Contributing Factors for Progression of Visual Field Loss in Normal-tension Glaucoma Patients With Medical Treatment

Sung

Invest. Ophthalmol. Vis. Sci.

et al. 2015

PURPOSE.To evaluate the effect of optic disc tilt on the progression of glaucoma in myopic glaucomatous eyes.METHODS. The disc tilt ratio was estimated on disc photographs. Glaucomatous progression was determined either by stereoscopic optic disc/retinal nerve fiber layer photographs or serial visual field data. All participants were categorized into two groups according to tilt ratio (nontilted [<1.3] or tilted [ ‡1.3]). Kaplan-Meier life-table analysis was used to compare the survival experiences (time to confirmed glaucomatous progression) between groups. The hazard ratios (HRs) for the associations between potential risk factors and progression were determined by using Cox proportional hazards modeling. RESULTS.A total of 85 eyes in 85 myopic glaucoma patients (axial length > 24 mm; mean follow-up, 4.1 years) were included. Among them, 42 eyes (49.4%) demonstrated progression and 43 eyes (50.6%) were stable on follow-up. The mean disc tilt ratio was significantly smaller, and the prevalence of disc hemorrhage higher, in the progression than the stable group (P ¼ 0.032, P ¼ < 0.001, respectively). The cumulative probability of progression was 24.7% in the tilted group and 68.7% in the nontilted group (P ¼ 0.005). Disc hemorrhage (HR ¼ 3.317; P ¼ 0.001) and the tilt ratio (HR ¼ 0.110; P ¼ 0.046) were predictive of progression. CONCLUSIONS.Myopic eyes with tilted disc demonstrated a smaller probability of glaucomatous progression. Optic disc tilt may be protective against glaucoma progression, or tilted myopic glaucomatous eyes may have less progressive characteristic by nature.

mentioning

confidence: 99%

Implications of Optic Disc Tilt in the Progression of Primary Open-Angle Glaucoma

Sung

Invest. Ophthalmol. Vis. Sci.

et al. 2015

“…Many investigators have reported that myopia is a risk factor in NTG, 37 but the effect of myopia on the progression of glaucoma has yet to be elucidated. [38][39][40] In the current study, cluster 2 which represented mild myopia, displayed the worst VF deterioration, so we also cannot speculate on the relationship between VF progression and myopia. However, Lee et al 41 also reported that the incidence of VF progression was higher in eyes with mild myopia (> À 3 D) than in those with moderate myopia (> À6 D to < À3 D) in a group of treated POAG patients.…”

Section: Discussionmentioning

confidence: 68%

A Hierarchical Cluster Analysis of Normal-Tension Glaucoma Using Spectral-Domain Optical Coherence Tomography Parameters

Bae

et al. 2015

Journal of Glaucoma

Purpose: Normal-tension glaucoma (NTG) is a heterogenous disease, and there is still controversy about subclassifications of this disorder. On the basis of spectral-domain optical coherence tomography (SD-OCT), we subdivided NTG with hierarchical cluster analysis using optic nerve head (ONH) parameters and retinal nerve fiber layer (RNFL) thicknesses.Patients and Methods: A total of 200 eyes of 200 NTG patients between March 2011 and June 2012 underwent SD-OCT scans to measure ONH parameters and RNFL thicknesses. We classified NTG into homogenous subgroups based on these variables using a hierarchical cluster analysis, and compared clusters to evaluate diverse NTG characteristics.Results: Three clusters were found after hierarchical cluster analysis. Cluster 1 (62 eyes) had the thickest RNFL and widest rim area, and showed early glaucoma features. Cluster 2 (60 eyes) was characterized by the largest cup/disc ratio and cup volume, and showed advanced glaucomatous damage. Cluster 3 (78 eyes) had small disc areas in SD-OCT and were comprised of patients with significantly younger age, longer axial length, and greater myopia than the other 2 groups.Conclusions: A hierarchical cluster analysis of SD-OCT scans divided NTG patients into 3 groups based upon ONH parameters and RNFL thicknesses. It is anticipated that the small disc area group comprised of younger and more myopic patients may show unique features unlike the other 2 groups.Key Words: normal-tension glaucoma, hierarchical cluster analysis, spectral domain optical coherence tomography (J Glaucoma 2015;24:328-333) N ormal-tension glaucoma (NTG) is an optic neuropathy characterized by glaucomatous optic disc excavation and corresponding retinal nerve fiber layer (RNFL) change with intraocular pressure (IOP) in the statistically normal range. NTG is a common form of open-angle glaucoma throughout the world, but there are still many unanswered questions regarding the heterogenous feature of NTG.First, NTG is considered to have various pathophysiologies. IOP has been well known as the predominant risk factor in NTG, despite controversy, 1,2 and despite IOP being statistically within the normal range. High prevalence of disc hemorrhage in NTG suggested that the pathophysiology of NTG may be related to a vascular component. [3][4][5][6] Association between nocturnal hypotension and NTG suggested the importance of ocular blood perfusion, 7-9 and the vasospastic mechanism was thought to play an important role in both migraine and NTG. [10][11][12] Many previous studies also showed that several autoimmune dysfunctions may be possible etiologies of NTG. [13][14][15][16][17] In addition, the similarities between NTG and hereditary optic neuropathy such as Leber hereditary optic neuropathy and dominant optic atrophy have been reported in previous studies. 18,19 Second, the rate of progression also seems to be highly variable in NTG. In the Collaborative Normal Tension Glaucoma Study, 20 about half of NTG patients without treatment showed recognizable progression, but a...

“…22,[27][28][29][30] Some studies even reported protective effect of myopia against glaucoma progression. 31 Here, we aimed to test the hypothesis that thinner ONH may be a risk factor for glaucoma progression.…”

Section: Discussionmentioning

confidence: 99%

Lamina Cribrosa-Related Parameters Assessed by Optical Coherence Tomography for Prediction of Future Glaucoma Progression

Chung

Sung

et al. 2015

Current Eye Research