From the American Academy of Ophthalmology

Investigators used magnetic resonance imaging to evaluate rectus extraocular muscles (EOMS), pulleys, and the lateral rectus (LR) – superior rectus (SR) band ligament in patients with acquired diplopia suspected of having sagging eye syndrome.  Widespread rectus pulley displacement and EOM elongation, associated with LR-SR band rupture, causes acquired vertical and horizontal strabismus. Small-angle esotropia or hypertropia may result from common involutional changes in EOMs and orbital connective tissues that may be suspected from features evident on external examination. JAMA Ophthalmology, May 2013