Fluctuating oculomotor signs in Arnold-Chiari malformation Diagnostic pitfalls

Abstract

Arnold-Chiari malformation can present with internuclear ophthalmoplegia, sixth nerve paralysis, and transient or variable wave-form nystagmus. The differential diagnosis of a fluctuating ocular deviation should include Arnold-Chiari malformation as well as myasthenia gravis and multiple sclerosis. Downward displacement of the cerebellum can even simulate cerebellar atrophy on computed tomography. The presence of skeletal, lower motor neuron, and lower bulbar signs may alert the clinician. Once the etiology is suspected, magnetic resonance imaging (to include the foramen magnum) will determine the diagnosis. Clinical management should be individually tailored. In our experience, one patient required foramen magnum decompression. A recession resection with adjustable sutures was performed in two patients.