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Polarization Sensitive Retinal Tomography for Glaucoma Diagnosis (PSOCT)

This study has been completed.
National Eye Institute (NEI)
Information provided by (Responsible Party):
Courtney Frazier Swaney, University of Texas at Austin Identifier:
First received: October 14, 2010
Last updated: March 26, 2012
Last verified: March 2012

The proposed human clinical studies have three main objectives:

  1. To determine reproducibility of peripapillary birefringence maps and identify features that measure the health of the RNFL.
  2. To determine the normal variation in the birefringence maps with age.
  3. To develop and test a classifier for glaucoma based on the birefringence maps using a case-control clinical trial.

This study is a case-control study intended to optimize feature selection for a future multi-center blinded study. The proposed clinical study does not measure conversion from normal to glaucoma.


Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Cross-Sectional
Official Title: Polarization Sensitive Retinal Tomography for Glaucoma Diagnosis

Resource links provided by NLM:

Further study details as provided by University of Texas at Austin:

Primary Outcome Measures:
  • Sensitivity/specificity of PSOCT to classify glaucoma vs. non-glaucoma [ Time Frame: The time frame to assess the effectiveness of the diagnostic algorithm is 1 year ]
    Features from RNFL phase retardation and birefringence maps will be combined into a diagnostic algorithm to differentiate glaucoma vs. non-glaucoma

Enrollment: 85
Study Start Date: August 2007
Study Completion Date: March 2011
Primary Completion Date: December 2010 (Final data collection date for primary outcome measure)
Two groups will be studies: patients with glaucomatous visual field loss and age and gender matched normal patients without visual field loss

Detailed Description:
This study evaluates RNFL Birefringence in normal and glaucoma human subjects: The primate experimental glaucoma study will characterize the spatial and temporal dynamics of RNFL birefringence during glaucoma progression and establish an initial feature set and classifier for a case-control clinical study. The case-control clinical study will refine the initial feature set and classifier and use ROC analysis to test sensitivity and specificity of the feature set and classifier for discriminating between normal and glaucomatous human eyes. The feature set and classifier formulated in the case-control clinical study is a prerequisite for planning a large-scale longitudinal study. A large-scale longitudinal study to compare different approaches for detecting early glaucoma is outside the scope of the proposed research. Moreover, considering the large number of subjects required for statistical significance when the conversion rate from ocular hypertensive to glaucoma is low (<10%/year), a longitudinal study is best performed in a multi-institution clinical trial over several years.

Ages Eligible for Study:   40 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population
45 normal volunteers and 40 glaucoma patients (known visual field defects)with equal sex distribution between the ages of 40 and 80 will be recruited for this study by H. Grady Rylander, M.D. at The Eye Institute of Austin and grouped by age into the following categories: 40-49, 50-59, 60-69, 70-79. Every effort will be made to equalize the number of patients in each age category and to recruit volunteers representing the race distribution in our community. Maps of RNFLT, phase retardation, and RNFL birefringence will be acquired from individuals within each age category.

Inclusion Criteria: patient age between 40 and 80, visual acuity score of 20/40 or better; spherical refraction within ± 5 diopters, cylinder refraction within ± 3 diopters, ability to cooperate with study procedures and personnel and to perform tests reliably. Case-control assignment for the human clinical trials is based on medical and ocular history and on a comprehensive eye examination (including intraocular pressure history, standard disc photography and Humphrey-Zeiss 24-2 visual field test) by a glaucoma specialist.

Exclusion Criteria: discernable anomaly of the anterior chamber, uveitis, significant opacification of the cornea or crystalline lens, eyes with secondary glaucoma, eyes with pigmentary or pseudoexfoliation glaucoma, concurrent active eye disease in the study eye that may affect intraocular pressure or its measurement, patients on kidney dialysis, eyes with proliferative or severe nonproliferative retinopathy, retinal detachment, retinitis pigmentosa, or other significant retinopathy, eyes with field loss attributed to a non-glaucoma condition, dilated pupil diameter less than 4mm, and visual fields < 20 degrees.

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01222065

United States, Texas
Eye Institute of Austin
Austin, Texas, United States, 78757
Sponsors and Collaborators
Courtney Frazier Swaney
National Eye Institute (NEI)
Principal Investigator: Henry G Rylander, MD University of Texas at Austin
  More Information