To report the prevalence and causes of strabismus in children with eyelid ptosis diagnosed in a well-defined population over a 40-year period.
Retrospective, population-based cohort study.
We retrospectively reviewed the charts of 107 patients (<19 years) for the prevalence and causes of strabismus in children who were diagnosed with childhood eyelid ptosis as residents of Olmsted County, Minnesota, from January 1, 1965, through December 31, 2004.
Strabismus was diagnosed in 20 (18.7%) of the 107 patients with childhood ptosis. Of the 81 patients, 8 (9.9%) were diagnosed with simple congenital ptosis and had strabismus, of which there were 4 (4.9%) cases of exotropia and 4 (4.9%) cases of esotropia. There were no cases of isolated vertical deviation.
Strabismus occurred in 1 of 5 children diagnosed with any form of childhood ptosis in this population-based cohort. Strabismus affected approximately 1 of 10 patients diagnosed with simple congenital ptosis, and a predominance of isolated horizontal deviations was equally divided between esotropia and exotropia.
Strabismus has been reported to occur in 10.3%–32% of patients with childhood ptosis. The purpose of this study was to describe the rate and types of strabismus in a population-based cohort of 107 children diagnosed with ptosis during a 40-year period.
The medical records of all patients younger than 19 years of age with childhood ptosis, while residing in Olmsted County, Minnesota, and diagnosed between January 1, 1965, and December 31, 2004, were retrospectively reviewed after obtaining institutional review board approval. The medical records of 107 patients (81 patients with simple congenital ptosis) met inclusion criteria and were reviewed for the presence of strabismus, defined as an intermittent or constant horizontal deviation of 10 or more prism diopters, a vertical deviation of 2 or more prism diopters, or other eye movement disorders. The incidence and demographics of this population of children with eyelid ptosis and the prevalence of amblyopia have been reported previously.
Of the 107 study patients, 20 (18.7%) were diagnosed with strabismus in Olmsted County, Minnesota, during the 40-year period. Further information concerning the forms of ptosis and strabismus are shown in the Table . There were 11 (55%) females and 9 (45%) males. All cases of strabismus occurred in patients with unilateral ptosis except for 1 patient each with congenital fibrosis of the extraocular muscles, Noonan syndrome, or childhood myasthenia gravis.
|Ptosis Etiology||Number (%)||Strabismus Cases (%)|
|Exotropia||Esotropia||Other Forms of Strabismus|
|Simple congenital ptosis||81 (75.7)||4 (4.9) a||4 (4.9)||0|
|Blepharophimosis||3 (2.8)||1 (33)||0||0|
|Congenital CNIII palsy||3 (2.8)||0||0||3 (100)|
|Marcus Gunn jaw wink||3 (3.8)||0||1 (33)||0|
|Congenital Horner syndrome||2 (1.9)||0||0||0|
|Central core myopathy||1 (0.93)||0||0||0|
|CFEOM||1 (0.93)||0||0||1 (100)|
|Myotonic dystrophy||1 (0.93)||0||0||0|
|Noonan syndrome||1 (0.93)||0||1 (100) b||0|
|Aponeurotic dehiscence||4 (3.7)||0||1 (25)||0|
|Acquired CN III palsy||2 (1.9)||0||0||2 (100)|
|Acquired Horner syndrome||2 (1.9)||0||0||0|
|Traumatic structural ptosis||2 (1.9)||0||0||1 (50)|
|Childhood myasthenia gravis||1 (1.9)||1 (100)||0||0|
|Total||107||6 (5.6)||7 (6.5)||7 (6.5)|