Predictive value of the initial quantified relative afferent pupillary defect in 19 consecutive patients with traumatic optic neuropathy.

PURPOSE: To study the predictive value of the initial quantified relative afferent pupillary defect (RAPD) in patients with indirect traumatic neuropathy as it relates to final visual outcome.

METHODS

The RAPD was measured and quantified by neutral density filters in patients with unilateral indirect traumatic neuropathy. All patients were treated with megadose methylprednisolone by of the protocol established by the Second National Acute Spinal Cord Injury Study. Patients were followed twice daily during treatment and then at 3-month intervals.

RESULTS

Nineteen patients were enrolled over a 23-month period. Patients ranged in age from 12 to 78 years old; 18 of the 19 patients were male. No patient with an RAPD of 2.1 log units or greater had visual recovery to better than hand motion vision. The 7 patients with an initial RAPD of less than 2.1 log units showed improvement in their RAPD and were found to have vision of 20/30 or better during the follow-up period.

CONCLUSIONS

In patients treated with megadose methylprednisolone with an initial RAPD of less than 2.1 log units, visual acuity improved to 20/30 or better; however, patients with an initial RAPD of 2.1 or greater showed little visual improvement. The initial quantified RAPD appears to have a predictive value related to final visual outcome.