid metabolism, chronic vascular leakage and can lead to substantial visual impairment if the fovea gets involved.