title: Diffusion tensor imaging for anatomical localization of cranial nerves and cranial nerve nuclei in pontine lesions: initial experiences with 3T-MRI.
abstract: With continuous refinement of neurosurgical techniques and higher resolution in neuroimaging, the management of pontine lesions is constantly improving. Among pontine structures with vital functions that are at risk of being damaged by surgical manipulation, cranial nerves (CN) and cranial nerve nuclei (CNN) such as CN V, VI, and VII are critical. Pre-operative localization of the intrapontine course of CN and CNN should be beneficial for surgical outcomes. Our objective was to accurately localize CN and CNN in patients with intra-axial lesions in the pons using diffusion tensor imaging (DTI) and estimate its input in surgical planning for avoiding unintended loss of their function during surgery. DTI of the pons obtained pre-operatively on a 3Tesla MR scanner was analyzed prospectively for the accurate localization of CN and CNN V, VI and VII in seven patients with intra-axial lesions in the pons. Anatomical sections in the pons were used to estimate abnormalities on color-coded fractional anisotropy maps. Imaging abnormalities were correlated with CN symptoms before and after surgery. The course of CN and the area of CNN were identified using DTI pre- and post-operatively. Clinical associations between post-operative improvements and the corresponding CN area of the pons were demonstrated. Our results suggest that pre- and post-operative DTI allows identification of key anatomical structures in the pons and enables estimation of their involvement by pathology. It may predict clinical outcome and help us to better understand the involvement of the intrinsic anatomy by pathological processes.
authors.affiliation: Department of Neurosurgery, University Hospital, University of Zurich, Zurich, Switzerland; Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland. Electronic address: nils.hb.ulrich@gmail.com.
authors.forename: Nils H
authors.initials: NH
authors.lastname: Ulrich
authors.affiliation: Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland.
authors.forename: Uzeyir
authors.initials: U
authors.lastname: Ahmadli
authors.affiliation: Department of Neurosurgery, University Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: Christoph M
authors.initials: CM
authors.lastname: Woernle
authors.affiliation: Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland.
authors.forename: Yahea A
authors.initials: YA
authors.lastname: Alzarhani
authors.affiliation: International Neuroscience Institute, INI, Hannover, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Bertalanffy
authors.affiliation: Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland.
authors.forename: Spyros S
authors.initials: SS
authors.lastname: Kollias
mesh_terms: D000328:Adult; D059925:Anatomic Landmarks; D020295:Brain Stem Neoplasms / Q000150:complications / Q000601:surgery*; D003389:Cranial Nerve Diseases / Q000209:etiology; D020209:Cranial Nerve Injuries / Q000517:prevention & control; D003391:Cranial Nerves / Q000033:anatomy & histology*; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D020786:Hemangioma, Cavernous, Central Nervous System / Q000150:complications / Q000601:surgery*; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control; D008297:Male; D008866:Microsurgery / Q000379:methods; D008875:Middle Aged; D059906:Neuroimaging / Q000379:methods*; D038361:Neuronavigation / Q000379:methods*; D011149:Pons / Q000601:surgery*; D011446:Prospective Studies; D012189:Retrospective Studies; D055815:Young Adult
keywords: Brainstem; Cavernoma; Cranial nerve; Cranial nerve nuclei; DTI; MRI; Pons