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Updated: Jul 26, 2026

A High-throughput-compatible FRET-based Platform for Identification and Characterization of Botulinum Neurotoxin Light Chain Modulators
Published on: December 27, 2013
[Spasm of the near reflex. Treatment with botulinum toxin]
P Merino1, P Rojas1, P Gómez de Liaño1
1Sección de Motilidad Ocular, Departamento de Oftalmología, Hospital Gregorio Marañon, Madrid, España.
Clinical Case:
A 38-year old female with diplopia and esotropia, with limitation of ocular abduction in both eyes, with full abduction after doll's head rotation also being observed. She was diagnosed with spasm of the near reflex. Treatment with injections of botulinum toxin in both medial rectus has temporally resolved the convergence spasm.
Discussion:
Near reflex spasm is characterized as miosis, pseudomyopia, and convergent strabismus that lead to diplopia, blurred vision, headache, and variable, progressive, and intermittent esotropia. As the spasm worsens there will be limited ocular versions and ductions simulating a sixth nerve palsy. Botulinum toxin may be effective in some cases.
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Botulism

