Binocular single vision (BSV) allows us to perceive a single three-dimensional image from two eyes. BSV develops in infants from 1-6 months as they learn to fuse the images from each eye. For BSV to occur, the brain must fuse the slightly different images from each eye and the visual pathways must be normal. There are different grades of BSV including simultaneous perception, fusion, and stereopsis which allows depth perception. Abnormalities can cause double vision.

1. BINOCULAR
SINGLE VISION
MARIA SAEED

2. CONTENTS:
• Brief Introduction
• Development of BSV
• Pre-requisite of BSV
• Retinal Correspondence and types
• Grades
• Abnormalities of BSV

3. INTRODUCTION
• BSV is a type of vision in which two eyes is able to perceive a single
three-dimensional image of its surroundings.
• A state of simultaneous vision which is achieved by co-ordinated use of
both eyes so that the separate and slightly dissimilar images arising in each
eye as a single image.

5. DEVELOPMENT OF BSV:
• 1-3 months: superimpose images are formed.
• 3 months: binouclar fusion.
• 3-6 months: stereopsis.

6. PRE- REQUISITE OF BINOCULAR VISION:
• Accurate co-ordination between two eyes in all direction of gaze.
• Ability of the brain to cause fusion o two slightly different images.
• Normal Visual Pathway.

7. RETINAL CORRESPONDENCE:
• Retinal elements of two eyes that share a common subjective visual direction is
called retinal correspondence.
• Retinal correspondence is of two types:
Normal Retinal Correspondence.
Abnormal Retinal Correspondence.

9. GRADES OF BSV:
• There are 3 grades of binocular vision that are given by Worth:
Grade 1: Simultaenous Perception
Grade 2: Fusion
Grade 3: Steropsis

10. SIMULTANEOUS PERCEPTION:
• Silmutaneous perception exists when signal transmitted from two eyes to
the visual cortex are preceived at the same time.
• Ability to see two dismiliar objects simultaneously.
• It does not imply superimposition of both objects.

12. FUSION:
• It is ability of the two eyes to produce a composite picture from two
similiar pictures each of which is incomplete in a small detail.
• In other words, unification of visual objects into a single percpect that is
made possible by the simultaenous simulation of corresponding retinal
areas.

14. STEROPSIS:
• A greek word : stepos= solid, opsis= look.
• Viusal appreciation of three dimensions.
• Ability to obtain impression of depth by superimposition of rwo images of
same object, seen from two slightly different angle.
• Steropsis and depth perceptionare not synonymous.

16. DIPLOPIA:
• When non-corresponding retinal areas are not stimulated by similar stimuli.
• One object is seen at two different locations in the field.