No abstract

A rare case of retrobulbar optic neuropathy caused by an isolated mucocele in an Onodi cell is presented. A 63-year-old man suffering from left recurrent optic neuropathy had shown improved visual acuity with steroid treatment at the age of 48 and 56 years. Impaired visual acuity and blurred vision in the left eye appeared again, and a marked inferior decrease in the left visual field was noted. Although axial computed tomography (CT) showed no abnormal findings, magnetic resonance imaging (MRI) revealed a small squamous-shaped lesion (17 × 17 × 7.3 mm) in the left posterior ethmoidal air cell (Onodi cell) hanging over the left optic nerve. Endoscopic sinus surgery was performed. The optic canal was extruding into the Onodi cell cavity, and the superior bony wall of the canal was eroded by the mucocele. The isolated mucocele in the Onodi cell seemed to be compressing the optic nerve downward and causing retrobulbar optic neuropathy. An Onodi cell lesion, even if it was isolated and small, would cause optic neuropathy. MRI and coronal CT scanning should be performed for the diagnosis and preoperative planning in a case of retrobulbar optic neuropathy.

No abstract

A case of orbital blowout fracture accompanied by fibrosis of the inferior rectus muscle resulting in an irreversible orbital mobility deficit is reported. An 8-year-old girl with an orbital blowout fracture was treated with steroids for 10 days, as with other cases in our department. She exhibited a disturbance of vertical eye movement and a positive forced duction test result. Although surgery was performed on day 13, and on day 27 due to poor recovery after the first operation, almost no improvement of the ocular movement was noted. The results of a traction test, performed during the second operation, suggested that the inferior rectus muscle had adhered to the periosteum. Magnetic resonance imaging performed 3 days after the second operation revealed fibrosis of the inferior rectus muscle and perimuscular tissue, resulting in an irreversible disturbance of the vertical ocular movement. The present findings suggest that the need for and timing of surgery in patients with blowout fractures should be determined on an individual basis.

No abstract