Elodie Nerrant1, Lucie Abouaf, Frédéric Pollet-Villard, Anne-Laure Vie, Sandra Vukusic, Julien Berthiller, Bettina Colombet, Alain Vighetto, Caroline Tilikete. 1. Hospices Civils de Lyon (EN, LA, FP-V, A-LV, AV, CT), Neuro-Ophthalmology and Neuro-Cognition Unit, Hôpital Neurologique Pierre Wertheimer, Bron, France; Lyon I University (EN, SV, JB, AV, CT), Lyon, France; Service de Neurologie, Sclérose en Plaques, Pathologies de la Myéline et Neuro-Inflammation, Hôpital Neurologique Pierre Wertheimer, Bron, France; INSERM U1028 CNRS UMR5292 Lyon Neuroscience Center, Team ImpAct (AV, CT) and Observatoire Français de la Sclérose en Plaques (SV), Bron, France; Hospices Civils de Lyon (JB), Pôle Information Médicale Evaluation Recherche Unit, Equipe d'Accueil 4129, Bron, France; and Hospices Civils de Lyon (BC), Pharmacie Department, Hôpital Neurologique Pierre Wertheimer, Bron, France.
Abstract
BACKGROUND: The most common causes of acquired pendular nystagmus (APN) are multiple sclerosis (MS) and oculopalatal tremor (OPT), both of which result in poor visual quality of life. The objective of our study was to evaluate the effects of memantine and gabapentin treatments on visual function. We also sought to correlate visual outcomes with ocular motor measures and to describe the side effects of our treatments. METHODS: This study was single-center cross-over trial. A total of 16 patients with chronic pendular nystagmus, 10 with MS and 6 with OPT were enrolled. Visual acuity (in logarithm of the minimum angle of resolution [LogMAR]), oscillopsia amplitude and direction, eye movement recordings, and visual function questionnaires (25-Item National Eye Institute Visual Functioning Questionnaire [NEI-VFQ-25]) were performed before and during the treatments (gabapentin: 300 mg 4 times a day and memantine: 10 mg 4 times a day). RESULTS: A total of 29 eyes with nystagmus were evaluated. Median near monocular visual acuity improved in both treatment arms, by 0.18 LogMAR on memantine and 0.12 LogMAR on gabapentin. Distance oscillopsia improved on memantine and on gabapentin. Median near oscillopsia did not significantly change on memantine or gabapentin. Significant improvement in ocular motor parameters was observed on both treatments. Because of side effects, 18.8% of patients discontinued memantine treatment-one of them for a serious adverse event. Only 6.7% of patients discontinued gabapentin. Baseline near oscillopsia was greater among those with higher nystagmus amplitude and velocity. CONCLUSIONS: This study demonstrated that both memantine and gabapentin reduce APN, improving functional visual outcomes. Gabapentin showed a better tolerability, suggesting that this agent should be used as a first-line agent for APN. Data from our investigation emphasize the importance of visual functional outcome evaluations in clinical trials for APN.
RCT Entities:
BACKGROUND: The most common causes of acquired pendular nystagmus (APN) are multiple sclerosis (MS) and oculopalatal tremor (OPT), both of which result in poor visual quality of life. The objective of our study was to evaluate the effects of memantine and gabapentin treatments on visual function. We also sought to correlate visual outcomes with ocular motor measures and to describe the side effects of our treatments. METHODS: This study was single-center cross-over trial. A total of 16 patients with chronic pendular nystagmus, 10 with MS and 6 with OPT were enrolled. Visual acuity (in logarithm of the minimum angle of resolution [LogMAR]), oscillopsia amplitude and direction, eye movement recordings, and visual function questionnaires (25-Item National Eye Institute Visual Functioning Questionnaire [NEI-VFQ-25]) were performed before and during the treatments (gabapentin: 300 mg 4 times a day and memantine: 10 mg 4 times a day). RESULTS: A total of 29 eyes with nystagmus were evaluated. Median near monocular visual acuity improved in both treatment arms, by 0.18 LogMAR on memantine and 0.12 LogMAR on gabapentin. Distance oscillopsia improved on memantine and on gabapentin. Median near oscillopsia did not significantly change on memantine or gabapentin. Significant improvement in ocular motor parameters was observed on both treatments. Because of side effects, 18.8% of patients discontinued memantine treatment-one of them for a serious adverse event. Only 6.7% of patients discontinued gabapentin. Baseline near oscillopsia was greater among those with higher nystagmus amplitude and velocity. CONCLUSIONS: This study demonstrated that both memantine and gabapentin reduce APN, improving functional visual outcomes. Gabapentin showed a better tolerability, suggesting that this agent should be used as a first-line agent for APN. Data from our investigation emphasize the importance of visual functional outcome evaluations in clinical trials for APN.