Diplopia

Background

Eye movements by extra-ocular muscles and cranial nerve innervation

Monocular Diplopia

• Double vision that persists when one eye is closed
• Related to intrinsic eye problem

Binocular Diplopia

• Double vision that resolves when the other eye is closed
• Related to a problem with visual axis alignment

3 Main Causes Binocular Diplopia

• Eye Musculature Dysfunction
• Cranial Nerve Dysfunction
• Brainstem or Intracranial process

Clinical Features

Exam

• Determine Monocular vs Binocular
• Eval for Visual Field Defect
• Evalulate for Visual Acuity
• Determine if there is a Cranial Nerve Deficit
• Check extraocular muscle function
• Entrapment will show extraocular muscle restriction with extremes of gaze

• Multiple cranial nerve involvement suggests an intracranial process or cavernous sinus involvement
• Sudden painful or non painful onset suggest a vascular cause such as thrombosis, dissection, ischemia, or vasculitis
• Other neurodeficits should raise suspicion for a CVA or MS
• Systemic illness is more likely with meningitis involving the brainstem
• Bilateral symptoms are more likely with neuromuscular problems such as Miller Fischer syndrome, Botulism, or Myesthenia

Differential Diagnosis

Algorithm for the Evaluation of Diplopia

Monocular Diplopia

• Cataract
• Lens Dislocation
• Macular Disruption

Binocular Diplopia

• Basilar Artery Thrombosis
• Aneurysm
• Vertebral Artery Dissection
• Myasthenia Gravis
• Lambert-Eaton Syndrome
• Botulism
• Cavernous Sinus Thrombosis
• Brainstem Mass
• Intracranial Mass
• Miller Fischer variant Guillain-Barré
• MS
• Hyperthroid Proptosis
• Basilar Meningitis
• CVA
• Muscular Entrapment from Trauma

Workup

Monocular

• Slit Lamp Exam
  • Assess for Cataract
  • Lens Symmetric
  • Posterior Orbital Mass
  • Macular Dysruption
• Consider Ophthalmology Consult
• Consider Ocular Ultrasound

Binocular

• CT brain with and without contrast ± CTA neck to rule out dissection and intracranial mass
• MRI + DWI to if concern for CVA
• MRI±MRA if unable to classify intracranial process on initial contrast CT with contrast
• MRI if concerned for MS.

Management

• Neurology or Neurosurgical consult is warranted if evidence of an Intracranial bleed, Aneurysm or CVA
• Metabolic workup to rule out diabetes or cause of mononeuropathy
• If concern for basilar meningitis perform Lumbar Puncture

Disposition

Depends greatly on the cause of the diplopia

• Monocular Diplopia - can generally have opthalmology followup unless there is evidence of an open globe,

• Binocular Diplopia

Neurology or Neurosurgery consult is useful depending on the cause of diplopia

• Admit if:
  • CVA
  • Guillain-Barre
  • Botulism
  • ICH
  • Meningitis
  • Intracranial Mass with edema or shift
  • Aneurysm causing compression
  • Multiple Cranial Nerve Involvement

• Isolated Cranial Nerve III and VI palsy can be discharge if close Neurology followup and cause due to diabetes, microvascular ischemia and intracranial process ruled out

See Also

• Third Nerve Palsy

Sources

Comer RM, Dawson E, Plant G, Acheson JF, Lee JP: Causes and outcomes for patients presenting with diplopia to an eye casualty department. Eye 2007; 21:413-418