Abstract
Purpose :
Many patients, especially children, are unable to tolerate electroretinogram (ERG) testing with contact lens electrodrodes (CLEs). Our retrospective study aimed to analyze the effectiveness of diagnosis with LKC SensorStrip adhesive skin electrodes as an alternative to CLEs in ERG testing.
Methods :
Photopic then scotopic ERGs were recorded from both eyes simultaneously in 29 patients with the Diagnosys Espion-3 electrodiagnostic system using the ColorDome ganzfeld stimulator. LKC SensorStrip electrodes were used instead of CLEs. The DA 0.01 flash was often omitted due to limited cooperation, and DA 10.0 responses were rarely obtained. Response waveforms were viewed with a 5-fold increase in vertical gain to approximate the waveform shapes familiar from recordings with CLEs.
Results :
Patients ranged in age from 2 to 29 years. Diagnoses included achromatopsia (n=5), amblyopia (n=3), cobalamin-C disease (n=1), primary motor nystagmus (n=4), congenital stationary night blindness (CSNB) (n=3), fundus albipunctatis (n=1), Leber congenital amaurosis (LCA) (n=3), Stargardt disease (n=1), Usher syndrome (n=2), cortical visual impairment (n=2), macular dystrophy (n=1), photophobia of unknown etiology with normal retinal function (n=1), and “rule-out” peripheral cone degeneration (n=2). ERGs were essentially extinguished in 3 patients (2 with Usher syndrome, 1 with LCA). “Normal” response amplitudes to the LA 3.0 flash ranged from 16.0 to 43.7 µV; “Normal” responses to 30-Hz photopic flicker ranged from 12.0 to 46.2µV; “Normal” responses to the DA 3.0 flash ranged from 31.5 to 68.0 µV. Implicit times were similar to those expected with CLEs. Typical ERG patterns diagnostic for achromatopsia, CSNB and the extinguished ERGs in Usher syndrome and LCA were readily recognizable.
Conclusions :
ERGs obtained with LKC SensorStrip adhesive electrodes proved useful in the diagnosis of a spectrum of retinal disorders, despite an inability to interpret response amplitudes quantitatively. This technique was useful mainly in children with ages ranging from 2 to 10 years, but also in adults who are unable to tolerate CLEs. Further studies to better determine the “amplitude conversion factor” and the comparative variability of ERG amplitudes between SensorStrip electrodes and conventional CLEs are warranted, and may further clarify the interpretation of SensorStrip ERGs.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.