57-year-old woman with squamous cell carcinoma of the left ethmoid sinus, orbit and anterior skull base. Prior to consideration of radiosurgery, the original treatment plan was craniofacial resection with left orbital exenteration. She was treated with 3000 cGy in 5 stages. (A) Coronal CT with contrast prior to radiosurgery with treatment-planning contour. The tumor is shaded in red. Note proximity of left optic nerve. White arrow: optic nerve. (B) Coronal MRI with contrast 13 months after radiosurgery showing dramatic response. Currently, the patient continues to have normal binocular vision nearly 4 years after treatment.