Manifest strabismus following pseudostrabismus diagnosis.

INTRODUCTION Pseudostrabismus is a common diagnosis in a busy pediatric ophthalmology practice. This purpose of this study was to determine the prevalence of true strabismus in patients previously diagnosed with pseudostrabismus, to determine risk factors, and to examine the sensory outcome. METHODS This is a retrospective review of patients diagnosed with pseudo-strabismus and with at least one follow-up visit. Age at first visit, gender, family history, birth weight, developmental history, who initially suspected strabismus and its direction, refractive error, and quality of examination were recorded. Diagnosis and sensory outcome were recorded for those patients who went on to develop a manifest deviation. RESULTS Eighty-three patients met the inclusion criteria. Twelve percent (10/83) were later diagnosed with manifest strabismus. There was no statistically significant difference between those who went on to develop strabismus and those who did not with regard to any of the factors evaluated; however, there was a strong trend for higher risk in developmentally delayed subjects. Additionally, there was a trend for higher risk when poor patient cooperation or an inexperienced clinician precludes a good quality exam. Two subjects developed amblyopia before diagnosis. At the final exam, there was evidence of bifoveal fusion in five subjects and of peripheral fusion in three subjects. CONCLUSIONS The prevalence of strabismus was higher in patients diagnosed with pseudostrabismus than was reported for the general pediatric population. Therefore, patients diagnosed with pseudostrabismus might be considered "at risk". With pseudostrabismus, management should reflect this increased risk of true strabismus. Confirmatory studies are needed.