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1.
J Glaucoma ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38747721

RESUMO

PRCIS: In this meta-analysis of 6 studies and 5,269 patients, deep learning algorithms applied to AS-OCT demonstrated excellent diagnostic performance for closed-angle compared to gonioscopy, with a pooled sensitivity and specificity of 94% and 93.6%, respectively. PURPOSE: This study aimed to review the literature and compare the accuracy of deep learning algorithms (DLA) applied to anterior segment optical coherence tomography images (AS-OCT) against gonioscopy in detecting angle-closure in patients with glaucoma. METHODS: We performed a systematic review and meta-analysis evaluating DLA in AS-OCT images for the diagnosis of angle closure compared with gonioscopic evaluation. PubMed, Scopus, Embase, Lilacs, Scielo, and Cochrane Central Register of Controlled Trials were searched. The bivariate model was used to calculate pooled sensitivity and specificity. RESULTS: The initial search identified 214 studies, of which 6 were included for final analysis. The total study population included 5,269 patients. The combined sensitivity of the DLA compared with gonioscopy was 94.0% (95% CI 83.8%-97.9%), whereas the pooled specificity was 93.6% (95% CI 85.7%-97.3%). Sensitivity analyses removing each individual study showed a pooled sensitivity in the range of 90.1% to 95.1%. Similarly, specificity results ranged from 90.3 to 94.5% with the removal of each individual study and recalculation of pooled specificity. CONCLUSION: DLA applied to AS-OCT has excellent sensitivity and specificity in the identification of angle closure. This technology may be a valuable resource in the screening of populations without access to experienced ophthalmologists who perform gonioscopy.

2.
Transl Vis Sci Technol ; 13(5): 20, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38780955

RESUMO

Purpose: We sough to develop an automatic method of quantifying optic disc pallor in fundus photographs and determine associations with peripapillary retinal nerve fiber layer (pRNFL) thickness. Methods: We used deep learning to segment the optic disc, fovea, and vessels in fundus photographs, and measured pallor. We assessed the relationship between pallor and pRNFL thickness derived from optical coherence tomography scans in 118 participants. Separately, we used images diagnosed by clinical inspection as pale (n = 45) and assessed how measurements compared with healthy controls (n = 46). We also developed automatic rejection thresholds and tested the software for robustness to camera type, image format, and resolution. Results: We developed software that automatically quantified disc pallor across several zones in fundus photographs. Pallor was associated with pRNFL thickness globally (ß = -9.81; standard error [SE] = 3.16; P < 0.05), in the temporal inferior zone (ß = -29.78; SE = 8.32; P < 0.01), with the nasal/temporal ratio (ß = 0.88; SE = 0.34; P < 0.05), and in the whole disc (ß = -8.22; SE = 2.92; P < 0.05). Furthermore, pallor was significantly higher in the patient group. Last, we demonstrate the analysis to be robust to camera type, image format, and resolution. Conclusions: We developed software that automatically locates and quantifies disc pallor in fundus photographs and found associations between pallor measurements and pRNFL thickness. Translational Relevance: We think our method will be useful for the identification, monitoring, and progression of diseases characterized by disc pallor and optic atrophy, including glaucoma, compression, and potentially in neurodegenerative disorders.


Assuntos
Aprendizado Profundo , Fibras Nervosas , Disco Óptico , Fotografação , Software , Tomografia de Coerência Óptica , Humanos , Disco Óptico/diagnóstico por imagem , Disco Óptico/patologia , Tomografia de Coerência Óptica/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Fotografação/métodos , Adulto , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/citologia , Idoso , Doenças do Nervo Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/diagnóstico , Doenças do Nervo Óptico/patologia , Fundo de Olho
3.
Ophthalmic Physiol Opt ; 44(5): 963-976, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38563652

RESUMO

PURPOSE: To synthesise evidence across studies on factors associated with pathologic myopia (PM) onset and progression based on the META-analysis for Pathologic Myopia (META-PM) classification framework. METHODS: Findings from six longitudinal studies (5-18 years) were narratively synthesised and meta-analysed, using odds ratio (OR) as the common measure of association. All studies adjusted for baseline myopia, age and sex at a minimum. The quality of evidence was rated using the Grades of Recommendation, Assessment, Development and Evaluation framework. RESULTS: Five out of six studies were conducted in Asia. There was inconclusive evidence of an independent effect (or lack thereof) of ethnicity and sex on PM onset/progression. The odds of PM onset increased with greater axial length (pooled OR: 2.03; 95% CI: 1.71-2.40; p < 0.001), older age (pooled OR: 1.07; 1.05-1.09; p < 0.001) and more negative spherical equivalent refraction, SER (OR: 0.77; 0.68-0.87; p < 0.001), all of which were supported by an acceptable level of evidence. Fundus tessellation was found to independently increase the odds of PM onset in a population-based study (OR: 3.02; 2.58-3.53; p < 0.001), although this was only supported by weak evidence. There was acceptable evidence that greater axial length (pooled OR: 1.23; 1.09-1.39; p < 0.001), more negative SER (pooled OR: 0.87; 0.83-0.92; p < 0.001) and higher education level (pooled OR: 3.17; 1.36-7.35; p < 0.01) increased the odds of PM progression. Other baseline factors found to be associated with PM progression but currently supported by weak evidence included age (pooled OR: 1.01), severity of myopic maculopathy (OR: 3.61), intraocular pressure (OR: 1.62) and hypertension (OR: 0.21). CONCLUSIONS: Most PM risk/prognostic factors are not supported by an adequate evidence base at present (an indication that PM remains understudied). Current factors for which an acceptable level of evidence exists (limited in number) are unmodifiable in adults and lack personalised information. More longitudinal studies focusing on uncovering modifiable factors and imaging biomarkers are warranted.


Assuntos
Progressão da Doença , Miopia Degenerativa , Humanos , Miopia Degenerativa/fisiopatologia , Miopia Degenerativa/epidemiologia , Miopia Degenerativa/diagnóstico , Fatores de Risco , Refração Ocular/fisiologia
4.
BMC Med Res Methodol ; 24(1): 13, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233744

RESUMO

BACKGROUND: Community optometrists in Scotland have performed regular free-at-point-of-care eye examinations for all, for over 15 years. Eye examinations include retinal imaging but image storage is fragmented and they are not used for research. The Scottish Collaborative Optometry-Ophthalmology Network e-research project aimed to collect these images and create a repository linked to routinely collected healthcare data, supporting the development of pre-symptomatic diagnostic tools. METHODS: As the image record was usually separate from the patient record and contained minimal patient information, we developed an efficient matching algorithm using a combination of deterministic and probabilistic steps which minimised the risk of false positives, to facilitate national health record linkage. We visited two practices and assessed the data contained in their image device and Practice Management Systems. Practice activities were explored to understand the context of data collection processes. Iteratively, we tested a series of matching rules which captured a high proportion of true positive records compared to manual matches. The approach was validated by testing manual matching against automated steps in three further practices. RESULTS: A sequence of deterministic rules successfully matched 95% of records in the three test practices compared to manual matching. Adding two probabilistic rules to the algorithm successfully matched 99% of records. CONCLUSIONS: The potential value of community-acquired retinal images can be harnessed only if they are linked to centrally-held healthcare care data. Despite the lack of interoperability between systems within optometry practices and inconsistent use of unique identifiers, data linkage is possible using robust, almost entirely automated processes.


Assuntos
Registro Médico Coordenado , Prontuários Médicos , Humanos , Sistemas Computadorizados de Registros Médicos , Coleta de Dados , Escócia
5.
Eye (Lond) ; 38(6): 1208-1214, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38081936

RESUMO

OBJECTIVES: To investigate the association between intraocular pressure (IOP) and axial elongation rate in highly myopic children from the ZOC-BHVI High Myopia Cohort Study. METHODS: 162 eyes of 81 healthy children (baseline spherical equivalent: -6.25 D to -15.50 D) aged 7-12 years with non-pathological high myopia were studied over five biennial visits. The mean (SD) follow-up duration was 5.2 (3.3) years. A linear mixed-effects model (LMM) was used to assess the association between IOP (at time point t-1) and axial elongation rate (annual rate of change in AL from t-1 to t), controlling for a pre-defined set of covariates including sex, age, central corneal thickness, anterior chamber depth and lens thickness (at t-1). LMM was also used to assess the contemporaneous association between IOP and axial length (AL) at t, controlling for the same set of covariates (at t) as before. RESULTS: Higher IOP was associated with slower axial growth (ß = -0.01, 95% CI -0.02 to -0.005, p = 0.001). There was a positive contemporaneous association between IOP and AL (ß = 0.03, 95% CI 0.01-0.05, p = 0.004), but this association became progressively less positive with increasing age, as indicated by a negative interaction effect between IOP and age on AL (ß = -0.01, 95% CI -0.01 to -0.003, p = 0.001). CONCLUSIONS: Higher IOP is associated with slower rather than faster axial growth in children with non-pathological high myopia, an association plausibly confounded by the increased influence of ocular compliance on IOP.


Assuntos
Glaucoma , Miopia , Criança , Humanos , Pressão Intraocular , Estudos de Coortes , Olho/patologia , Glaucoma/patologia , Refração Ocular , Comprimento Axial do Olho/patologia
6.
Br J Ophthalmol ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37923373

RESUMO

BACKGROUND/AIMS: The goal of health research is to improve patients care and outcomes. Thus, it is essential that research addresses questions that are important to patients and clinicians. The aim of this study was to develop a list of priorities for glaucoma research involving stakeholders from different countries in Europe. METHODS: We used a three-phase method, including a two-round electronic Delphi survey and a workshop. The clinician and patient electronic surveys were conducted in parallel and independently. For phase I, the survey was distributed to patients from 27 European countries in 6 different languages, and to European Glaucoma Society members, ophthalmologists with expertise in glaucoma care, asking to name up to five research priorities. During phase II, participants were asked to rank the questions identified in phase I using a Likert scale. Phase III was a 1 day workshop with patients and clinicians. The purpose was to make decisions about the 10 most important research priorities using the top 20 priorities identified by patients and clinicians. RESULTS: In phase I, 308 patients and 150 clinicians were involved. In phase II, the highest-ranking priority for both patients and clinicians was 'treatments to restore vision'. In phase III, eight patients and four clinicians were involved. The top three priorities were 'treatments to stop sight loss', 'treatments to restore vision' and 'improved detection of worsening glaucoma'. CONCLUSION: We have developed a list of priorities for glaucoma research involving clinicians and patients from different European countries that will help guide research efforts and investment.

7.
BMJ Open Ophthalmol ; 8(1)2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057105

RESUMO

BACKGROUND: This study aims to characterise the symptoms and clinical features of optic neuritis (ON) following SARS-CoV-2 infection and vaccination. METHOD: A literature search was conducted in four databases (PubMed, Medline, Embase and Google Scholar) to identify relevant case reports and case series. The records were screened and articles adhering to the inclusion criteria were critically appraised. RESULTS: Sixty-eight studies were found to be eligible for inclusion, including 34 reporting ON following SARS-CoV-2 infection and an equal number reporting cases postvaccination. In total 93 patients and 125 eyes were included. The infection cohort included 42 patients and 56 eyes, 51.2% were female and 33.3% experienced bilateral ON. The mean visual acuity was 1.64 log of minimum angle of resolution (LogMAR), while pain was present in 77.8%. Oligoclonal bands were present in 3 patients, myelin oligodendrocyte glycoprotein (MOG) antibodies in 18 patients and AQP-4 antibodies in 4 patients. The vaccination cohort included 51 patients and 69 eyes. 60.8% were female and 35.3% had a bilateral ON. The mean visual acuity was 0.93 LogMAR. Oligoclonal bands were present in 46.7%, MOG antibodies in nine patients and AQP-4 antibodies in three patients. CONCLUSION: Patients with ON post-SARS-CoV infection were more likely to experience severe visual impairment than in cases following vaccination. Further research is required to outline the clinical features of ON after COVID-19 infection and vaccination, and establish causality.


Assuntos
COVID-19 , Neurite Óptica , Humanos , Feminino , Masculino , Bandas Oligoclonais , Autoanticorpos , Estudos Retrospectivos , Glicoproteína Mielina-Oligodendrócito , Neurite Óptica/epidemiologia , Vacinação , COVID-19/prevenção & controle
8.
Sci Rep ; 13(1): 19605, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37949880

RESUMO

Several observational studies have investigated the association between cannabis use and intraocular pressure, but its association with primary open-angle glaucoma (POAG) remains unclear. In this study, we leveraged human genetic data to assess through Mendelian randomization (MR) whether cannabis use affects POAG. We used five single-nucleotide polymorphisms (SNPs) associated with lifetime cannabis use (P-value < 5 × 10-8) from a genome-wide association study (GWAS) (N = 184,765) by the International Cannabis Consortium, 23andMe, and UK Biobank and eleven SNPs associated with cannabis use disorder (P-value < 5 × 10-7) from a GWAS meta-analysis of (17,068 cases and 357,219 controls of European descent) from Psychiatric Genomics Consortium Substance Use Disorders working group, Lundbeck Foundation Initiative for Integrative Psychiatric Research, and deCode. We associated the selected five SNPs from the GWAS of lifetime cannabis use and the eleven SNPs from the GWAS of cannabis use disorder, with the largest to date GWAS meta-analysis of POAG (16,677 cases and 199,580 controls). MR analysis suggested no evidence for a causal association of lifetime cannabis use and cannabis use disorder with POAG (odds ratio (OR) of outcome per doubling of the odds of exposure (95% confidence interval): 1.04 (0.88; 1.23) for lifetime cannabis use and 0.97 (0.92; 1.03) for cannabis use disorder). Sensitivity analyses to address pleiotropy and weak instrument bias yielded similar estimates to the primary analysis. In conclusion, our results do not support a causal association between cannabis use and POAG.


Assuntos
Cannabis , Glaucoma de Ângulo Aberto , Abuso de Maconha , Humanos , Estudo de Associação Genômica Ampla , Cannabis/efeitos adversos , Cannabis/genética , Análise da Randomização Mendeliana/métodos , Glaucoma de Ângulo Aberto/induzido quimicamente , Glaucoma de Ângulo Aberto/epidemiologia , Glaucoma de Ângulo Aberto/genética , Polimorfismo de Nucleotídeo Único
9.
Eye (Lond) ; 37(18): 3854-3860, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37563427

RESUMO

BACKGROUND/OBJECTIVES: Cataract surgery with intraocular lens (IOL) implantation is one of the most commonly performed surgeries worldwide. Within the UK, publicly funded cataract surgery is remunerated by two models: (1) "block contract" (BC), which commissions organisations to deliver whole service pathways without considering specific activity items; or (2) "payment by results" (PbR), which pays a tariff price for each procedure. This study aimed to examine the association between remuneration model and the cost and types of IOL used. SUBJECTS/METHODS: Cataract operations recorded on the Royal College of Ophthalmologists' National Ophthalmology Database were included, with additional data collected for remuneration model from NHS England and cost of IOL from the NHS Spend Comparison Service. RESULTS: We included 907,052 cataract operations from 87 centres. The majority of operations were performed in PbR centres (456 198, 50.3%), followed by BC centres (240 641, 26.5%) and mixed models centres (210 213, 23.2%). The mean price of hydrophobic (n = 7) and hydrophilic IOLs (n = 5) were £45.72 and £42.86, respectively. Hydrophobic IOLs were predominantly used (650 633, 71.7%) and were significantly more commonly used in centres remunerated by BC (96.5% vs. 3.5%) than those by PbR (65.7% vs. 34.3%) when compared to hydrophilic IOLs (p < 0.001). CONCLUSIONS: This study demonstrated that the IOL choice may be perversely incentivised by the IOL cost and remuneration model. Although hydrophobic IOLs are more expensive at the point of surgery, their potential longer-term cost-effectiveness due to reduced requirement for YAG capsulotomy should be considered.


Assuntos
Extração de Catarata , Catarata , Lentes Intraoculares , Oftalmologistas , Oftalmologia , Humanos , Implante de Lente Intraocular/métodos , Remuneração , Inglaterra , Complicações Pós-Operatórias
11.
J Glaucoma ; 32(3): 159-164, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36877821

RESUMO

PRCIS: Automated gonioscopy provided good-quality images of the anterior chamber angle. There was a short learning curve for operators, and the examination was well tolerated by patients. Patients expressed a preference for automated gonioscopy compared with traditional gonioscopy. PURPOSE: The purpose of this study was to assess the feasibility of using a desktop automated gonioscopy camera in glaucoma clinics by examining patient tolerability, ease of use, and image quality and comparing patient preference compared with traditional gonioscopy. PATIENTS AND METHODS: A prospective study was conducted in a university hospital clinic. Traditional gonioscopy was performed followed by imaging of the iridocorneal angle (ICA) using the Nidek GS-1 camera by 2 glaucoma specialists. Participants were asked to rate the comfort of automated gonioscopy and which method they preferred. The clinicians graded the ease of acquisition for each patient, and the image quality was reviewed by a grader. RESULTS: Forty-three eyes of 25 participants were included. Sixty-eight percent of participants viewed automated gonioscopy as "extremely comfortable," and the remainder reported it "comfortable". Forty percent preferred automated gonioscopy compared with traditional gonioscopy, while 52% were equivocal. Clinicians scored 32% of participants as "somewhat difficult" to the image. In 46% of eyes, good-quality photographs were obtained for 360 degrees of the ICA. Only 1 eye had no parts of the ICA clearly visible. Seventy-four percent of eyes had at least half of the ICA clearly visible in all 4 quadrants. CONCLUSION: Automated gonioscopy provided good-quality images of the ICA for most patients. It was often not possible to image the entire 360 degrees at the first attempt, but the examination was comfortable for patients, and only 8% preferred traditional gonioscopy to the automated photographic examination.


Assuntos
Glaucoma , Pressão Intraocular , Humanos , Estudos de Viabilidade , Gonioscopia , Estudos Prospectivos , Fotografação , Glaucoma/diagnóstico
12.
Eye (Lond) ; 37(16): 3376-3381, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36959313

RESUMO

BACKGROUND: Socioeconomic deprivation is associated with higher odds of chronic diseases, with many individuals living with more than one illness. This study aimed to examine the relationship between deprivation and severity of glaucoma at diagnosis, an important risk factor for glaucoma blindness. METHODS: A retrospective study of 472 consecutive patients referred by community optometrists to the glaucoma clinic at a university hospital was performed. Glaucoma severity was determined by standard automated perimetry mean deviation (MD) in the worse eye. The Scottish Index of Multiple Deprivation (SIMD) was determined for each patient as a measure of deprivation based on postcode. Regression analyses were performed to determine the relationship between visual field MD and SIMD. RESULTS: There was a significant relationship between higher levels of deprivation (lower SIMD) and worse severity of glaucoma at diagnosis. 32 of 472 patients (6.8%) had a MD of ≤-6 dB and 11 (2.3%) ≤-12 dB in their better eye. MD in the worse eye was 0.04 dB (95% CI 0.014 to 0.062 dB, P = 0.002) worse for each 100-point decrease in SIMD, with lower SIMD indicating a higher level of deprivation. A higher proportion of patients living in most deprived areas had a MD ≤ -6 dB or ≤ -12 dB at presentation compared to those living in the least deprived areas (14.3% versus 6.8% for ≤ -6 dB and 4.8% versus 0.8% for ≤ -12 dB). CONCLUSIONS: Higher levels of deprivation were associated with worse glaucoma severity at presentation. The reasons for poorer outcomes in those from more deprived communities need further study so that inequalities can be addressed and the frequency of patients presenting with advanced glaucoma reduced.


Assuntos
Glaucoma , Transtornos da Visão , Humanos , Estudos Retrospectivos , Transtornos da Visão/diagnóstico , Transtornos da Visão/etiologia , Glaucoma/diagnóstico , Glaucoma/complicações , Campos Visuais , Testes de Campo Visual , Índice de Gravidade de Doença
14.
Eye (Lond) ; 37(3): 501-505, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35177790

RESUMO

BACKGROUND/OBJECTIVES: Intraocular pressure (IOP) is the primary modifiable risk factor in the progression of glaucoma. The ICare HOME is a self-tonometer which empowers patients to measure their own IOP and allows a more complete picture of diurnal IOP. This project aims to determine the feasibility of teaching patients to perform self-tonometry remotely using a remote video link. SUBJECTS/METHODS: This prospective study involved 12 patients with glaucoma attending an outpatient ophthalmology clinic. Participants were provided with a rebound tonometer (Icare HOME) and instructions to attend remote teaching from home. An optometrist conducted a 30 min live video training session via NearMe with each patient. Following training, participants were asked to measure their own IOP, observed remotely by the optometrist. Successful participants were asked to take a series of home IOP measurements over 48 h. Questionnaires were used to evaluate perceptions on home tonometry and remote training. RESULTS: Participants had an average age of 60.1 ± 15.5 years. 58% (7 of 12) were female. 83% (10 of 12) obtained successful diurnal measurements at home. All participants were happy with remote teaching, and none would have preferred training to be conducted face-to-face. All participants were interested in continuing home IOP monitoring. CONCLUSIONS: Most patients were able to perform home tonometry successfully when taught remotely, with a success rate similar to previously reported rates for face-to-face teaching using the same device. Most participants were receptive to using video calling as a platform for teaching home tonometry.


Assuntos
Glaucoma , Hipertensão Ocular , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Tonometria Ocular , Pressão Intraocular
15.
Eye (Lond) ; 37(9): 1922-1927, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36209251

RESUMO

BACKGROUND/OBJECTIVES: Poor adherence to medical therapy is a major challenge to the effective treatment of chronic diseases including glaucoma. Potential factors influencing adherence include treatment complexity and patient understanding of disease and health beliefs. An increasing number of patients are seen in virtual clinics, where there is no face-to-face consultation, potentially reducing opportunities for patient education and reinforcement of the importance of treatment. The aim of this study was to examine adherence among patients attending a virtual glaucoma clinic. METHODS: 100 consecutive patients attending the virtual clinic were surveyed, with 78 using topical medications included in the analysis. All patients completed a validated adherence questionnaire with a score of >2 defined as poor adherence. The relationship between adherence and age, sex, duration since diagnosis, and disease severity was examined. RESULTS: The mean age was 73.1 ± 13.4 years, with an average mean deviation of -5.9 ± 5.5 dB and duration since first diagnosis of 9.0 ± 5.7 years. 93.6% reported self-instilling eye drops. Seventy-one patients (91.0 %) had good self-reported adherence. Multivariate logistic regression revealed those instilling eye drops independently had higher odds of good adherence. CONCLUSIONS: The level of medication adherence in the virtual glaucoma clinic was higher than adherence in previous studies examining patients attending face-to-face clinics. Virtual clinics should incorporate methods to ensure effective two-way communication with patients and strategies for patient education.


Assuntos
Anti-Hipertensivos , Glaucoma , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Glaucoma/tratamento farmacológico , Adesão à Medicação , Inquéritos e Questionários , Soluções Oftálmicas
16.
BMC Ophthalmol ; 22(1): 54, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35123441

RESUMO

BACKGROUND: Metrics derived from the human eye are increasingly used as biomarkers and endpoints in studies of cardiovascular, cerebrovascular and neurological disease. In this context, it is important to account for potential confounding that can arise from differences in ocular dimensions between individuals, for example, differences in globe size. METHODS: We measured axial length, a geometric parameter describing eye size from T2-weighted brain MRI scans using three different image analysis software packages (Mango, ITK and Carestream) and compared results to biometry measurements from a specialized ophthalmic instrument (IOLMaster 500) as the reference standard. RESULTS: Ninety-three healthy research participants of mean age 51.0 ± SD 5.4 years were analyzed. The level of agreement between the MRI-derived measurements and the reference standard was described by mean differences as follows, Mango - 0.8 mm; ITK - 0.5 mm; and Carestream - 0.1 mm (upper/lower 95% limits of agreement across the three tools ranged from 0.9 mm to - 2.6 mm). Inter-rater reproducibility was between - 0.03 mm and 0.45 mm (ICC 0.65 to 0.93). Intra-rater repeatability was between 0.0 mm and - 0.2 mm (ICC 0.90 to 0.95). CONCLUSIONS: We demonstrate that axial measurements of the eye derived from brain MRI are within 3.5% of the reference standard globe length of 24.1 mm. However, the limits of agreement could be considered clinically significant. Axial length of the eye obtained from MRI is not a replacement for the precision of biometry, but in the absence of biometry it could provide sufficient accuracy to act as a proxy. We recommend measuring eye axial length from MRI in studies that do not have biometry but use retinal imaging to study neurodegenerative changes so as to control for differing eye size across individuals.


Assuntos
Interferometria , Tomografia de Coerência Óptica , Comprimento Axial do Olho/anatomia & histologia , Comprimento Axial do Olho/diagnóstico por imagem , Biometria , Encéfalo/diagnóstico por imagem , Olho/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Pessoa de Meia-Idade , Neuroimagem , Reprodutibilidade dos Testes
18.
BMJ Open Ophthalmol ; 6(1): e000898, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34901467

RESUMO

OBJECTIVE: To develop and test a deep learning (DL) model for semantic segmentation of anatomical layers of the anterior chamber angle (ACA) in digital gonio-photographs. METHODS AND ANALYSIS: We used a pilot dataset of 274 ACA sector images, annotated by expert ophthalmologists to delineate five anatomical layers: iris root, ciliary body band, scleral spur, trabecular meshwork and cornea. Narrow depth-of-field and peripheral vignetting prevented clinicians from annotating part of each image with sufficient confidence, introducing a degree of subjectivity and features correlation in the ground truth. To overcome these limitations, we present a DL model, designed and trained to perform two tasks simultaneously: (1) maximise the segmentation accuracy within the annotated region of each frame and (2) identify a region of interest (ROI) based on local image informativeness. Moreover, our calibrated model provides results interpretability returning pixel-wise classification uncertainty through Monte Carlo dropout. RESULTS: The model was trained and validated in a 5-fold cross-validation experiment on ~90% of available data, achieving ~91% average segmentation accuracy within the annotated part of each ground truth image of the hold-out test set. An appropriate ROI was successfully identified in all test frames. The uncertainty estimation module located correctly inaccuracies and errors of segmentation outputs. CONCLUSION: The proposed model improves the only previously published work on gonio-photographs segmentation and may be a valid support for the automatic processing of these images to evaluate local tissue morphology. Uncertainty estimation is expected to facilitate acceptance of this system in clinical settings.

19.
Drugs ; 81(17): 2017-2033, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34724172

RESUMO

OBJECTIVE: To evaluate the intraocular pressure (IOP)-lowering efficacy and safety of 10 and 15 µg bimatoprost implant in patients with open-angle glaucoma (OAG) or ocular hypertension (OHT). METHODS: This randomized, 20-month, multicenter, masked, parallel-group, phase 3 trial enrolled 528 patients with OAG or OHT and an open iridocorneal angle inferiorly in the study eye. Study eyes were administered 10 or 15 µg bimatoprost implant on day 1, week 16, and week 32, or twice-daily topical timolol maleate 0.5%. Primary endpoints were IOP and IOP change from baseline through week 12. Safety measures included treatment-emergent adverse events (TEAEs) and corneal endothelial cell density (CECD). RESULTS: Both 10 and 15 µg bimatoprost implant met the primary endpoint of noninferiority to timolol in IOP lowering through 12 weeks. Mean IOP reductions from baseline ranged from 6.2-7.4, 6.5-7.8, and 6.1-6.7 mmHg through week 12 in the 10 µg implant, 15 µg implant, and timolol groups, respectively. IOP lowering was similar after the second and third implant administrations. Probabilities of requiring no IOP-lowering treatment for 1 year after the third administration were 77.5% (10 µg implant) and 79.0% (15 µg implant). The most common TEAE was conjunctival hyperemia, typically temporally associated with the administration procedure. Corneal TEAEs of interest (primarily corneal endothelial cell loss, corneal edema, and corneal touch) were more frequent with the 15 than the 10 µg implant and generally were reported after repeated administrations. Loss in mean CECD from baseline to month 20 was ~ 5% in 10 µg implant-treated eyes and ~ 1% in topical timolol-treated eyes. Visual field progression (change in the mean deviation from baseline) was reduced in the 10 µg implant group compared with the timolol group. CONCLUSIONS: The results corroborated the previous phase 3 study of the bimatoprost implant. The bimatoprost implant met the primary endpoint and effectively lowered IOP. The majority of patients required no additional treatment for 12 months after the third administration. The benefit-risk assessment favored the 10 over the 15 µg implant. Studies evaluating other administration regimens with reduced risk of corneal events are ongoing. The bimatoprost implant has the potential to improve adherence and reduce treatment burden in glaucoma. CLINICALTRIALS. GOV IDENTIFIER: NCT02250651.


Assuntos
Anti-Hipertensivos/uso terapêutico , Bimatoprost/uso terapêutico , Implantes de Medicamento/uso terapêutico , Glaucoma de Ângulo Aberto/tratamento farmacológico , Hipertensão Ocular/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Bimatoprost/administração & dosagem , Bimatoprost/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Implantes de Medicamento/administração & dosagem , Implantes de Medicamento/efeitos adversos , Feminino , Humanos , Pressão Intraocular/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Timolol/uso terapêutico , Adulto Jovem
20.
Sci Rep ; 11(1): 22814, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34819594

RESUMO

The use of 2D alpha-shapes (α-shapes) to quantify morphological features of the retinal microvasculature could lead to imaging biomarkers for proliferative diabetic retinopathy (PDR). We tested our approach using the MESSIDOR dataset that consists of colour fundus photographs from 547 healthy individuals, 149 with mild diabetic retinopathy (DR), 239 with moderate DR, 199 pre-PDR and 53 PDR. The skeleton (centrelines) of the automatically segmented retinal vasculature was represented as an α-shape and the proposed parameters, complexity ([Formula: see text]), spread (OpA), global shape (VS) and presence of abnormal angiogenesis (Gradα) were computed. In cross-sectional analysis, individuals with PDR had a lower [Formula: see text], OpA and Gradα indicating a vasculature that is more complex, less spread (i.e. dense) and the presence of numerous small vessels. The results show that α-shape parameters characterise vascular abnormalities predictive of PDR (AUC 0.73; 95% CI [0.73 0.74]) and have therefore potential to reveal changes in retinal microvascular morphology.


Assuntos
Retinopatia Diabética/patologia , Microvasos/patologia , Fotografação , Neovascularização Retiniana/patologia , Vasos Retinianos/patologia , Humanos , Interpretação de Imagem Assistida por Computador , Reconhecimento Automatizado de Padrão , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
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