"" Imaging of Cranial Nerves

Research Article

Austin J Anat. 2015; 2(3): 1038.

Imaging of Cranial Nerves

Tanrikulu L¹*, Hastreiter P¹, Buchfelder M¹, Jablawi F² and Naraghi R¹

¹Department of Neurosurgery, University of Erlangen- Nuremberg, Germany

²Department of Neurosurgery, RWTH Aachen University, Germany

*Corresponding author: Tanrikulu L, Department of Neurosurgery, RWTH Aachen University, Pauwelsstr, 30, Germany

Received: July 05, 2015; Accepted: September 29, 2015; Published: October 10, 2015

Abstract

Objective: In this study we present our experience in imaging and image processing of cranial nerve anatomy of the cranial nerves V-XI.

Material and Methods: We show the technique of imaging and image processing by high-resolution magnetic resonance imaging and threedimensional (3D) visualization by direct volume rendering. The cranial nerve anatomy is visualized referring the nerval root exit/entry zone, anatomical course within the cisterns of the posterior cranial fossa and the corresponding vasculature. Patients with trigeminal neuralgia, hemi facial spasm and gloss pharyngeal neuralgia were studied.

Results: With highly-resolute MR imaging and 3D visualization by direct volume rendering the anatomy of the cranial nerves V,VI,VII,VIII, IX,X and XI were delineated non-invasively in the pre- and intra operative setup of the surgical domain. There were no disturbances in anatomical visualization.

Conclusion: Cranial nerve imaging by highly resoluted MR imaging and 3D visualization by direct volume rendering gives the opportunity for non-invasive anatomical analysis of cranial nerve topography and corresponding vasculature and brainstem. This contributes for diagnostic and therapeutic decisions and for surgical-anatomical teaching.

Keywords: Cranial nerves; Imaging; Image processing; Neuroanatomy

Abbreviations

2D: two-Dimensional; 3D: three-Dimensional

Introduction

Cranial nerve anatomy and corresponding vasculature still remains as a challenging field for surgeons. There is a need for non-invasive anatomical visualization of the complex 3D topographical details of the cranial nerves and corresponding vessels especially in patients with trigeminal neuralgia, hemi facial spasm, glossopharyngeal neuralgia and for patients with tumors within the posterior cranial fossa such as acoustic neuromas, meningiomas or metastases. The goal of this article is to show our experience in imaging of cranial nerve anatomy and corresponding vessels. The question is whether we are able to transfer given two-Dimensional (2D) anatomical data into more interesting three-Dimensional (3D) delineations in order to get maximum anatomical information about the individual cranial nerve anatomy prior to surgery and at the intra operative surgical domain.

Material and Methods

From the years 2003 until 2006 we routinely examined and treated patients with cranial nerve rhizopathies such as trigeminal neuralgia (41 patients), hemi facial spasm (25 patients) and glossopharyngeal neuralgia (2 patients) [1-3]. All patients underwent high-resolution 1.5 Tesla magnetic resonance imaging described as constructive interference in the steady state (MRI-CISS, Figure 1) [4,5]. In MRICISS sequences the cisterns filled with Cerebro Spinal Fluid (CSF) are depicted with highest intensity and the containing anatomical structures such as the interesting cranial nerves and corresponding vessels are delineated hypo intensely (Figure 1). Therefore the individual three-dimensional anatomy of cranial nerves, vessels and the brainstem is visualized in each patient non-invasively and the position of the anatomical structures can be varied into all directions. The MRI-CISS sequences undergo segmentation (Figure 2) and subsequent 3D visualization by direct volume rendering (Figure 3) [4]. The result is a 3D object represent in the real, individual patient anatomy with topographical details of cranial nerves and surrounding structures as the brainstem and vessels (Figure 4). Our patients underwent micro vascular decompression after sub occipital, retrosigmoidal craniotomy as described by Jannetta [6].