Local ERG for clinical examination of eye diseases

Abstract

We used a suction electrode with a frosted front window to record a full-field (general) ERG, and a suction electrode with a short-focus lens and a red-green light diode to record a local ERG. As the suction electrode moved with the eye, the stimulus struck the macula in all positions of gaze. Our data showed that only mildly intense stimuli with an angular size of 10 to 15 degrees induced a retinal response, with a macular contribution of 70%. Patients with various dystrophic changes of the retina, such as Stargardt's dystrophy, vitelliform dystrophy of the Best type, X-linked juvenile retinoschisis, and age-related macular dystrophy of different stages, were examined. In patients with retinitis pigmentosa, the cones were involved in the pathologic process to varying degrees; the behavior of the local ERGs helped determine the final visual acuity. We also observed a reduction in the local ERG in patients with Stargardt's dystrophy that disappeared as the disease progressed. In age-related macular dystrophy, a disturbance of the electrogenesis mainly occurred in the central retina in advanced stages of the disease.

Electrophysiological abnormalities in age-related macular degeneration

“…On the other hand in geographic atrophy the bipolar input from cones seemed to be reduced because in this group the amplitudes are reduced but the implicit times are normal. In a large series of 1270 patients Shamshinova identified 12 eyes with drusen [27]. In these eyes the ERG was normal.…”

Two novel mutations in the bestrophin-1 gene and associated clinical observations in patients with best vitelliform macular dystrophy

“…It has been hypothesized that mutations in BEST1 may result in channel dysfunction which leads to abnormal fluid and ion transport through the RPE, resulting in defects during ocular growth and later-onset retinal dystrophy (18,19). …”

Prospects of Visual Evoked Potentials Latency Application in Psychophysiology

“…В корковый отдел анализатора, расположенный в области шпорной борозды затылочной доли мозга, поступают импульсы как от фоторецепторов сетчатки, так и от проприорецепторов наружных мышц глазного яблока, а также мышц радужной оболочки и цилиарного тела. Кроме того, установлены тесные ассоциативные свя-зи зрительного анализатора с другими сенсорными системами [15].…”