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Abstract #12014 Published in IGR 7-1
Pattern electroretinogram abnormality and glaucoma
Ventura LM; Porciatti V; Ishida K; Feuer WJ; Parrish RK 2ndOphthalmology 2005; 112: 10-19
PURPOSE: To determine the existence of retinal ganglion cell dysfunction and associated risk factors in glaucoma suspects with increased optic disc cupping and normal visual field. DESIGN: Cross-sectional, observational study. PARTICIPANTS: Two hundred glaucoma suspect (GS) patients were identified based on optic disc abnormalities (vertical cup-to-disc ratios [C/D] > 0.5; vertical C/D asymmetry ≥ 0.2; disc hemorrhages; notching) in association with known glaucoma risk factors (positive family history, African American descent, increased intraocular pressure [IOP]), but normal visual fields. Forty-two patients had early manifest glaucoma (EMG). Sixteen normal black subjects were added to update previous pattern electroretinogram (PERG) normative data and to establish a normal control (NC) group with a racial breakdown comparable with that of the study groups. METHODS: Pattern electroretinograms were recorded simultaneously from both eyes using skin electrodes and automated analysis; visual fields were monitored with standard white-on-white automated perimetry (SAP) central 24-2 program; vertical C/D was evaluated by an independent reader from stereo disc photographs; and univariate and multivariate statistical analysis between PERG and other outcome measures was evaluated. MAIN OUTCOME MEASURES: Pattern electroretinogram amplitude (microV), phase (pi rad), and interocular asymmetry in amplitude and phase (%); and SAP mean deviation (MD; decibels), vertical C/D, age (years), IOP (mmHg), and race (black vs. nonblack). RESULTS: The PERG results were abnormal in at least 1 of the outcome measures in 52% of GS patients and 69% of EMG patients. The PERG amplitude was correlated weakly with both MD (P < 0.01) and vertical C/D (P = 0.05). The correlation between PERG amplitude and MD and C/D was stronger (P < 0.001) for interocular differences rather than absolute measures. Interocular PERG amplitude asymmetry increased with severity of disease (EMG > GS > NC; P < 0.01). The PERG amplitude decline with age was steeper in patients with a more negative MD (P < 0.01) and in patients with a more negative MD and a larger vertical C/D (P = 0.06). Black race (but not family history) was associated with lower PERG amplitude (P = 0.005) in GS and EMG patients, but not in normal controls (P = 0.44). CONCLUSIONS: The correlation between PERG abnormality and known risk factors for glaucoma indicates that PERG has a predictive potential for the development or progression of the disease, or both.
Dr. L.M. Ventura, Bascom Palmer Eye Institute, Miami, Florida 33136, USA
Classification:
6.7 Electro-ophthalmodiagnosis (Part of: 6 Clinical examination methods)
