Computed Tomographic Evaluation of the Optic Canal in Sudden Traumatic Blindness

doi:10.1016/0002-9394(84)90693-7

American Journal of Ophthalmology

Volume 98, Issue 6, December 1984, Pages 751-755

https://doi.org/10.1016/0002-9394(84)90693-7 Get rights and content

Using computed tomographic scans and reformatted images of the optic canal region, we were able to define osseous abnormalities in nine patients with sudden traumatic blindness resulting from indirect trauma to the optic nerve. Six patients had optic canal fractures, two had fractures of adjacent structures, and one patient did not have a fracture. Patients received corticosteroid therapy, surgical decompression of the optic canal, both types of treatment, or no specific treatment for the nerve injury. Although there was no correlation between the abnormality identified by computed tomography and treatment results, our findings provided further evidence that a canal fracture is not necessary for injury of the optic nerve to occur. We recommend that patients with sudden visual loss after blunt head trauma undergo a computed tomographic scan of the optic canal region.

References (10)

A.S. Grove
Orbital trauma and computed tomography
Ophthalmology
(1980)
R.L. Anderson et al.
Optic nerve blindness following blunt forehead trauma
Ophthalmology
(1982)
F.B. Walsh et al.
S.J. Manfredi et al.
Computerized tomographic scan findings in facial fractures associated with blindness
Plast. Reconstr. Surg.
(1981)
B. Hughes
Indirect injury of the optic nerves and chiasm
Bull. Johns Hopkins Hosp.
(1962)

There are more references available in the full text version of this article.

Cited by (30)

Cosmetic surgery disaster: Blindness after rhinoplasty
2023, Journal Francais d'Ophtalmologie
Traumatic optic neuropathy-Clinical features and management issues
2015, Taiwan Journal of Ophthalmology
Citation Excerpt :
The intracranial portion of the optic nerve in close proximity to the falciform dural fold is the next most common site at risk of injury.5 In one report using computerized tomography (CT) imaging, about half of all TON cases were found to have an associated sphenoidal bone fracture, an indirect measure of the significant compressive forces involved at impact.6 However, both direct and indirect mechanisms can contribute to optic nerve damage, and a clear distinction is not always possible.
Traumatic optic neuropathy (TON) is an uncommon cause of visual loss following blunt or penetrating head trauma, but the consequences can be devastating, especially in cases with bilateral optic nerve involvement. Although the majority of patients are young adult males, about 20% of cases occur during childhood. A diagnosis of TON is usually straightforward based on the clinical history and examination findings indicative of an optic neuropathy. However, the assessment can be difficult when the patient's mental status is impaired owing to severe trauma. TON frequently results in profound loss of central vision, and the final visual outcome is largely dictated by the patient's baseline visual acuities. Other poor prognostic factors include loss of consciousness, no improvement in vision after 48 hours, the absence of visual evoked responses, and evidence of optic canal fractures on neuroimaging. The management of TON remains controversial. Some clinicians favor observation alone, whereas others opt to intervene with systemic steroids, surgical decompression of the optic canal, or both. The evidence base for these various treatment options is weak, and the routine use of high-dose steroids or surgery in TON is not without any attendant risks. There is a relatively high rate of spontaneous visual recovery among patients managed conservatively, and the possible adverse effects of intervention therefore need to be even more carefully considered in the balance.
Neuro-ophthalmologic diagnosis and therapy of central nervous system trauma
1999, Neurosurgery Clinics of North America
Careful examination and judicious use of neuroimaging will lead to the initiation of appropriate management for injuries of the afferent and efferent visual systems. This article concentrates on those aspects of neuroophthalmologic trauma that are most relevant to the neurosurgeon, particularly those disorders that are commonly faced when caring for acutely injured patients. Although direct injury to the orbit and globes can easily result in neuro-ophthalmologic disorders, it is less appreciated that distant head injury can similarly result in injury to the retrobulbar afferent visual pathways or cranial nerves. It is therefore necessary that the neurosurgeon be suspicious of both latent and manifest injuries to the neuro-ophthalmologic system after head trauma, and maintain awareness of the need for timely intervention in a subset of these disorders. Therefore, even patients with injuries removed from the eyes should be checked for visual problems, and, if any are detected, an ophthalmologist or neuro-ophthalmologist should be consulted.
Traumatic optic neuropathy
1994, Survey of Ophthalmology
Knowledge concerning the pathophysiologic mechanisms of traumatic optic neuropathy is limited. The optic nerve is a tract of the brain. Therefore, the cellular and biochemical pathophysiology of brain and spinal cord trauma and ischemia provide insight into mechanisms that may operate in traumatic optic neuropathy. The dosage of methylprednisolone (30 mg/kg/6 hours) which was successful in the National Acute Spinal Cord Injury Study 2 (NASCIS 2) evolved from the unique pharmacology of corticosteroids as antioxidants. The management of traumatic optic neuropathy rests on an accurate diagnosis which begins with a comprehensive clinical assessment and appropriate neuroimaging. The results of medical and surgical strategies for treating this injury have not been demonstrated to be better than those achieved without treatment. The spinal cord is a mixed grey and white matter tract of the brain in contrast to the optic nerve which is a pure white matter tract. The treatment success seen with methylprednisolone in the NASCIS 2 study may not generalize to the treatment of traumatic optic neuropathy. Conversely, if the treatment does generalize to the optic nerve, NASCIS 2 data suggests that treatment must be started within eight hours of injury, making traumatic optic neuropathy one of the true ophthalmic emergencies. Given the uncertainties in the treatment, ophthalmologists involved in the management of traumatic optic neuropathy are encouraged to participate in the collaborative study of traumatic optic neuropathy.
Ophthalmic complications associated with orthognathic surgery
1993, Journal of Oral and Maxillofacial Surgery
Ophthalmic complications are rare following maxillary osteotomies. Potential complications include a decrease in visual acuity, extraocular muscle dysfunction, neuroparalytic keratitis, and nasolacrimal problems involving both an increase or a decrease in tearing. Ophthalmic injuries appear to be primarily mediated through indirect injuries to neurovascular structures occurring from traction, compression, or contrecoup injuries from forces transmitted during the pterygomaxillary dysjunction using an osteotome or from fractures extending to the base of the skull or orbit associated with the pterygomaxillary dysjunction or the maxillary downfracture. A review of the literature of previous ophthalmic complications as well as eight new cases are reported. The possible etiologic basis for these injuries is discussed in detail as well as treatment possibilities when appropriate.
Orbital Roof Fractures in Childhood
1989, Ophthalmology
The authors documented 36 orbital roof fractures in 32 children over a 5-year period. With the aid of computed tomography (CT), 16 fractures were classified as isolated and 20 were found to be associated with more extensive damage to the skull. Isolated fractures typically occurred in younger children (mean age, 2.8 years) after relatively minor trauma, most often a fall from a height of less than 10 feet. Birth trauma was the cause in one case. Three fourths of the isolated fractures were linear; with extensive trauma, the orbital roof was usually comminuted. Upper eyelid hematoma characteristically developed hours after the traumatic event. There were no significant chronic disturbances of vision, motility, or lid function. Acute neurologic concerns were common, and two patients died, but full recovery was otherwise the rule. In two cases, late development of ocular pulsation led to CT demonstration of encephaloceles. Both of these children had comminuted roof fractures with displacement of bone fragments into the orbit. The authors conclude that fracture of the orbital roof is a common but frequently overlooked occurrence in childhood. Anatomic factors may account for differences in the effect of frontal impact at different ages.

View all citing articles on Scopus

: Reprint requests to Mitchel S. Berger, M.D., c/o Department of Neurological Surgery, Editorial Office, 350 Parnassus Ave., Suite 807, San Francisco, CA 94117.

View full text

Computed Tomographic Evaluation of the Optic Canal in Sudden Traumatic Blindness

Ophthalmology

Ophthalmology

Computerized tomographic scan findings in facial fractures associated with blindness

Plast. Reconstr. Surg.

Indirect injury of the optic nerves and chiasm

Bull. Johns Hopkins Hosp.