Slit-lamp examination showed diffuse, predominantly central corneal edema with Descemet membrane folds (DMFs), without epithelial defect or infiltrate; posterior segment examination was unremarkable, raising concern for amantadine-related corneal toxicity [1,2,3,4]. A Slit lamp photograph 1 week after discontinuing amantadine, demonstrating predominantly central discoid corneal edema (green circle) with DMFs (arrows). B Slit-lamp photograph at 3-week follow-up after a 1-week amantadine holiday and restart at a reduced dose, due to worsening Parkinson symptoms, showing interval improvement in edema and DMFs with further visual recovery (20/30 OD, 20/25 OS). C and D Pachymetry maps obtained on the same days as (A) and (B), respectively, demonstrating elevated corneal thickness at the earlier time point with subsequent reduction consistent with improving edema.
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Acknowledgements
The authors would like to sincerely thank Robert Ewart for his meticulous processing of all images included in this case and Dr. Daniel Lamoureux for kindly capturing high-quality anterior segment images. They are also deeply grateful to the patient for agreeing to share these findings with the wider medical community.
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KH, SB, and SM contributed equally to all aspects of this case report, including: (1) substantial contributions to the conception and design of the report, (2) drafting the manuscript and critically revising it; and (3) final approval of the version to be published.
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SM reports consultancy fees (Invex Therapeutics); advisory board fees (Ocular Therapeutix, Dompé Farmaceutici); speaker fees (Teva); Travel (AbbVie, EssilorLuxottica and European Alliance of Associations for Rheumatology); Receipt of equipment (Heidelberg Engineering). SM is a member of the Eye editorial board. The other authors declare no potential conflicts of interest.
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Hutchinson, K.A., Baxter, S. & Mollan, S. Drug-induced corneal oedema: amantadine-associated toxicity. Eye (2026). https://doi.org/10.1038/s41433-026-04340-4
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DOI: https://doi.org/10.1038/s41433-026-04340-4
