April 2014
Volume 55, Issue 13
Jump To...
Free
ARVO Annual Meeting Abstract  |   April 2014
Dynamic Analysis on the Effects of Lighting Variation on Anterior Chamber Angle Metrics with Cirrus Spectral Domain Optical Coherence Tomography
Ken Marion; Moritz Niemeyer; Srinivas R Sadda; Vikas Chopra
Author Affiliations & Notes
  • Ken Marion
    DIRC, Doheny Eye Institute, Los Angeles, CA
  • Moritz Niemeyer
    DIRC, Doheny Eye Institute, Los Angeles, CA
  • Srinivas R Sadda
    DIRC, Doheny Eye Institute, Los Angeles, CA
  • Vikas Chopra
    DIRC, Doheny Eye Institute, Los Angeles, CA
  • Footnotes
    Commercial Relationships Ken Marion, None; Moritz Niemeyer, None; Srinivas Sadda, Allergan (C), Carl Zeiss Meditec (C), Carl Zeiss Meditec (F), Genentech (C), Optos (C), Optos (F), Optovue (F), Regeneron (C); Vikas Chopra, Allergan (C)
  • Footnotes
    Support None
Investigative Ophthalmology & Visual Science April 2014, Vol.55, 4838. doi:
  • Views
  • Share
  • Tools
    • Alerts
      User Alerts
      You are adding an alert for:
      Dynamic Analysis on the Effects of Lighting Variation on Anterior Chamber Angle Metrics with Cirrus Spectral Domain Optical Coherence Tomography
      You will receive an email whenever this article is corrected, updated, or cited in the literature. You can manage this and all other alerts in My Account
      The alert will be sent to:
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation
      Citation

      Ken Marion, Moritz Niemeyer, Srinivas R Sadda, Vikas Chopra; Dynamic Analysis on the Effects of Lighting Variation on Anterior Chamber Angle Metrics with Cirrus Spectral Domain Optical Coherence Tomography. Invest. Ophthalmol. Vis. Sci. 2014;55(13):4838.

      Download citation file:

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

      ×
    • Get Permissions
  • Supplements
Abstract
 
Purpose
 

To evaluate the impact of variations in ambient lighting conditions on the reproducibility and reliability of novel Schwalbe’s Line-based anterior chamber angle (ACA) metrics using the Cirrus spectral domain optical coherence tomography instrument.

 
Methods
 

The inferior irido-corneal angles of 25 normal eyes were imaged twice with the Cirrus SD-OCT under light-meter controlled conditions at five different light levels (measured with a light meter at camera/eye interface), as well as with and without the corneal illumination (CI) function. Thus in total, each eye was imaged 20 times for a total of 500 assessments. Schwalbe’s line angle opening distance (SL-AOD) and Schwalbe’s line trabecular-iris-space area (SL-TISA) were graded twice by masked, certified graders at the Doheny Imaging Reading Center using customized ImageJ grading software. Percent differences in measurements from the brightest to darkest ambient light levels (with or without CI) were computed. Intra- and inter-grader reproducibility was evaluated at each lighting level by absolute mean difference (AMD), absolute error (AE), mean percent difference (MPD), coefficient of variation (CV), intra-class correlation coefficient (ICC), spearman correlation (R2), and Bland-Altman plots.

 
Results
 

With the CI function ON, decreasing the ambient light level from 1.0 to 0.0 foot-candles decreased the average SL-AOD measurement from 394µm+/-137µm to 356µm+/-137µm (MPD 10.71%) and the average SL-TISA measurement from 297µm2+/-114µm2 to 261µm2+/-109µm2 (MPD 13.7%). With the CI function OFF, the average SL-AOD measurement decreased from 366µm+/-136µm to 329µm+/-122µm (MPD 10.9%) and the average SL-TISA measurement from 271µm2+/-113µm2 to 234µm2+/-98µm2 (MPD 15.8%). Intra- and inter-grader results showed excellent reproducibility at each light level with and without CI. Bland-Altman plots of all comparisons did not demonstrate any apparent bias, with similar repeatability at various SL-AOD and SL-TISA values.

 
Conclusions
 

Anterior chamber angle morphometrics are exquisitely sensitive to changes in ambient illumination and even the illumination generated by the OCT instrument. These findings highlight the importance of strictly controlling lighting conditions when studying anterior chamber geometry.

 
Figure 1: Mean ACA metrics at varied ambient light levels
View OriginalDownload Slide
 
Figure 1: Mean ACA metrics at varied ambient light levels
 
Figure 1: Mean ACA metrics at varied ambient light levels
Figure 1: Mean ACA metrics at varied ambient light levels
View OriginalDownload Slide
 
Table 1: Intra-/Inter-Grader Reproducibility
View OriginalDownload Slide
 
Table 1: Intra-/Inter-Grader Reproducibility
 
Table 1: Intra-/Inter-Grader Reproducibility
Table 1: Intra-/Inter-Grader Reproducibility
View OriginalDownload Slide
 
Keywords: 420 anterior chamber • 421 anterior segment • 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)  
© 2014, The Association for Research in Vision and Ophthalmology, Inc., all rights reserved. Permission to republish any abstract or part of an abstract in any form must be obtained in writing from the ARVO Office prior to publication.
Copyright © 2025 Association for Research in Vision and Ophthalmology.
×
×

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.

×
This site uses cookies. By continuing to use our website, you are agreeing to our privacy policy.Accept