Epidemiology of patients undergoing strabismus surgery at adult age: Retrospective study of 221 patients

Abstract Purpose The strabismus in adult patients could be either the persistence of misalignment since the infancy before the age of visual maturation, or as a consequence of neurological, traumatic or orbital pathology. The aim of this study is to characterize the patients population undergoing strabismus surgery at adult age. Methods In this retrospective and monocentric study were reviewed 221 patients aged of 18 years and above ; the time frame was 3 years. For each patient we analyzed different parameters : age, sex, the treated deviation, the performed surgery, the etiology of the deviation and the presence of diplopia or amblyopia. Results Our patients, aged of 18 to 82 years, reported an onset of strabismus during childhood in 62% (50% with no previous surgical treatment, 20% with a recurrence of already treated strabismus and 30% with a consecutive deviation); 75% of them suffered of amblyopia. The cause of strabismus in 32% of our patients was a secondary deviation due to cranial nerve palsy (55%), traumatism (30%) or orbital pathology (20%). Exotropia was more frequent in our population than esotropia (40% versus 30%). Diplopia was reported in 12% of the patients. The surgery was performed on one eye in 90% and the most frequent operation was on horizontal rectus muscles (64%). Conclusion Adult patients are most frequently suffering of infancy strabismus. When the strabismus onsets at adult age, the most common causes were paralytic strabismus followed by traumatic strabismus. Exotropia was the most prevalent deviation. Surgery could be a simple monocular intervention on rectus muscles or more complex in some cases. The adult patients undergoing strabismus surgery represent a heterogeneous population.