Malignant Solitary Fibrous Tumor of the Orbit

PURPOSE: Solitary fibrous tumor (SFT) is a rare tumor of the pleura, mediastinum, pericardium and other organs affecting predominantly middle-aged patients. SFT arising in the orbit is extremely rare, and its malignant form is even rarer. The authors herein describe a case of malignant solitary fibrous tumor of the orbit. CASE SUMMARY: A 67-year-old male presented with a 4-month history of right proptosis. On ophthalmologic examination, 9-mm proptosis was observed in the right eye, and extraocular movements were limited in all directions of gaze. CT scan and MR imaging showed a lobulated, well-enhancing mass adjacent to the lateral rectus muscle in the superolateral retrobulbar space. Excisional biopsy through a lateral orbitotomy was performed. Histopathological examination showed proliferation of spindle cells with a fascicular pattern interspersed with bands of collagen, increased cellularity, cellular pleomorphism, hemorrhage, necrosis and high mitotic activity. Immunohistochemical staining revealed diffuse positivity for CD34, CD99, Ki67 and p53, and malignant SFT was diagnosed. CONCLUSIONS: Malignant SFT should be considered in the differential diagnosis of acutely progressing unilateral proptosis.

Tissue Incarceration after Ahmed Valve Implantation

PURPOSE: To report cases of intraocular pressure that was normalized, after removing the capsule that had incarcerated into the valve after Ahmed valve implantation. CASE SUMMARY: A 34-month-old boy visited our clinic for elevated intraocular pressure of the right eye. The patient had received Ahmed valve implantation 1 year earlier. At the first ophthalmological examination in our hospital, intraocular pressure of the right eye measured by Perkins tonometer was 28 mm Hg using Cosopt(R) and Iopidine(R), and 26 mm Hg after additional digital massage; the authors decided to remove the capsule with surgery. The fibrotic tissue was removed after finding the tissue incarcerated into the valve during the operation. One day after the surgery, without using any glaucoma medication, intraocular pressure of the right eye measured by Perkins tonometer was 15 mm Hg. Three months after surgery, using topical intraocular pressure lowering agents, intraocular pressure of the right eye was 18 mm Hg. Because the intraocular pressure of other patients after Ahmed valve implantation was not regulated well, surgery was performed, and the fibrotic tissue was removed after finding the tissue incarcerated in the valve during the operation.