Abnormal 8-Hz flicker electroretinograms in carriers of X-linked retinoschisis

• Published in: Documenta ophthalmologica Vol. 133; no. 1; pp. 61 - 70
• Main Authors: McAnany, J. Jason, Park, Jason C., Collison, Frederick T., Fishman, Gerald A., Stone, Edwin M.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2016; Springer Nature B.V
• Subjects: Adult; Aged; Case-Control Studies; Dark Adaptation - physiology; Electroretinography - methods; Female; Flicker Fusion - physiology; Humans; Male; Medicine; Medicine & Public Health; Middle Aged; Ophthalmology; Original Research Article; Photic Stimulation - methods; Retina; Retinal Cone Photoreceptor Cells - physiology; Retinal Rod Photoreceptor Cells - physiology; Retinoschisis - physiopathology; Vision, Ocular - physiology; Electroretinogram (ERG); Cone; Flicker; Rod; X-linked retinoschisis
• ISSN: 0012-4486; 1573-2622
• DOI: 10.1007/s10633-016-9551-0

Purpose To evaluate rod-isolated, cone-isolated, and combined rod and cone flicker electroretinograms (ERGs) as a possible means to identify electrophysiological abnormalities in carriers of X-linked retinoschisis (XLRS). Methods Full-field ERGs were recorded from six carriers of XLRS (aged 34–66 years) and eight normally sighted subjects (aged 27–59 years) under rod-isolated (ERG R ), cone-isolated (ERG C ), and combined rod and cone (ERG R+C ) conditions. ERGs were obtained using a four-primary LED-based ganzfeld photostimulator and standard recording techniques. The four primaries were modulated sinusoidally in phase to achieve combined rod and cone activation (ERG R+C ) or in different phases to achieve ERG R and ERG C by means of triple silent substitution. After 30 min of dark adaptation, 8- and 15-Hz ERG R , ERG C , and ERG R+C responses were obtained at a mean luminance level of 24 scot. cd/m 2 . Standard ISCEV ERGs were also obtained from each subject. Results The ISCEV and 15-Hz flicker ERGs were generally within the normal range for the carriers. The 8-Hz ERG R , ERG C , and ERG R+C amplitudes were also generally normal. In contrast, the carriers had ERG R , ERG C , and ERG R+C timing abnormalities, with phase advances beyond the range of normal for the ERG R (four carriers), ERG C (four carriers), and ERG R+C (three carriers). Only one carrier had normal 8-Hz responses under all conditions. Conclusions The 8-Hz ERG timing abnormalities in five of six carriers indicate that retinal function is not necessarily normal in carriers of XLRS. The 8-Hz flicker ERG may be useful for studying retinal function in these individuals.