Nerve fibre layer analysis with GDx with a variable corneal compensator in patients with multiple sclerosis

Purpose: To evaluate the ability of GDx with variable corneal compensator ( VCC) compared to visual- evoked potentials ( VEPs) and standard automated perimetry ( SAP) in the detection of early optic nerve damage in patients with multiple sclerosis ( MS). Methods: 46 eyes of 23 MS patients were included. Ten of them had a history of acute retrobulbar optic neuritis. A control group of 20 normal subjects was also included. All subjects underwent a complete ophthalmological examination and testing with SAP, GDx VCC and VEPs. Results: 19 eyes ( 41.3%) were abnormal with GDx VCC compared to 38 eyes ( 82.6%) with SAP and 31 ( 64.4%) with VEPs. In the optic neuritis group, 9 eyes ( 69.2%) had optic nerve pallor; SAP was abnormal in 8 of these eyes ( 61.5%) while VEPs and GDx VCC were abnormal in 6 eyes ( 46.1%). 2/ 20 eyes ( 10.0%) in the control group gave a false- positive abnormal result with SAP. GDx VCC and VEP were normal for all the eyes in the control group. Conclusions: GDx VCC is less able to detect early defects in MS patients compared to the currently used standard techniques of SAP and VEPs. Copyright (c) 2007 S. Karger AG, Basel.