March 2012
Volume 53, Issue 14
ARVO Annual Meeting Abstract  |   March 2012
Measurement of Trabecular Meshwork Width using Swept Source Optical Coherence Tomography
Author Affiliations & Notes
  • Tin A. Tun
    Singapore Eye Research Institute, Singapore, Singapore
  • Mani Baskaran
    Singapore Eye Research Institute, Singapore, Singapore
  • Ce Zheng
    Singapore Eye Research Institute, Singapore, Singapore
    National Univ of Singapore, Singapore, Singapore
  • Tin Aung
    Glaucoma, Singapore National Eye Center, Singapore, Singapore
  • Footnotes
    Commercial Relationships  Tin A. Tun, None; Mani Baskaran, None; Ce Zheng, None; Tin Aung, None
  • Footnotes
    Support  Translational Clinical Research Partnership Grant from Biomedical Research Council, Singapore
Investigative Ophthalmology & Visual Science March 2012, Vol.53, 3267. doi:
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Tin A. Tun, Mani Baskaran, Ce Zheng, Tin Aung; Measurement of Trabecular Meshwork Width using Swept Source Optical Coherence Tomography. Invest. Ophthalmol. Vis. Sci. 2012;53(14):3267.

      Download citation file:

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

  • Supplements

Measurements of the angle width by ultrasound biomicroscopy (UBM) or anterior segment optical coherence tomography (ASOCT) take measurements 500 microns from the scleral spur, as the trabecular meshwork is assumed to lie within this distance. The aim of this study was to measure the trabecular meshwork width in the anterior chamber angle using Swept Source Optical Coherence Tomography (SS-OCT, SS-1000 CASIA, Tomey Corporation, Nogoya, Japan).


One hundred and forty-seven phakic eyes of 147 patients were recruited. All participants underwent dark room gonioscopy and SS-OCT angle imaging in one randomly selected eye. Angle closure was defined if the posterior trabecular meshwork (TM) not visible in 2 quadrants by gonioscopy. High definition SS-OCT images were corrected for refractive distortion by built-in CASIA program and customized software (Image J, NIH ImageJ; National Institutes of Health, Bethesda, Maryland) was utilised to measure TM width (distance between Scleral Spur and Schwalbe’s line), Angle Opening Distance (AOD500) and Trabecular Iris Space Area (TISA500). Linear regression analysis comparing average TM for age, gender, eye, angle status and conventional angle parameters was performed.


The majority of subjects were Chinese (141/147, 95.9%) with a mean age of 59.5 (8.97) years. There were more females (92/147, 62.6%) and subjects with open angles (118/147, 80.3%). The mean TM width was 0.777 (0.15) mm. The TM width of the right eye was significantly higher compared to the left eye {Mean diff 0.043 (0.16), Beta = -0.037 (95% CI -0.071, -0.003)}. The mean of inferior TM width was significantly wider compared to the other quadrants {inferior 0.888 (0.14) > superior 0.79 (0.14) > nasal 0.708 (0.14) and temporal (0.721 (0.1), p<0.001, analysis of variance}. There was no significant association found for angle parameters or demographic factors with TM width.


Inferior trabecular meshwork was widest compared to other quadrants. TM width was asymmetric in laterality and was not influenced by angle status. Quantitative angle measurements at 0.75mm instead of 0.5mm are more appropriate in the determination of angle closure using UBM or ASOCT.  

Keywords: trabecular meshwork • anterior segment • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) 

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.