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Measuring Sensitivity to Viewpoint Change with and without Stereoscopic Cues
Published on: December 4, 2013
Real depth vs randot stereotests
David A Leske1, Eileen E Birch, Jonathan M Holmes
1Department of Ophthalmology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
Purpose:
To compare the performance of real depth and Randot stereotests in strabismic and nonstrabismic patients.
Design:
Observational case series.
Methods:
Stereoacuity was tested in 182 patients with a variety of strabismic conditions, using the Frisby-Davis 2 (FD2) distance stereotest, the near Frisby (nF) (both real depth tests), the Preschool Randot (nR), and Distance Randot (dR) tests (both based on Polaroid vectographs).
Results:
Patients appreciated finer disparities with the nF test than the nR test at near and with the FD2 test than the dR test at distance.
Conclusions:
The type of stereotest influences measurable thresholds, and the results from different tests are not interchangeable. The choice of test should depend on the question being asked; nF and FD2 would be appropriate for determining presence or absence of stereopsis and best measurable stereopsis. The more rigorous Randot tests would be appropriate for determining subtle changes.
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