Alteration of the early reflex component of the orbicularis oculi reflex was demonstrated in 11 of 12 patients with internuclear ophthalmoplegia. One patient with partial internuclear ophthalmoplegia and eight patients with myasthenic ophthalmoplegia, including two instances of pseudointernuclear ophthalmoplegia, had normal results of orbicularis oculi reflex studies. It is suggested that study of the orbicularis oculi reflex is useful in quantitatively evaluating patients with internuclear ophthalmoplegia and in differentiating internuclear ophthalmoplegia from pseudointernuclear ophthalmoplegia.
Lyon LW, Van Allen MW. Orbicularis Oculi ReflexStudies in Internuclear Ophthalmoplegia and Pseudointernuclear Ophthalmoplegia. Arch Ophthalmol. 1972;87(2):148-154. doi:10.1001/archopht.1972.01000020150006