20150225_nanos_mechanicalcausesofstrabismus1_02

Pathological processes involving the extraocular muscles are some of the most common causes of acquired, nonneurologic strabismus. Although thyroid eye disease is most frequently encountered, other infiltrative, metastatic, and myotoxic processes must be considered. In general, the pathologic processes involving the eye muscles that will be discussed herein (Table) present with a restrictive strabismus that can involve any of the six extraocular muscles. Common presenting signs and symptoms as well as clinical tests can be helpful to the clinician in distinguishing extraocular muscle disease from neurologic causes of strabismus.