{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T07:40:30Z","timestamp":1772264430878,"version":"3.50.1"},"reference-count":14,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2022,8,17]],"date-time":"2022-08-17T00:00:00Z","timestamp":1660694400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurol."],"abstract":"<jats:sec><jats:title>Introduction<\/jats:title><jats:p>Oculopalatal tremor (OPT) is a late manifestation of a Guillain-Mollaret triangle lesion. Memantine has been shown to improve nystagmus in OPT, but its long-term efficacy and putative distinct effects on each plane of nystagmus and on associated phenomena (e.g., gravity perception) are largely unknown.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>We conducted a 6-month open-label study to evaluate the effect of memantine in OPT patients. Baseline (visit 1), 2 (visit 2), and 6 months (visit 3) assessments included video-oculography, best corrected visual acuity (BCVA), visual function questionnaire (VFQ25), palatal tremor frequency, and subjective visual vertical (SVV). Memantine was titrated to 20 mg per day and stopped after 6 months.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>We included six patients (5 females; mean age 68.5+\/-9.7). At visit 2, nystagmus improved &amp;gt;50% only along the horizontal plane in two patients, while worsening &amp;gt;50% along the vertical and horizontal planes in 4 and 1 patients, respectively. At visit 3, previous improvement of nystagmus along the horizontal plane in two patients was not sustained, and it further worsened &amp;gt;50% along the vertical plane in 4. The mean vertical velocity and amplitude of nystagmus in the left eye significantly worsened from visit 2 to visit 3 (<jats:italic>p<\/jats:italic> = 0.028). Throughout the study, nystagmus frequency remained unchanged (<jats:italic>p<\/jats:italic> = 0.074), BCVA improved in both eyes (<jats:italic>p<\/jats:italic> = 0.047, <jats:italic>p<\/jats:italic> = 0.017), SVV progression was unpredictable (<jats:italic>p<\/jats:italic> = 0.513), and the mean VFQ-25 score (<jats:italic>p<\/jats:italic> = 0.223) and mean palatal frequency remained unchanged.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>The long-term use of memantine 20 mg per day in OPT produced a modest and only transient improvement in nystagmus, predominantly along the horizontal plane. Visual acuity improved, albeit without relevant changes in vision-related quality of life.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fneur.2022.921341","type":"journal-article","created":{"date-parts":[[2022,8,17]],"date-time":"2022-08-17T05:14:01Z","timestamp":1660713241000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["A 6-month trial of memantine for nystagmus and associated phenomena in oculopalatal tremor"],"prefix":"10.3389","volume":"13","author":[{"given":"Ana In\u00eas","family":"Martins","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ricardo","family":"Soares-dos-Reis","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andr\u00e9","family":"Jorge","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cristina","family":"Duque","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniela Jardim","family":"Pereira","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carlos","family":"Fontes 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