An alternative electroretinography protocol for children: a study of diagnostic agreement and accuracy relative to ISCEV standard electroretinograms

Abstract

Purpose: To assess the diagnostic accuracy and agreement between a paediatric electroretinography protocol used at Great Ormond Street Hospital (GOSH-ERG) and the ‘gold standard’ international protocol (ISCEV-ERG) in health and disease. Methods: Patient databases between 2010 and 2020 were screened to identify children with an ISCEV-ERG recorded within four years of a GOSH-ERG. Electroretinogram (ERG) component peak times and amplitudes were re-measured, and data were analysed in terms of absolute abnormality and proportional deviation from respective reference ranges. Abnormality was defined by the retinal system affected and by individual ERG a- and b-wave component analysis. Results: A total of 59 patients were included: 38 patients had retinal disease defined by an abnormal ISCEV-ERG and 21 had normal ISCEV-ERGs. When absolute abnormality was defined by combined retinal systems, the GOSH-ERG showed an excellent overall sensitivity of 95% (accuracy 86%). Individual retinal systems showed good–excellent sensitivity (67%–100%) and specificity (68%–97%). Electroretinogram (ERG) component sensitivities ranged between 60% and 97% and specificities between 79% and 97% dependent upon the protocol step. The proportional relationship appeared mostly linear between protocols. Electroretinogram (ERG) morphology was comparable for both protocols in a range of retinal diseases including those with pathognomonic ERGs. Conclusion: We demonstrate the high diagnostic accuracy of a paediatric ERG protocol (GOSH-ERG) relative to ISCEV standard ERGs. The close proportional deviation and similar waveform morphology indicate ERGs from each protocol are similarly affected in disease. This encourages the use of the GOSH-ERG protocol in the screening, diagnosis and monitoring of retinal disease in children who are unable to comply with the rigorous ISCEV-ERG protocol.