title: Nonlinear component of the electroretinogram recorded from the posterior pole of normal and highly myopic human eyes.
abstract: To extract the nonlinear component of the electroretinogram (ERG) from the posterior pole (pp) of the human ocular fundus and to evaluate the possibility of its clinical application, three types of stimulus modes - double-flash, single-flash, and delayed single-flash stimuli - were produced using a conventional electrophysiological system. A large hexagonal element was presented on a CRT monitor, and ppERGs were recorded from 14 normal eyes and 16 eyes of eight highly myopic patients. The nonlinear component of the ppERG was obtained by subtracting the single-flash ERG and delayed single-flash ERG responses from the double flash ERG response. Three peaks were commonly observed in the nonlinear component of ppERG, all of which were significantly depressed in patients with high myopia. ppERGs that can be obtained using a simple algorithm might be useful in clinical applications.
authors.affiliation: Department of Ophthalmology, National Defense Medical College, Tokorozawa, Saitama, Japan. masaru33@me.ndmc.ac.jp
authors.forename: Masaru
authors.initials: M
authors.lastname: Yoshii
authors.forename: Kenji
authors.initials: K
authors.lastname: Yanashima
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Nagasaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Wada
authors.forename: Toshio
authors.initials: T
authors.lastname: Enoki
authors.forename: Shigekuni
authors.initials: S
authors.lastname: Okisaka
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004596:Electroretinography / Q000379:methods*; D005654:Fundus Oculi; D006801:Humans; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology*; D017711:Nonlinear Dynamics; D010775:Photic Stimulation; D011930:Reaction Time; D014792:Visual Acuity / Q000502:physiology