Sagging Eye Syndrome and Distance Esotropia in the Elderly

Purpose: Sagging eye syndrome (SES) causes strabismus because orbital connective tissue degeneration allows inferior shift of the lateral rectus (LR) extraocular muscle pulleys. This paper reviews this relatively common, nonneurological cause of diplopia in older adults. Methods: High-resolution MRI of the orbits in patients with SES has been quantitatively compared with normal subjects age-matched to SES, and normal young adults. MRI has defined rectus pulley locations comparable to age-matched norms, and has quantified lengths of the LR-SR band ligament and rectus EOMs. These data have been correlated with facial and adnexal features, and ocular motility. Results of strabismus surgery have been systematically assessed in age-related distance esotropia (ARDE, "divergence paralysis") and cyclovertical strabismus (CVS) due to SES. Results: Patients with SES commonly exhibit blepharoptosis and superior sulcus defect, and are likely to have previously undergone blepharoplasty or facelift surgery. The MRI hallmark of SES is significant inferolateral LR pulley displacement, with peripheral displacement of all other rectus pulleys, and lateral displacement of the inferior rectus pulley. Rectus muscles are generally elongated. Symmetrical LR sag is associated with ARDE, and asymmetrical LR sag >1 mm with CVS in which the hypotropic eye is also excyclotropic. The LR-SR band ligament is ruptured in the great majority of patients with SES. While there is no horizontal duction limitation or saccade slowing, patients typically have limited sursumversion due to medial rectus (MR) and LR sag. ARDE responds well to MR recession with augmented dosing, or to LR resection or plication. CVS may be treated by graded vertical rectus tenotomy or more conventional strabismus surgeries.