A Diagnostic Calculator for Detecting Glaucoma on the Basis of Retinal Nerve Fiber Layer, Optic Disc, and Retinal Ganglion Cell Analysis by Optical Coherence Tomography (original) (raw)
Related papers
PURPOSE. We determined the glaucoma screening performance of regional optical coherence tomography (OCT) layer thickness measurements in the peripapillary and macular region, in a population-based setting. METHODS. Subjects (n ¼ 1224) in the Rotterdam Study underwent visual field testing (Humphrey Field Analyzer) and OCT of the macula and optic nerve head (Topcon 3-D OCT-1000). We determined the mean thicknesses of the retinal nerve fiber layer (RNFL), retinal ganglion cell layer (RGCL), and inner plexiform layer for regions-of-interest; thus, defining a series of OCT parameters, using the Iowa Reference Algorithms. Reference standard was the presence of glaucomatous visual field loss (GVFL); controls were subjects without GVFL, an intraocular pressure (IOP) of 21 mm Hg or less, and no positive family history for glaucoma. We calculated the area under the receiver operating characteristics curve (AUCs) and the sensitivity at 97.5% specificity for each parameter. RESULTS. After excluding 23 subjects with an IOP > 21 mm Hg and 73 subjects with a positive family history for glaucoma, there were 1087 controls and 41 glaucoma cases. Mean RGCL thickness in the inferior half of the macular region showed the highest AUC (0.85; 95% confidence interval [CI] 0.77-0.92) and sensitivity (53.7%; 95% CI, 38.7-68.0%). The mean thickness of the peripapillary RNFL had an AUC of 0.77 (95% CI, 0.69-0.85) and a sensitivity of 24.4% (95% CI, 13.7-39.5%). CONCLUSIONS. Macular RGCL loss is at least as common as peripapillary RNFL abnormalities in population-based glaucoma cases. Screening for glaucoma using OCT-derived regional thickness identifies approximately half of those cases of glaucoma as diagnosed by perimetry.
Investigative Opthalmology & Visual Science, 2007
PURPOSE. To evaluate the relationship between optic nerve head (ONH) and peripapillary retinal nerve fiber layer (RNFL) parameters by optical coherence tomography (OCT) and confocal scanning laser ophthalmoscopy (Heidelberg retinal tomography; HRT; Heidelberg Engineering, Heidelberg, Germany) in early and moderate glaucoma and to compare several OCT-based automated classifiers with those inbuilt in HRT for detection of glaucomatous damage. METHODS. This cross-sectional study included 60 eyes of 60 patients with glaucoma (30 early and 30 moderate visual field defects) and 60 eyes of 60 healthy subjects. All patients underwent Fast Optic Disc and Fast Peripapillary RNFL scans on the OCT and then HRT evaluation of the ONH during the same visit. Glaucoma variables obtained from OCT and HRT analyses were compared among the groups. Receiver operator characteristic (ROC) curves generated by performing linear discriminant analysis (LDA), artificial neural networks (ANNs), and classification and regression trees (CART) on OCT-based parameters were compared with the Moorfield regression analysis (MRA), R Bathija (RB), and FS Mickelberg (FSM) functions in the HRT, to classify eyes as either glaucomatous or normal. RESULTS. No statistically significant difference was found in the disc area measured by the OCT and HRT analyses within each study group (P Ͼ 0.05). The areas under ROC curves were 0.9822 (LDF), 0.9791 (CART), and 0.9383 (ANN) as compared with 0.859 (FSM), 0.842 (RB) and 0.767 (MRA). CONCLUSIONS. OCT-based automated classifiers performed better than HRT classifiers in distinguishing glaucomatous from healthy eyes. Such parameters should be integrated in the OCT to improve its diagnostic abilities.
Different Clinical Parameters to Diagnose Glaucoma Disease: A Review
International Journal of Computer Applications, 2015
Glaucoma is a severe human eye disease that causes permanent loss of vision. The main cause of glaucoma eye disease is the continuous loss of retinal nerve fiber layers due to the increase in the intra ocular pressure inside the eyes. The function of these retinal nerve fibers is the transformation of recognized object information in the form of signals to the brain, where these signals are recognized as object. Damages to these nerve fibers generate blind spots and these blind spots leads to permanent blindness. Therefore, Retinal Nerve Fiber Layer Thickness is the main parameter to diagnose glaucoma. Other parameters also leading to glaucoma are Intraocular Pressure, Vertical Cup to Disc Ratio, Neuro Retinal Rim Thickness, Central Cornea Thickness, Inferior Superior Nasal and Temporal Sector Ratio etc. Therefore, the identification of these parameters plays the major role in glaucoma assessment, since it allows timely treatment to prevent the vision loss caused by glaucoma. To estimate these parameters, clinical instruments such as Tonometry, Ophthalmoscopy, Heidelberg Retinal Tomography, Perimetry, Pachymetry, Optical Coherence Tomography, GDx etc are adopted. This paper presents the various parameters, as mentioned above, used to analyze and diagnose the Glaucoma disease and associated advantages, disadvantages and the different instruments used to analyze each clinical parameter.
Acta Informatica Medica, 2014
Goal: the purpose of the current study was to estimate the predictive values of optical coherence tomography parameters in early, developed perimetric and terminal glaucoma. Methods: 180 eyes of 120 consecutive patients were evaluated in this retrospective cross sectional pilot study. Copernicus Spectral -domain optical coherence tomography with resolution of 3 mm obtained throught the optic nerve head were included. All examined eyes were divided to four groups (healthy,early, developed perimetric glaucoma and terminal glaucoma). The values of the thicknes of the retinal nerve fibre layer, the size of the disk, the volume of the cup, the E/D parameter and the size of the RIM were compared in four study groups. Results:The sensitivity of RNFL was 90,0%, specificity 82,0 %, positive predictability 83,3 % and negative predictability was 89,1 %. The total accuracy was 86,0 % and area under curve (AUC) was 0,878 for RNFL indeks compering early to developed glaucoma. The sensitivity for CUP was 78%, the specificity was 80,8 %, the positive predictability 81,2% and the negative predictability was 77,5 %. The total accuracy was 79,3 % and area under curve (AUC) was 0,86 compering early to developed glaucoma. The sensitivity for E/D was 82,0%, the specificity was 82,9 % the positive predictability 83,7 % and the negative predictability was 81,3 %. The total accuracy was 82,5 % and area under curve (AUC) for E/D was 0,89 compering eearly to developed glaucoma.The sensitivity for RIM was 78,0%, the specificity was 76,6 %, the positive predictability was 84,7 and the negative predictability was 67,7 %. The total accuracy was 77,5 % and area under curve (AUC) for the RIM compering the developed to terminal glaucoma was 0,792. The sensitivity of RNFL was 88,0 %, the specificity was 66,7 %, the positive predictability was 81,5% and the negative predictability was 76,9%. The total accuracy was 80,0% and the area under curve (AUC) for RNFL compering developed to terminal glaucoma was 0,815. The incrreasing 0,1 unit RNFL decreases the risk of developing glaucoma from early to another developed stage of glaucoma for 6,95%. The increasing of E/D for only one unit increases the risk to develop another stage of glaucoma for 18,75 times. The increasing of RNFL for only one unit decreases the risk of performing developed glaucoma from initial stage for 7,8%. The increasing for only one unit of CUP increases the risk to develop terminal glaucoma for 8,47 times and increasing for 0,1 unit of the value of RIM decreases the risk developing terminal glaucoma for 9,27%. The increasing for 0,01 unit of the E/D index increases the risk for terminal glaucoma for 23,23 times. The increasing for one unit of RNFL decreasing the risk developing terminal glaucoma for 5,7%.
Acta Ophthalmologica, 2022
Purpose: Detection of early glaucoma remains limited with the conventional analysis of the retinal nerve fiber layer (RNFL). This study assessed whether compensating the RNFL thickness for multiple demographic and anatomic factors improves the detection of glaucoma. Design: Cross-sectional study. Participants: Three hundred eighty-seven patients with glaucoma and 2699 healthy participants. Methods: Two thousand six hundred ninety-nine healthy participants were enrolled to construct and test a multivariate compensation model, which then was applied in 387 healthy participants and 387 patients with glaucoma (early glaucoma, n ¼ 219; moderate glaucoma, n ¼ 97; and advanced glaucoma, n ¼ 71). Participants underwent Cirrus spectral-domain OCT (Carl Zeiss Meditec) imaging of the optic disc and macular cubes. Compensated RNFL thickness was generated based on ethnicity, age, refractive error, optic disc (ratio, orientation, and area), fovea (distance and angle), and retinal vessel density. The RNFL thickness measurements and their corresponding areas under the receiver operating characteristic curve (AUCs) were obtained. Main Outcome and Measures: Measured and compensated RNFL thickness measurements. Results: After applying the Asian-specific compensation model, the standard deviation of RNFL thickness reduced, where the effect was greatest for Chinese participants (16.9%), followed by Malay participants (13.9%), and Indian participants (12.1%). Multivariate normative comparison outperformed measured RNFL for discrimination of early glaucoma (AUC, 0.90 vs. 0.85; P < 0.001), moderate glaucoma (AUC, 0.94 vs. 0.91; P < 0.001), and advanced glaucoma (AUC, 0.98 vs. 0.96; P < 0.001). Conclusions: The multivariate normative database of RNFL showed better glaucoma discrimination capability than conventional age-matched comparisons, suggesting that accounting for demographic and anatomic variance in RNFL thickness may have usefulness in improving glaucoma detection.
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.
Journal of Ophthalmology and Advance Research, 2024
Purpose: To characterize the ability of ImageJ-derived measurements of Optical Coherence Tomography Angiography (OCTA) to diagnose healthy vs Primary Open-Angle Glaucoma (POAG) Eyes. Methods: This retrospective study analyzed 85 healthy and 81 POAG eyes. Initially, demographics, historical data, intraocular pressure, cup/disc ratio and retinal nerve fiber layer thickness were collected for all patients. Thereafter, quantitative vascular parameters including Vessel Density (VD), Vessel Length Density (VLD) and Fractal Dimension (FD) were obtained by analyzing OCTA scans using the open-source software ImageJ. Measurements were obtained from the Radial Peripapillary Capillary (RPC) layer of the optic nerve head and the superficial and deep capillary plexuses of the macula. Fifty healthy and fifty POAG eyes (training set) were randomly selected to train two diagnostic models: one based on OCTA parameters (model A) and the other based on clinical and structural data (model B). These models were tested on the remaining 35 healthy and 31 POAG eyes and receiver operating curves were constructed to compare their ability to identify POAG. Results: VD, VLD and FD as obtained by ImageJ were all significantly reduced in the POAG group (p < 0.0001). The RPC layer was the most effective at classifying glaucoma (AUC = 0.9184, CI: 0.85-0.98). Model A (AUC = 0.917, CI: 0.847-0.986) slightly outperformed model B (AUC = 0.863, CI: 0.776-0.949), albeit not to the level of statistical significance (p = 0.111) Conclusion: Our pilot study indicates that OCTA vascular parameters are similar in effectiveness to clinical exam and structural features at diagnosing glaucoma.
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.