Tests for stereopsis

Special Thanx to Mrs Haseela Hassan(2010-14 Batch) Alsalama College Of Optometry,Perinthalmanna)

1. Optom.Askar.PK
TESTS FOR STEREOPSIS
31
ST
DEC 2011

2. STEREOPSIS
Binocular visual depth perception
based on retinal rivalry.
It can be measured quantitatively in
seconds of arc.

3. Local stereopsis-This is detected with
stereogramsthat have individual elements
such as lines, edges or contours, such as
the Wirtcircles found in the Titmus
stereo test .
Global stereopsis-This is detected
using random dot stereogramssuch as the
Lang I and II, and the TNO test.

4. Two-Pencil Test
Synaptophore or Major
Amblyoscope
Stereogram
Titmus Stereo Test
Random-Dot Stereograms
TNO Test
Lang Test

5. Key points
Good illumination is required.
Sufficient presentation time is
needed to allow appreciation of the
disparity.

6. LANG'S TWO -PENCIL TEST
Qualitative measurement..
The test is performed with
both eyes open and then with
the 'weaker' eye covered.
The responses are compared.

7. SYNAPTOPHORE
MAJOR AMBLYOSCOPE

8. STEREOPSIS SLIDES

10. The object seen in depth, which has
the least disparity, denotes the
patient’s stereoscopic threshold.

11. TNO TEST
Consists of seven plates: three gross
stereo plates, one suppression plate and
three graded plate
Ranging from 480 to 15 seconds of arc.

12. PLATE I

13. PLATE II

14. PLATE III

15. PLATE IV

17. PLATE V
480
240

18. PLATE VI
120
60

19. PLATE VII
30
15

20. LANG STEREOTEST
The targets are seen alternately by each eye, and
are then fused to create the disparity.
The Lang I test -a cat, a star and a car –
1200 to 550 seconds of arc.

21. The Lang II test -a star ,a car, an elephant and a
moon
200 seconds of arc.

22. FRISBY STEREOTEST
Random triangular shapes
Three plastic plates of different thickness: 6, 3
and 1 mm.
Each plate has four squares of shapes

600 to 15 seconds of arc.

24. TITMUS STEREOTEST
3000 seconds of arc
The second plate consists of nine sets of four
circles (Wirt circles).
800 to 40 seconds of arc.

26. RANDOT STEREOTEST
Six random dot shapes.
500 to 250 seconds of arc.
The second plate consists of circles, measuring
from 400 to 200seconds of arc and three rows of
animals with disparities from 400 to 100 seconds of
arc.

27. REFERENCE
Practical Binocular Vision Assessment…
BUTTERWORTH,,HEINEMANN…..
Binocular Vision and Ocular Motility
THEORY AND MANAGEMENTOF STRABISMUS
Gunter K. von Noorden, MD..Emilio C. Campos, MD…Mosby