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1.
PLoS One ; 13(12): e0207784, 2018.
Article in English | MEDLINE | ID: mdl-30517157

ABSTRACT

PURPOSE: To test the ability of machine learning classifiers (MLCs) using optical coherence tomography (OCT) and standard automated perimetry (SAP) parameters to discriminate between healthy and glaucomatous individuals, and to compare it to the diagnostic ability of the combined structure-function index (CSFI), general ophthalmologists and glaucoma specialists. DESIGN: Cross-sectional prospective study. METHODS: Fifty eight eyes of 58 patients with early to moderate glaucoma (median value of the mean deviation = -3.44 dB; interquartile range, -6.0 to -2.4 dB) and 66 eyes of 66 healthy individuals underwent OCT and SAP tests. The diagnostic accuracy (area under the ROC curve-AUC) of 10 MLCs was compared to those obtained with the CSFI, 3 general ophthalmologists and 3 glaucoma specialists exposed to the same OCT and SAP data. RESULTS: The AUCs obtained with MLCs ranged from 0.805 (Classification Tree) to 0.931 (Radial Basis Function Network, RBF). The sensitivity at 90% specificity ranged from 51.6% (Classification Tree) to 82.8% (Bagging, Multilayer Perceptron and Support Vector Machine Gaussian). The CSFI had a sensitivity of 79.3% at 90% specificity, and the highest AUC (0.948). General ophthalmologists and glaucoma specialists' grading had sensitivities of 66.2% and 83.8% at 90% specificity, and AUCs of 0.879 and 0.921, respectively. RBF (the best MLC), the CSFI, and glaucoma specialists showed significantly higher AUCs than that obtained by general ophthalmologists (P<0.05). However, there were no significant differences between the AUCs obtained by RBF, the CSFI, and glaucoma specialists (P>0.25). CONCLUSION: Our findings suggest that both MLCs and the CSFI can be helpful in clinical practice and effectively improve glaucoma diagnosis in the primary eye care setting, when there is no glaucoma specialist available.


Subject(s)
Algorithms , Diagnosis, Computer-Assisted , Glaucoma/diagnosis , Cross-Sectional Studies , Female , Glaucoma, Open-Angle/diagnosis , Humans , Male , Middle Aged , Ophthalmologists , Primary Health Care , Prospective Studies , ROC Curve , Supervised Machine Learning , Tomography, Optical Coherence , Visual Field Tests
2.
Arq Bras Oftalmol ; 75(1): 53-8, 2012.
Article in English | MEDLINE | ID: mdl-22552419

ABSTRACT

PURPOSE: To evaluate the retinal nerve fiber layer measurements with time-domain (TD) and spectral-domain (SD) optical coherence tomography (OCT), and to test the diagnostic ability of both technologies in glaucomatous patients with asymmetric visual hemifield loss. METHODS: 36 patients with primary open-angle glaucoma with visual field loss in one hemifield (affected) and absent loss in the other (non-affected), and 36 age-matched healthy controls had the study eye imaged with Stratus-OCT (Carl Zeiss Meditec Inc., Dublin, California, USA) and 3 D OCT-1000 (Topcon, Tokyo, Japan). Peripapillary retinal nerve fiber layer measurements and normative classification were recorded. Total deviation values were averaged in each hemifield (hemifield mean deviation) for each subject. Visual field and retinal nerve fiber layer "asymmetry indexes" were calculated as the ratio between affected versus non-affected hemifields and corresponding hemiretinas. RESULTS: Retinal nerve fiber layer measurements in non-affected hemifields (mean [SD] 87.0 [17.1] µm and 84.3 [20.2] µm, for TD and SD-OCT, respectively) were thinner than in controls (119.0 [12.2] µm and 117.0 [17.7] µm, P<0.001). The optical coherence tomography normative database classified 42% and 67% of hemiretinas corresponding to non-affected hemifields as abnormal in TD and SD-OCT, respectively (P=0.01). Retinal nerve fiber layer measurements were consistently thicker with TD compared to SD-OCT. Retinal nerve fiber layer thickness asymmetry index was similar in TD (0.76 [0.17]) and SD-OCT (0.79 [0.12]) and significantly greater than the visual field asymmetry index (0.36 [0.20], P<0.001). CONCLUSIONS: Normal hemifields of glaucoma patients had thinner retinal nerve fiber layer than healthy eyes, as measured by TD and SD-OCT. Retinal nerve fiber layer measurements were thicker with TD than SD-OCT. SD-OCT detected abnormal retinal nerve fiber layer thickness more often than TD-OCT.


Subject(s)
Glaucoma, Open-Angle/diagnosis , Nerve Fibers/pathology , Visual Fields/physiology , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Glaucoma, Open-Angle/physiopathology , Humans , Male , Middle Aged , Tomography, Optical Coherence , Visual Field Tests
3.
Arq. bras. oftalmol ; 75(1): 53-58, jan.-fev. 2012. tab
Article in English | LILACS | ID: lil-622547

ABSTRACT

PURPOSE: To evaluate the retinal nerve fiber layer measurements with time-domain (TD) and spectral-domain (SD) optical coherence tomography (OCT), and to test the diagnostic ability of both technologies in glaucomatous patients with asymmetric visual hemifield loss. METHODS: 36 patients with primary open-angle glaucoma with visual field loss in one hemifield (affected) and absent loss in the other (non-affected), and 36 age-matched healthy controls had the study eye imaged with Stratus-OCT (Carl Zeiss Meditec Inc., Dublin, California, USA) and 3 D OCT-1000 (Topcon, Tokyo, Japan). Peripapillary retinal nerve fiber layer measurements and normative classification were recorded. Total deviation values were averaged in each hemifield (hemifield mean deviation) for each subject. Visual field and retinal nerve fiber layer "asymmetry indexes" were calculated as the ratio between affected versus non-affected hemifields and corresponding hemiretinas. RESULTS: Retinal nerve fiber layer measurements in non-affected hemifields (mean [SD] 87.0 [17.1] µm and 84.3 [20.2] µm, for TD and SD-OCT, respectively) were thinner than in controls (119.0 [12.2] µm and 117.0 [17.7] µm, P<0.001). The optical coherence tomography normative database classified 42% and 67% of hemiretinas corresponding to non-affected hemifields as abnormal in TD and SD-OCT, respectively (P=0.01). Retinal nerve fiber layer measurements were consistently thicker with TD compared to SD-OCT. Retinal nerve fiber layer thickness asymmetry index was similar in TD (0.76 [0.17]) and SD-OCT (0.79 [0.12]) and significantly greater than the visual field asymmetry index (0.36 [0.20], P<0.001). CONCLUSIONS: Normal hemifields of glaucoma patients had thinner retinal nerve fiber layer than healthy eyes, as measured by TD and SD-OCT. Retinal nerve fiber layer measurements were thicker with TD than SD-OCT. SD-OCT detected abnormal retinal nerve fiber layer thickness more often than TD-OCT.


OBJETIVO: Avaliar as medidas da camada de fibras nervosas da retina com a tomografia de coerência óptica (OCT) "time domain" (TD) e "spectral domain" (SD), e testar a habilidade diagnóstica de ambas as tecnologias em pacientes com perda assimétrica glaucomatosa de hemicampo visual. MÉTODOS: Trinta e seis pacientes com glaucoma primário de ângulo aberto com perda de campo visual em um hemicampo (acometido) e ausência de perda no hemicampo oposto (não-acometido), e 36 controles pareados por idade tiveram o olho de estudo examinado com Stratus-OCT (Carl Zeiss Meditec Inc., Dublin, California, USA) e 3 D OCT-1000 (Topcon, Tokyo, Japan). As medidas de espessura da camada de fibras nervosas da retina peripapilar e classificação normativa fornecida pelos aparelhos foram registrados para análise. A média aritmética dos valores do gráfico de desvio total em cada hemicampo foi calculada para cada indivíduo. "Índices de assimetria" para campo visual e camada de fibras nervosas da retina foram calculados como a razão entre hemicampos acometido e não-acometido e hemirretinas correspondentes, respectivamente. RESULTADOS: As medidas da camada de fibras nervosas da retina em hemicampos não-acometidos (média [SD] 87.0 [17.1] µm e 84.3 [20.2] µm, para TD e SD-OCT, respectivamente) foram menores do que em controles (119.0 [12.2] µm e 117.0 [17.7] µm, P<0.001). O banco de dados normativo classificou como alterado 42% e 67% das hemirretinas correspondentes a hemicampos não-acometidos com TD e SD-OCT, respectivamente (P=0.01). As medidas da camada de fibras nervosas da retina foram consistentemente mais espessas com TD comparados com SD-OCT. Índices de assimetria da camada de fibras nervosas da retina foram semelhantes entre TD (0.76 [0.17]) e SD-OCT (0.79 [0.12]) e significantemente maiores do que o índice de assimetria do campo visual (0.36 [0.20], P<0.001). CONCLUSÃO: Os hemicampos normais de pacientes com glaucoma apresentaram camada de fibras nervosas da retina mais fina do que olhos saudáveis. As medidas da camada de fibras nervosas da retina foram mais espessas com TD do que com SD-OCT, que por sua vez detectou anormalidades na espessura da camada de fibras nervosas da retina mais frequentemente do que o TD-OCT.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Glaucoma, Open-Angle/diagnosis , Nerve Fibers/pathology , Visual Fields/physiology , Case-Control Studies , Glaucoma, Open-Angle/physiopathology , Tomography, Optical Coherence , Visual Field Tests
4.
Arq Bras Oftalmol ; 74(1): 61-3, 2011.
Article in English | MEDLINE | ID: mdl-21670912

ABSTRACT

A 55-year-old woman was referred to our clinic because of a one-week history of visual loss and raised intraocular pressure in the left eye followed 4 days later by visual loss in the right eye. Slit-lamp examination showed bilateral conjunctival hyperemia, slight diffuse corneal edema, shallow anterior chamber and fixed and dilated pupil in both eyes. Splitting of the anterior layers of the iris with fibrillar degeneration extending for approximately one quadrant inferiorly was presented in each eye. Fundus examination showed optic disc edema with no vascular tortuosity and no cup in both eyes. The condition was treated as bilateral acute angle-closure glaucoma in a patient with irisdoschisis. After medical treatment and improvement of visual acuity, perimetry revealed a significant visual field defect especially in left eye; this case represents a rare concurrence of acute angle-closure glaucoma and bilateral nonarteritic ischemic optic neuropathy. Although most cases of elevated intraocular pressure, including acute angle-closure glaucoma, do not result in optic disc edema and irreversible vision loss, variations in the vascular supply of the nerve optic head along with others ocular systemic risk factors, may predispose certain individuals to nonarteritic ischemic optic neuropathy during periods of elevated intraocular pressure.


Subject(s)
Glaucoma, Angle-Closure/complications , Iris Diseases/complications , Optic Neuropathy, Ischemic/complications , Female , Glaucoma, Angle-Closure/surgery , Humans , Iris Diseases/surgery , Microscopy, Acoustic , Middle Aged , Optic Neuropathy, Ischemic/surgery
5.
Arq. bras. oftalmol ; 74(1): 61-63, Jan.-Feb. 2011. ilus
Article in English | LILACS | ID: lil-589943

ABSTRACT

A 55-year-old woman was referred to our clinic because of a one-week history of visual loss and raised intraocular pressure in the left eye followed 4 days later by visual loss in the right eye. Slit-lamp examination showed bilateral conjunctival hyperemia, slight diffuse corneal edema, shallow anterior chamber and fixed and dilated pupil in both eyes. Splitting of the anterior layers of the iris with fibrillar degeneration extending for approximately one quadrant inferiorly was presented in each eye. Fundus examination showed opitc disc edema with no vascular tortuosity and no cup in both eyes. The condition was treated as bilateral acute angle-closure glaucoma in a patient with irisdoschisis. After medical treatment and improvement of visual acuity, perimetry revealed a significant visual field defect especially in left eye; this case represents a rare concurrence of acute angle-closure glaucoma and bilateral nonarteritic ischemic optic neuropathy. Although most cases of elevated intraocular pressure, including acute angle-closure glaucoma, do not result in optic disc edema and irreversible vision loss, variations in the vascular supply of the nerve optic head along with others ocular systemic risk factors, may predispose certain individuals to nonarteritic ischemic optic neuropathy during periods of elevated intraocular pressure.


Paciente de 55 anos, sexo feminino, encaminhada para nosso serviço com história de perda de visão e aumento da pressão intraocular no olho esquerdo há uma semana seguida quatro dias após de perda visual no olho direito. À biomicroscopia hiperemia conjuntival bilateral, edema difuso da córnea, câmara anterior rasa e pupilas fixas e dilatadas em ambos os olhos. Separação do folheto anterior da íris no quadrante inferior estava presente em ambos os olhos. O exame do fundo do olho mostrava edema de disco sem tortuosidade vascular e sem escavação em ambos os olhos. O quadro clínico foi tratado como crise de fechamento angular bilateral num paciente com iridosquise. Após tratamento clínico e iridotomia bilateral com melhora da acuidade visual, a perimetria computadorizada revelou grave perda de campo visual, especialmente no olho esquerdo; este caso representa a rara ocorrência simultânea de crise de fechamento angular e neuropatia óptica isquêmica anterior não-arterítica bilateral. Embora a maioria dos casos com pressão intraocular elevada, incluindo crise de fechamento angular, não resulta em edema de disco e perda visual irreverssível, variações no suprimento vascular da cabeça do nervo óptico associados com outros fatores de risco sistêmicos, podem predispor certos indivíduos à neuropatia óptica isquêmica anterior durante períodos de elevação da pressão intraocular.


Subject(s)
Female , Humans , Middle Aged , Glaucoma, Angle-Closure/complications , Iris Diseases/complications , Optic Neuropathy, Ischemic/complications , Glaucoma, Angle-Closure/surgery , Iris Diseases/surgery , Microscopy, Acoustic , Optic Neuropathy, Ischemic/surgery
6.
J Ocul Pharmacol Ther ; 25(5): 447-51, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19860553

ABSTRACT

INTRODUCTION AND PURPOSE: Bimatoprost and the fixed combination of latanoprost with timolol maleate are 2 medications widely used to treat glaucoma and ocular hypertension (OHT). The aim of the study is to compare the efficacy of these 2 drugs in reducing intraocular pressure (IOP) after 8 weeks of treatment in patients with primary open angle glaucoma (POAG) or OHT. METHODS: In this randomized, open-label trial, 44 patients with POAG or OHT were allocated to receive either bimatoprost (1 drop QD) or latanoprost/timolol (1 drop QD). Primary outcome was the mean diurnal IOP measurement at the 8th week, calculated as the mean IOP measurements taken at 8:00 am, 10:00 am, and 12:00 pm Secondary outcomes included the baseline change in IOP measured 3 times a day, after the water-drinking test (performed after the last IOP measurement), and the assessment of side effects of each therapy. RESULTS: The mean IOP levels of latanoprost/timolol (13.83, SD = 2.54) was significantly lower than of bimatoprost (16.16, SD = 3.28; P < 0.0001) at week 8. Also, the change in mean IOP values was significantly higher in the latanoprost/timolol group at 10:00 am (P = 0.013) and 12:00 pm (P = 0.01), but not at 8:00 am (P = ns). During the water-drinking test, there was no significant difference in IOP increase (absolute and percentage) between groups; however, there was a significant decrease in mean heart rate in the latanoprost/timolol group. Finally, no significant changes in blood pressure and lung spirometry were observed in either groups. CONCLUSIONS: The fixed combination of latanoprost/timolol was significantly superior to bimatoprost alone in reducing IOP in patients with POAG or OHT. Further studies with large sample sizes should be taken to support the superior efficacy of latanoprost/timolol, as well as to better assess its profile of side effects.


Subject(s)
Amides/therapeutic use , Antihypertensive Agents/therapeutic use , Cloprostenol/analogs & derivatives , Glaucoma, Open-Angle/drug therapy , Intraocular Pressure/drug effects , Prostaglandins F, Synthetic/therapeutic use , Timolol/therapeutic use , Bimatoprost , Blood Pressure/drug effects , Cloprostenol/therapeutic use , Drug Combinations , Female , Heart Rate/drug effects , Humans , Latanoprost , Male , Middle Aged , Ocular Hypertension/drug therapy , Ophthalmic Solutions
7.
Clin Exp Ophthalmol ; 37(3): 270-4, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19472536

ABSTRACT

PURPOSE: The aim of this paper is to study the correlation between the intraocular pressure peaks and fluctuation detected during the water drinking test and the same parameters observed during long-term follow up. METHODS: This prospective cohort study enrolled 22 eyes of 22 newly diagnosed primary open angle glaucoma patients. After an initial complete ophthalmological examination, patients were started on antiglaucoma medication and returned 4 weeks later to perform the water drinking test. Thereafter,patients were evaluated at least eight times within a period of 6-12 months. The intraocular pressure peaks and fluctuation detected during the water drinking stress test were compared with those observed during regular office visits. Spearman's correlation coefficient and Bland-Altman Plots were used for statistical analysis. RESULTS: The mean age of participants was 54.3 +/- 8.2 years (+/-SD), 59% were women, and average mean deviation -10.2 +/- 4.5 dB. The mean follow-up period was 8.2 +/- 2.0 months. The average intraocular pressure peaks and fluctuation during the water drinking test were 20.0 +/- 2.9 mmHg and 40 +/- 10%, respectively, and 18.1 +/- 2.8 mmHg and 30 +/- 10% during follow up. Spearman's correlation coefficients were significant and strong between the intraocular pressure peaks and fluctuation detected during the water drinking test and during the follow-up period (P < 0.001, rho = 0.76 and 0.82,respectively). There was good agreement between the variables. CONCLUSION: The intraocular pressure peaks and fluctuation detected during the water drinking test showed significant correlation and agreement with the pressures observed during follow-up visits. Stress tests could be used to estimate long-term intraocular pressure variation.


Subject(s)
Glaucoma, Open-Angle/diagnosis , Intraocular Pressure , Stress, Physiological , Aged , Drinking , Female , Glaucoma, Open-Angle/drug therapy , Glaucoma, Open-Angle/physiopathology , Humans , Male , Middle Aged , Predictive Value of Tests , Prognosis , Prospective Studies , Prostaglandins/therapeutic use , Statistics as Topic , Time Factors
8.
Graefes Arch Clin Exp Ophthalmol ; 247(3): 385-9, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18987872

ABSTRACT

PURPOSE: To evaluate the correlation between intraocular pressure (IOP) rise, ocular pulse amplitude (OPA), and choroidal thickness (ChT) during the water drinking test (WDT). METHODS: Primary open-angle glaucoma (POAG) patients were submitted to the WDT followed by serial IOP measurements using dynamic contour tonometry (DCT), Goldman tonometry (GAT), and ChT measurements using ultrasonographic A and B-scan (USG). A control group not submitted to the test was also evaluated using DCT, GAT, and USG. Intraclass correlation coefficient (ICC) was calculated in the control group in order to assess the reproducibility of measurements. Spearman's coefficient (rho) was used to assess the correlation between the variables. RESULTS: Thirty eyes were included in the study. There was a significant IOP rise during the WDT using both GAT and DCT (p < 0.001). The OPA and ChT measurements also increased significantly (p < 0.001). Spearman's correlation between the OPA values and ChT measurements was significant and moderate (rho = 0.40, p = 0.005). The average increase of OPA and ChT measurements occurred 15 min before the IOP rise. CONCLUSIONS: There was a significant increase of OPA and ChT measurements followed by an IOP rise during the WDT. Increased choroidal volume due to hemodynamic forces may be enrolled in the mechanism of IOP elevation during this stress test.


Subject(s)
Choroid/physiopathology , Diagnostic Techniques, Ophthalmological , Drinking , Glaucoma, Open-Angle/physiopathology , Intraocular Pressure/physiology , Blood Pressure , Choroid/diagnostic imaging , Female , Humans , Male , Middle Aged , Ocular Hypertension/physiopathology , Tonometry, Ocular , Ultrasonography , Water
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