Radiographic Optic Nerve Findings and Their Clinical Implications in the Setting of Craniomaxillofacial Trauma

Abstract

Purpose: Computed tomography (CT) scans obtained in the setting of facial trauma often report aberrations in neural anatomy, such as optic nerve stretching. While these findings have not yet been correlated with clinical findings, they raise concern for traumatic optic neuropathy (TON). This study aims to correlate radiographic optic nerve abnormalities with clinical findings in the setting of craniomaxillofacial trauma. Methods: Patient charts were queried based on ICD-9 codes for the presence of an orbital fracture. Patients were included if the CT report mentioned an anatomic abnormality of the optic nerve. Patients who expired within 24 hours of arrival, had an open globe injury, or who were not able to participate in a visual exam were excluded. An additional matched cohort of patients with orbital fractures and without optic nerve abnormalities was selected. The primary endpoint was a clinical diagnosis of TON, and secondary endpoints included the need for ophthalmologic intervention and the presence of abnormal visual acuity. Results: One-hundred and eight patients were included in the study (54 per group). Radiographic optic nerve stretching was not associated with an increased risk of TON (OR: 2.22, 95% CI: 0.71-7.02); however, it was associated with increased risk for abnormal visual acuity (OR: 2.24, 95% CI: 1.01-4.99). There was no increased need for any ophthalmologic intervention (OR: 1.93, 95% CI: 0.86-4.31). Conclusions: Alterations in orbital anatomy on CT are common after orbital fracture and may inappropriately raise concern for TON. This in turn may prompt interfacility transfer and/or emergent ophthalmology consultation. This study demonstrates that radiographic stretching of the optic nerve does not increase the odds for TON in the setting of orbital fractures. While patients with abnormal optic nerve findings did have a higher rate of abnormal visual acuity, this is a common, multifactorial finding in this setting.