Pattern electroretinography of larger stimulus field size and spectral-domain optical coherence tomography in patients with Stargardt disease
- 1Eye Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- 2Institute of Pathology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- Correspondence to Professor M Hawlina, Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, SI-1000 Ljubljana, Slovenia;
- Accepted 3 June 2009
- Published Online First 23 July 2009
Aims: To investigate the importance of a larger stimulus field for pattern electroretinography (PERG) in evaluating macular function in Stargardt disease, and to determine the relationship between PERG and spectral-domain optical coherence tomography (SD-OCT).
Methods: In this prospective cross-sectional study, PERG from standard (12°×16°) and larger (24°×32°) stimulus fields and SD-OCT were recorded in 18 patients with genetically confirmed Stargardt disease, and in 18 control subjects.
Results: A PERG P50 response to the larger stimulus field was detectable in 86% of eyes, with a mean P50 amplitude of 2.3 μV, compared with 22% and 1.0 μV for the standard stimulus field. The specificity and sensitivity of PERG to the standard stimulus field were greater than for the larger field. For both PERG P50 and N95, the differences in their amplitudes between the standard and larger stimulus fields correlated significantly with visual acuity and SD-OCT parameters.
Conclusion: The higher sensitivity and specificity of PERG to the standard stimulus field provide detection of early maculopathy in Stargardt disease, while PERG with the larger stimulus field allows for longer follow-up. The PERG amplitude for the larger stimulus field correlated with severity of transverse photoreceptor loss in SD-OCT. These methods are complementary for evaluation of progression of photoreceptor damage in patients with Stargardt disease.
Funding This study was supported by the Slovenian Research Agency, Grant No P3-0333.
Competing interests None.
Ethics approval Ethics approval was provided by the National Medical Ethics Committee of the Republic of Slovenia.
Patient consent Obtained.
Ethics approval: Ethics approval was obtained.
Provenance and peer review Not commissioned; externally peer reviewed.