title: Polytomoencephalography of the optic chiasm and adjacent structures.
abstract: The addition of polytomography considerably increases the sensitivity of pneumoencephalography. The chiasmatic area lends itself particularly well to investigation by polytomoencephalography. In a series of 28 patients, the transverse dimension of the optic chiasm ranged from 4 to 20 mm, with a mean of 18 mm. The posterior portion of the chiasm tended to be U-shaped; its anterior portion's shape was that of a dumbbell. Intrachiasmatic tumors distort and enlarge the chiasm. The diaphragma sella is also particularly well evaluated by this technique. The study is safe, reliable, and can be repeated as needed.
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009897:Optic Chiasm / Q000000981:diagnostic imaging*; D009900:Optic Nerve / Q000000981:diagnostic imaging; D010523:Peripheral Nervous System Diseases / Q000000981:diagnostic imaging; D011011:Pneumoencephalography; D012658:Sella Turcica / Q000000981:diagnostic imaging; D014056:Tomography, X-Ray