Share Email Print
cover

Proceedings Paper

Multifocal electroretinogram (MFERG) evaluation of laser-induced retinal injury with both indirect and direct registration of the MFERG stimulus pattern with the retinal landmarks
Author(s): Harry Zwick; Bruce E. Stuck; Andre Akers; Peter R. Edsall; Cheryl Dawn DiCarlo; David J. Lund
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Laser induced retinal damage may involve primary injury to the central retina and secondary damage, including intraretinal scar formation (IRSF) retinal traction (RT) and retinal nerve fiber layer injury (RNFL). We have evaluated these laser induced retinal pathologies with MFERG in non-human primates (NHPs) with a Veris (4.9) MFERG system 103 Hexagons, centered on the macula with non-scaled arrays and in one NHP with a 2-frame/M-step sequence to assess long term exposure effects within the RNFL. Chemical restraint was achieved using Ketamine stability HCL (10 mg/kg IM) and Propofol (0.5 mg-1.2/Kg/min via syringe pump). Peribulbar eye blocks were performed using 2% lidocain or a mixture of 2% Lidocain/Marcain (monitored ocular motility was less than 40 microns in retinal space). Primary and secondary damage effects were induced with either q-switched single pulse Neodymium (1064 nm, 1.0 mJ) or Argon CW (10 to 1000 msec, 10-150 mW). MFERG demonstrated capability to detect primary and secondary induced retinal damage in both 1st and 2nd order kernels. Primary and secondary damage in the central retina was often suppressed in amplitude and with longer latencies relative to the MFERG norm. Preliminary investigations in one NHP with Primary and secondary RNFL damage at 9 to 14 months showed recovery with non-scaled array one frame / M-step sequence but demonstrated significant abnormalities for a two frame/ M-step sequence. Utilization of advanced Veris recording parameters involving spatial and temporal manipulation of the stimulus parameters can improve detection of functional deficits induced by focal laser retinal injury.

Paper Details

Date Published: 18 April 2005
PDF: 7 pages
Proc. SPIE 5688, Ophthalmic Technologies XV, (18 April 2005); doi: 10.1117/12.598198
Show Author Affiliations
Harry Zwick, U.S. Army Medical Research Detachment (United States)
Bruce E. Stuck, U.S. Army Medical Research Detachment (United States)
Andre Akers, U.S. Army Medical Research Detachment (United States)
Peter R. Edsall, Northrop Grumman/Information Technology (United States)
Cheryl Dawn DiCarlo, U.S. Army Medical Research Detachment (United States)
David J. Lund, U.S. Army Medical Research Detachment (United States)


Published in SPIE Proceedings Vol. 5688:
Ophthalmic Technologies XV
Fabrice Manns; Per G. Söderberg; Arthur Ho; Bruce E. Stuck; Michael Belkin, Editor(s)

© SPIE. Terms of Use
Back to Top