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Updated: Feb 16, 2026

Induction of Paralysis and Visual System Injury in Mice by T Cells Specific for Neuromyelitis Optica Autoantigen Aquaporin-4
Published on: August 21, 2017
Convergence spasm due to aquaporin-positive neuromyelitis optica spectrum disorder
Pınar Özçelik1, Tural Tanriverdizade2, Süleyman Men3
1Dokuz Eylül University Hospital, Neurology Department.
Abstract:
A female 27 presented with nausea and diplopia for 1 week. On examination she had normal vertical gaze but would develop convergence with miosis whenever she made horizontal saccades. Pupils were 6 mm and unreactive to light. MRI showed extensive hyperintensity in the dorsal midbrain and thalamus. Spinal MRI and CSF were both normal. Serum aquaporin-4-antibody was positive. She was treated with steroids and plasmapheresis and after 3 months convergence spasm resolved but pupils remained unreactive. Neuromyelitis optica often presents with brainstem signs, rarely a dorsal midbrain syndrome. Convergence spasm is occasionally of organic neurologic origin.
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