Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief:
Overview
Diplopia may be caused by disorders of the orbit, extraocular muscles, neuromuscular junction dysfuntion, paralysis of the oculomotor, trochlear and abducens nerves, and injuries affecting the central nervous system (CNS). Given the various causes of diplopia, it is important to differentiate between the different causes that lead to diplopia.
Differentiating Diplopia From Other Diseases
Diplopia may be caused by disorders of the orbit, extraocular muscles, neuromuscular junction dysfuntion, paralysis of the oculomotor, trochlear and abducens nerves, and injuries affecting the central nervous system (CNS). Given the various causes of diplopia, it is important to differentiate between the different causes that lead to diplopia. The following table differentiates between various causes of diplopia:[1]
Dilopia causing disorder
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Subcategory
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Mechanism
|
Distinguising Features
|
Exam Findings
|
Orbital disorder
|
Trauma
|
- Direct injury to the orbit or eye
|
- Ecchymosis
- Bone fracture
- Hematoma formation
- Altered mental status
|
|
Orbital apex mass
|
- Inflitration or mass effect in the orbital apex or cavernous sinus
- Compression of the oculomotor nerve
|
- Palsies of oculomotor, trochlear and/or abducens nerves
- Periorbital or facial numbness
- Retro-orbital pain
- Proptosis
- Signs of venous congestion
|
- Multi-directional horizantal and vertical diplopia
- Down and out pupil
- Pupillary dilation
- Deterioration of visual acuity
- Exophthamos
- Prominent choroidal folds
- Optic atrophy
- Bone destruction
|
Orbital cellulitis
|
- Spread of infection from contiguous sinuses (especially ethmoidal suinus)
- Culprit organisms include S. aureus and S. pneumoniae
|
- Proptosis
- Eyelid edema
- Ophthalmoplegia
- Ocular pain
- Presence of risk factors:
- Recent upper respiratory illness
- Sinus infection
- Younger age
- Retained foreign bodies within the orbit
- Trauma
- Immunosuppression
- Systemic infection
- Dental infections
|
|
Thyroid-associated ophthalmopathy (Grave's disease)
|
|
- Proptosis
- Restriction of elevation and abduction of the eyes
- Tachycardia
- Intolerance to heat
- Weight loss
- Insomnia
- Fatigue
- Diarrhea
|
- Dysthyroid orbitopathy (involvement of medial and inferior rectii muscles)
|
Extraocular muscle disorder
|
Thyroid-associated ophthalmopathy due to ocular surgery
|
|
|
|
Extraocular muscle injury or hematoma
|
|
|
|
Congenital myopathie
|
|
|
|
Mitochondrial myopathies,
|
|
|
|
Muscular dystrophy
|
|
|
|
Neuromuscular junction dysfunction
|
Myasthenia gravis
|
- Auto-antibodies against nicotinic acetylcholine receptors
|
- Fluctuating muscular weakness
- Ptosis
- Diplopia and weakness worsens with activity and improves with rest
|
|
Botulism
|
- Inhibition of acetylcholine release due to toxin at cholinergic synapse and pre-synaptic myoneural junction
|
- Dysathria
- Dysphagia
- Autonomic dysreflexia
- Pupillary dysfunction
|
|
Palsies of the third, fourth or sixth cranial nerves
|
Oculomotor nerve palsy
|
- Microvascular ischemia:
- Hemorrhage
- Tumor
- Vascular malformation
- Aneurysm
- Meningitis
- Multiple sclerosis
|
- Muscles affected:
- Medial, inferiorn superior rectii
- Inferior oblique muscle
- Levator palpebrae muscle
- Ciliary and constrictor pupillae muscles
|
- Multi-directional horizantal and vertical diplopia
- No diplopia on lateral gaze to the affected side
- Eyelid droop (ptosis)
- Down and out pupil
- Pupillary dilation
|
Trochlear nerve palsy
|
|
- Rotational diplopia that is worse on looking downwards and towards the nose
- Extorsion on downward gaze
|
Abducens nerve palsy
|
|
- Horizontal diplopia on gaze towards the affected side
- Lateral gaze palsy
|
Central nervous system injury (pathways and cranial nerve nuclei)
|
Basilar artery thrombosis
|
- Occlusive thrombosis of the basilar artery
- Brainstem ischemia
|
- Dysarthria
- Vertigo
- Cranial nerve palsies
- Presence of risk factors for ischemic stroke
|
|
Vertebral dissection
|
- Vertebrobasilar insufficiency
|
- Acute onset
- Neck pain
- Vertigo
- Presence of risk factors for vertebral dissection
|
|
Aneurysm
|
- Enlarging aneurysm causes direct compression of the cranial nerves
|
- Oculomotor nerve palsy
- Pupillary involvement
|
|
Wernicke's encephalopathy
|
- Thiamine deficiency leads to metabolic failure and tissue injury
|
- Nystagmus
- Ataxia
- Altered mental status
- Ophthalmoplegia
- Malnutrition
|
|
References
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