7/23/2023 0 Comments Internal auditory canal mriThe inner ear imaging anatomy with 3T MRI new sequences: A comprehensive update ECR 2014 Poster C-2316 - E.Detailed MR imaging anatomy of the cisternal segments of the glossopharyngeal, vagus, and spinal accessory nerves in the posterior fossa: the use of 3D balanced fast-field echo MR imaging. (Neuroradiologist, ENT imaging specialist, Montpellier – France) for her help and medical advice, essential for the creation of this module. The authors would like to thank Sophie Menjot de Champfleur M.D. (Radiologist, Montpellier – France), using the Terminologia Anatomica 2 and the Terminologia Neuroanatomica. The anatomical labeling has been performed by Antoine Micheau M.D. Samuel Merigeaud (Tridilogy - Montpellier, France). The 3D images of the inner ear (cochlea, semicircular canals and vestibule) and the facial and vestibulocochlear nerves were created using the MRI native images on VG Studio Max by the Dr. The images were then cropped to focus on the right temporal bone and cerebellopontine angle. MRI images were post-treated with Horos to obtain MPR reconstructions in two different oblique-sagittal planes (a series perpendicular to the internal auditory canal and a series in the axis of the anterior semicircular canal). (Radiologist, Montpellier – France).įorty four images of the posterior fossa were obtained, with 0.6 mm thickness. This neuroanatomy atlas of cerebellopontine angle and temporal bone has been designed to help radiologists in their daily practice (MRI of vestibular schwannoma, hearing loss, audiovestibular syndromes…) with annotated MR reconstructions in the essential planes (axial and two oblique-sagittal planes), spatial orientation and color-text legend.Ī T2 3D CISS (constructive interference in steady state) sequence of the inner ear has been performed on a healthy 35 year old female patient on a 1.5T Siemens Magnetom Sola by Antoine Micheau M.D. Structures that can be seen are facial and vestibulocochlear nerves.This anatomical module of e-Anatomy is dedicated to the anatomy of the inner ear (cochlea, bony and membranous labyrinth) and the normal MRI appearance of the facial and vestibulocochlear nerves in the internal acoustic meatus on high resolution T2 images of the posterior fossa. The anatomy of the internal auditory canal is best seen on high-resolution T2-weighted image sequences. Narrow duplicated internal acoustic canal 2 From here three bundles emerge: superior and inferior division of the vestibular nerve and the nerve from the posterior semicircular canal (see article: vestibulocochlear nerve (CN VIII) for further details). In addition to the three nerves which enter it, it also contains the vestibular ganglion ( ganglion of Scarpa). See mnemonic for the position of the nerves in the IAC. Inferior: cochlear nerve and inferior vestibular nerve (IVN) the cochlear nerve is situated anteriorly Superior: facial nerve and superior vestibular nerve (SVN) the facial nerve is anterior to the SVN and is separated from it laterally by Bill's bar, a vertical ridge of bone This horizontal ridge divides the canal into superior and inferior portions: Their position is most constant in the lateral portion of the meatus which is anatomically divided by the falciform crest. Superior vestibular nerve (component of CN VIII) Inferior vestibular nerve (component of CN VIII) Nervus intermedius (sensory component of CN VII)įacial motor root (motor component of CN VII) There are five nerves that run through the IAM: Labyrinthine artery (usually a branch of the AICA or basilar artery) The canal narrows laterally, and the lateral boundary is the fundus, where the canal splits into three distinct openings, one of which is the facial nerve canal. The margins of the opening are smooth and rounded, and the canal is short (1 cm), running laterally to the bone. The opening of the IAM, the porus acusticus internus, is located within the cranial cavity, near the posterior surface of the temporal bone.
0 Comments
Leave a Reply. |