A 26-year-old man was admitted for recurrent headaches, loss of vision in his left eye, and elevated blood pressure. His loss of sight had been gradual, manifesting for over six months before hospitalization. He also exhibited episodes of inadequate behavior with some aggression. The patient was conscious at admission, and no other meningeal or focal neurological symptoms were found. The patient consented to publication of his protected health information.\nHis right and left eyes had logarithm of the minimum angle of resolution visual acuities of 1.0 and 0.2, respectively. T1-weighted magnetic resonance imaging (MRI) showed a hyperintense signal mass lesion occupying his chiasm and left ON (Figure ). These findings led to a diagnosis of high-grade glioma of the chiasm and left ON, or CM.\nSurgery was performed with the patient in the supine position, with his head slightly elevated and turned to the right side about 30 degrees. A left frontolateral craniotomy was performed to optimize the approach to the chiasm and left ON. Fenestration of the basal cistern and aspiration of cerebrospinal fluid yielded a relaxed brain with satisfactory gravity retraction. The left optic canal was unroofed, and several blood clots at different stages of resorption were evacuated through the longitudinal dissection of the ON. Minimal coagulation currents were applied to occlude the feeding vessels with their sharp sections. Resection was estimated to be gross total (Video ).\nThere were no surgical complications, and MRI performed six months later showed no signs of CM recurrence (Figure ). The patient was discharged after seven days, and his vision returned to normal three months later. He is still in touch with us and has reported no signs of visual deterioration or recurrent bleeding.\nThe microscopic structure of the resected CM with heterochromous thromboses is shown in Figure .
A 16-year-old boy presented progressive visual disturbance that started 5 months prior with headache. The headache had subsided; however, the visual symptoms persisted. His visual acuity was 0.02 in his left eye and 0.3 in his right eye. The Goldmann perimetry field test revealed a large central scotoma of his left eye field and a temporal hemianopsia of his right eye field (). Brain MR imaging showed a heterogeneous hemorrhagic mass in the optic chiasm, extending posteriorly along the bilateral optic tracts with no definitive contrast enhancement (). The presumptive diagnosis was an unusual CM involving the optic pathway. Following left pterional craniotomy and sylvian dissection, the optic chiasm, which was mottled with dark dots, was visualized. A small window was made on the lateral side of the optic chiasm. Chocolate-colored tissue mixed with old blood was partially evacuated (). The pathology report confirmed the diagnosis of CM. Following surgery, the patient's visual acuity in his left eye slightly improved (0.03/0.3). The central scotoma of his left eye field had resolved; however, he subsequently acquired a nasal hemianopsia in his left eye field. At the patient's 2-year follow-up, there were no episodes of headache, visual change, or documented bleeding on serial MR imaging ().