Objectives. Clinical records of 27 patients with extracranial head and neck schwannoma were retrospectively reviewed. Methods. Ultrasonography (US) was performed in all cases. Seven patients underwent CT. Twenty-five patients underwent MRI. Fine needle aspiration cytology (FNAC) was performed for 12 of the 27 patients. Clinical history, surgical data, and postoperative morbidity were analyzed. Results. The images of US showed a well-defined, hypoechoic, primarily homogeneous solid mass. At CT, only one of 7 cases (14%) was able to suggest the diagnosis of schwannoma. At MRI, twenty of 25 cases (80%) suggested the diagnosis of schwannoma. Only three of 12 cases (25%) displayed a specific diagnosis of schwannoma rendered on FNAC. The distribution of 27 nerves of origin was 10 (37%) vagus nerves, 6 (22%) sympathetic trunks, 5 (19%) cervical plexuses, 3 (11%) brachial plexuses, 2 (7%) hypoglossal nerves, and 1 (4%) accessory nerve. Complete tumor resection was performed in 11 patients, and intracapsular enucleation of the tumor was performed in 16 patients. The rate of nerve palsy was 100 (11/11) and 31% (5/16). Conclusions. MRI is sensitive and specific in the diagnosis of schwannoma. Intracapsular enucleation was an effective and feasible method for preserving the neurological functions. 1. Introduction Schwannoma is a benign neural sheath tumor, and it occurs in overall body areas including the head and neck region. As a slowly growing benign tumor, it has been reported that 25 to 45% of schwannomas were located in the extracranial head and neck region [1]. It involves the cranial nerves such as V, VII, X, XI, and XII or sympathetic and peripheral nerves [2]. Preoperative diagnostic investigations included ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), and fine needle aspiration cytology (FNAC) [3–5]. However, the preoperative diagnosis of schwannoma is difficult and should be suggested by clinical features and supported by investigations. As for the management of schwannomas, multiple treatment options exist including observation, complete tumor excision, and intracapsular enucleation [6, 7]. For tumors arising from the major cranial nerves, complete tumor resection renders lifelong morbidity to the patients. On the other hand, the nerve-preserving excision method, such as intracapsular enucleation, does not guarantee intact nerve function after surgery. Because of the substantial chance of nerve palsy after operation, obtaining an accurate preoperative diagnosis, and preferably, with the identification of the nerve of
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