Key Papers on Optic Disc Evaluation in Glaucoma (original) (raw)
Related papers
Ranking of optic disc variables for detection of glaucoma damage
Investigative Ophthalmology & Visual Science
PURPOSE. To describe optic disc variables assessed by evaluation of clinical optic disc photographs and to compare sensitivity and specificity of these optic disc parameters in identifying patients with ocular hypertension who have nerve fiber layer defects and normal visual fields and patients with visual field defects. METHODS. The study included 500 normal subjects, 132 patients with ocular hypertension with retinal nerve fiber layer defects and normal visual fields (preperimetric glaucoma), and 840 patients with glaucomatous visual field defects. Color stereo optic disc photographs were morphometrically evaluated. RESULTS. Highest diagnostic power for the separation between the normal group and the preperimetric glaucoma group had the vertical cup-to-disc diameter ratio corrected for its dependence on the optic disc size, total neuroretinal rim area, rim-to-disc area ratio corrected for disc size, and cup-to-disc area ratio corrected for disc size. Diagnostic power was lower for rim area in the temporal inferior and temporal superior disc sector, cup area corrected for disc size, and horizontal cup-to-disc diameter ratio corrected for disc size. Less useful for the differentiation between the normal subjects and the preperimetric glaucoma group were size of zones alpha and beta of parapapillary chorioretinal atrophy, and ratios of neuroretinal rim width and rim area comparing various optic disc sectors with each other. CONCLUSIONS. In subjects with ocular hypertension with retinal nerve fiber layer defects and normal conventional achromatic visual fields, the vertical cup-to-disc diameter ratio corrected for optic disc size, total neuroretinal rim area, rim-to-disc area ratio, and cup-to-disc area ratio corrected for disc size are the most valuable optic disc variables for early detection of glaucomatous optic nerve damage. Correction for optic disc size is necessary for optic disc variables directly or indirectly derived from the optic cup. Parapapillary atrophy is less important in the early detection of glaucoma.
A comparative study of two methods of optic disc evaluation in patients of glaucoma
Oman Journal of Ophthalmology, 2013
Introduction: Glaucoma is a progressive disorder and requires serial evaluation in order to monitor disease progression and optimize therapy. Objective: The objective of this study was to determine the correlation between each of cup/disc (C/D) ratio and the disc damage likelihood scale (DDLS) with retinal nerve fiber layer (RNFL) and global indices in Humphrey field analyzer II (HFA II). Design: Cross-sectional study. Materials and Methods: A total of 50 patients diagnosed with primary open angle glaucoma were examined to grade DDLS score and C/D ratio. The average (avg) RNFL was obtained using the Fast RNFL protocol on optical coherence tomography (OCT) (4.0.2 Carl Zeiss). HFA II Swedish Interactive Threshold Algorithm Standard 24-2 visual fields were obtained within 1 month of clinical examination. The correlation of C/D ratio with avg RNFL thickness, Mean deviation and Pattern standard deviation was calculated by Pearson correlation coefficient (r). Similar coefficients were obtained for DDLS. Results: The P value for the difference in the r between C/D ratio with RNFL (−0.628) and DDLS with RNFL (−0.8369) was significant (P < 0.01) when correlation of C/D, DDLS with RNFL was considered. Conclusion: The DDLS shows stronger correlation with structural changes in OCT than C/D ratio. The disc diameter and rim width increases the value of clinical optic disc examination.
2007
To compare the relationships between optic nerve structural measures and visual function, as well as the diagnostic sensitivity for glaucoma detection between the retinal nerve fiber layer (RNFL) and neuroretinal rim measurements. METHODS. A total of 101 normal and 156 glaucomatous eyes of 257 enrolled subjects were examined. RNFL thickness was measured by optical coherence tomography, and the neuroretinal rim (rim area, rim/disc area, and rim volume) was measured with a confocal scanning laser ophthalmoscope. The relationship between the structural measures and visual field sensitivity was evaluated with linear and non-linear-regression (quadratic and logarithmic) models. The coefficient of determination (R 2 ) was calculated, and the regression models were compared with Alkaike's information criteria and the F test. The diagnostic sensitivity for glaucoma detection in each structural measure was determined by the area under the receiver operating characteristic curve (AUC). RESULTS. The relationship of the RNFL, rim area, rim/disc area, and rim volume with visual function was best described with nonlinear regression models (quadratic regression for the RNFL [R 2 ϭ 0.383]), rim area [R 2 ϭ 0.303]), and rim/disc area [R 2 ϭ 0.265]; and logarithmic regression for rim volume [R 2 ϭ 0.175]). The change of visual sensitivity at each level of structural damage was highest for the RNFL. The AUC for the RNFL also was higher than the neuroretinal rim measures. In this study population, at 90% specificity, the diagnostic sensitivities for detecting glaucomatous damage was 82.7%, 67.3%, 67.3%, and 52.6% for the RNFL, rim area, rim/disc area, and rim volume, respectively. (These values would apply only to a group with inclusion criteria and disease severity similar to those of the present cohort.) CONCLUSIONS. The RNFL showed a stronger structure-function association and a higher diagnostic sensitivity for glaucoma detection than did the neuroretinal rim. (Invest Ophthalmol Vis Sci.
Five rules to evaluate the optic disc and retinal nerve fiber layer for glaucoma
Optometry - Journal of the American Optometric Association, 2005
A systematic approach for the examination of the optic disc and retinal nerve fiber layer is described that will aid in the detection of glaucoma. This approach encompasses 5 rules: evaluation of optic disc size, neuroretinal rim size and shape, retinal nerve fiber layer, presence of parapapillary atrophy, and presence of retinal or optic disc hemorrhages. A systematic process enhances the ability to detect glaucomatous damage as well as the detection of progression, and facilitates appropriate management.
Optometry and Vision Science, 2007
Purpose. To analyze the priority of morphological and functional defects in glaucoma. Methods. Nine-hundred seventy-three eyes of 973 subjects were examined with Heidelberg retinal tomograph (HRT II) and Octopus 311 perimeter (TOP strategy). These included 72 controls (C), 659 early and suspect open angle glaucoma (ESG) with perimetric mean defect (MD) lower than 6 dB, and 242 confirmed moderate and advanced glaucomas (AG) with perimetric MD Ն6 dB. Results. I. (Control group): Age was significantly correlated with mean sensitivity (MS) (r ϭ 0.50, p Ͻ 0.00001) and nasal cup shape measure (r ϭ 0.33, p ϭ 0.005). II. (C and ESG groups): For 95.8% specificity, the best sensitivity was obtained with square root of loss variance (sLV) (ROC area ϭ 69.7%, sensitivity ϭ 33.7%) and maximum contour elevation (ROC area ϭ 69.6%, sensitivity ϭ 29.0%). Maximum contour elevation and sLV coincided in diagnosis in 12.4% of cases. An equation using 64 HRT II indices predicted MS with a standard error of estimate (SEE) of 1.87 dB (r ϭ 0.67, p Ͻ 0.00001) and MD (SEE ϭ 1.88 dB, r ϭ 0.47, p Ͻ 0.00001). III. (All cases): RB discriminant function value was the best HRT II index to estimate MS values (SEE ϭ 5.4 dB, r ϭ 0.52, p Ͻ 0.0001), MD (SEE ϭ 5.2 dB, r ϭ 0.50, p Ͻ 0.0001), sLV (SEE ϭ 1.9 dB, r ϭ 0.41, p Ͻ 0.0001) and Number of Pathological Points (NPP; SEE ϭ 21.3 dB, r ϭ 0.49, p Ͻ 0.0001). Sector correlation of the optic nerve and visual field was high (maximum r ϭ 0.66) in cases with superior visual field defects and low in the rest of cases. More than 95% of cases with established glaucoma had abnormal sLV, but Ͻ60% had abnormal optic disc indices. Discussion. Perimetry reveals age-related defects slightly more than HRT II. HRT II indices correlated better with MS than with MD, probably because none of them was age corrected. Good correlation between anatomical and functional data in C and ESG, and sensitivity results indicated small differences in early development between both methods. Perimetry identifies defects more clearly than structural measures in established glaucoma.
Optic Disk Appearances in Primary Open-Angle Glaucoma
Survey of Ophthalmology, 1999
Primary open-angle glaucoma almost certainly develops in a multifactorial manner, with interplay between numerous risk factors affecting the disease. These risk factors, in addition to intraocular pressure, include a number of cardiovascular factors. Some of these factors may determine the appearance of the damaged glaucomatous optic nerve head. Patients with four specific optic disk appearances have been investigated, and differences have been identified in their demographic characteristics, prevalence of certain risk factors, the pattern of visual field damage, and circulatory abnormalities in their retrobulbar vessels. The findings provide evidence of the existence of subgroups of primary open-angle glaucoma with correlations between risk factor and type of optic disk. A reliable method by which the different disk appearances could be distinguished in an objective manner would be clinically valuable, and the scanning laser ophthalmoscope has shown potential promise to achieve this. The results of studies relating to various glaucomatous optic disk appearances are presented and discussed.
Ophthalmology, 2006
To evaluate the results of scanning laser tomography and scanning laser polarimetry (SLP) and the correlations with visual field damage (VFD) in eyes with nonarteritic ischemic optic neuropathy (n-AION) compared with eyes with open-angle glaucoma (OAG). Cross-sectional study. Thirty-three eyes of 33 patients with n-AION and 33 eyes with OAG whose age and VFD evaluated with the Humphrey field analyzer were matched to those of the n-AION eyes. The parameters of optic disc topography obtained with the Heidelberg Retina Tomograph II (HRT II) and retinal nerve fiber layer (RNFL) thickness with GDx with variable corneal compensation and the correlation to VFD. The cup area, cup-to-disc area ratio, and mean cup depth were significantly smaller, and the cup shape measure more negative, in the n-AION eyes than in the OAG eyes (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001), whereas rim area was significantly greater (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Multivariate analyses showed that none of disc area, rim area, and mean cup depth in the n-AION eyes and only rim area (P = 0.029) in the OAG eyes was significantly associated with mean deviation (MD). Ellipse average of RNFL thickness significantly correlated with MD in the n-AION eyes (P = 0.045) and in the OAG eyes (P = 0.022). Disc topography of eyes with n-AION was quantitatively characterized by small and shallow cupping and a relatively large rim area compared to eyes with OAG matched for age and VFD. In eyes with n-AION, significant correlation with VFD was found only for the RNFL thickness evaluated with SLP but not for the HRT II parameters.