April 2010
Volume 51, Issue 13
Free
ARVO Annual Meeting Abstract  |   April 2010
Assessment of Frames Averaging Algorithms for Optical Coherence Tomography
Author Affiliations & Notes
  • W. Wu
    Ophthalmology, University of Southern California and Doheny Eye Institute, Los Angeles, California
    College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China
  • O. Tan
    Ophthalmology, University of Southern California and Doheny Eye Institute, Los Angeles, California
  • D. Huang
    Ophthalmology, University of Southern California and Doheny Eye Institute, Los Angeles, California
  • Footnotes
    Commercial Relationships  W. Wu, None; O. Tan, Optovue, Inc, F; Optovue, Inc, P; D. Huang, Optovue, Inc., F; Optovue, Inc., I; Optovue, Inc., C; Optovue, Inc., P; Carl Zeiss Meditec, Inc., P; Optovue, Inc., R.
  • Footnotes
    Support  NIH grants R01 EY013516, NIH grants P30 EY03040, State Scholarship Fund of China 2009632110
Investigative Ophthalmology & Visual Science April 2010, Vol.51, 1780. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      W. Wu, O. Tan, D. Huang; Assessment of Frames Averaging Algorithms for Optical Coherence Tomography. Invest. Ophthalmol. Vis. Sci. 2010;51(13):1780.

      Download citation file:


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

      ×
  • Supplements
Abstract
 
Purpose:
 

Averaging several frames of optical coherence tomography (OCT) images can improve image quality by suppressing background and speckle noises, but can also introduce artifact if the registration of frames does not adequately remove motion error. The purpose of this study is to evaluate two commercially available frame-averaging algorithms, by post processing, in two RTVue software versions (Version 4.0.0.143 and Version 4.0.7.4).

 
Methods:
 

A Fourier domain OCT system (RTVue, Optovue, Inc. Fremont, CA), was used to scan 40 human subjects (20 normal and 20 glaucoma) with line scans (centered at fovea, scan length = 6mm). The RTVue postprocessing software registers and averages 16 consecutive frames for each line scan. Two versions of RTVue software (4.0.0.143 and 4.0.7.4) were evaluated. Three parameters were used to assess image quality. The noise variance evaluates noise suppression (smaller value better). The edge width evaluates edge blurring due to misregistration (smaller value better). The contrast to noise ration (CNR) evaluates contrast enhancement (larger value better). The Wilcoxon rank sum test was used to evaluate the significance of differences in image quality.

 
Results:
 

The noise variance, edge width, and CNR of frame-averaged images (both software versions) were significantly better than single frames (p < 0.001, Table 1). Frame averaging by software version 4.0.7.4 was significantly better than version 4.0.0.143 in terms of edge width (p = 0.04), but not the other 2 parameters (Table 1). The edge width parameter correlated with subjective assessment of image quality.

 
Conclusions:
 

Both version of frame-averaging software dramatically suppressed noise and increased contrast. Software version 4.0.7.4 preserves edge sharpness better than version 4.0.0.143, indicating better registration of image frames. Registration of image frames is critical to image quality and edge width is a good parameter for its evaluation.  

 
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • image processing • imaging/image analysis: non-clinical 
×
×

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.

×