Diplopia

Background

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

problem with visual axis alignment

3 Main Causes

1. Eye Musculature Dysfunction
2. Cranial Nerve Dysfunction
3. Brainstem or Intracranial process

Clinical Features

Exam

1. Determine Monocular vs Binocular
2. Eval for Visual Field Defect
3. Evalulate for Visual Acuity
4. Determine if there is a Cranial Nerve Deficit
5. Check extraocular muscle function
6. 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

Monocular Diplopia

1. Cataract
2. Lens Dislocation
3. Macular Disruption

Binocular Diplopia

1. Basilar Artery Thrombosis
2. Aneurysm
3. Vertebral Artery Dissection
4. Myasthenia Gravis
5. Lambert-Eaton Syndrome
6. Botulism
7. Cavernous Sinus Thrombosis
8. Brainstem Mass
9. Intracranial Mass
10. Miller Fischer variant Guillain-Barré
11. MS
12. Hyperthroid Proptosis
13. Basilar Meningitis
14. CVA
15. 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

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