Comparison between a new type of dipolar corneal contact lens electrode and the Jet corneal contact lens electrode for multi-focal electroretinograms

Abstract

Objective To compare the application and degree of comfort of a new type of dipolar corneal contact lens electrode and the Jet corneal contact lens electrode; to evaluate the potential of this new type of dipolar electrode for multi-focal electroretinograms.Methods In a comparative study,a new type of dipolar corneal contact lens electrode and the Jet corneal contact lens electrode were applied to the same eye of 15 volunteers (15 eyes) for multi-focal electroretinogram examination.The first order kernel was choosen.Mean response densities,amplitude and latency of P1 in rings 1-5 were recorded.Corneal fluorescein sodium dyeing was assessed after the examination,and the degree of comfort was evaluated with a questionnaire.Data were analyzed using paired t test.Results P1 response densities and amplitudes in rings 1-5 of the dipolar corneal contact lens electrode were lower than those of the Jet corneal contact lens electrode,but the tendencies of the response densities and amplitudes were almost the same.There was no significant difference in latency between the two kinds of electrodes in rings 2 to 5.Corneal fluorescein sodium dyeing was almost negative with both electrodes.The degree of comfort with the Jet electrodes was better than for the dipolar electrodes,but the difference was not significant.Conclusion Compared with the Jet electrode,the new type of dipolar electrode can also record correctly,and it is safe and comfortable for the cornea.The dipolar electrodes are more convenient and cheaper than the Jet electrodes,so they cannot only save time but also avoid cross infection. Key words: Corneal electrode; Dipolar; Electroretinography,multi-focal; Application