Giant orbital cyst after strabismus surgery.

We describe the clinical, histopathologic, and radiologic findings and management of a patient who had a giant orbital cyst after reoperative strabismus surgery. In the case report, we describe, in detail, a giant orbital cyst developing on the medial side of the globe after the third operation for repair of strabismus. Imaging studies, including computed tomographic (CT) scan and orbital ultrasound, demonstrate the findings. The observations at surgery and the surgical pathologic condition of the cyst are described. The orbital cyst was successfully removed, advancing the remaining medial rectus muscle and recessing the lateral rectus muscle, which resulted in reduction of a large-angle exotropia to a small exodeviation. Adduction was improved but not normalized. The pathologic examination indicated a benign inclusion cyst of the conjunctiva with fibrosis and chronic inflammation. A possible cause of this type of cyst is an epithelial remnant inadvertently placed with the muscle substance during previous surgery.