title: [Comparative analysis of first and second order kernels of multifocal retinogram in normal subjects].
abstract: OBJECTIVE
  To compare the features of waveform and retinal distribution between first order kernel (FOK) and second order kernel (SOK) of multifocal electro retinogram (mfERG) in normal subjects.
  
  
  METHODS
  The mfERG were recorded in 17 normal eyes. The recordings were finished by the VERIS Science 4.0 system, with the condition of 96% contrast and 103 hexagons stimulating pattern.
  
  
  RESULTS
  Compared with the FOK, the waveform of SOK was complex with more wavelets. Generally, there were 3 positive and 3 negative waves in the first slice of SOK, and 4 positive and 4 negative in the second slice of SOK. Except the latencies, the retinal distributions of amplitude responses of FOK and SOK were almost the same as the following. The amplitude densities from central hexagon were the highest, and gradually decreased as the acentric degree increased. The amplitudes were larger in upper and temporal retina than those of lower and nasal retina. But the total energy of it was much smaller than that of FOK.
  
  
  CONCLUSIONS
  The features of retinal distribution of SOK were almost the same as FOK in normal people. It needs further research on whether it has the specificity for some kinds of fundus diseases or not.
authors.affiliation: Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China.
authors.forename: Guangwei
authors.initials: G
authors.lastname: Luo
authors.forename: Futian
authors.initials: F
authors.lastname: Jiang
authors.forename: Shixian
authors.initials: S
authors.lastname: Long
authors.forename: Shizhou
authors.initials: S
authors.lastname: Huang
authors.forename: Dezheng
authors.initials: D
authors.lastname: Wu
authors.forename: Lezheng
authors.initials: L
authors.lastname: Wu
mesh_terms: D000328:Adult; D004596:Electroretinography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000502:physiology*