Solitary Fibrous Tumor of Orbit: Changes of Tumor Size and Tumor Contrast Enhancement

Purpose: To report a case of solitary fibrous tumor of the orbit in a patient with changes in tumor size and contrast enhancement.Case summary: A 64-year-old male patient presented with dizziness, discomfort on eye movement, anosmia, and proptosis. Orbital computed tomography showed an enhancing mass in the right extraconal space, lateral to the medial rectus and inferior to the superior oblique muscle. The mass appeared to be a cavernous hemangioma and the patient was monitored for changes in mass size and eye movements. After 24 months of follow-up, the mass size and symptoms of right eyelid swelling, proptosis, and diplopia had increased. Excision and biopsy of the mass were performed under general anesthesia. The biopsy confirmed that the mass was a solitary fibrous tumor. The postoperative period was uneventful and no recurrence was observed at 6 months after surgery.Conclusions: Solitary fibrous tumor is a soft tissue tumor that rarely occurs in the orbit, and should be considered in cases with an intraorbital mass accompanied by increased size and changes in contrast enhancement on imaging.