Risk factors affecting the visual outcome in patients with indirect traumatic optic neuropathy.

Purpose: To evaluate the etiology and possible prognostic factors affecting the visual outcome in patients with indirect traumatic optic neuropathy (TON).

Methods: The records of patients with indirect TON were reviewed and compared the results of treatment with high doses of corticosteroids (Group 1) and simple observation without treatment (Group 2).

Results: The mean age at the time of injury was 34.7 ± 11.4 (18-58) years in Group 1 and 37.5 ± 17.7 (8-73) years in Group 2 (p = 0.513). The mean value for the first referral of the patient to the ophthalmology clinic following trauma was 2.4 ± 2.4 (1-10) days in Group 1 and 16.7 ± 13.9 (1-30) days in Group 2 (p = 0.004). The most common causes of trauma were road traffic collision (57.1 and 68%) in the Group 1 and 2, respectively (p = 0.606). The mean initial visual acuity was 0.03 ± 0.07 (0.00-0.30) in Group 1 and 0.17 ± 0.21 (0.00-0.80) decimal in Group 2 patients (p = 0.001). The mean visual acuity at the final follow-up was 0.21 ± 0.35 (0.00-1.00) and 0.46 ± 0.42 (0.00-1.00) in Group 1 and Group 2, respectively, indicating better initial and final visual acuity values in Group 2 (p = 0.022), and also a statistically significant recovery of visual acuity between initial and final values in both groups (p < 0.05). The most important determinant of the final visual acuity was initial visual acuity (p < 0.001; 95.0% CI: 0.792-2.096).

Conclusions: Our study demonstrated that road traffic collision is the leading cause of indirect traumatic optic neuropathy, and the best predictor of final visual acuity outcome is the initial visual acuity.