ISSN: 2155-9570
Sime Kabic, Dobrila Karlica Utrobicic, Hana Karlica
Purpose: To demonstrate the differences between visual evoked potential parameter values in recurrent optic neuritis in younger patients suffering from demyelinating diseases.
Design: Retrospective observational study-case series.
Methods: 18 patients aged 14-36 diagnosed with optic neuritis. Each patient underwent an eye examination, VEP test, neurologic examination and an adequate corticosteroid therapy, both in acute and recurrent optic neuritis.
Results: A statistically significant difference was observed in all subjects with regard to the values of visual acuity, amplitude and latency of the P100 wave in acute and recurrent optic neuritis (p<0.001). We also found a statistically significant spread between the eyes in recurrent optic neuritis (p=0.01). The mean value of visual acuity of the unaffected eyes in the first and second ON attack amounted to 1, while the mean value of visual acuity of the affected eyes amounted to 0.4 in the first attack and 0.1 in the second. The peak amplitude of the unaffected eyes was 15 μV in the first attack and 14.8 μV in the second. The amplitude of the affected eyes was 5.53 μV in the first attack and 2.92 μV in the second. The arithmetic mean latency of unaffected eyes was 101.2 ms in the first attack, while it amounted to 101.5 ms in the second. The latency value of affected eyes amounted to 120.5 ms in the first attack and 130.5 ms in the second. The decrease in visual acuity, amplitude reduction and the prolongation of P100 latency were statistically significantly higher in recurrent optic neuritis (p<0.001). The mean value of visual acuity of the affected eyes was lower by 0.3 in the second attack than in the first (z=3.86, p<0.001). The average amplitude of the affected eyes in the second attack was lower by 2.9 relative to the first (t=27.4; p<0.001). The average latency value of the affected eyes increased during the second attack relative to the first attack, namely by 9.9 (t=18.7, p<0.01).
Conclusion: The decrease in visual acuity, amplitude reduction and the prolongation of P100 latency in recurrent optic neuritis in patients with demyelinating disease are significant compared to the parameter values in acute optic neuritis.