Purchase this article with an account.
H. Saito, A. Tomidokoro, G. Tomita, M. Aihara, M. Araie; Retinal Nerve Fiber Thickness Measurement Using GDx With Enhanced Corneal Compensator . Invest. Ophthalmol. Vis. Sci. 2005;46(13):2515.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: GDx with Enhanced Corneal Compensator (GDx ECC) is a new program designed to make more accurate measurements of the retinal nerve fiber layer thickness (RNFLT) compared to the former program, GDx with Variable Corneal Compensator (GDx VCC). With the ECC program, following the VCC procedure, the retardation of the polarized laser beam is further corrected by enhancing the reflected laser beam according to RNFLT in order to diminish noise factors often seen in areas of thin nerve fiber layer. In this cross sectional study, GDx ECC was compared to GDx VCC as to the measurements of RNFLT and its correlation with the degree of visual field damage. Methods: The RNFLT of 50 open angle glaucoma (OAG) eyes was measured with GDx ECC and VCC simultaneously, and its correlation with the mean deviation (MD) of the Humphrey Central 30–2 SITA standard program was determined. Results: In 50 OAG eyes, there was no significant difference between the RNFLT measured with GDx ECC and that with VCC, showing good correlation with each other (R=0.92, P<0.0001). Both the RNFLT measured with ECC and that with VCC significantly correlated with MD (ECC: R=0.60, P<0.0001, VCC: R=0.51, P=0.002). In 20 eyes with myopia (<–3 diopters) out of the 50 OAG eyes, significant correlation between RNFLT and MD was seen only in the ECC measurement (ECC: R=0.57, P=0.0081, VCC: R=0.39, P=0.090), while in the other 30 eyes there was significant correlation between RNFLT and MD in both the ECC and VCC measurements (ECC: R=0.6196, P=0.0006, VCC: R=0.5073, P=0.0069). Conclusions: There were no significant differences in the measurements of GDx ECC and VCC in general. However, when limited to myopic eyes in which the retina should be relatively thin, better correlation with degree of visual field damage was seen in measurements with ECC than in those with VCC. GDx ECC should provide more accurate measurements of RNFLT in eyes with thinner retina, such as myopic eyes or advanced glaucoma eyes.
This PDF is available to Subscribers Only