Image Article
Hypoglossal Neurinoma of The Carotid Space Segment
Natalia Rotaru, MD, PhD, Maxim Crivcheanschii, MD, Janna Punga, MD, PhD, Eugeniu Condrea, MD, and Ion Codreanu, MD, PhD*
Corresponding Author: Ion Codreanu, M.D., Ph.D., Department of Radiology and Medical Imaging , State University of Medicine and Pharmacy “Nicolae Testemitanu”, Chisinau, MD 2025 Republic of Moldova, Phone: (373) 6769 3616, E-mail: codrion@yahoo.com.
Received: October 16, 2016; Accepted: October 21, 2016; Published: October 27, 2016;
Citation: Rotaru N, Crivcheanschii M, Punga J, Condrea E & Codreanu I (2016) Hypoglossal Neurinoma of the Carotid Space Segment. Int J Med Clin Imaging, 1(1): 8-9.
Copyrights: ©2016 Rotaru N, Crivcheanschii M, Punga J, Condrea E & Codreanu I. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
 

Keywords: Hypoglossal nerve palsy, Neurinoma, MRI.

A 33-year-old female presented with deviation of her tongue towards the right side (Figure 1, A). Magnetic resonance imaging (MRI) of the head revealed a 1.0 x 0.8cm mass abutting the right internal carotid artery in close proximity to the hypoglossal canal. The mass proved relatively isointense to brain parenchyma on T1 weighted images (Figure 1, B), slightly hyperintense on T2 weighted images (Figure 1, C), with a higher signal intensity on T2-tirm imaging (Figure 1, D).  A “T2 shine through” phenomenon was also noted on Diffusion Weighted Imaging (DWI) with Apparent Diffusion Coefficient (ADC) mapping (Figure 1, E and F), the findings being consistent with a hypoglossal neurinoma (schwannoma) of the carotid space segment.


The hypoglossal nerve is divided into five segments: the medullary, cisternal, skull base, carotid space, and sublingual segments. Because each segment is usually affected by different disorders, localizing a lesion to a particular segment allows the physician to narrow the differential diagnosis [1]. Cranial nerve schwannomas are usually isolated lesions, except when they are associated with neurofibromatosis type 2 (abnormality of chromosome 22) [2]. Because of the substantial chance of nerve palsy following resection, obtaining an accurate preoperative diagnosis with the identification of the involved structures is crucial to the management strategy [3]. MRI is the investigation of choice in the diagnosis of schwannoma and the identification of the nerve of origin [3]. Evolving MRI techniques such as super selective diffusion tensor tractography (DTT) can provide further details related to the tumor and cranial nerve interface, including the presence or absence of penetrating fibers [4]. 

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