Correlation between peripapillary atrophy and optic nerve damage in normal-tension glaucoma.
ABSTRACT To investigate the correlation between peripapillary atrophy and visual field defects as well as optic nerve head configurations in patients with normal-tension glaucoma (NTG).
Topographic measurements for peripapillary atrophy and optic nerve head using confocal scanning laser tomography and automated static threshold perimetry were performed on 102 eyes of 51 patients with NTG. Peripapillary atrophy was divided into (1) a central zone (zone Beta) with visible, large choroidal vessels and sclera, and (2) a peripheral zone (zone Alpha) with irregular hyper- and hypopigmentation. The area, angular extent around the disc, and radial extent of each zone were measured.
The area and extent of zone Beta increased significantly with increasing visual field defects expressed in terms of mean deviation, corrected pattern standard deviation, central visual field defects within 5 degrees of fixation, and superior hemifield defects (r = 0.3770-0.5291, P < 0.01). The angular extent of zone Beta represented localized field defects better (r = 0.5217, P < 0.001) than diffuse field defects (r = -0.3770, P < 0.01). Zone Beta significantly correlated with optic nerve head topography. Intraindividual right-left-side differences of corrected pattern standard deviation showed the highest correlation with the side differences of zone Beta area (r = 0.6305, P < 0.001). The location of visual field defects correlated significantly with the location of peripapillary atrophy (chi-square = 9.0484, P = 0.011). Zone Alpha was not significantly correlated with visual field defects or optic nerve head configurations (P > 0.05).
Peripapillary atrophy is significantly associated with functional and structural optic nerve damage in NTG.
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ABSTRACT: Purpose: To evaluate the reproducibility of measurements of area of β-zone parapapillary atrophy (β-PPA) using blue laser fundus autofluorescence (FAF) and confocal scanning laser ophthalmoscopy reflectance (CSLO) measurements and to assess agreement between the two imaging modalities. Methods: Sixty-five eyes of 45 patients (mean age, 68.2 ± 11.3 years) with established or suspected glaucoma from the Diagnostic Innovations in Glaucoma Study (DIGS) were prospectively included. FAF scans were obtained with the Spectralis HRA+OCT and CSLO reflectance images with the HRTII (both from Heidelberg Engineering, Heidelberg, Germany). Two masked graders independently measured β-PPA area on 3 consecutive scans using the semi-automated BluePeak RegionFinder software (BPRF) and on CSLO reflectance images using the optic disc contour line. Reproducibility of β-PPA area measurements was assessed using intraclass correlation coefficients (ICC). Results: Intragrader reproducibility was 0.997 (95% CI, 0.996-0.998) and 0.995 (95% CI, 0.992-0.996) for grader 1 and 2, respectively, using FAF-BPRF, and by CSLO, it was 0.991 (95% CI, 0.986-0.994) and 0.988 (95% CI, 0.982-0.992). Intergrader agreement (ICC) was 0.53 (95% CI, 0.331-0.685) for FAF-BPRF and 0.404 (95% CI, 0.149-0.601) for CSLO (comparison between ICC, p = 0.368). Agreement (ICC) between the two devices was worse for grader 1 (0.356; 95% CI, 0.129-0.549) than grader 2 (0.856; 95% CI, 0.774-0.910) (p < 0.001). Conclusions: Despite excellent intragrader reproducibility for β-PPA measurements with FAF-BPRF and CSLO, intergrader reproducibility is low to moderate. Measurements of β-PPA area obtained with the two instruments are of moderate agreement and, therefore, are not interchangeable.Acta ophthalmologica 03/2013; · 2.44 Impact Factor
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ABSTRACT: OBJECTIVE: To investigate whether a topographic correlation exists between β-zone parapapillary atrophy (PPA) and retinal nerve fiber layer (RNFL) defect. The location and extent of the β-zone were examined. DESIGN: Retrospective, cross-sectional study. PARTICIPANTS: One hundred twenty-eight eyes from 128 consecutive patients with primary open-angle glaucoma (POAG) and a single localized RNFL defect were included. METHODS: Digital optic disc photographs of the enrolled eyes were reviewed and eyes with β-zone PPA were identified. The topographic parameters of β-zone PPA and RNFL defect were measured on optic disc photographs and digital red-free RNFL photographs. The association between these parameters was examined statistically. MAIN OUTCOME MEASURES: Angular location and angular extent of β-zone PPA and RNFL defect, angular location of point of maximum radial extent (PMRE) of β-zone PPA, and β-zone PPA-to-disc area ratio. RESULTS: Eighty-two (64.1%) of the 128 eyes with a single localized RNFL defect had β-zone PPA. Patients with β-zone PPA were younger (by 6.6 years) than those without β-zone PPA (P = 0.001). β-Zone PPA was located most commonly inferotemporally (65.9%). The RNFL defect was located in the same hemifield as the β-zone PPA in 76% of eyes and was located in the same hemifield as PMRE in 88% of eyes. The angular location of the RNFL defect showed a linear correlation with those of β-zone PPA (r = 0.390; P<0.001) and PMRE (r = 0.558; P<0.001). The angular extent of RNFL defect was not correlated significantly with that of β-zone PPA (P = 0.106), but it was associated weakly with β-zone PPA-to-disc area ratio (r = 0.197; P = 0.026). The angular extent of the RNFL defect also was correlated with the cup-to-disc ratio (r = 0.322; P<0.001) and the cup-to-disc area ratio (r = 0.337; P = 0.002). CONCLUSIONS: In POAG, a localized RNFL defect is correlated spatially with β-zone PPA. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.Ophthalmology 12/2012; · 5.56 Impact Factor
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ABSTRACT: Purpose: To investigate whether the amount of intraocular pressure (IOP) reduction with topical medications is associated with the progression of normal-tension glaucoma (NTG) and to identify risk factors for NTG progression. Methods: The medical records of 121 eyes of 121 NTG patients, who were treated with topical medications for more than 7 years, were reviewed. NTG progression was defined by either structural (optic disc or retinal nerve fibre layer) or functional (visual field) deterioration. Patients were divided into tertile groups according to the percentage IOP reduction from baseline, and the cumulative probability of NTG progression between upper and lower tertile group was compared using Kaplan-Meier survival analysis. Multivariate analysis with Cox's proportional hazard model was performed to identify the hazard ratio (HR) of clinical factors for NTG progression. Results: The average follow-up period was 12.2 years, and 56 of 121 eyes (46.3%) showed the NTG progression. Kaplan-Meier analysis revealed that upper tertile group (percentage IOP reduction >22.1%) showed a greater cumulative probability of non-progression than lower tertile group (percentage IOP reduction < 13.3%; p = 0.012). Multivariate Cox's proportional hazard model indicated that percentage reduction of IOP (HR = 0.964; p = 0.007) and the occurrence of disc haemorrhage (HR = 2.410; p = 0.008) were significantly associated with NTG progression. Conclusions: The amount of IOP reduction using topical medications was related to NTG progression, and lower percentage reduction in IOP was a consistent risk factor for progression.Acta ophthalmologica 02/2013; · 2.44 Impact Factor