Fibromyxoma of the Orbit.

Fibromyxomas are rare tumors that are not commonly seen in the orbit. The authors present a case of orbital fibromyxoma. A 42-year-old male presented with proptosis of the right eye that began 1 month prior. Magnetic resonance imaging revealed the presence of an orbital mass in the right eye, with low signal intensity on T1-weighted images and heterogeneous high-signal intensity on T2-weighted images. The patient underwent excisional biopsy of the orbital tumor through a Krönlein approach. The tumor originated from the inferior rectus muscle. Histopathologic analysis demonstrated scattered spindle cells, with both fibrous and myxoid stroma. Immunohistochemical staining was positive for Vimentin and negative for S-100 protein and CD34. The tumor was diagnosed as orbital fibromyxoma. The patient showed no evidence of recurrence over 18 months of follow-up after operation.