title: High-resolution anatomic, diffusion tensor, and magnetization transfer magnetic resonance imaging of the optic chiasm at 3T.
abstract: OBJECTIVE
  To evaluate techniques for anatomical and physiological imaging of the intracranial optic nerve (ON), optic chiasm (OC), and optic tract (OT) at 3T with the aim of visualizing axonal damage in multiple sclerosis (MS).
  
  
  METHODS
  Imaging was performed on a 3T scanner employing a custom-designed head coil that consisted of a coil array with four coils (30 x 30 cm(2)). Oblique fast spin echo (FSE) images, magnetization transfer (MT)-enhanced 3D gradient-echo (GRE) time-of-flight (TOF) images, and line scan diffusion images (LSDI) were obtained. Full diffusion tensor (DT) analysis was performed, and apparent diffusion coefficient (ADC), fractional anisotropy (FA), and fiber direction maps were obtained.
  
  
  RESULTS
  FSE anatomic images were obtained with an in-plane resolution of 0.39 x 0.52 mm(2). The in-plane resolution of the MT and LSDI images was 0.78 x 0.78 mm(2). The OC, intracranial ON, and OT can be seen on these images. The dominant fiber orientations in the OC, ON, and OT, as derived from the DT images, are displayed.
  
  
  CONCLUSIONS
  This study shows that by using 3T and a custom-designed, four-channel head coil, it is possible to acquire high-resolution anatomical and physiological images of the OC, ON, and OT. The pilot results presented here pave the way for imaging the anterior visual pathway in patients with MS.
authors: Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
authors: Elena
authors: E
authors: Vinogradov
authors: Alexandra
authors: A
authors: Degenhardt
authors: Derek
authors: D
authors: Smith
authors: Robert
authors: R
authors: Marquis
authors: Timothy K
authors: TK
authors: Vartanian
authors: Philip
authors: P
authors: Kinkel
authors: Stephan E
authors: SE
authors: Maier
authors: David B
authors: DB
authors: Hackney
authors: Robert E
authors: RE
authors: Lenkinski
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003389:Cranial Nerve Diseases / Q000175:diagnosis* / Q000209:etiology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications / Q000175:diagnosis; D009897:Optic Chiasm / Q000033:anatomy & histology / Q000473:pathology*; D009900:Optic Nerve / Q000033:anatomy & histology / Q000473:pathology*; D010865:Pilot Projects; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity