THE VALUE OF TWO-FIELD PATTERN ELECTRORETINOGRAM IN ROUTINE CLINICAL ELECTROPHYSIOLOGIC PRACTICE

Abstract

Purpose: 

To investigate the clinical use of the large-field pattern electroretinogram (PERG) as an adjunct test to the International-standard PERG in an unselected sequential cohort of patients referred for routine electrophysiologic assessment.

Methods: 

Pattern electroretinograms to both 15° × 11° (International Society for Clinical Electrophysiology of Vision Standard) and 30° × 22° (large field) checkerboard field sizes were recorded in 277 consecutive electrophysiology patients, aged 10–79 years. Most patients had additional tests including full-field electroretinogram, electrooculogram, multifocal electroretinograms, or cortical visual evoked potential. Patient data were compared with data from 27 control subjects.

Results: 

Satisfactory 2-field PERG data were obtained in 91% (N = 253) of patients; data from 24 patients (9%) were excluded because of poor compliance (n = 17) or nystagmus (n = 7). Standard PERGs were consistent with macular dysfunction in 44% of cases; large-field PERG revealed macular dysfunction in an additional 8% of eyes and helped to distinguish between localized central, predominantly paracentral, and widespread macular dysfunction. The results were consistent with multifocal electroretinogram and/or imaging studies on the same patients. In some patients with optic nerve disease, the large-field PERG provided clearer evidence of normal macular function than the standard PERG.

Conclusion: 

Routine use of the large-field PERG is a valuable complement to standard-field PERG testing in the evaluation and management of patients with different forms of macular or generalized retinal dysfunction and can be useful in patients with optic nerve disease.

In Brief

To investigate the clinical use of large-field (30° × 22°) pattern electroretinogram as an adjunct test to International-standard pattern electroretinogram (15° × 11°) in 277 patients. Routine use of large-field pattern electroretinogram is complementary to standard-field pattern electroretinogram in evaluation and management of patients with different forms of macular or generalized retinal dysfunction.