Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 40
Filter
1.
medRxiv ; 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39314940

ABSTRACT

Reticular pseudodrusen (RPD) signify a critical phenotype driving vision loss in age-related macular degeneration (AMD). Their detection is paramount in the clinical management of those with AMD, yet they remain challenging to reliably identify. We thus developed a deep learning (DL) model to segment RPD from 9,800 optical coherence tomography B-scans, and this model produced RPD segmentations that had higher agreement with four retinal specialists (Dice similarity coefficient [DSC]=0·76 [95% confidence interval [CI] 0·71-0·81]) than the agreement amongst the specialists (DSC=0·68, 95% CI=0·63-0·73; p <0·001). In five external test datasets consisting of 1,017 eyes from 812 individuals, the DL model detected RPD with a similar level of performance as two retinal specialists (area-under-the-curve of 0·94 [95% CI=0·92-0·97], 0·95 [95% CI=0·92-0·97] and 0·96 [95% CI=0·94-0·98] respectively; p ≥0·32). This DL model enables the automatic detection and quantification of RPD with expert-level performance, which we have made publicly available.

2.
Acta Ophthalmol ; 101(1): e26-e42, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35790079

ABSTRACT

PURPOSE: The aim of this systematic literature review was to describe patient-reported outcomes, mental health and caregiver burden in patients with neovascular age-related macular degeneration (nAMD) treated with anti-vascular endothelial growth factor (VEGF) agents in routine clinical practice. METHODS: Electronic searches were conducted in Embase and MEDLINE according to pre-defined criteria. RESULTS: Of 856 records identified, 63 met inclusion criteria. Depression or depressive symptoms were reported in up to 42% of patients with nAMD. Of 25/63 (40%) studies evaluating quality of life (QoL) and using various tools, eight studies reported composite National Eye Institute Visual Functioning Questionnaire scores following anti-VEGF treatment. Of these, seven reported a statistically significant improvement at the earliest time point measured (Month 3-12) and approximately 50% reported sustained QoL benefits at 12 months. In studies comparing the attributed or different regimens, the most important factor from the patient's perspective was the likelihood that a particular regimen would maintain vision. There was a preference towards treat and extend, which was associated with a perceived reduction in patient and caregiver burden, compared to fixed dosing. CONCLUSIONS: A coordinated holistic approach to patient care is key to optimizing patient well-being as well as visual outcomes. Further research regarding the patient-reported impact of nAMD management outside the trial setting (particularly international longitudinal studies) is warranted. Standardization of QoL studies would assist in establishing whether sustained QoL improvement, rather than prevention of QoL decline, should be a realistic expectation of treatment of nAMD in the longer term.


Subject(s)
Macular Degeneration , Wet Macular Degeneration , Humans , Ranibizumab , Angiogenesis Inhibitors/therapeutic use , Vascular Endothelial Growth Factor A , Quality of Life , Caregiver Burden , Mental Health , Macular Degeneration/drug therapy , Visual Acuity , Patient Reported Outcome Measures , Intravitreal Injections , Wet Macular Degeneration/diagnosis , Wet Macular Degeneration/drug therapy , Treatment Outcome
3.
Ophthalmol Sci ; 2(4): 100179, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36531586

ABSTRACT

Purpose: Rhegmatogenous retinal detachment repair by intraoperative sealing of the tear without a tamponade agent should enable faster restoration of vision and resumption of normal activities. It avoids the need for further surgery in the case of silicone oil endotamponade. This study evaluated the retinal thermofusion (RTF) retinopexy method of subretinal space dehydration before photocoagulation to create an instantaneous intraoperative retina reattachment in a preclinical model. Design: Preclinical study. Participants: Twenty Dutch Belt, pigmented rabbits that underwent RTF repair after experimental retinal detachment. Methods: This ex vivo model quantified adhesion force between the retina and underlying retinal pigment epithelium and choroid after treatment of 1 retinal edge using postmortem porcine or human retina (6 × 12 mm). We compared (1) control, (2) laser photocoagulation alone, (3) dehydration alone, and (4) dehydration followed by photocoagulation (RTF). Optimized parameters for RTF were then applied in the in vivo rabbit model of retinal detachment. Animals were followed up for 14 days. Main Outcome Measures: For this ex vivo model, we measured adhesion force and related this to tissue temperature. For the in vivo study, we assessed retinal attachment using funduscopy and histologic analysis. Results: The ex vivo model showed that RTF repair produced significantly higher adhesion force than photocoagulation alone independent of dehydration method: warm (60° C) high airflow (50-70 ml/minute) or using laser wavelengths targeting water absorption peaks (1470 or 1940 nm) with coaxial low airflow (10-20 ml/minute). The latter approach produced a smaller footprint of dehydration. Application of RTF (1940-nm laser with coaxial airflow) in an in vivo retinal detachment model in rabbit eyes resulted in immediate retinal adhesion, achieving forces similar to those in the ex vivo experiments. Retinal thermofusion repair resulted in stable reattachment of the retina over the 2-week follow-up period. Conclusions: We showed that a short preliminary dehydrating laser treatment of a retinal tear margin before traditional laser photocoagulation creates an immediate intraoperative waterproof retinopexy adhesion independent of tamponade and a wound-healing response. This approach potentially will allow rapid postoperative recovery regardless of the tear location and improved vision.

4.
Am J Ophthalmol ; 244: 58-67, 2022 12.
Article in English | MEDLINE | ID: mdl-35952753

ABSTRACT

PURPOSE: To determine prevalence of probable polypoidal choroidal vasculopathy (PCV) among White patients with neovascular age-related macular degeneration (nAMD) using non-indocyanine green angiography (ICGA) criteria DESIGN: Multicenter, multinational, retrospective, cross-sectional study. METHODS: A total of 208 treatment-naive eyes from Hispanic and non-Hispanic White individuals diagnosed with nAMD were included. All underwent color fundus photography (CFP), optical coherence tomography (OCT), and fluorescein angiography (FFA). De-identified images of study eyes were sent to 2 groups of graders. Group 1 reviewed CFP, OCT, and FFA to confirm nAMD diagnosis. Group 2 reviewed CFP and OCT to determine highly suggestive features for PCV. Probable PCV diagnosis defined as the presence of ≥2 of 4 highly suggestive features for PCV: notched or fibrovascular pigment epithelial detachment (PED) on CFP, sharply-peaked PED, notched PED, and hyperreflective ring on OCT. RESULTS: Eleven eyes were excluded because of poor image quality (6) or non-nAMD diagnosis (5). Of 197 eligible eyes (197 patients), the mean age (SD) was 78.8 years (8.9), 44.2% were men, 26.4% were Hispanic, and 73.6% were non-Hispanic White individuals; 41.1%, 23.4%, 9.1%, and 2.5% had ≥1, ≥2, ≥3, and 4 highly suggestive features. Results showed that 23.4% (95% CI, 17.6%-29.9%) had probable PCV diagnosis. Predominantly occult CNV was more frequently found in probable PCV than nAMD subgroup (84.8% vs 64.9%, P = .01). Hispanic White individuals had a lower prevalence of probable PCV than non-Hispanic White individuals (9.6% vs 28.2%, P = .006) CONCLUSIONS: These findings suggest that probable PCV occurs between 17.6% and 29.9% in White individuals with nAMD, and more commonly in non-Hispanic than in Hispanic White individuals.


Subject(s)
Choroidal Neovascularization , Macular Degeneration , Polyps , Retinal Detachment , Male , Humans , Aged , Female , Choroidal Neovascularization/diagnosis , Choroidal Neovascularization/epidemiology , Retrospective Studies , Cross-Sectional Studies , White People , Fluorescein Angiography/methods , Tomography, Optical Coherence/methods , Polyps/diagnosis , Polyps/epidemiology , Choroid/blood supply
5.
J Peripher Nerv Syst ; 27(3): 215-224, 2022 09.
Article in English | MEDLINE | ID: mdl-35837722

ABSTRACT

Pathogenic variants in the genes encoding serine palmitoyl transferase (SPTLC1 or SPTLC2) are the most common causes of the rare peripheral nerve disorder Hereditary Sensory Neuropathy Type 1 (HSN1). Macular telangiectasia type 2 (MacTel), a retinal disorder associated with disordered serine-glycine metabolism, has been described in some patients with HSN1. This study aims to further investigate this association in a cohort of people with HSN1. Fourteen patients with a clinically and genetically confirmed diagnosis of HSN1 from the National Hospital for Neurology and Neurosurgery (NHNN, University College London Hospitals NHS Foundation Trust, London, United Kingdom) were recruited to the MacTel Registry, between July 2018 and April 2019. Two additional patients were identified from the dataset of the international clinical registry study (www.lmri.net). Ocular examination included fundus autofluorescence, blue light and infrared reflectance, macular pigment optical density mapping and optical coherence tomography. Twelve patients had a pathogenic variant in the SPTLC1 gene, with p.Cys133Trp in 11 cases (92%) and p.Cys133Tyr in one case (8%). Four patients had a variant in the SPTLC2 gene. None of the patients showed clinical evidence of MacTel. The link between HSN1 and MacTel seems more complex than can solely be explained by the genetic variants. An extension of the spectrum of SPTLC1/2-related disease with phenotypic pleiotropy is proposed. HSN1 patients should be screened for visual symptoms and referred for specialist retinal screening, but the association of the two diseases is likely to be variable and remains unexplained.


Subject(s)
Hereditary Sensory and Autonomic Neuropathies , Retinal Telangiectasis , Humans , Retinal Telangiectasis/complications , Retinal Telangiectasis/diagnosis , Retinal Telangiectasis/genetics , Serine , Serine C-Palmitoyltransferase/genetics
6.
Am J Ophthalmol Case Rep ; 25: 101311, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35146193

ABSTRACT

PURPOSE: To report a case of bullous central serous chorioretinopathy presenting with large choroidal effusions. OBSERVATIONS: A patient presented with typical features of bullous central serous chorioretinopathy with large choroidal effusions. He had a previous history of bullous central serous chorioretinopathy in his other eye. The condition worsened after a short course of oral prednisolone, consistent with central serous chorioretinopathy. Surgical management with sclerectomies resulted in resolution of serous retinal detachment, choroidal effusions and subfoveal fluid. CONCLUSIONS: We report choroidal effusions as a potential manifestation of central serous chorioretinopathy which may aid in our understanding in the pathogenic mechanisms of this condition. Furthermore, we demonstrate that surgical sclerectomies as a potential treatment option for serous retinal detachment and choroidal effusions in this condition.

7.
Am J Ophthalmol Case Rep ; 25: 101267, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35106403

ABSTRACT

PURPOSE: To visualize the mode of action of anti-vascular endothelial growth factor (anti-VEGFs) therapy on retinal neovascularization (RNV) in a patient with macular telangiectasia (MacTel) type 2 using a detailed three-dimensional data environment. OBSERVATION: A 60-year-old man presented with visual acuity loss and was diagnosed with MacTel type 2. Fluorescein angiography was not possible for safety reasons because of a history of severe reaction to fluorescein dye at his referring hospital. Optical coherence tomography angiography (OCTA) imaging revealed new retinal neovascular membranes (RNV) in the macula of both eyes. A marked reduction in the size of the RNV in both eyes was evident on volume-rendered three-dimensional OCTA retinal imaging after the first anti-VEGF injection. CONCLUSION AND IMPORTANCE: The ability to directly observe the effect of anti-VEGF injections on a RNV using three-dimensional OCTA was successfully demonstrated. This can be useful in patients with previous allergic and potentially lethal complications to fluorescein. In addition, enhanced three-dimensional spatial display of RNV leads to a greater understanding of the perfusion profile and the anatomical changes that occur in ocular neovascularization relative to surrounding tissue. This has the potential to provide insight into the pathobiology of angiogenesis.

9.
JAMA Ophthalmol ; 139(7): 769-776, 2021 07 01.
Article in English | MEDLINE | ID: mdl-34081099

ABSTRACT

Importance: Poor adherence or persistence to treatment can be a barrier to optimizing clinical practice (real-world) outcomes to intravitreal injection therapy in patients with neovascular age-related macular degeneration (nAMD). Currently, there is a lack of consensus on the definition and classification of adherence specific to this context. Objective: To describe the development and validation of terminology on patient nonadherence and nonpersistence to anti-vascular endothelial growth factor therapy. Design, Setting, and Participants: Following a systematic review of currently used terminology in the literature, a subcommittee panel of retinal experts developed a set of definitions and classification for validation. Definitions were restricted to use in patients with nAMD requiring intravitreal anti-vascular endothelial growth factor therapy. Validation by the full nAMD Barometer Leadership Coalition was established using a modified Delphi approach, with predetermined mean scores of 7.5 or more signifying consensus. Subsequent endorsement of the definitions was provided from a second set of retinal experts, with more than 50% members agreeing or strongly agreeing with all definitions. Main Outcomes and Measures: Development of consensus definitions for the terms adherence and persistence and a classification system for the factors associated with treatment nonadherence or nonpersistence in patients with nAMD. Results: Nonadherence was defined as missing 2 or more treatment or monitoring visits over a period of 12 months, with a visit considered missed if it exceeded more than 2 weeks from the recommended date. Nonpersistence was defined by nonattendance or an appointment not scheduled within the last 6 months. The additional terms planned discontinuation and transfer of care were also established. Reasons for treatment nonadherence and nonpersistence were classified into 6 dimensions: (1) patient associated, (2) condition associated, (3) therapy associated, (4) health system and health care team associated, (5) social/economic, and (6) other, with subcategories specific to treatment for nAMD. Conclusions and Relevance: This classification system provides a framework for assessing treatment nonadherence and nonpersistence over time and across different health settings in the treatment of nAMD with current intravitreal anti-vascular endothelial growth factor treatments. This may have additional importance, given the potential association of the coronavirus pandemic on adherence to treatment in patients with nAMD.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Macular Degeneration/drug therapy , Medication Adherence , Neovascularization, Pathologic , Practice Patterns, Physicians' , Terminology as Topic , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Angiogenesis Inhibitors/adverse effects , Consensus , Delphi Technique , Humans , Intravitreal Injections , Macular Degeneration/metabolism , Macular Degeneration/pathology , Signal Transduction , Socioeconomic Factors , Vascular Endothelial Growth Factor A/metabolism
10.
Clin Exp Optom ; 104(6): 672-683, 2021 08.
Article in English | MEDLINE | ID: mdl-33899681

ABSTRACT

This review explores how optical coherence tomography has guided our assessment of vitreomacular disorders. Vitreomacular disorders (VMD), such as macular holes and epiretinal membranes are common and potentially sight threatening. The introduction and widespread use of optical coherence tomography (OCT) imaging technology has transformed our ability to visualise the vitreoretinal interface. This review discusses the pathogenesis and updated classification scheme for VMD in the OCT era. Imaging biomarkers and the treatment algorithm, including the role of novel therapeutics, for managing patients with VMD are presented.


Subject(s)
Epiretinal Membrane , Retinal Perforations , Humans , Tomography, Optical Coherence , Vitreous Body
11.
Sci Rep ; 11(1): 4738, 2021 02 26.
Article in English | MEDLINE | ID: mdl-33637772

ABSTRACT

To analyze functional and anatomical response patterns to dexamethasone (DEX) implant in diabetic macular edema (DME), to describe proportion of responders and non-responders, and to propose a new DME grading system. Retrospective, multicenter, observational cohort study. Naïve and non-naïve DME patients were treated with DEX, with visual acuity (VA) ≥ 0.2 logMAR and central subfield thickness (CST) of ≥ 300 µm. Functional and anatomical responses were graded after 2 and 4 months, and categorized as early and stable improvement, early and progressive improvement, pendular response, delayed improvement, and persistent non-response. 417 eyes were included (175 treatment naïve eyes). Compared to non-naïve eyes, naïve eyes showed a very good functional response (VA gain ≥ 10 letters) more frequently after 2 and 4 months (56% and 57% [naïve] vs. 33% and 28% [non-naïve], p < 0.001). A VA gain < 5 letters (non-response) after 2 and 4 months was seen in 18% and 16% of naïve eyes, and in 49% and 53% of non-naïve eyes (p < 0.001). A lack of anatomical response was rare in both groups, but more frequently in non-naïve eyes (12% vs. 4%, p = 0.003). Functionally and anatomically, naïve eyes showed most frequently an early and stable improvement (functionally: 77/175 44%; anatomically: 123/175 eyes, 70%). Most non-naïve eyes experienced no significant improvement functionally (97/242 eyes, 40%), despite a mostly early and stable improvement anatomical response pattern (102/242 eyes, 42%). Functional but not anatomical response patterns were influenced by baseline VA. Naïve and non-naïve eyes show different functional and anatomical response patterns to DEX implant. Functional non-responders are rare in naïve eyes, whereas anatomical non-response is unusual in both groups.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Dexamethasone/therapeutic use , Diabetic Retinopathy/drug therapy , Macular Edema/drug therapy , Aged , Cohort Studies , Diabetic Retinopathy/pathology , Female , Humans , Intravitreal Injections , Macular Edema/pathology , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Visual Acuity/drug effects
12.
Ophthalmology ; 128(2): 234-247, 2021 02.
Article in English | MEDLINE | ID: mdl-32763265

ABSTRACT

TOPIC: Systematic review of risk factors for nonadherence and nonpersistence to intravitreal anti-vascular endothelial growth factor (VEGF) injection therapy for neovascular age-related macular degeneration (nAMD). CLINICAL RELEVANCE: Lack of adherence (nonadherence) or undertreatment (nonpersistence) with respect to evidence from clinical trials remains a significant barrier to optimizing real-world outcomes for patients with nAMD. Contributing factors and strategies to address this are poorly understood. METHODS: Studies that reported factors for nonadherence and nonpersistence to anti-VEGF therapy as well as studies examining strategies to improve this were included. Trial eligibility and data extraction were conducted according to Cochrane review methods. Risk of bias was assessed using the Mixed Method Assessment Tool and certainty of evidence evaluated according to the GRADE Confidence in the Evidence from Reviews of Qualitative Research tool. Data were collated descriptively. RESULTS: Of the 1284 abstract results screened, 124 articles were assessed in full and 37 studies met the inclusion criteria. Definitions of nonadherence and nonpersistence varied or were not reported. Nonpersistence occurred early, with up to 50% of patients stopping treatment by 24 months. High rates of nonadherence were similarly reported, occurring in 32% to 95% of patients. Certainty of this finding was downgraded to a moderate level because of the heterogeneity in definitions used across studies. Multiple factors determine nonadherence and nonpersistence, including at the condition, therapy, patient, social/economic, and health systems/healthcare team levels. Moderate quality evidence points to lower baseline vision and poorer response to treatment as condition-related variables. The effects of other factors were of lower certainty, predominantly due to small numbers and potential biases in retrospective assessment. Although many factors are not modifiable (e.g., patient comorbidity), other factors are potentially correctable (e.g., lack of transport or mismatched patient expectations). Evidence on strategies to improve adherence and persistence is limited, but where available, these have proven effective. CONCLUSIONS: Awareness of factors related to poor patient adherence and persistence in nAMD could help identify at-risk populations and improve real-world outcomes. Further work is required to develop uniform definitions and establish high-quality evidence on interventions that can be easily implemented.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Choroidal Neovascularization/drug therapy , Patient Compliance/statistics & numerical data , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Wet Macular Degeneration/drug therapy , Choroidal Neovascularization/physiopathology , Humans , Intravitreal Injections , Retrospective Studies , Visual Acuity/physiology , Wet Macular Degeneration/physiopathology
16.
Transl Vis Sci Technol ; 9(4): 27, 2020 03.
Article in English | MEDLINE | ID: mdl-32818114

ABSTRACT

Purpose: To determine the extent of remnant cone structure within early foveal ellipsoid zone (EZ) lesions in macular telangiectasia type 2 longitudinally using both confocal and split detector adaptive optics scanning light ophthalmoscopy (AOSLO). Methods: Spectral domain optical coherence tomography (SDOCT), confocal and split detector AOSLO were acquired from seven patients (10 eyes) with small (early) EZ lesions on SDOCT secondary to macular telangiectasia type 2 at baseline, 6 months, and 12 months. The presence of cone structure on AOSLO in areas of EZ loss as well as cones at 1° eccentricity, and their change over time were quantified. Results: By split detector AOSLO, remnant cone structure was identified within and on the borders of all foveal EZ lesions. Within the extent of these lesions, cone spacing ranged from 4.97 to 9.95 µm at baseline, 5.30 to 6.10 µm at 6 months, and 4.99 to 7.12 µm at 12 months. Four eyes with significantly smaller EZ lesions showed evidence of recovery of EZ reflectivity on SDOCT B-scans. Remnant cone structure was identified in some areas where EZ reflectivity recovered at the following time point. Eyes that showed recovery of EZ reflectivity had a continuous external limiting membrane. Conclusions: Remnant cone structure can persist within small SDOCT-defined EZ lesions, which can wax and wane in appearance over time. AOSLO can help to inform the interpretation of SDOCT imaging. Translational Relevance: The absence of EZ in early macular telangiectasia type 2 and other retinal conditions needs careful interpretation because it does not always indicate an absence of underlying cone structure. The integrity of the external limiting membrane may better predict the presence of remnant cone structure and recovery of EZ reflectivity.


Subject(s)
Fovea Centralis , Humans , Ophthalmoscopy , Retinal Cone Photoreceptor Cells , Visual Acuity
17.
Acta Ophthalmol ; 98(7): e801-e806, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32115886

ABSTRACT

PURPOSE: To investigate clinical baseline characteristics and optical coherence tomography biomarkers predicting visual loss during observation in eyes with diabetic macular oedema (DMO) and good baseline visual acuity (VA). METHODS: A sub-analysis of a 12-month, retrospective study, including patients with baseline VA ≤0.1 logMAR (≥20/25 Snellen) and centre-involving DMO. The primary outcome measure was the correlation between baseline characteristics and VA loss ≥10 letters during follow-up. RESULTS: A total of 249 eyes were included in the initial study, of which 147 eyes were observed and 80 eyes received anti-vascular endothelial growth factor (VEGF) treatment at baseline. Visual acuity (VA) loss ≥10 letters occurred in 21.8% (observed cohort) and in 24.3% (treated cohort), respectively. Within observed eyes, presence of hyperreflective foci [HRF; odds ratio (OR): 3.18, p = 0.046], and disorganization of inner retina layers (DRIL; OR: 2.71, p = 0.026) were associated with a higher risk of VA loss ≥10 letters. In observed eyes with a combined presence of HRF, DRIL and ellipsoid zone (EZ) disruption, the risk of VA loss was further increased (OR: 3.86, p = 0.034). In eyes with combined presence of DRIL, HRF and EZ disruption, risk of VA loss was 46.7% (7/15 eyes) in the observed cohort, and 26.3% (5/19 eyes) in the treated cohort (p = 0.26). CONCLUSION: Patients with DMO and good baseline VA, managed by observation, are of increased risk for VA loss if DRIL, HRF and EZ disruption are present at baseline. Earlier treatment with anti-VEGF in these patients may potentially decrease the risk of VA loss at 12 months.


Subject(s)
Bevacizumab/administration & dosage , Diabetic Retinopathy/physiopathology , Macular Edema/physiopathology , Ranibizumab/administration & dosage , Visual Acuity , Angiogenesis Inhibitors/administration & dosage , Diabetic Retinopathy/diagnosis , Diabetic Retinopathy/drug therapy , Female , Fluorescein Angiography/methods , Follow-Up Studies , Fundus Oculi , Humans , Macular Edema/diagnosis , Macular Edema/drug therapy , Male , Middle Aged , Retrospective Studies , Tomography, Optical Coherence/methods , Treatment Outcome , Vascular Endothelial Growth Factor A/antagonists & inhibitors
18.
N Engl J Med ; 381(15): 1422-1433, 2019 10 10.
Article in English | MEDLINE | ID: mdl-31509666

ABSTRACT

BACKGROUND: Identifying mechanisms of diseases with complex inheritance patterns, such as macular telangiectasia type 2, is challenging. A link between macular telangiectasia type 2 and altered serine metabolism has been established previously. METHODS: Through exome sequence analysis of a patient with macular telangiectasia type 2 and his family members, we identified a variant in SPTLC1 encoding a subunit of serine palmitoyltransferase (SPT). Because mutations affecting SPT are known to cause hereditary sensory and autonomic neuropathy type 1 (HSAN1), we examined 10 additional persons with HSAN1 for ophthalmologic disease. We assayed serum amino acid and sphingoid base levels, including levels of deoxysphingolipids, in patients who had macular telangiectasia type 2 but did not have HSAN1 or pathogenic variants affecting SPT. We characterized mice with low serine levels and tested the effects of deoxysphingolipids on human retinal organoids. RESULTS: Two variants known to cause HSAN1 were identified as causal for macular telangiectasia type 2: of 11 patients with HSAN1, 9 also had macular telangiectasia type 2. Circulating deoxysphingolipid levels were 84.2% higher among 125 patients with macular telangiectasia type 2 who did not have pathogenic variants affecting SPT than among 94 unaffected controls. Deoxysphingolipid levels were negatively correlated with serine levels, which were 20.6% lower than among controls. Reduction of serine levels in mice led to increases in levels of retinal deoxysphingolipids and compromised visual function. Deoxysphingolipids caused photoreceptor-cell death in retinal organoids, but not in the presence of regulators of lipid metabolism. CONCLUSIONS: Elevated levels of atypical deoxysphingolipids, caused by variant SPTLC1 or SPTLC2 or by low serine levels, were risk factors for macular telangiectasia type 2, as well as for peripheral neuropathy. (Funded by the Lowy Medical Research Institute and others.).


Subject(s)
Hereditary Sensory and Autonomic Neuropathies/genetics , Mutation , Retinal Telangiectasis/genetics , Serine C-Palmitoyltransferase/genetics , Serine/metabolism , Sphingolipids/metabolism , Adult , Aged , Animals , DNA Mutational Analysis , Disease Models, Animal , Exome/genetics , Female , Hereditary Sensory and Autonomic Neuropathies/complications , Hereditary Sensory and Autonomic Neuropathies/metabolism , Humans , Lipid Metabolism , Macula Lutea/pathology , Male , Mice , Middle Aged , Pedigree , Retinal Telangiectasis/complications , Retinal Telangiectasis/metabolism , Risk Factors , Serine/blood , Sphingosine/analogs & derivatives , Sphingosine/analysis , Young Adult
19.
PLoS One ; 14(8): e0220063, 2019.
Article in English | MEDLINE | ID: mdl-31419240

ABSTRACT

PURPOSE: To benchmark the human and machine performance of spectral-domain (SD) and swept-source (SS) optical coherence tomography (OCT) image segmentation, i.e., pixel-wise classification, for the compartments vitreous, retina, choroid, sclera. METHODS: A convolutional neural network (CNN) was trained on OCT B-scan images annotated by a senior ground truth expert retina specialist to segment the posterior eye compartments. Independent benchmark data sets (30 SDOCT and 30 SSOCT) were manually segmented by three classes of graders with varying levels of ophthalmic proficiencies. Nine graders contributed to benchmark an additional 60 images in three consecutive runs. Inter-human and intra-human class agreement was measured and compared to the CNN results. RESULTS: The CNN training data consisted of a total of 6210 manually segmented images derived from 2070 B-scans (1046 SDOCT and 1024 SSOCT; 630 C-Scans). The CNN segmentation revealed a high agreement with all grader groups. For all compartments and groups, the mean Intersection over Union (IOU) score of CNN compartmentalization versus group graders' compartmentalization was higher than the mean score for intra-grader group comparison. CONCLUSION: The proposed deep learning segmentation algorithm (CNN) for automated eye compartment segmentation in OCT B-scans (SDOCT and SSOCT) is on par with manual segmentations by human graders.


Subject(s)
Tomography, Optical Coherence/statistics & numerical data , Algorithms , Artificial Intelligence/statistics & numerical data , Benchmarking/statistics & numerical data , Choroid/diagnostic imaging , Deep Learning/statistics & numerical data , Humans , Image Interpretation, Computer-Assisted/statistics & numerical data , Neural Networks, Computer , Observer Variation , Retina/diagnostic imaging , Sclera/diagnostic imaging , Vitreous Body/diagnostic imaging
20.
Transl Vis Sci Technol ; 8(3): 54, 2019 May.
Article in English | MEDLINE | ID: mdl-31293809

ABSTRACT

PURPOSE: We provide a proof of concept for the detailed characterization of retinal capillary features and surrounding photoreceptor mosaic using a customized nonadaptive optics angiography imaging system. METHODS: High-resolution fluorescein angiography (FFA) and/or indocyanine green angiography (ICGA) images were obtained using a modified Heidelberg retina angiograph (HRA2) device with a reduced scan angle enabling 3° field of view. Colocalized images of the photoreceptor mosaic also were captured in vivo using the same instrument. Visibility of vascular subbranches were compared between high-resolution images and conventional fundus angiography (FA) with a 30° field of view. RESULTS: High-resolution angiographic and infrared images (3° × 3° field of view, a 10-fold magnification) were obtained in 10 participants. These included seven patients with various retinal diseases, including myopic degeneration, diabetic retinopathy, macular telangiectasia, and central serous chorioretinopathy, as well as three healthy controls. Images of the retinal vasculature down to the capillary level were obtained on angiography with the ability to visualize a mean 1.2 levels more subbranches compared to conventional FA. In addition, imaging of the photoreceptor cone mosaic, to a sufficient resolution to calculate cone density, was possible. Movement of blood cells within the vasculature also was discernible on infrared videography. CONCLUSIONS: This exploratory study demonstrates that fast high-resolution angiography and cone visualization is feasible using a commercially available imaging system. TRANSLATIONAL RELEVANCE: This offers potential to better understand the relationship between the retinal neurovascular system in health and disease and the timing of therapeutic interventions in disease states.

SELECTION OF CITATIONS
SEARCH DETAIL