RESUMO
BACKGROUND: To evaluate different mechanisms of primary angle closure and to quantify anterior chamber parameters in these mechanisms using anterior segment optical coherence tomography in an Asian population. DESIGN: Hospital-based cross-sectional observational study. PARTICIPANTS: Forty-eight consecutive patients with primary angle closure glaucoma. METHODS: Patients underwent complete ophthalmic examination and imaging of nasal-temporal angles with anterior segment optical coherence tomography. Images were categorized into four primary angle closure mechanisms: pupil block, plateau iris configuration, Thick peripheral iris roll and exaggerated lens vault. Parameters computed: anterior chamber depth central, anterior chamber depth at 1000 µm and 2000 µm anterior to scleral spur, lens vault, anterior chamber area, angle opening distance, trabecular iris space area and iris thickness. MAIN OUTCOME MEASURE: Anterior chamber parameters and primary angle closure mechanisms. RESULTS: Mean values of anterior chamber depths: central (P < 0.001), at 2000 µm (P < 0.001), 1000 µm (P < 0.001), lens vault (P < 0.001), anterior chamber area (P < 0.001), were significantly different among the four groups. Multivariate analysis showed anterior chamber depths: central, and anterior chamber depth at 2000 µm and anterior chamber area were higher in plateau iris and Thick peripheral iris roll and lower in exaggerated lens vault (P < 0.001) as compared to pupil block mechanism, lens vault was greater in exaggerated lens vault (P < 0.001) and lesser in plateau iris and Thick peripheral iris roll as compared to pupil block mechanism. CONCLUSION: Anterior segment optical coherence tomography may be used for evaluation of underlying primary angle closure mechanism(s) in a patient and tailor the treatment accordingly.
Assuntos
Câmara Anterior/patologia , Glaucoma de Ângulo Fechado/diagnóstico , Tomografia de Coerência Óptica , Idoso , Estudos Transversais , Feminino , Humanos , Pressão Intraocular/fisiologia , Iris/patologia , Cristalino/patologia , MasculinoRESUMO
PURPOSE: To use binocular integrated visual field (IVF) measures to predict which patients will lose visual function to a level below the legal standard for driving. METHODS: Data from patients attending a glaucoma clinic were collected longitudinally. The time from baseline until failure to meet the criteria of the driver's license test was modeled with Cox regression. Visual field status at baseline and visual field deterioration rate at 2 years from baseline for various monocular and binocular VF indices were investigated as predictor variables. The model that provided the best fit to the data was validated using bootstrap resampling. RESULTS: Of the patients, 20% (60/299; 95% confidence interval, 16%-25%) failed to meet the visual field criteria to prevent driver's license loss during an average follow-up of 7 years. The median age of patients was 64 years. The binocular IVF measurements gave a better fit to the observed data than the monocular measurements. Initial average visual field sensitivity and rate of visual field loss of sensitivity were significant predictors of failure to meet driver's license test criteria. CONCLUSIONS: The IVF provides a method by which binocular visual fields can be incorporated into patient management and allows, for example, a prediction of future driver's license loss. The rate of binocular IVF sensitivity loss at 2 years of follow-up may help identify patients who could benefit from intensified intervention.
Assuntos
Condução de Veículo/normas , Cegueira/diagnóstico , Avaliação da Deficiência , Glaucoma de Ângulo Aberto/fisiopatologia , Visão Binocular/fisiologia , Testes de Campo Visual/métodos , Campos Visuais/fisiologia , Condução de Veículo/legislação & jurisprudência , Cegueira/fisiopatologia , Diagnóstico por Computador/normas , Técnicas de Diagnóstico Oftalmológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Curva ROC , Inquéritos e Questionários , Reino Unido , Acuidade Visual/fisiologiaRESUMO
PURPOSE: To investigate the clinical features of subjects with glaucoma with the E50K mutation in the optineurin (OPTN) gene and to compare the onset, severity, and clinical course of these patients with a control group of subjects with glaucoma without this mutation. METHODS: The phenotype of well-characterized subjects from Moorfields Eye Hospital, London, who had been identified as carrying the OPTN E50K mutation was examined. A wide range of structural, psychophysical, and demographic factors were then compared with those in a control group of subjects with glaucoma without this mutation. RESULTS: Eleven subjects with glaucoma with the E50K mutation (nine in two families and two sporadic cases) were studied. All 11 subjects had normal tension glaucoma (NTG), with presenting and highest IOP of 15.3 +/- 3.0 and 16.5 +/- 2.5 mm Hg (+/-SD) on diurnal testing. Compared with 87 NTG control subjects who did not have this mutation, subjects with E50K presented at a younger age (40.8 +/- 15 years, P = 0.0001) and had more advanced optic disc cupping (mean cup-disc ratio +/- SD 0.86 +/- 0.1, P = 0.001) and smaller neuroretinal rim area (+/-SD; 0.5 +/- 0.28 mm2, P = 0.001) at diagnosis. The rate of filtration surgery performed for progressive visual field loss in those with and without the E50K mutation was 72.7% and 25.3%, respectively (P = 0.003), and all subjects with E50K were found to have progressing visual fields. In addition, seven E50K mutation-carrying individuals in two families (age range, 23-58 years) presented with normal optic discs and visual fields and, as yet, no signs of glaucoma. CONCLUSIONS: In this study, subjects with glaucoma who had the OPTN E50K mutation were found to have NTG that appeared to be more severe than that in a control group of subjects with NTG without this mutation. The findings emphasize the importance of early detection and treatment of glaucoma in such individuals, to minimize visual loss.
Assuntos
Glaucoma de Ângulo Aberto/diagnóstico , Glaucoma de Ângulo Aberto/genética , Mutação , Fator de Transcrição TFIIIA/genética , Adulto , Idoso , Proteínas de Ciclo Celular , Feminino , Cirurgia Filtrante , Glaucoma de Ângulo Aberto/cirurgia , Humanos , Pressão Intraocular , Masculino , Proteínas de Membrana Transportadoras , Pessoa de Meia-Idade , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Doenças do Nervo Óptico/genética , Linhagem , Fenótipo , Transtornos da Visão/diagnóstico , Transtornos da Visão/genética , Campos VisuaisRESUMO
PURPOSE: To determine and validate optimal parameters for analysis in a previously described approach for identifying glaucomatous optic nerve progression by scanning laser tomography. METHODS: Thirty-degree sectors of rim area, as defined by an experimental reference plane, were analyzed for change with respect to different statistical limits of variability (80%, 90%, 95%, 98%, 99%, and 99.9%) in the longitudinal image series of 62 eyes from 30 ocular hypertension converters and 32 normal control subjects. A criterion requiring that change is repeatable in two of three consecutive tests (the 2-of-3 criterion) was compared with a single-test strategy not requiring confirmation, and four other plausible criteria. The influence of these various parameters on sensitivity and the false-positive rate was evaluated. The same series were also assessed for change by the known method of computer-generated probability maps. RESULTS: More sectors were identified as progressing in converter eyes than in control eyes at every limit of variability. With stricter limits of variability and a requirement of confirmation, fewer sectors were identified as changing, especially in control eyes. The 2-of-3 criterion had the most favorably balanced sensitivity and false-positive rates: these were, for the 90% limit of variability, 90.0% and 6.2%, respectively, and for the 95% limit, 83.3% and 3.1%, respectively. Confirmed rim loss in converter eyes was most frequent in the disc poles and corresponded with the field hemisphere of conversion in 80%. Probability maps detected significant and repeatable change in 26 (86.7%) of 30 converter eyes and 14 (43.8%) of 32 of control eyes. CONCLUSIONS: This study was conducted to optimize and validate an approach for identifying progression. The method distinguished eyes with glaucomatous change from unchanging control eyes.
Assuntos
Técnicas de Diagnóstico Oftalmológico , Glaucoma/diagnóstico , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Adulto , Progressão da Doença , Glaucoma/fisiopatologia , Humanos , Pressão Intraocular , Lasers , Pessoa de Meia-Idade , Hipertensão Ocular/diagnóstico , Hipertensão Ocular/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Probabilidade , Tomografia , Testes de Campo VisualRESUMO
PURPOSE: To describe and evaluate a new experimental reference plane for measuring rim area in scanning laser tomography. METHODS: The experimental reference plane was positioned so that (1) it always lay entirely below the margin of the optic nerve head (ONH), (2) it remained at a set z-axis distance below the ONH in images of each eye, and (3) it was at a level where variability in rim area is least. Twenty normal control subjects and 20 patients with glaucoma underwent test-retest scanning laser tomographic imaging by same and different operators during same and separate visits. Control subjects had image series spanning at least 3 years. The effect of the positioning of the reference plane on global and regional rim area variability was assessed in intra- and intervisit test-retest images and longitudinal image series and compared with the standard and 320- microm reference planes. RESULTS: Variability in the experimental reference plane was less in test-retest images and longitudinal data (P < 0.05) and more uniform around the ONH than with other reference planes. Variability in the former was not appreciably affected by testing involving different operators and visits, or by the presence of glaucoma. CONCLUSIONS: Variability in rim area by the experimental reference plane was significantly less, more uniform around the ONH, not affected by different operators and visits, and less affected by glaucomatous morphology than other reference planes. This difference was pronounced in sequential data and has implications for detecting progression of glaucoma.
Assuntos
Técnicas de Diagnóstico Oftalmológico/normas , Glaucoma/diagnóstico , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Idoso , Feminino , Humanos , Lasers , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Tomografia/métodosRESUMO
PURPOSE: To describe and test an analytical approach for identifying glaucomatous optic nerve change by scanning laser tomography. METHODS: The approach (1). analyzed 30 degrees sectors of rim area by (2). a novel and reproducible experimental reference plane, (3). estimated and accounted for measurement variability in each sector, and (4). required that any change exceeding variability in a single (positive) test should be confirmed as repeatable by a criterion requiring two of three consecutive tests to be positive. The sensitivity and false-positive rate of a single positive test and the two-of-three criterion were assessed in image series of one eye each of 20 ocular hypertension patients who converted to glaucoma (referred to as converters) who had unambiguous disease progression, and in one eye each of 20 normal control subjects. RESULTS: Eighteen of 20 (90% sensitivity) converters and 7 of 20 (35% false-positive responses) control subjects had single positive test results, but with confirmation by the two-of-three criterion, the false-positive rate improved to 5% (1/20) whereas sensitivity was relatively preserved at 85% (17/20). CONCLUSIONS: Estimates of rim area variability in each sector of each nerve allowed change consistent with disease progression to be distinguished from measurement variability. Confirming that change is repeatable by the criterion used in the study resulted in considerably fewer false-positive responses than did testing without confirmation, but with sensitivity not significantly compromised in the former. By this approach, eyes with progressive glaucoma could be distinguished from unchanging normal control eyes.
Assuntos
Técnicas de Diagnóstico Oftalmológico , Glaucoma/diagnóstico , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Progressão da Doença , Reações Falso-Positivas , Glaucoma/fisiopatologia , Humanos , Pressão Intraocular , Lasers , Pessoa de Meia-Idade , Hipertensão Ocular/diagnóstico , Hipertensão Ocular/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia/métodosRESUMO
PURPOSE: To identify progressive rim loss and describe patterns of regional change in various clinical presentations of glaucoma by scanning laser tomography (SLT). METHODS: A previously described analytical approach was used to identify progressive rim area loss in SLT disc images of eyes of people with ocular hypertension (OHT, n = 97), early POAG (OHT converters; n = 30), asymmetric normal-pressure glaucoma (NPG, established and suspected in contralateral eyes; n = 26), and normal control subjects (n = 32). Analysis was performed longitudinally in individual image series, and cross-sectionally within groups at different time points. RESULTS: Reproducibly reduced rim area was detected in 2 (6.2%) of 32 normal control subjects, 11 (11%) of 97 OHT subjects, 27 (90%) of 30 OHT converters, 16 (58%) of 26 of suspected NPG eyes, and 15 (54%) of 26 of established NPG eyes (mean MD = -6.5 dB). Of 5 (19%) of 26 of suspected NPG eyes that converted on visual field testing, rim loss was detected in 3 of 5. In all groups, rim loss was common in the disc poles, especially inferiorly. Patterns of rim loss were similar within high-pressure and normal-pressure groups, whether or not eyes had field defects in each. In high-pressure groups, rim loss was more common nasally than temporally. Normal-pressure groups, unlike high-pressure groups, frequently had rim loss temporally. Suspected NPG eyes had more rim loss temporally and their rim area tended to be less compared with OHT and OHT converters, despite the three groups having equivalent baseline fields. CONCLUSIONS: There were similarities and differences in the pattern of rim loss in SLT disc images of high- and normal-pressure presentations of glaucoma. Progressive rim loss was detected in eyes without visual field defects, eyes that progressed to develop field defects, and eyes with established and more severe glaucoma.
Assuntos
Glaucoma de Ângulo Aberto/diagnóstico , Pressão Intraocular , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Retina/patologia , Adulto , Idoso , Estudos Transversais , Humanos , Lasers , Pessoa de Meia-Idade , Hipertensão Ocular/diagnóstico , Tomografia , Transtornos da Visão/diagnóstico , Campos VisuaisRESUMO
PURPOSE: To evaluate the relationship between electrophysiological, psychophysical, and structural measurements in normal and glaucomatous eyes and to test the hypothesis that there is a continuous structure-function relationship between ganglion cell numbers and visual field sensitivity. METHODS: Thirty-four normal subjects and 40 patients with glaucoma were examined with the pattern electroretinogram (PERG), perimetry and retinal tomography. Transient and steady state (SS) PERGs were recorded, and peak (P)-to-trough (N) amplitude was measured. The unit of differential light sensitivity (DLS) in perimetry is the decibel. The decibel is 10. log(1/Lambert), where the Lambert is the unit of test spot intensity. PERG amplitudes were correlated with decibel and 1/Lambert DLS for the central 18 degrees of the visual field and with neuroretinal rim area in the temporal part of the optic disc. Age-related changes in the structural and functional measurements were sought. The correlation between variables was investigated by linear and quadratic regression analysis. A quadratic (y = ax + bx(2) + c) fit was taken to be significantly better than a linear fit, if the coefficient (b) for the x(2) term was significant at P < 0.05. RESULTS: A quadratic fit between decibel DLS and PERG amplitude (transient PERG: R(2) = 0.40, P = 0.0000; SS PERG: R(2) = 0.32, P = 0.0000) was significantly better than a linear fit. There was a linear correlation between 1/Lambert DLS and PERG amplitude (transient PERG: R(2) = 0.44, P = 0.0000; SS PERG: R(2) = 0.35, P = 0.0000). There was a linear correlation between temporal neuroretinal rim area and PERG amplitude (transient PERG: R(2) = 0.17, P = 0.0003; SS PERG: R(2) = 0.20, P = 0.0001). A quadratic fit between decibel DLS and temporal neuroretinal rim area (R(2) = 0.38, P = 0.0000) was significantly better than a linear fit. There was a linear correlation between 1/Lambert DLS and temporal neuroretinal rim area (R(2) = 0.30, P = 0.0000). Both DLS and PERG amplitude declined with age in the normal subjects. The rate of decline was -0.17%, -0.74%, -0.75%, and -0.78% per year for decibel DLS, 1/Lambert DLS, transient PERG, and SS PERG, respectively. CONCLUSIONS: There is a curvilinear relationship between decibel DLS and both PERG amplitude and neuroretinal rim area, and a linear relationship between 1/Lambert DLS and PERG amplitude and neuroretinal rim area. These findings support the hypothesis that there is no ganglion cell functional reserve but a continuous structure-function relationship, and that the impression of a functional reserve results from the logarithmic (decibel) scaling of the visual field.
Assuntos
Glaucoma de Ângulo Aberto/fisiopatologia , Células Ganglionares da Retina/patologia , Transtornos da Visão/fisiopatologia , Campos Visuais , Idoso , Contagem de Células , Eletrorretinografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/fisiopatologia , Reconhecimento Visual de Modelos , Estudos Prospectivos , Psicofísica , Testes de Campo VisualRESUMO
PURPOSE: To determine reasons for rim area variability in scanning laser tomography. METHODS: Regional rim area variability from testing in same and different visits and by same and different observers was characterized in 30 normal and 42 glaucomatous eyes. Variations in (1) optic nerve head (ONH) surface geometry (center of gravity: X, Y, Z), (2) image tilting (horizontally and vertically), and (3) position of the reference plane in relation to the ONH (REF) were analyzed by multiple regression analysis. Whether and how much these factors explain rim area variability was studied in cross-sectional and longitudinal data by using two different reference planes. RESULTS: Variability was higher in glaucoma and in testing by different observers in separate visits. Across a range of eyes, approximately 40% of variability in single-topography images and 60% of variability in mean-topography images was explained. In individual image series, a median 85% of variability was explained, exceeding 90% in at least 25% of eyes. The most frequent contributors to rim area variability were REF (in > or =95%) and Z (in > or =80%); they also usually explained more variability than other factors. The nature of variability differed between reference planes. CONCLUSIONS: A large proportion of rim area variability was explained by variation in the topographical features studied, especially REF and Z. Reference plane definition also influenced variability. Variation in the position of the reference plane in relation to the ONH can affect rim area measurements and should be considered when evaluating the progression of glaucoma.
Assuntos
Técnicas de Diagnóstico Oftalmológico/normas , Glaucoma/diagnóstico , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Idoso , Feminino , Humanos , Pressão Intraocular , Lasers , Masculino , Reprodutibilidade dos Testes , Tomografia/métodosRESUMO
PURPOSE: Mutations in murine and human versions of an ancestrally related gene usually result in similar phenotypes. However, interspecies differences exist, and in the case of two forkhead transcription factor genes (FOXC1 and FOXC2), these differences include corneal or anterior segment phenotypes, respectively. This study was undertaken to determine whether such discrepancies provide an opportunity for identifying novel human-murine ocular phenotypes. METHODS: Four pedigrees with early-onset glaucoma phenotypes secondary to segmental chromosomal duplications or deletions encompassing FOXC1 and 18 individuals from 9 FOXC2 mutation pedigrees underwent detailed ocular phenotyping. Subsequently, mice with mutations in Foxc1 or a related forkhead gene, Foxe3, were assessed for features of the human phenotypes. RESULTS: A significant increase in central corneal thickness was present in affected individuals from the segmental duplication pedigrees compared with their unaffected relatives (mean increase 13%, maximum 35%, P < 0.05). Alterations in corneal thickness were present in mice heterozygous and homozygous for Foxe3 mutations but neither in Foxc1 heterozygotes nor the small human segmental deletion pedigree. Mutations in FOXC2 resulted in ocular anterior segment anomalies. These were more severe and prevalent with mutations involving the forkhead domain. CONCLUSIONS: Normal corneal development is dependent on the precise dose and levels of activity of certain forkhead transcription factors. The altered corneal thickness attributable to increased forkhead gene dosage is particularly important, because it may affect the clinical management of certain glaucoma subtypes and lead to excessive treatment. The FOXC1 and Foxe3 data, taken together with the novel ocular phenotypes of FOXC2 mutations, highlight the remarkable cross-species conservation of function among forkhead genes.
Assuntos
Segmento Anterior do Olho/anormalidades , Proteínas de Ligação a DNA/genética , Anormalidades do Olho/genética , Glaucoma/genética , Fatores de Transcrição/genética , Animais , Segmento Anterior do Olho/patologia , Córnea/anormalidades , Córnea/patologia , Proteínas de Ligação a DNA/fisiologia , Anormalidades do Olho/patologia , Fatores de Transcrição Forkhead , Humanos , Pressão Intraocular/genética , Iris/anormalidades , Iris/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mutação , Linhagem , Fatores de Transcrição/fisiologiaRESUMO
PURPOSE: Mutations in the forkhead transcription factor gene FOXC1 on 6p25 cause a range of ocular developmental abnormalities, with associated glaucoma. However, FOXC1 mutations have not been found in all similarly affected pedigrees mapping to this interval. This study was undertaken to investigate the potential role of 6p25 rearrangements in causing such phenotypes. METHODS: Two large families with autosomal dominant iris hypoplasia and early-onset glaucoma, 21 probands with Axenfeld-Rieger phenotypes not attributable to PITX2 mutations, and 7 individuals with documented 6p25 cytogenetic rearrangements, were investigated by genotyping and fluorescence in situ hybridization, with markers and probes from the 6p25 region. RESULTS: Interstitial 6p25 duplications were present in the unrelated families with iris hypoplasia, whereas an interstitial 6p25 deletion was identified in one Axenfeld-Rieger pedigree. Larger cytogenetic rearrangements, leading to trisomy or monosomy of the 6p25 region, resulted in microcornea and Rieger syndrome phenotypes, respectively. All the rearrangements encompassed FOXC1, increasing or decreasing the number of FOXC1 copies present, and appeared to correlate with the phenotypes observed. CONCLUSIONS: These findings represent the first example of both interstitial duplications and deletions cosegregating with a human developmental disorder that is attributable to altered dose of transcription factor. The data presented provide additional evidence for the pathogenicity of altered gene dosage of FOXC1 and suggest that a common mechanism is responsible for rearrangements of 6p25.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 6/genética , Córnea/anormalidades , Proteínas de Ligação a DNA , Anormalidades do Olho/genética , Duplicação Gênica , Glaucoma/genética , Iris/anormalidades , Sequência de Bases , Mapeamento de Sequências Contíguas , Feminino , Fatores de Transcrição Forkhead , Rearranjo Gênico , Genótipo , Humanos , Hibridização in Situ Fluorescente , Masculino , Microscopia de Fluorescência , Dados de Sequência Molecular , Linhagem , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: Over the past decade, several new medical therapies have become available for the treatment of primary open-angle glaucoma (POAG). A systematic evidence-based approach for identifying an optimal therapeutic agent is lacking. OBJECTIVES: The aims of this review were to critically evaluate published treatment recommendations for POAG and, based on a systematic review of the literature, to develop criteria that would define a "gold standard" medical therapy that reflects new treatment advances and established therapeutic goals. METHODS: A MEDLINE search spanning the years 1966 to 2002 and using the search terms gold standard, drug of choice, agent of choice, benchmark, ophthalmology, eye, and glaucoma was conducted and the results reviewed by a panel of 15 experts in the field of glaucoma. Published treatment recommendations for POAG were discussed. Criteria, anchored to medical evidence, for distinguishing a standard of medical therapy for POAG were defined. RESULTS: The terms connoting a gold standard therapy were found in only 258 of approximately 368,000 ophthalmology-related citations and 53 of almost 23,000 glaucoma citations, validating the need to define therapeutic standards. The lack of recommendations for the use of new classes of ocular hypotensive agents was acknowledged. Criteria identified to evaluate intraocular pressure (IOP)-lowering agents as gold standards included the following: efficacy in reducing IOP consistently over a 24-hour period to a level that will preserve the visual field and protect the optic nerve without inducing tachyphylaxis and tolerance, paucity of local and systemic adverse effects, promotion of patient compliance, and applicability in diverse patient populations. CONCLUSIONS: These criteria should be employed as measures for evidence-based analyses to evaluate available and future IOP-lowering medical therapies for POAG. The conceptual framework presented may be applicable to other therapeutic areas.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Benchmarking/métodos , Medicina Baseada em Evidências , Glaucoma de Ângulo Aberto/tratamento farmacológico , Oftalmologia/normas , Doença Crônica , Humanos , Cooperação do Paciente , Qualidade de VidaRESUMO
Visual field testing with automated perimetry is hampered by the amount of noise present in the readings. Here, we derive a physiologically accurate spatial filter to be applied to the data after patient examination. The filter was tested by a Virtual Eye computer simulation. By simulating series of stable fields it was shown that specificity of determining visual field changes was improved; while simulating progressing fields (based on a map of the optic nerve head) it was shown that sensitivity was also improved. The filter appears to reduce the noise in glaucomatous visual field data and may be clinically useful.
Assuntos
Simulação por Computador , Processamento Eletrônico de Dados , Glaucoma/diagnóstico , Testes de Campo Visual/métodos , Bases de Dados Factuais , Glaucoma/fisiopatologia , Humanos , Disco Óptico/fisiopatologia , Sensibilidade e Especificidade , Campos VisuaisRESUMO
PURPOSE: To identify and characterize 'reversal' of optic nerve cupping following intraocular pressure (IOP) lowering in scanning laser tomography (SLT) longitudinal image series. METHODS: Modification was made to a previously described analytical approach to longitudinally study putatively increased rim area following IOP lowering. Sustained IOP reduction of 25% was by topical medication. Forty SLT image series with equivalent follow up were assessed: 10 with ocular hypertension (OHT), 10 with primary open angle glaucoma (POAG), and as controls, 20 normal. Reproducible rim area reversal was identified by sector and its time-course over 1 year examined. RESULTS: By a 2-of-3 reproducibility criterion, reversal following IOP lowering was confirmed in about a third of treated eyes (POAG and OHT) but not in any controls. Rim sectors showing reversal were mostly nasal, with a few occurring superotemporally. Reversal in a fifth of treated eyes persisted for at least 1 year; all these were in the nasal half of the disc. The number of sectors with persisting reversal affected less than 6% of all treated eyes' rim sectors. CONCLUSION: Rim area is not uncommonly increased after IOP lowering and this 'reversal' may persist for at least a year. Within topically treated eyes having IOP lowering of at least 25%, the proportion of rim sectors with persistent reversal appears small. Nevertheless, the effects of IOP reduction on topography, especially in the short term, should be considered when longitudinally assessing progressive rim loss in SLT images.
Assuntos
Glaucoma de Ângulo Aberto/diagnóstico , Glaucoma de Ângulo Aberto/fisiopatologia , Pressão Intraocular , Disco Óptico/patologia , Idoso , Glaucoma de Ângulo Aberto/tratamento farmacológico , Humanos , Pressão Intraocular/efeitos dos fármacos , Lasers , Latanoprosta , Levobunolol/uso terapêutico , Pessoa de Meia-Idade , Hipertensão Ocular/diagnóstico , Hipertensão Ocular/tratamento farmacológico , Hipertensão Ocular/fisiopatologia , Prostaglandinas F Sintéticas/uso terapêutico , Reprodutibilidade dos Testes , Estudos Retrospectivos , TomografiaRESUMO
PURPOSE: Reference plane description of the neuroretinal rim in scanning laser tomography should correctly represent optic nerve morphology. We evaluated how well rim area analysis by different reference planes agreed with the appearance of rim area in disc images. METHODS: Three expert observers subjectively and repeatedly analyzed rim area in Heidelberg Retina Tomograph (HRT) images so that each optic disc was measured six times in 100 eyes, 50 normal and 50 glaucoma. Rim area was evaluated globally and in 30 degree sectors. Agreement between rim appearance, as subjectively analyzed, and objective analysis by an experimental reference plane, the standard reference plane, and a reference plane fixed 320 microm below the reference ring was assessed in HRT images. RESULTS: Subjective analysis of rim area in HRT images was consistent between expert observers. Their analysis of rim appearance agreed more closely with experimental reference plane analysis than analysis by the standard or 320-microm reference planes; this was true globally and in every region of the nerve (P = 0.000). The experimental reference plane yielded higher estimates of rim area than did the standard or 320-microm reference planes. CONCLUSION: There was closer correspondence between the appearance of the neuroretinal rim in images and description by the experimental reference plane compared with description by the standard and 320-microm reference planes.
Assuntos
Glaucoma/diagnóstico , Processamento de Imagem Assistida por Computador , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Idoso , Humanos , Lasers , Oftalmoscopia , Reprodutibilidade dos TestesRESUMO
PURPOSE: It is important when evaluating glaucomatous optic disc progression in longitudinal images that image magnification remains unchanged. We studied the effect of changed lens power on magnification in scanning laser tomography. The relative contribution to magnification of axial length, eye-scanner distance, and image-to-image scaling was also assessed. METHODS: A simulated optic disc in a model eye was imaged using the Heidelberg Retina Tomograph. Lens power was alterable by exchanging intraocular lenses (IOL) mounted at the lens plane of the eye to mimic changes in the crystalline lens. IOL power of +20.0D and axial length of 21.5 mm was compatible with emmetropia. The optic disc was imaged through IOLs differing in power (+16.0D to +25.0D) but with axial length kept constant. IOL power was then held constant and imaging was repeated for various axial lengths (17.5-23.5 mm). Model eye-scanner distance was varied with each test sequence. The distances between landmarks on the disc was measured before and after contour lines were exported. RESULTS: Image size varied with IOL power and axial length (r > 0.98; P < 0.0001), with the magnification effect of a +1D increase in lens power equivalent to a third the magnification effect of a 1-mm increase in axial length. Magnification tended to increase with myopia (IOL power > +20.0D) and was accentuated by longer eye-scanner distances. Image-to-image scaling corrected some magnification though this varied with ametropia. CONCLUSIONS: Changed lens power, axial length, and eye-scanner distance can affect the size of the optic disc in scanning laser tomography images. The exported contour line partly compensates for changed magnification.
Assuntos
Glaucoma/diagnóstico , Lasers , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Tomografia/métodos , Progressão da Doença , Humanos , Modelos Biológicos , Oftalmoscopia/métodosRESUMO
PURPOSE: To compare the results of intraocular pressure (IOP) reduction by 3 treatment modalities, (a) glaucoma tube implants, (b) noncontact YAG laser cyclophotocoagulation (cycloYAG), and (c) contact transscleral diode laser cyclophotocoagulation (cyclodiode), in cases of advanced glaucoma refractory to alternative treatments. METHODS: A consecutive group of 45 eyes that received cycloYAG were matched against two control groups of patients who had received tube surgery or cyclodiode, each control group having been derived from a database of patients. RESULTS: Mean pretreatment IOP improved from 41.3, 38.6, and 32.0 mmHg for the tube, cycloYAG, and cyclodiode groups, respectively, to 16.4, 22.1, and 19.3 mmHg, respectively. Treatment success was achieved in 78%, 69%, and 71% of the tube, cycloYAG, and cyclodiode groups, respectively. Visual acuity deteriorated 2 or more Snellen lines in 16%, 7%, and 9% of the patients in the tube, cycloYAG, and cyclodiode groups, respectively. Complications included retinal detachment, hypotony, and phthisis. CONCLUSIONS: All 3 methods provided acceptable IOP lowering in the short and medium term. Control of IOP was best in patients receiving tube surgery. Cyclodiode and cycloYAG treatments were similarly effective in lowering IOP. Tube surgery was associated with a greater incidence of sight threatening complications.
Assuntos
Corpo Ciliar/cirurgia , Glaucoma/cirurgia , Lasers Semicondutores , Fotocoagulação , Adulto , Feminino , Glaucoma/patologia , Humanos , Pressão Intraocular , Masculino , Resultado do TratamentoRESUMO
PURPOSE: Measures of quality of life called utility values (UVs) are needed to deliver the most cost-effective health care for glaucoma patients. UVs are rarely measured in clinical research and practice whereas clinical outcomes such as visual field are routinely collected. The aim of this study was to develop an algorithm that calculates UVs directly from combinations of routine measures of binocular visual field, visual acuity, and contrast sensitivity. METHODS: A total of 132 outpatients with primary open angle glaucoma were recruited. The Time Trade-off (TTO) question was administered during face-to-face interviews. Binocular ETDRS logMAR visual acuity (VA(B)), binocular Pelli-Robson contrast sensitivity (CS(B)), and Humphrey 24-2 monocular visual field tests were performed on the same day. Integrated (binocular) visual field (IVF) scores were derived. Tobit regression analyses were used to model utility values based on combinations of IVF, VA(B), CS(B) and other controlling factors. RESULTS: UVs recorded for 123 cases correlated significantly with both clinical measures of binocular visual function (r = -0.47, IVF; r = -0.48, VA(B); r = 0.50, CS(B); P <0.0001) and measures of vision-specific quality of life (r = 0.54-0.6, P <0.0001). Two final models incorporate terms for IVF and VA(B), with or without living arrangements, and explain 22% and 31% of variation in utilities. CS(B) was not included in either model due to co-linearity between CS(B) and VA(B) confounding the models. CONCLUSION: The models provide preliminary algorithms for predicting the expected UVs for glaucoma populations directly from clinical outcomes collected routinely in clinical practice.
Assuntos
Algoritmos , Glaucoma/fisiopatologia , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Sensibilidades de Contraste/fisiologia , Avaliação da Deficiência , Feminino , Glaucoma/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Acuidade Visual/fisiologia , Campos Visuais/fisiologiaAssuntos
Competência Clínica/normas , Avaliação Educacional , Glaucoma , Oftalmologia/normas , Padrões de Prática Médica/normas , Especialização/normas , Conselhos de Especialidade Profissional , Currículo , Educação de Pós-Graduação em Medicina , Europa (Continente) , Bolsas de Estudo , Glaucoma/terapia , Humanos , Internato e Residência , Oftalmologistas/educação , Oftalmologistas/normas , Oftalmologia/educação , Sociedades MédicasRESUMO
PURPOSE: To test the hypothesis that there is a major genetic determinant of vertical disc diameter (VDD) and vertical cup-to-disc ratio (VCDR) in a large, population-based sample. METHODS: Data were collected from 3654 individuals, 49 years of age or older, participating in the Blue Mountains Eye Study. VDD and VCDR were determined from stereo optic disc photographs. Commingling analyses in SKUDRIVER/SKUMIX were performed in nonglaucomatous eyes to investigate whether the observed VDD and VCDR data were best described by a one-, two-, or three-distribution model. RESULTS: VDD data did not show evidence of commingling. After adjustment for the effects of age, VDD and intraocular pressure, the best model for VCDR consisted of a mixture of three distributions in Hardy-Weinberg equilibrium. The proportion of the variance in VCDR explained by this mixing component was 0.58. CONCLUSIONS: Findings from this study are consistent with the presence of a major gene that accounts for 58% of the variance in VCDR. These results strongly support further efforts to identify the genetic variants responsible for this quantitative trait, which is a key constituent of the phenotype of primary open-angle glaucoma (POAG).