Steroids for traumatic optic neuropathy
Abstract
Background
Traumatic optic neuropathy (TON) is an important cause of severe visual loss following blunt or penetrating head trauma. Following the initial injury, optic nerve swelling within the optic nerve canal can result in secondary retinal ganglion cell loss. Optic nerve decompression with steroids or surgical interventions or both has therefore been advocated as a means of improving visual prognosis in TON.
Objectives
The aim of this review was to examine the effectiveness and safety of using steroids in TON.
Search methods
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 1, 2007), MEDLINE (1966 to February 2007), EMBASE (1980 to February 2007), LILACS (March 2007) and NRR (Issue 1, 2007). We also searched the reference lists of included studies, other reviews and book chapters on TON to find references to additional trials. The Science Citation Index was used to look for papers that cited the studies included in this review. We did not manually search any journals or conference proceedings. Trial investigators and experts in the field were contacted to identify additional published and unpublished studies. There were no date or language restrictions in the electronic searches for trials.
Selection criteria
We planned to include only randomised controlled trials (RCTs) of TON in which any steroid regime, either on its own or in combination with surgical optic nerve decompression, was compared to surgery alone or no treatment.
Data collection and analysis
Two review authors independently assessed the titles and abstracts identified from the electronic searches.
Main results
No studies were found that met our selection criteria and therefore none were included for analysis.
Authors' conclusions
There is a relatively high rate of spontaneous visual recovery in TON and no convincing data that steroids provide any additional benefit over observation alone. Recent evidence also suggests a possible detrimental effect of steroids in TON and further studies are urgently needed to clarify this important issue. Based on the current literature, TON cases presenting more than eight hours after the initial injury should not be treated with steroids. The decision to initiate treatment for patients seen within the eight‐hour window remains controversial and the supporting evidence is weak. Each case therefore needs to be assessed on an individual basis and proper informed consent is paramount. An adequately powered RCT of steroids in TON poses difficult challenges and is probably not feasible.
PICOs
Plain language summary
Steroids in the treatment of traumatic optic neuropathy
The optic nerve transmits visual information from the eye to the brain and traumatic optic neuropathy (TON) refers to any injury to the optic nerve secondary to trauma. After the optic nerve has been injured, it becomes more swollen and this can lead to further damage. Traumatic optic neuropathy often results in severe visual loss and the vast majority of affected people are young males in their thirties. Since the early 1980s, steroids have been used in an attempt to reduce the abnormal swelling that follows an injury to the optic nerve and improve visual recovery. However, the role of steroids in TON is controversial and clinicians remain divided over the best management strategy. No randomised controlled trials of steroids in TON were identified and the recommendations in this review are based on a critical analysis of the available evidence in the medical literature. There is a relatively high rate of spontaneous visual recovery in TON and no convincing data that steroids provide any additional benefit over observation alone. Traumatic optic neuropathy cases presenting more than eight hours after the initial injury should not be treated with steroids. An argument could be made to start treatment in the first eight hours but the supporting evidence is weak. Each case needs to be assessed on an individual basis and the clinician must ensure that proper informed consent has been obtained. The patient needs to be made fully aware of the possibility of a serious adverse reaction, although rare, to steroids. Furthermore, recent studies have highlighted possible detrimental effects of steroids when used in brain and spinal cord injuries and these new lines of evidence need to be considered seriously. It is unlikely that a randomised controlled trial of steroids in TON will ever be carried out.
