Diplopia

Dr. Njambi Ombaba, Paediatric ophthalmologist

University of Nairobi

Objectives

To understand types of diplopia

To be able to identify the various causes of diplopia

To outline the approach to diplopia management

Definition of diplopia Seeing two images instead

of one

The images can be side by side, on top of each other or both

Loss of simultaneous use of both eyes with bifoveal fixation

Conditions for Bifoveal fixation

Perfect (or near perfect) alignment of retinal receptors

Perfect (or near perfect )retinal correspondence

Perfect (or near perfect) alignment of the visual axes

Perfect(or near perfect)optics for clear images

Perfect central(or paracentral) fusional capability

Types of diplopia

Binocular diplopia

Monocular diplopia

Monocular diplopia

• Abnormalities of refractive media

• Typically improves with a pinhole

Persistent double vision when one eye is occluded

Monocular diplopia

Binocular diplopia

Present when the two eyes are open

Results from misalignment of visual axis

Relieves by closing either eye

The extraocular muscles

Nerve supply All by CN3 except LR6SO4

Actions of the extraocular muscles

Actions of the extraocular muscles

Vertical Recti- Primary action abducted 23 degreesOblique's: Primary action adducted 51degrees

Yoke muscles combinations

Causes of Binocular diplopia

Cranial nerve palsies – stroke, DM, HTN, neoplasms, aneurysms

Convergence / accommodation- insufficiency spasms

Trauma- orbital, intracranial

Muscle / Neuromuscular junction- Thyroid, Myasthenia

Decompensating phoria

Previous cataract surgery

Idiopathic / physiological

Localization of cranial nerve palsies

Parks-Bielschowsky three-step test for vertical deviations

R-G- B

Approach to a Patient with Diplopia

Key questions during evaluation

Monocular or binocular diplopia

Horizontal ,vertical, angular diplopia

Worse for near or distance

Change in head position- turn / tilt

Gaze where images are more separated

Evaluation?

Monocular

Ocular

media

Cortical polyopia

Psychogenic

Binocular

Comitant eye deviation

Non Comitant deviation

Key clues in binocular diplopia

Abnormal head position

Vision better at certain gazes

Obvious misalignment of eyes

Proptosis

Ptosis

Nystagmus

Clues for Restrictive causes

•Proptosis

•Graves disease

•Orbital trauma

•Retrobulbar injections

•Enophthalmos

Differentiating clues

Restrictive

• Mechanical restriction on FDT

• Increase IOP at eccentric gaze

• Normal saccades

• Ductions equal to versions

Paretic

• Free EOMM on FDT

• No change in IOP

• Slower saccades

• Ductions greater than versions

Versions and Ductions

Versions

Ductions

Institute appropriate management

Relief of diplopia Specific to pathology

Classify the Diplopia

Monocular Binocular ( Restrictive / Paretic)

Recognise the diplopia and accompanying features

History Examination / Tests

Examination guide

Monocular

Slit lamp examination

Fundoscopy

Brain pathology

Binocular

Strabismus / orthoptic assessment

Extraocular motility

Diplopia charting

Associated features; AHP proptosis, ptosis

Diplopia charting

Additional assessment

Relief of diplopia

Eye Patch

Glasses with filters or prisms

Contact lenses

Botox injections

Strabismus surgery

Treatment of specific cause