Traumatic optic neuropathy
Background
- Acute injury to the optic nerve from direct or indirect trauma resulting in vision loss
- Caused by indirect injury to the optic nerve (intracanalicular portion) from transmitted shock from an orbital impact
- Can also be caused by directly by penetrating injury or from bony fragments in the optic canal or orbit, or orbital hemorrhage and optic nerve sheath hematoma
Pathophysiology
- Indirect: Hypothesized to result from shearing injury to the intracanalicular portion of optic nerve, which can cause axonal injury or disturb the blood supply of the optic nerve
- Direct: Presumed to be the result of tissue disruption secondary to foreign body or bony fragments impacting the optic nerve
Clinical Features
History
- Acute unilateral vision loss, decreased color sensation, and/or visual field deficit after blunt or penetrating trauma
- Complaints may be delayed due to the impact of and treatment for other concomitant head injuries
Physical Exam
- External eye exam may show signs of orbital trauma or fracture (soft tissue edema, hematoma, step-off on palpation of orbital rim)
- Decreased visual acuity and an afferent pupillary defect (in unilateral cases)
- On funduscopy, the initial optic nerve head assessment will be normal. Optic atrophy may be seen 3-6 weeks after trauma.
Differential Diagnosis
Posterior ischemic optic neuropathy
Optic neuritis
Optic nerve avulsion
Non-organic vision loss
Pre-/intra-/subretinal hemorrhage
Choroidal Rupture
Commotio retinae
Evaluation
Workup
- Non-contrast head and face (including orbits) CT
Diagnosis
- Primarily a clinical diagnosis
Management
- Ophthalmology consult
- Generally, no acute interventions are known to change prognosis
Contraindicated
- Corticosteroids not helpful[1]
- Surgical intervention has not shown to be beneficial, although some support the use of surgery in certain scenarios (e.g. bony fragment abutting optic nerve or optic nerve sheath hematoma)
Disposition
- Outpatient ophthalmology follow up
Prognosis
- Visual improvement in only about 50% of patients
See Also
External Links
References
- ↑ Levin, L.A., et al., The treatment of traumatic optic neuropathy: the International Optic Nerve Trauma Study. Ophthalmology, 1999. 106(7): p. 1268-77.