May 2008
Volume 49, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2008
The Validity of Screening for Glaucomatous Optic Nerve Damage Using GDx Variable Cornea Compesation (VCC) Scanning Laser Polarimetry (SLP) With VCC in High Risk Populations
Author Affiliations & Notes
  • A. Ciobanu
    Ophtalmology, Hopital Maisonneuve-Rosemont, Institute of Glaucoma Montreal, Centre de Recherche Guy Bernier, Montreal, Quebec, Canada
  • A. K. Fansi
    Ophtalmology, Hopital Maisonneuve-Rosemont, Institute of Glaucoma Montreal, Centre de Recherche Guy Bernier, Montreal, Quebec, Canada
  • P. Harasymowycz
    Ophtalmology, Hopital Maisonneuve-Rosemont, Institute of Glaucoma Montreal, Centre de Recherche Guy Bernier, Montreal, Quebec, Canada
  • Footnotes
    Commercial Relationships  A. Ciobanu, None; A.K. Fansi, None; P. Harasymowycz, None.
  • Footnotes
    Support  None.
Investigative Ophthalmology & Visual Science May 2008, Vol.49, 4643. doi:https://doi.org/
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      A. Ciobanu, A. K. Fansi, P. Harasymowycz; The Validity of Screening for Glaucomatous Optic Nerve Damage Using GDx Variable Cornea Compesation (VCC) Scanning Laser Polarimetry (SLP) With VCC in High Risk Populations. Invest. Ophthalmol. Vis. Sci. 2008;49(13):4643. doi: https://doi.org/.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose: : To evaluate whether scanning laser polarimeter GDx VCC is a valid tool for the detection of glaucomatous optic nerve damage.

Methods: : This was a prospective, observational, cross-sectional, non-consecutive, population study that took place in Montreal, Quebec, Canada and focused on "high risk" groups for open angle glaucoma development. 240 (480 eyes) subjects were enrolled during a 12 months period. Subjects underwent these tests: FDT, GDx VCC, a standard ophthalmologic examination, including gonioscopy, intraocular pressure, central corneal pachymetry, optic disc grading and fundoscopy.Outcomes measures included positive/negative Likelihood Ratios (LR), sensitivities and specificities, as well as positive/negative predictive values (PPV) of the nerve fiber indicator (NFI) parameter at a cut-off value 30, 35 and 40. Gold-standard definitions of glaucoma (Gold Standart 1- positive vs probable, possible, negative; Gold 2 - positive, probable vs possible, negative; Gold 3 - positive, probable, possible vs negative) varied depending on whether suspects were classified with normals, suspects or glaucoma, based on optic nerve appearance and on FDT results.

Results: : Of the original 240 patients examined, 19(8%) were found to have glaucoma. Depending on gold-standard definitions for glaucoma, Specificity ranged from 90% to 98%, Sensitivity from 10% to 100%, PPV from 14% to 65%, NPV from 56% to 100%.In all three test positive groups (NFI>=30,35,40) there was a good correlation between clinical based diagnoses:NFI>=30Gold 1 OS Khi=24, p<0.002; Gold 2 Khi=23, p<0.000, Gold 3 Khi=7, p<0.012Gold 1 OD Khi=27, p<0.001; Gold 2 Khi=14, p<0.005, Gold 3 Khi=3, p<0.072Gold 1 OS or OD Khi=37, p<0.000 Gold 2 Khi=32, p<0.000, Gold 3 Khi=5, p<0.028NFI>=35Gold 1 OS Khi=17, p<0.013 Gold 2 Khi=5, p<0.060, Gold 3 Khi=3, p<0.083Gold 1 OD Khi=33, p<0.001 Gold 2 Khi=18, p<0.003, Gold 3 Khi=4, p<0.037Gold 1 OS or OD Khi=18, p<0.005 Gold 2 Khi=17, p<0.001, Gold 3 Khi=3, p<0.099NFI>=40Gold 1 OS Khi=27, p<0.006 Gold 2 Khi=3, p<0.127, Gold 3 Khi=3, p<0.106Gold 1 OD Khi=19, p<0.011 Gold 2 Khi=5, p<0.084, Gold 3 Khi=2, p<0.143Gold 1 OS or OD Khi=11, p<0.029 Gold 2 Khi=7, p<0.030, Gold 3 Khi=2, p<0.172

Conclusions: : This study suggests that a glaucoma screening program may be more effective in detecting POAG when targeting high risk populations. GDxVCC may prove to be a useful tool in detecting glaucomatous optic nerve damage, and could be used as part of a complete glaucoma screening protocol.

Keywords: nerve fiber layer • optic nerve • imaging/image analysis: 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.

×