June 2021
Volume 62, Issue 8
Open Access
ARVO Annual Meeting Abstract  |   June 2021
Spatial averaging effects on multifocal ERG amplitudes
Author Affiliations & Notes
  • Su-Yuan Yu
    USF Health Morsani College of Medicine, Tampa, Florida, United States
  • Sara Bijan
    Ophthalmology, USF Health Morsani College of Medicine, Tampa, Florida, United States
  • Gaurav Kiri
    USF Health Morsani College of Medicine, Tampa, Florida, United States
  • Swetangi Bhaleeya
    Ophthalmology, USF Health Morsani College of Medicine, Tampa, Florida, United States
  • Radouil T Tzekov
    Ophthalmology, USF Health Morsani College of Medicine, Tampa, Florida, United States
  • Footnotes
    Commercial Relationships   Su-Yuan Yu, None; Sara Bijan, None; Gaurav Kiri, None; Swetangi Bhaleeya, None; Radouil Tzekov, None
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science June 2021, Vol.62, 608. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Su-Yuan Yu, Sara Bijan, Gaurav Kiri, Swetangi Bhaleeya, Radouil T Tzekov; Spatial averaging effects on multifocal ERG amplitudes. Invest. Ophthalmol. Vis. Sci. 2021;62(8):608.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose : The purpose of this study was to evaluate the effect of spatial averaging on the multifocal electroretinography (mfERG) averaged ring amplitudes in patients screened for hydroxychloroquine (HCQ) toxicity.

Methods : This was a retrospective review of the records of patients screened for HCQ retinopathy at the USF Eye Institute (University of South Florida) during the period of 2015-2020. Only the records of patients referred internally were used. Patients were tested binocularly with Diagnosys mfERG system (Diagnosys LLC, Lowell, MA) using 61 hexagons grouped in five rings. The effects of the lowest level (level 1, or 4%) of spatial averaging on the mfERG P1 and N2 amplitude ring averaged values were evaluated.

Results : The records of 40 patients (4 males, 36 females) aged 54.4 ± 14.1 yrs. were selected for analysis. The use of spatial averaging had a differential effect on different rings. The effect was most pronounced on ring #1 (central element) amplitudes: for P1 the median change was (right/left eyes) –2.3/-1.7 nV/d2 (-13.3%/-12.1%); for N2 the median change was -2.5/-1.8 nV/d2 (-13.6%/-11.9%) and this decrease was significantly different than 0 for all comparisons (p<0.001, one sample Wilcoxon test). In contrast, the effect on the rest of ring amplitudes was small, the median absolute effect was either 0 or 0.1 nV/d2 (median % change was < 2.5%), although for ring #4 values this change was significant (p<0.02, one sample Wilcoxon test), except for N2 amplitude left eyes. The analysis of percent change vs. amplitude demonstrated no linear relationship for P1, while there was a negative relationship for N2 (ring #1, #2 and #3 left eyes and ring #1 left eyes), however, the presence of outliers was noted and once these were removed, the relationship remained significant only for ring #1 left eyes (R2 = 0.1347, p=0.0198).

Conclusions : For both P1 and N2 amplitudes spatial averaging has a substantial effect, especially on the amplitude of the central element (ring #1). As this is an mfERG amplitude is an important parameter, which could affect the interpretation of the results, use of spatial averaging should be avoided when analyzing mfERG results for HCQ screening.

This is a 2021 ARVO Annual Meeting abstract.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×