This document discusses diplopia (double vision) from an orthoptic perspective. It defines diplopia and describes the requirements for binocular single vision. There are three main types of diplopia: physiological, pathological, and functional. Pathological diplopia can be binocular or monocular. The two most common mechanisms for diplopia are misalignment of the visual axes and abnormalities of the ocular media or refractive errors. A thorough history, examination, and testing are required to determine the type and cause of diplopia and guide treatment.

1. ORTHOPIC APPROACH TO
DIPLOPIA
Siraj Safi

2. Definition
 Diplopia or double vision is the subjective
complaint of seeing two images of an object
instead of one.

3. What does the faculty of BSV
require?
 Perfect ( or near perfect ) alignment of the
visual axes simultaneously on the object of
regard
 Perfect ( or near perfect ) retinal
correspondence
 Perfect central ( or paracentral ) fusional
capability.
 Perfect ( or near perfect ) optics to allow
only one image to be formed on the retina
and the same single image to be formed
on the other

4. Types of Diplopia ?
 Physiological
 Pathological
 Functional diplopia

5. F
F F
Uncrossed retinal disparity
Crossed retinal disparity
Corresponding points
Retinal Disparity

6. Pathalogical diplopia
 Binocular diplopia
 Moncular diplopia

7. Mechanism of Diplopia
 The two most common mechanisms for
diplopia are visual axis misalignment and
abnormalities of the ocular media or
refractive errors .

8. Binocular diplopia
 In ocular misalignment, the image of an
object that is being viewed does not fall on
fovea of both retinas.
 This causes binocular diplopia which
disappears on closing one eye

9. Homonymous (parallel) diplopia
F
F

10. Monocular Diplopia
 The abnormalities of the ocular media or
refractive errors lead to monocular diplopia
that persists in the affected eye even if the
other eye is closed.

11. Functional Diplopia
 Diplopia without any pathological cause is
termed functional.
 However, it is a diagnosis of exclusion and a
thorough examination and appropriate
investigations are mandatory to rule out a
pathological cause first.

12. Importance
 It is important to differentiate monocular
from binocular diplopia.
 The diagnosis of monocular diplopia usually
obviates the need for a detailed neurological
examination

13. Causes of Monocular Diplopia
 Refractive error
 Anomalies of the tear film
 Corneal defect (e.g., irregular astigmatism)
 Cataract
 Media opacities
 Retinal defects

14. Causes of Binocular Diplopia
 The causes are multifactorial but results most
commonly from an acquired misalignment of
the visual axis secondary to recent onset of
extraocular muscle paralysis.

15. History
A detailed history. Points
1. When and how did the double vision started?
2. Whether diplopia disappears or persists after
closing one eye?
3. Associated symptoms with double vision if any?
4. Is it constant in all gazes or more in a particular
gaze?
5. Is it more for far or near fixation?

16. HISTORY
6.Whether the images are horizontally, vertically
or obliquely separated?
7. Is the diplopia constant, intermittent or variable?
8.Whether diplopia worsens at the end of the day?
9. History of any trauma to eye, face, head or any
history of ocular surgery recent or in past.
10. Detailed history of systemic diseases like
diabetes mellitus, hypertension, thyroid
disorders, myasthenia gravis should be taken.

17. Leading questions
 In which direction of gaze are the images
maximally separated?
Diplopia is maximum ( separation of images)
in the field of action of the paralysed muscle.
 To which eye does the “outer” image belong?
The false image ( the image belonging to the
eye with the hypofunctioning muscle ) is
always peripherally situated

18. Clinical Evaluation
For monocular diplopia
 Pin hole test
 Refraction
 Anterior segment examination with slit lamp
 Detail fundus examination for retinal
disorders

19. The evaluation of binocular
diplopia
1. Abnormal head posture
2. Orbital and lid abnormalities
3. Extraocular muscle movements
4. Pupillary reactions
5. Neuromuscular junction examination (M.G)
6. Examination of cranial nerves especially
third, fourth and sixth cranial nerves

20. The evaluation of binocular
diplopia
7. Prism Bar CoverTest
8. Maddox rod test
9. Double Maddox RodTest
10. Diplopia charting (R/G goggles)
11. Paretic vs restrictive etiology
12. HessTest
13.Worth four light test

21. Diplopia Charting
 This test helps in recording the subjective
deviation by asking the patient to quantify
the separation between the double images,
dissociated by red green glasses.
Main points to be remembered are:
a. Maximum separation is in the quadrant in
which the muscle acts most (field of action)
b.The image that appears farthest, belongs to
the deviating eye
c.The image is displaced in direction of action
of paralysed muscle.

23. Interpretation
i. If two images are joined together—no diplopia
ii. If images are separated—confirms diplopia.
iii. Maximum separation is in the quadrant in
which (the muscle moves
the eye) the muscle is restricted.
iv.The image is displaced towards the field of
action of the paralyzed muscle.

24. Interpretation
v. If horizontal separation with uncrossed
images—esodeviation.
vi. If horizontal separation with crossed
images—exodeviation.
vii. If vertical separation with uncrossed
images—oblique muscles involved.
viii. If vertical separation with crossed image—
vertical recti muscle involved

25. Systemic Investigations
1. Blood sugar levels / HbA1C for Diabetes
Mellitus
2.Test for myasthenia gravis –
electromyography (EMG), nerve conduction
studies with a repetitive stimulation test and
anti - acetylcholine receptor antibodies
3.T3,T4,TSH for thyroid eye disease
4. CT scan / MRI of brain and orbit for thyroid
eye disease, any intracranial or orbital
pathology.

26. Treatment
1. Treat the underlying cause, wherever possible.
2. Correction of refractive errors if present.
3. Unilateral eye occlusion therapy with either an
eye patch or by blurring one lens of the patient’s
glasses with semi-opaque surgical tape.
4. Prisms are used for optical correction of
symptomatic binocular diplopia.
5. Orthoptic exercise (CI)
6. Surgery for strabismus can be done to restore
ocular alignment after a period of observation
for at least 06 months.

27. THANKYOU