A COMPARATIVE-STUDY OF INTRAOCULAR IRRIGATING SOLUTIONS - EFFECTS ON ELECTRORETINOGRAPHY READINGS DURING CLOSED VITRECTOMY IN HUMANS

The effects of intraocular irrigating solutions on electroretinography have been extensively studied in animal models, but effects on human electroretinography have not been reported. This study examined the ef fects of two commercially available irrigating solutions, S-MA(2) (Ope guard MA(R)) and DE-057 (BBS-Plus(R)) on 30-Hz flicker electroretinogr aphy during closed vitrectomy in humans. Eight eyes of 8 patients were examined. All patients underwent a simple vitrectomy without treatmen t of proliferative membrane. For 30-Hz nicker electroretinography reco rding, a contact lens with a built-in light-emitting diode was sterili zed and used as both a stimulus source and a recording electrode. Repl acing S-MA(2) with DE-057 decreased the electroretinography amplitude from 55.8 +/- 15.2 to 45.5 +/- 13.2 mu V (mean +/- SEM). Changing the irrigation solution from DE-057 back to S-MA(2) increased the amplitud e from 45.5 +/- 13.2 to 59.9 +/- 17.3 mu V. However, these changes wer e `not statistically significant. Replacing S-MA(2) with DE-057 signif icantly increased the peak time from 50.1 +/- 1.5 to 57.6 +/- 1.3 msec (p<0.001). This change was reversible; after changing from DE-057 bac k to S-MA(2), the peak time of flicker electroretinography significant ly decreased from 57.6 +/- 1.3 to 49.0 +/- 2.1 msec (p<0.01). Thus int raoperative 30-Hz electroretinography showed delayed peak time during irrigation with DE-057, as compared with S-MA(2). The lower potassium concentration and higher glucose concentration of S-MA(2), as compared with DE-057, may be the cause of such electroretinography changes.