Purchase this article with an account.
M. Osako, K. Yamada, T. Agawa, M. Miura, K. Tachibana, M. Usui; Comparison of the results of scanning laser polarimetry with variable corneal compensator in POAG and NTG . Invest. Ophthalmol. Vis. Sci. 2004;45(13):3355.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: We investigated the retinal nerve fiber layer (RNFL) thickness and detectability of abnormalities in primary open–angle glaucoma (POAG) and normal–tension glaucoma (NTG) using scanning laser polarimetry with variable corneal compensator (GDx VCC). Methods: Fifty–five eye of 55 glaucoma patients and 25 eyes of 25 normal subjects were studied. Of the glaucoma cases, 26 eyes had POAG and 29 eyes had NTG. The mean deviation (MD) of Program 24–2 of the Humphrey Field Analyzer (HFA) averaged –7.3±7.7dB and –6.9±7.2dB, and corrected pattern standard deviation (CPSD) averaged 7.9±4.6dB and 7.6±4.4dB, in POAG and NTG groups, respectively. There were no significant differences in MD and CPSD between POAG and NTG groups (p=.86, p=.81). GDx parameters of TSNIT Average (TA), Superior Average (SA), Inferior Average (IA), TSNIT Standard Deviation (TSD), Nerve Fiber Indicator (NFI) were compared between the two groups using unpaired t–test. Defining a parameter below the 95% confidence interval or NFI greater than 50 as abnormal, we also compared the detectability for the two groups by each parameter using Mann–Whitney U–test. Results: When a case with any parameter outside normal limit (p<.05) was defined as abnormal, GDx VCC showed 87.2% sensitivity and 92.0% specificity (chi–square test, p<.001). Mean TA, SA, IA, and TSD were significantly greater in NTG than in POAG, whereas mean NFI was significantly smaller (p<.01). In early glaucoma cases with mean deviation (MD) greater than –5.0 dB (NTG: 17 eyes, POAG: 15 eyes, no significant difference in MD and CPSD between the two groups), TSD was significant larger in NTG than in POAG (p<.05), whereas no significant difference was found in the other parameters. Detectability of glaucoma by all parameters were significantly higher in POAG than in NTG (p<.01). In early glaucoma cases, TSD and NFI were significantly better in detecting POAG than NTG (P<.05). Conclusions:RNFL thickness is significantly smaller in POAG than in NTG, and GDX VCC detects POAG better than NTG.
This PDF is available to Subscribers Only