Low Contrast Visual Evoked Potentials for Early Detection of Optic Neuritis

Soo-Hyun Park; Choul-Yong Park; Young Joo Shin; Kyoung Sook Jeong; Nam-Hee Kim

doi:10.3389/fneur.2022.804395

Low Contrast Visual Evoked Potentials for Early Detection of Optic Neuritis

Front Neurol. 2022 Apr 29:13:804395. doi: 10.3389/fneur.2022.804395. eCollection 2022.

Authors

Soo-Hyun Park¹, Choul-Yong Park², Young Joo Shin³, Kyoung Sook Jeong⁴, Nam-Hee Kim⁵

Affiliations

¹ Department of Neurology, Department of Critical Care Medicine, Department of Internal Hospital, Inha University, Incheon, South Korea.
² Department of Ophthalmology, Dongguk University-Seoul Graduate School of Medicine, Dongguk University Ilsan Hospital, Goyang, South Korea.
³ Department of Ophthalmology, Hallym University Medical Center, Seoul, South Korea.
⁴ Department of Occupational and Environmental Medicine, Wonju Severance Hospital, Wonju, South Korea.
⁵ Department of Neurology, Dongguk University-Seoul Graduate School of Medicine, Dongguk University Ilsan Hospital, Goyang, South Korea.

Abstract

Optic neuritis (ON) detection is important for the early diagnosis and management of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). However, the conventional high-contrast visual evoked potential (VEP) used for ON detection lacks sensitivity for identifying ON presenting as mild or unremarkable visual disturbance, which is common in first-episode ON. Therefore, this study aimed to investigate whether a change in contrast or check size improves the sensitivity of VEP to first-ever ON. In total, 60 patients with the demyelinating disease (29 MS and 31 idiopathic patients with ON) without ON or with first-ever ON at least 6 months prior and 32 healthy controls underwent neuro-ophthalmic evaluations. VEPs were induced using three pattern-reversal checkerboard stimuli having, respectively, 10% contrast with a check size of 32' (LC32 VEP), 100% contrast with a check size of 32' (HC32 VEP; conventional VEP), and 100% contrast with a check size of 16' (HC16 VEP). The receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) were calculated to determine the most appropriate VEP method for detecting optic nerve involvement. The optimal cut-off point was determined using the Youden index (J-index). The McNemar test was used to determine whether dichotomous proportions were equivalent. In comparison with first-ever ON eyes (n = 39) and healthy eyes (n = 64), LC32 VEP showed the highest AUC for discriminating ON (0.750, p < 0.001; 0.730 for HC32 VEP, p < 0.001; 0.702 for HC16 VEP, p = 0.001). In the first-ever ON group, LC32 VEP and conventional HC32 VEP were abnormal in 76.9 and 43.6%, respectively (McNemar, p < 0.001), and combining these tests did not improve sensitivity. These indicate that LC32 VEP is the most sensitive method for detecting first-ever ON. Visual evoked potential with 10% contrast stimuli was superior to conventional VEP for detecting first-ever ON. Thus, adding these LC stimuli might be helpful in identifying optic nerve involvement in ON with mild or unremarkable visual impairment.

Keywords: check size; high-contrast; low-contrast; multiple sclerosis; optic neuritis; visual acuity; visual evoked potentials.