Hyoung Won Bae1, Yongwoo Ji, Hye Sun Lee, Naeun Lee, Samin Hong, Gong Je Seong, Kyung Rim Sung, Chan Yun Kim. 1. Departments of *Ophthalmology, Severance Hospital, Institute of Vision Research †Research Affairs, Biostatistics Collaboration Unit, Yonsei University College of Medicine ‡Departments of Ophthalmology, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea.
Abstract
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.
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.
Authors: Janelle Tong; Jack Phu; Sieu K Khuu; Nayuta Yoshioka; Agnes Y Choi; Lisa Nivison-Smith; Robert E Marc; Bryan W Jones; Rebecca L Pfeiffer; Michael Kalloniatis; Barbara Zangerl Journal: Am J Ophthalmol Date: 2019-05-10 Impact factor: 5.258
Authors: Jack Phu; Sieu K Khuu; Lisa Nivison-Smith; Barbara Zangerl; Agnes Yiu Jeung Choi; Bryan W Jones; Rebecca L Pfeiffer; Robert E Marc; Michael Kalloniatis Journal: Invest Ophthalmol Vis Sci Date: 2017-09-01 Impact factor: 4.799