Predictive value of visual evoked potentials in unilateral optic nerve injury

Forty-five patients with posttraumatic unilateral blindness were prospectively analyzed. The computed tomography scan was normal in all and an optic canal fracture was recorded in only one patient. Visual evoked potentials were performed within 48 hours of initial evaluation and repeated within 7 to 10 days. Five patients had normal visual evoked potentials and 15 patients had abnormal responses. No visual evoked potentials were recorded in 25 patients. Five patients with normal visual evoked potentials had good visual recovery. Thirteen of the 15 patients with abnormal responses also showed significant visual improvement. This study showed that positive visual evoked potentials were reliable in predicting the visual outcome; 90% of the patients with positive visual evoked potentials had complete or partial visual recovery.