IMPAIRMENTS IN CONE PIGMENT REGENERATION AND ABSOLUTE THRESHOLD IN MACULAR TELANGIECTASIA TYPE 2.

PURPOSE: To test the hypothesis that Müller cell dysfunction in macular telangiectasia type 2 (MacTel) results in delayed cone adaptation kinetics and to assess absolute cone and rod thresholds in this condition. METHODS: Adaptation after an approximate 63.5% full-field cone photopigment bleach was assessed for Goldmann size V (1.7° diameter) 640 nm (red) and 480 nm (blue) targets presented at a retinal locus corresponding to 2° temporal to fixation. The cone time constant of adaptation and absolute cone and rod thresholds were calculated from exponential functions fitted to the resultant dark adaptation curves. RESULTS: Eighteen eyes with MacTel (from 11 patients) were compared with 19 control eyes (from 16 normal subjects). Cone adaptation kinetics were significantly impaired in MacTel, as was the absolute cone threshold. Final thresholds for blue targets were also significantly elevated in MacTel, consistent with impaired rod absolute threshold. Losses in sensitivity observed in MacTel were consistent with a so-called d1/2 mechanism (i.e., receptoral) site of sensitivity loss. CONCLUSION: In addition to previously documented impairments in rod dark adaptation, MacTel results in a significant elevation in cone thresholds because of pathology at the level of the photoreceptors. The delays in cone adaptation that we found in eyes with MacTel may reflect impairment of the Müller cell-mediated cone-specific visual cycle.

LONGITUDINAL FLUORESCENCE LIFETIME IMAGING OPHTHALMOSCOPY ANALYSIS IN PATIENTS WITH MACULAR TELANGIECTASIA TYPE 2 (MacTel).

PURPOSE: Fluorescence lifetime imaging ophthalmoscopy (FLIO) shows characteristic patterns in macular telangiectasia Type 2 (MacTel). This study investigates FLIO changes over time to better understand disease progression. METHODS: Thirty-three patients with MacTel (age 60 ± 15 years) were followed at the Moran Eye Center with a prototype Heidelberg Engineering FLIO. The mean follow-up time was 19 ± 8 months (range 6-34 months). Fundus autofluorescence was excited at 473 nm, and FLIO lifetimes were recorded in in short (498-560 nm) and long (560-720 nm) spectral wavelengths channels. RESULTS: Autofluorescence lifetimes imaging ophthalmoscopy lifetimes from the MacTel area prolonged significantly over time (subfield T1, baseline: short spectral channel 210 ± 54 ps, long spectral channel 269 ± 58 ps; follow-up: short spectral channel 225 ± 59 ps, P < 0.001, long spectral channel 282 ± 64 ps, P < 0.01). The average 12-months prolongation of FLIO lifetimes was 9 ps (short spectral channel) and 8 ps (long spectral channel). Autofluorescence lifetimes changes correlated positively with ellipsoid zone loss and negatively with changes in retinal thickness. CONCLUSION: Autofluorescence lifetimes in MacTel slowly prolong over time, and temporal patterns progress to full rings. Detailed knowledge about FLIO changes will aid in understanding disease development and progression.

Functional Relevance of Hyper-Reflectivity in Macular Telangiectasia Type 2.

Purpose: The purpose of this study was to quantify hyper-reflective lesions on en face optical coherence tomography (OCT) and study its functional relevance in macular telangiectasia type 2 (MacTel). Design: This was a retrospective, cross-sectional cohort study. Methods: Baseline image and functional data from participants of a phase II clinical trial (NCT01949324) that studied the effect of Ciliary Neurotrophic Factor in patients with MacTel were analyzed. The projection of hyper-reflectivity within different layers on OCT was used to generate an en face view and measure the en face size of hyper-reflectivity. Ellipsoid zone (EZ)-loss was additionally evaluated, and en face images were superimposed onto microperimetry sensitivity maps, allowing to estimate mean retinal sensitivity within areas displaying hyper-reflectivity and EZ-loss, respectively. Best-corrected visual acuity (BCVA) and reading speed were also analyzed. Results: Fifty-two eyes from 52 patients were analyzed. Hyper-reflectivity was present in 32 eyes (62%), and EZ-loss in 50 (96%) eyes. Mean lesion size was 0.11 mm² (range = 0.01-0.26) for hyper-reflectivity and 0.51 mm² (range = 0.02-1.34) for EZ-loss, and lesion sizes correlated strongly (Spearman r = 0.79, P < 0.001). Although both hyper-reflectivity and EZ-loss were associated with a significant decrease in retinal sensitivity, mean sensitivity thresholds differed significantly between lesions (0.9 dB vs. 16.3 dB; P < 0.001), indicating an almost complete loss of sensitivity in hyper-reflective areas. No correlations were found between the size of hyper-reflectivity and BCVA (r = 0.09) or reading speed (r = -0.17). Conclusions: En face OCT can be used to quantify the area of hyper-reflective lesions in MacTel. Hyper-reflectivity in MacTel is associated with severe functional impairment, leading to an almost complete loss of retinal sensitivity as observed on microperimetry.

HYPERREFLECTIVITY ON OPTICAL COHERENCE TOMOGRAPHY IN MACULAR TELANGIECTASIA TYPE 2.

PURPOSE: To define, characterize, and classify hyperreflectivity on optical coherence tomography and report its prevalence in macular telangiectasia Type 2. METHODS: In a primary cross-sectional analysis, multimodal imaging data were retrospectively analyzed. The definition of hyperreflectivity and neovascularization on optical coherence tomography followed optical coherence tomography angiography-based criteria. Eyes were graded for the presence of hyperreflectivity and neovascularization and further categorized into three classes based on position and extent of hyperreflectivity. In a secondary analysis, eyes were reviewed for ≥24 months using optical coherence tomography imaging. RESULTS: Three hundred and twenty-two eyes from 161 patients were analyzed in the cross-sectional analysis. Hyperreflectivity was found in 177 (55%) and neovascular membranes in 49 (15%) eyes. Hyperreflectivity correlated significantly with parameters indicative of disease progression. In the longitudinal analysis, 206 eyes from 103 patients were reviewed over a mean of 35.6 months. 17/86 eyes (20%) showed a de novo development of hyperreflectivity. 8/29 eyes (28%) with preexistent intraretinal hyperreflectivity developed outer retinal hyperreflectivity. A high proportion of eyes with outer retinal hyperreflectivity (17/52 [33%]) developed neovascular membranes. CONCLUSION: Hyperreflectivity represents a common finding in macular telangiectasia Type 2 but lacks a uniform definition. We propose a hyperreflectivity grading scale that may help to estimate disease progression and identify eyes at risk for developing neovascular membranes.

Prevalence and Severity of Diabetic Retinopathy in Patients with Macular Telangiectasia Type 2.

PURPOSE: To study the prevalence and severity of diabetic retinopathy (DR) in patients with macular telangiectasia type 2 (MacTel 2). DESIGN: Retrospective case series. PARTICIPANTS: Patients with a diagnosis of MacTel 2 treated at the Rotterdam Eye Hospital or Erasmus Medical Center between 2014 and 2018 were included. METHODS: The following information was retrieved from patient files: demographics, history of diabetes mellitus and hypertension, presence of DR, and severity of DR, that is, mild, moderate, severe, or proliferative. Presence of diabetic macular edema (DME) was assessed using OCT. MAIN OUTCOME MEASURES: Presence and severity of DR. RESULTS: Two hundred six eyes of 103 patients were included. At the onset of MacTel 2, the mean age was 61 years (standard deviation [SD], 9.8 years) and 64 (62%) were women. Mean follow-up was 71 months (SD, 60 months). Diabetes mellitus type 2 was present in 50 patients (49%) and hypertension was present in 47 patients (46%). Mild DR was present in 22 eyes (11%), of which 14 eyes (7%) showed signs at baseline and 8 eyes (4%) showed signs at a later time during follow-up. Ten eyes (5%) demonstrated remission of mild DR during follow-up. Both eyes (1%) in 1 patient progressed to moderate DR. Severe DR, proliferative DR, and DME did not occur. CONCLUSIONS: Although diabetes mellitus was highly prevalent among MacTel 2 patients, no patients showed severe or proliferative DR or DME. These findings suggest that MacTel 2 could have a protective effect on the progression of DR. We hypothesize that our results may be explained by the role of Müller cells in the development of MacTel 2 and DR, and therefore a link between both diseases warrants additional studies.

Retinal cavitations in macular telangiectasia type 2 (MacTel): longitudinal structure-function correlations.

BACKGROUND/AIMS: To quantify retinal cavitation size over time in macular telangiectasia type 2 (MacTel) and to correlate changes with visual acuity and area of ellipsoid zone loss. METHODS: Optical coherence tomography (OCT) macula volume scans from sham eyes included in a prospective, phase II clinical trial of human ciliary neutrophic factor for MacTel at baseline, 1 year and 2 years of follow-up were analysed. Cavitations were segmented by two independent readers. Total cavitation volume was compared with area of ellipsoid zone loss and best-corrected visual acuity (BCVA). RESULTS: Fifty-one eyes from 51 unique patients (mean age 62 years, range 45-79 years) were included. Intraclass correlation between readers for cavitation volume was excellent (>0.99). Average cavitation volume was 0.0109 mm3, 0.0113 mm3 and 0.0124 mm3 at baseline, 1 year and 2 years, respectively. The average rate of cavitation volume change was +0.0039 mm3/year. 10 eyes (20%) had a significant change in cavitation volume during the study (3 decreased, 7 increased). Eyes with increased cavitation volume had worse BCVA compared with eyes with no change/decreased cavitation volume (71.5 vs 76.1 ETDRS letters, respectively). Cavitation volume was negatively correlated to BCVA (r=-0.37) but not to area of ellipsoid zone loss. Cavitation volume was negatively predictive of BCVA in both univariate and multivariate mixed-effects modelling with ellipsoid zone loss. CONCLUSIONS: Retinal cavitations and their rate of change in MacTel can be reliably quantified using OCT. Cavitations are negatively correlated with visual acuity and may be a useful OCT-based biomarker for disease progression and visual function in MacTel.

STELLATE NONHEREDITARY IDIOPATHIC FOVEOMACULAR RETINOSCHISIS IN A PATIENT WITH MACULAR TELANGIECTASIA TYPE 2.

PURPOSE: To present a case of unilateral stellate nonhereditary idiopathic foveomacular retinoschisis in a patient with macular telangiectasia (MacTel) Type 2. METHODS: Single-patient case report. RESULTS: A 61-year-old female white patient was referred to our clinic with metamorphopsia and reduction of visual acuity over a period of 2 months on her right eye. Ocular findings in her right eye included reduced best-corrected visual acuity of 20/63 Snellen, foveomacular retinoschisis with extension to the lower middle periphery, central elevation of the neurosensory retina, and macular telangiectasia (MacTel) Type 2. Other causes of foveomacular retinoschisis, such as glaucoma, myopic degeneration, optic or scleral pit, X-linked juvenile retinoschisis, degenerative retinoschisis, and vitreomacular traction, were ruled out. The patient had no history of niacin or taxane medication, which may cause rather similar appearing cases of cystoid macular edema without leakage in fluorescein angiography. Because of the unilateral presentation, uneventful medical history, female sex, and the absence of known hereditary diseases or retinal pathologies in the patient's family history, hereditary predisposition appears to be highly unlikely. CONCLUSION: To our knowledge, this is the first reported case of stellate nonhereditary idiopathic foveomacular retinoschisis in combination with MacTel Type 2. Whether or not MacTel Type 2 plays a role in the development of stellate nonhereditary idiopathic foveomacular retinoschisis or has an impact on its clinical course requires further investigation. Furthermore, we suggest a significant involvement of Henle fiber layer in the process of intraretinal expansion in optical coherence tomography, in accordance with the most recent published nomenclature.

Right-angled vessels in macular telangiectasia type 2.

PURPOSE: To evaluate the role of right-angled vessels (RAVs) during disease progression in macular telangiectasia type 2 (MacTel). METHODS: In this study, 100 eyes of 52 patients and 52 eyes of 26 age-related controls were examined using fundus photography, spectral-domain optical coherence tomography (SD-OCT), OCT angiography (OCT-A) and fundus fluorescein angiography (FFA). Two masked readers graded fundus photographs of patients' eyes into five disease stages according to Gass and Blodi, and evaluated all eyes for the presence of RAVs. If RAVs were present, their course and origin (arterial vs venous) was evaluated with OCT-A and FFA, respectively. Additionally, we looked for morphological correlates of these vessels on SD-OCT scans. Neovascular eyes were analysed for the presence of RAVs and for morphological changes on formation of neovascularisations (NVs). RESULTS: In OCT-A, RAVs were already detectable in eyes with early stages (1 to 2), could be tracked from superficial to outer retinal layers and were shown to form anastomoses in the outer retina with disease progression. These vessels were of both arterial and venous origin as shown by early phase FFA. Dilated capillaries and RAVs in OCT-A corresponded to hyper-reflective alterations of the outer retina on SD-OCT scans. In 19/19 eyes, NVs were associated with the presence of RAVs, and RAVs were shown to directly connect to neovascular complexes and to undergo morphological changes upon NV formation. CONCLUSIONS: The results emphasise the role of RAVs during disease progression from an early stage on and demonstrate their involvement in the development of secondary NVs in MacTel.

FUNCTIONAL AND STRUCTURAL EFFECTS OF NONDAMAGING RETINAL LASER THERAPY FOR MACULAR TELANGIECTASIA TYPE 2: A Randomized Sham-Controlled Clinical Trial.

PURPOSE: Macular telangiectasia (MacTel) Type 2 is a progressing neurovascular disease of the macula, currently lacking effective treatment. This study assessed the effect of nondamaging retinal laser therapy (NRT) compared with sham. METHODS: Twelve MacTel patients were enrolled in this double-masked, controlled, randomized clinical trial. For the nine patients with both eyes eligible, one eye was randomized to NRT or sham and the other received alternate treatment. For three patients with only one eye eligible, that eye was randomly assigned either NRT or sham. Ellipsoid zone disruption, best-corrected visual acuity, and macular automated perimetry at 12 months served as structural and functional measures. RESULTS: Eleven eyes were randomized to sham and 10 to NRT. Baseline best-corrected visual acuity was 66 letters (20/50) for sham and 72 letters (20/40) for NRT (P = 0.245). Ellipsoid zone disruption area was 298 µm2 in sham and 368 µm2 in NRT (P = 0.391). At 12 months, ellipsoid zone disruption increased by 24% in sham and decreased by 34% in NRT (P < 0.001). Best-corrected visual acuity measures remained stable during follow-up compared with baseline. At 1 year, the mean macular sensitivity was 28 dB in the NRT group, compared with 26 dB in sham. CONCLUSION: Nondamaging retinal laser therapy was safe and well tolerated in patients with MacTel and resulted in structural and functional improvements, which could represent a protective effect of laser-induced hyperthermia. Longer follow-up and larger number of patients should help corroborate these effects.

Optical coherence tomographic features of macular telangiectasia type 2: Korean Macular Telangiectasia Type 2 Study-Report No. 1.

We analysed the imaging findings of macular telangiectasia (MacTel) type 2 in Korea using spectral domain optical coherence tomography (SD-OCT) and investigated their relationship with visual acuity and clinical stages. A retrospective multicentre cross-sectional study was conducted in six tertiary hospitals in Korea and included 129 patients. We analysed all the SD-OCT images encompassing the macular area. Hyporeflective cavities (77.7%) were the most frequently detected abnormalities in SD-OCT. Disruption of the external limiting membrane, ellipsoid zone, and interdigitation zone were found in 67 (40.4%), 87 (52.4%), and 94 eyes (56.6%), respectively. Four eyes (2.4%) had lamellar macular hole, and five eyes (3.0%) full-thickness macular hole. Neovascularisation, either subretinal or intraretinal, was found in 14 eyes (8.4%). Eyes with outer retinal hyperreflective band disruption had lower visual acuity than those without them. The presented characteristic clinical features of OCT in MacTel type 2 can not only aid in differentiating this disease from others but are also helpful for better judgement of the disease stage in daily clinical practice. Inner retinal hyporeflective cavities without outer retinal abnormalities on SD-OCT, although classified as severity scale 3, could be considered a relatively early stage in the disease process in terms of vision.

Macular Telangiectasia Type 2: Visual Acuity, Disease End Stage, and the MacTel Area: MacTel Project Report Number 8.

PURPOSE: To report the visual acuity measures from the macular telangiectasia type 2 (MacTel) registry and to investigate and describe phenotypic findings in eyes with substantial vision loss resulting from MacTel. DESIGN: Cross-sectional multicenter study. PARTICIPANTS: Participants in the MacTel Natural History Observation Registration Study. METHODS: Best-corrected visual acuity (BCVA) data, retinal imaging data, and clinical data were accessed from the MacTel Study databases in May 2019. MAIN OUTCOME MEASURES: Frequency distribution of BCVA and its relationship to age; morphologic changes in eyes with very late disease stages, defined by a BCVA of 20/200 or worse; average retinal thickness of macular subfields on OCT; and dimensions of the area affected by MacTel (i.e., the MacTel area). RESULTS: Best-corrected visual acuity was 20/50 or worse in 37.3% and 20/200 or worse in 3.8% of 4449 eyes of 2248 patients; 18.4% and 0.7% of all patients showed bilateral BCVA of 20/50 or worse and 20/200 or worse, respectively. Asymmetry between right and left eyes was present (median BCVA, 71 letters vs. 74 letters), a finding supported by more advanced morphologic changes in right eyes. Participant age correlated with BCVA, but the effect size was small. If a neovascularization or macular hole were present, bilateral occurrence was frequent (33% or 17%, respectively), and BCVA was better than 20/200 (79% or 78%, respectively) or 20/50 or better (26% or 13%, respectively). Eyes with advanced disease (BCVA, ≤20/200) showed the following characteristics: (1) atrophy of the foveal photoreceptor layer with or without associated subretinal fibrosis; (2) an affected area, termed MacTel area, limited to a horizontal diameter not exceeding the distance between the temporal optic disc margin and foveal center, and the vertical diameter not exceeding approximately 0.8 times this distance (exceptions were eyes with large active or inactive neovascular membranes); (3) reduced retinal thickness measures within the MacTel area; and (4) less frequent retinal greying and more frequent hyperpigmentations compared with eyes that have better BCVA. CONCLUSIONS: Severe vision loss is rare in MacTel and is related to photoreceptor atrophy in most people. Results indicate disease asymmetry with slightly worse vision and more advanced disease manifestation in right eyes. MacTel-related neurodegeneration does not spread beyond the limits of the MacTel area.

Refractory adult Coats disease treated with dexamethasone intravitreal implant: A case report.

INTRODUCTION: Coats disease is a sporadic, retinal vascular abnormality, causing blindness. Several interventional methods, including laser photocoagulation, have been proposed; however, the use of intravitreal dexamethasone in refractory Coats disease is not well described. PATIENT CONCERNS: A 38-year-old man presented with a painless reduction in visual acuity in his right eye, commencing 15 days prior to initial assessment. DIAGNOSIS: Clinical manifestations and multimodal imaging indicated Coats disease. INTERVENTIONS: Retinal laser photocoagulation was performed in the nonperfused areas, 15 months later, the exudative retinal detachment, and macular edema remained, the patient was then treated with an intravitreal slow-release dexamethasone implant. OUTCOMES: The exudative retinal detachment and macular edema had resolved, and the BCVA had also improved. CONCLUSION: Dexamethasone intravitreal implantation was effective in treating refractory Coats disease.

Beyond Performance Metrics: Automatic Deep Learning Retinal OCT Analysis Reproduces Clinical Trial Outcome.

PURPOSE: To validate the efficacy of a fully automatic, deep learning-based segmentation algorithm beyond conventional performance metrics by measuring the primary outcome of a clinical trial for macular telangiectasia type 2 (MacTel2). DESIGN: Evaluation of diagnostic test or technology. PARTICIPANTS: A total of 92 eyes from 62 participants with MacTel2 from a phase 2 clinical trial (NCT01949324) randomized to 1 of 2 treatment groups METHODS: The ellipsoid zone (EZ) defect areas were measured on spectral domain OCT images of each eye at 2 time points (baseline and month 24) by a fully automatic, deep learning-based segmentation algorithm. The change in EZ defect area from baseline to month 24 was calculated and analyzed according to the clinical trial protocol. MAIN OUTCOME MEASURE: Difference in the change in EZ defect area from baseline to month 24 between the 2 treatment groups. RESULTS: The difference in the change in EZ defect area from baseline to month 24 between the 2 treatment groups measured by the fully automatic segmentation algorithm was 0.072±0.035 mm2 (P = 0.021). This was comparable to the outcome of the clinical trial using semiautomatic measurements by expert readers, 0.065±0.033 mm2 (P = 0.025). CONCLUSIONS: The fully automatic segmentation algorithm was as accurate as semiautomatic expert segmentation to assess EZ defect areas and was able to reliably reproduce the statistically significant primary outcome measure of the clinical trial. This approach, to validate the performance of an automatic segmentation algorithm on the primary clinical trial end point, provides a robust gauge of its clinical applicability.

OCTA characterisation of microvascular retinal alterations in patients with central serous chorioretinopathy.

PURPOSE: This study aimed to describe the characteristics of microvascular retinal alterations in eyes with chronic central serous chorioretinopathy (CSC) employing optical coherence tomography angiography (OCTA) analysis. METHODS: We collected data from 472 eyes with chronic CSC from 336 patients who had OCTA obtained. Each OCTA image was graded by two readers to assess the presence of microvascular retinal alterations, including regions of vascular rarefaction/retinal hypoperfusion, enlargement of the foveal avascular zone (FAZ) and presence of telangiectasias or microaneurysms. Volume spectral domain optical coherence tomography (SD-OCT) scans were obtained through the macula and the OCT was correlated with the OCTA findings in eyes with retinal vascular alterations. RESULTS: OCTA displayed microvascular retinal alterations in 18 out of 474 eyes (3.6%) from 14 patients (13 male and 1 female; mean±SD age was 54.7±11.1 years). One eye displayed the presence of retinal telangiectasias, while 17 out of 18 eyes were graded as having areas of retinal vascular rarefactions, and 3 out of 17 eyes were also characterised by an enlargement of the FAZ. The parafoveal region was the location most involved by retinal vascular changes (66,7%), followed by foveal (22,2%) and perifoveal (11.1%) regions, respectively. CONCLUSION: Although CSC is known to represent a choroidal disorder, retinal vascular alterations may be present in these eyes and OCTA may represent a useful tool to identify and describe them.

Multifocal electroretinography in patients with macular telangiectasia type 2.

PURPOSE: To evaluate the multifocal electroretinographic (mfERG) response in patients with macular telangiectasia (MacTel) type 2. METHODS: Prospective, observational case series. Thirty-four eyes of 18 patients diagnosed with nonproliferative MacTel type 2 underwent recording of best-corrected visual acuity (BCVA), fundus fluorescein angiography, spectral domain optical coherence tomography (SD-OCT) and mfERG using 61 hexagonal elements, in accordance with ISCEV guidelines. The P1 average response densities and implicit times of the first-order kernel responses were grouped into five concentric rings centred on the fovea. Data from the left eyes of cases (18 eyes) were compared with 34 eyes of age- and sex-matched controls. Correlation analyses were performed between BCVA, mfERG parameters and SD-OCT measurements. RESULTS: Mean BCVA of the cases was 0.3 ± 0.26 ranging from 0 to 1. On SD-OCT, mean central foveal thickness was 205.78 ± 40.92 µm and average mean macular thickness was 248.22 ± 23.08 µm. Mean P1 amplitudes were significantly decreased in eyes with MacTel type 2 as compared to controls in ring 1 (p = 0.039). Mean P1 implicit time in all the rings was comparable between the two groups. BCVA was significantly and negatively correlated with P1 amplitude in ring 1 (r = - 0.518, p = 0.028) in eyes with MacTel type 2. CONCLUSION: mfERG reflects localised inner retinal dysfunction in MacTel type 2. Correlation with BCVA reinforces that mfERG should be used to objectively assess the macular function in these patients.

FLUORESCENCE LIFETIME PATTERNS IN MACULAR TELANGIECTASIA TYPE 2.

PURPOSE: Type 2 idiopathic macular telangiectasia (MacTel) is a rare bilateral neurodegenerative disease characterized by alterations in the macular capillary network leading to central vision loss. The purpose of this study was to quantify disease-specific retinal fluorescence lifetime patterns in patients with MacTel using fluorescence lifetime imaging ophthalmoscopy. PARTICIPANTS: Both eyes of 14 patients (mean age ± SEM, 67.8 ± 6.4 years) with a clinical diagnosis of MacTel Type 2 and 14 healthy age-matched controls (age 69.8 ± 6.4 years) were included in this study. METHODS: All participants were imaged with a fluorescence lifetime imaging ophthalmoscope (Heidelberg Engineering, Germany). Mean retinal fluorescence lifetimes (Tm) were obtained in the short spectral channels (498-560 nm) and long spectral channels (560-720 nm). Clinical features, fundus images, fundus autofluorescence intensity images, spectral domain optical coherence tomography, and corresponding macular pigment optical density measurements using a modified confocal scanning laser ophthalmoscope (mpHRA) were further analyzed. Patients were classified into five phenotypic subgroups using the Gass and Blodi classification. RESULTS: Mean fluorescence lifetimes were significantly prolonged temporal to the fovea in patients with MacTel compared with healthy controls (mean ± SEM: short spectral channels 543 ± 61 ps vs. 304 ± 9 ps; P < 0.0001; long spectral channels: 447 ± 26 ps vs. 348 ± 11 ps; P < 0.0001), and appeared as a crescent or ring-shaped pattern. Prolonged lifetime patterns correlated with decreased macular pigment density on macular pigment optical density measurements. Follow-up examinations were performed in four MacTel patients, which revealed an increase of short spectral channel Tm of 22% over 2.1 years in the temporal fovea. CONCLUSION: This study confirms that fundus autofluorescence lifetimes display characteristic patterns in patients with MacTel Type 2 disease and provide information about macular pigment and possibly photoreceptor loss. Fluorescence lifetime prolongation correlates with disease severity and may therefore be a useful addition to other imaging modalities for assessing disease progression in MacTel Type 2.

Visual acuity outcomes in Coats disease by classification stage in 160 patients.

PURPOSE: To assess visual outcomes of Coats disease by classification stage. METHODS: A retrospective review was conducted on consecutive patients with Coats disease, classified according to Shields classification and with available Snellen visual acuity before and after treatment. RESULTS: There were 160 eyes with Coats disease (stage 1 (n=2) vs stage 2A (n=17) vs stage 2B (n=22) vs stage 3A1 (n=26) vs stage 3A2 (n=40) vs stage 3B (n=42) vs stage 4 (n=9) vs stage 5 (n=2)). By comparison, more advanced stage showed greater frequency of poor presenting visual acuity (<20/200) (0% vs 0% vs 50% vs 35% vs 38% vs 83% vs 100% vs 100%, p<0.001) and higher mean intraocular pressure (17 vs 15 vs 15 vs 15 vs 15 vs 15 vs 37 vs 26, p<0.001). More advanced stage was less likely managed with laser photocoagulation (100% vs 87% vs 48% vs 62% vs 74% vs 35% vs 0% vs 0%, p<0.001) and more likely with cryotherapy (0% vs 47% vs 81% vs 81% vs 82% vs 88% vs 50% vs 100%, p=0.001). More advanced stage was associated with lower frequency of visual acuity ≥20/40 (100% vs 71% vs 5% vs 42% vs 23% vs 5% vs 0% vs 0%, p<0.001) and greater frequency of visual acuity <20/200 (0% vs 12% vs 36% vs31 % vs 45% vs 88% vs 0% vs 100%, p<0.001). CONCLUSION: Visual acuity in eyes with Coats disease parallels staging with more advanced stage demonstrating poorer visual acuity at presentation and final visit.

Non-proliferative type II macular telangiectasia variant with subfoveal detachment: role of anti-VEGF therapy.

AIMS: To describe a rare variant of non-proliferative stage of type II macular telangiectasia (MacTel2) with the presence of subfoveal detachment (SFD) and its response to intravitreal antivascular endothelial growth factor (VEGF) therapy. METHODS: A retrospective case series of patients diagnosed with a rare variant of non-proliferative MacTel2 (defined as MacTel2 with the presence of SFD on optical coherence tomography (OCT) in the absence of subretinal neovascularisation, confirmed on fluorescein angiography (FA)) over a period of 2 years. Patients were studied with biomicroscopy, OCT and FA. Patients were managed either with observation or anti-VEGF therapy. RESULTS: Twenty eyes of 13 patients, all female with a mean age of 52.2±6.1 years, were diagnosed with this variant of non-proliferative MacTel2. The best-corrected visual acuity at presentation ranged from 20/20 to 20/120. Six eyes were lost to follow-up. Eight eyes were kept under observation for a mean follow-up of 7.3±2.2 months and did not show resolution. Eight eyes underwent anti-VEGF therapy with a mean number of intravitreal injections of 2±1.07 per eye during a mean follow-up of 9.38±5.5 months. All eyes showed complete resolution of SFD, with a visual improvement of ≥1 line of Snellen's acuity in 87.5% of the eyes. CONCLUSION: This is the largest series of a variant of non-proliferative MacTel2 with SFD, which shows good anatomical and functional response to anti-VEGF therapy, in comparison to observation alone. Careful evaluation of the OCT images may be helpful in predicting the visual prognosis with anti-VEGF therapy.

Visual outcomes after treatment in pediatric patients with Coats' disease.

OBJECTIVE: To report visual outcomes for children with Coats' disease after treatment. DESIGN: Retrospective case series. PARTICIPANTS: Pediatric patients with Coats' disease treated between 2000 and 2018 at a tertiary care pediatric hospital. METHODS: Review of medical records. The primary outcome was visual acuity at final follow-up. Anatomical outcomes, retreatment, and risk factors for a poor outcome were also assessed. RESULTS: There were 30 patients with Coats' disease. All cases were unilateral, and 28 (93%) were male. At presentation, 14 (47%) had stage 2 disease (retinal exudates) and 16 (53%) had stage 3 disease (subtotal or total exudative retinal detachment). All patients underwent laser photocoagulation and (or) cryopexy as primary treatment, combined with antivascular endothelial growth factor injection in 7 patients, posterior sclerotomy in 5 patients, and pars plana vitrectomy in 1 patient. Retreatment was required in 16 (53%) patients. After a median follow-up of 3.8 years, visual acuity was 20/50 or better in 6 patients (20%), 20/60 to 20/150 in 3 (10%), 20/200 to counting fingers in 8 (23%), and hand motion or worse in 14 (47%). Greater severity of disease at presentation was significantly associated with a poor visual outcome (p = 0.0001). In terms of complications, 7 (23%) eyes developed cataracts and 2 (7%) progressed to phthisis bulbi, but no patients required enucleation. CONCLUSIONS: The visual prognosis for children with Coats' disease remains poor, particularly in patients with more severe disease at presentation. The risk of severe complications and enucleation is low after treatment.

Binocular Inhibition of Reading in Macular Telangiectasia Type 2.

Purpose: To assess the presence of binocular gain in macular telangiectasia type 2 (MacTel) and its correlation to paracentral scotomas. Methods: Sixty-eight patients with MacTel were consecutively recruited for a cross-sectional analysis. Best-corrected visual acuity (BCVA), reading acuity, and reading speed were tested monocularly and binocularly. Macular retinal sensitivity was examined with fundus-controlled perimetry (microperimetry). Scotomas were quantified by their size, their depth, and their proximity to the fovea. Results: Binocular reading speed and acuity were lower than monocular reading speed and acuity in the functionally better eye (142 vs. 159 words per minute and 0.43 vs. 0.28 log reading acuity determination, P < 0.001). Magnitude of binocular inhibition of reading speed was correlated to the degree of interocular functional difference (R2 = 0.61, P < 0.001). This correlation was not found for reading acuity or BCVA (R2 < 0.03). Binocular reading speed was negatively correlated to size of right and left eye scotomas, with bigger effect size for left eye scotomas. The magnitude of binocular inhibition was correlated to size of left eye scotomas, but not of right eye scotomas. When both eyes had similar scotoma characteristics, the right eye was more frequently the better reading eye. Conclusions: We provide evidence for the presence of binocular inhibition of reading performance in MacTel, likely due to binocular rivalry. This may result from the characteristic paracentral scotomas in noncorresponding retinal fields and, in particular, a disruptive projection of scotomas in reading direction arising from the left eyes. Patients may benefit from occluding one eye while reading.