Central Annals of Otolaryngology and Rhinology Case Report *Corresponding author İbrahim Murat Afat, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Marmara Infraorbital Schwannomas: University, Istanbul, Turkey, Tel: 0090 216 421; Email: Review of the Literature and Submitted: 10 October 2018 Accepted: 07 November 2018 Presentation of a Rare Case Published: 09 November 2018 ISSN: 2379-948X Ibrahim Murat Afat* Copyright © 2018 Afat Department of Oral and Maxillofacial Surgery, Marmara University, Turkey OPEN ACCESS Abstract Keywords Schwannomas are well-differentiated, benign tumours arising from the Schwann cells of the • Schwannoma nerve sheath. Schwannomas arising from the infraorbital nerve (ION) are very rare, and very • Infraorbital nerve few cases are reported in literature. The Review of the Literature covered all English literature between 1944 and January 2018. The keywords used in the search were ‘schwannoma’ or ‘neurinoma’ or ‘neurilemmoma’ and ‘infraorbital’ or ‘infra-orbital’. As a result, 10 cases of ION and branch case reports and 4 cases of malignant peripheral nerve sheath tumours with ION involvement were examined in full text. A rare case of a schwannoma arising from the medial superior labial branch of the ION and its treatment are presented. INTRODUCTION Schwannomas or neurilemmomas are well-differentiated provide data on age, gender, location, presenting symptoms, size, benign tumours arising from the Schwann cells of the nerve andCASE treatment PRESENTATION methods. sheath with well-defined borders [1,2]. A 28-year-old male patient presented with a progressively The first description of this tumor was by Verocay in 1910,the enlarging, painless but tender-to-touch swelling over the right first trigeminal nerve schwannoma was reported by Smith in cheek. Physical examination showed a firm, subcutaneous 1835, who described a tumor of the gasserian ganglion [3]. 3-cm lump in the right infraorbital region that was not fixed to butmost of these originate from the lower cranial nerve and the skin or underlying bone (Figure1a). The nasolabial fold was Schwannomas are common in the head and neck region, shallowed. The skin was pinchable over the lesion. There was no proptosis, and vision was normal. There was no subjective sympathetic nervous system [4]. Schwannomas from the upper sensory deficit as compared with the left side, and cervical lymph cranial nerves, such as the trigeminal nerve and its branches, are nodes were not palpable. There was no significant family history lessThe common. infraorbital nerve (ION) is the continuation of the of other illnesses. There were no other similar lesions in the trunkIntra-oral or limbs. examination showed no swelling over the anterior maxillary nerve after it has entered the orbit, through the infraorbital fissure, traversing the infraorbital canal to reach the maxilla. The maxillary anterior teeth were vital, firm, nontender face innervates the midface maxillary region. Most of the ION on percussion, and had no cavities. territory is supplied by the nasal and superior labial branches, Computed tomography (CT) showed a well-defined expansile which divide within the infraorbital canal. The nasal nerves hypodense lesion arising from the right maxillary region above comprise the external nasal nerve, which terminates in the ala the root of the maxillary anterior teeth. The overall clinical of the nose and the internal nasal nerve, which terminates in presentation was suggestive of a benign subcutaneous lesion, the nasal vestibule. The superior labial nerve has a medial and and the differential diagnosis included fibroma, lipoma, dermoid a lateral sub-branch, which terminates in the superior lip [5]. cyst, epidermoid cyst, and neurogenic tumour (Figure 1b). Schwannomas arising from the ION are very rare, and few cases The magnetic resonance imaging (MRI) scans showed well- are reported in the literature [2]. defined, heterogeneous oval mass of 3,5 × 3,0 × 2,3 cm within the Here we describe a case of a schwannoma of the ION, including buccal sub-cutaneous tissue with no orbital, maxillary sinus or a review of the literature from 1944 to January 2018, and we underlying bone involvement. (Figure 1c, d). Cite this article: Afat IM (2018) Infraorbital Schwannomas: Review of the Literature and Presentation of a Rare Case. Ann Otolaryngol Rhinol 5(4): 1217. Afat (2018) Email: [email protected] Central Surgical excision of the lesion was planned and executed under local anaesthesia. After intraoral vestibular incision at the time of exploration, the lesion was well-encapsulated and was freed from surrounding tissue by blunt dissection. The lesion was found to emanate from the nerve trunk of the peripheral branch of the ION (Figure 2a, b). labial branch of the ION. The mass was excised by sacrificing the involved medial superior Gross examination showed an oval-shaped, well- circumscribed tumour, apparently encapsulated, with a homogeneous surface, which was yellow-gray in color and of medium consistency. Figure 2 Intraoperative view a,b: shows a well-circumscribed, The patient reported paraesthesia localized over the area of encapsulated, pink mass that attached to the infraorbital nerve branch. distribution of the medial superior labial branch of the ION after surgery. Histopathological examination (hematoxylin and eosin staining) of the tan-colored specimen excised revealed a tumour composed of fascicles of monomorphic spindle- eosinophilic cytoplasm (Figure 3a). There was diffuse nuclear immunopositivityshaped cells with topointed S-100 basophilicprotein, indicative nuclei and of apoorly schwannoma defined (Figure 3b). Diagnosis of a schwannoma, arising from the medial superior labial branch of the ION, was established. The patient had an Figure 3 uneventful recovery and continues to be free of recurrence one year after surgery. b: Intense andHistopathological diffuse reactivity findings. with anti-S- a: 100Hematoxylin protein antibody. and eosin staining, original magnification×10, shows dense spindle shaped cells. Review of the Literature Library of Medicine (Medline PubMed). The search covered all The literature searches were performed using the National literature between 1944 to January 2018. Keywords used in the search were ‘schwannoma’ or ‘neurinoma’ or ‘neurilemmoma’ studies or reports in humans. No animal studies were included. and ‘infraorbital’ or ‘infra-orbital’. The search was confined to The search as; (Infra-orbital [All Fields] OR Infraorbital[All Fields]) AND (“neurilemmoma”[All Fields] OR “neurinoma”[All Fields] OR “schwannoma”[All Fields])yielded 29 results and 19 of them related to the subject. As a result, 10 cases of ION and branch case reports [1-4, 6-11] (Table 1), and 4cases of malignant peripheral nerve sheath tumours with ION involvement [12-15] (Table 2) were examined in full text. Five case reports published between 1961-1979 that (Table 3). were not have abstract were identified from their title [16-20] DISCUSSION Head and neck tumours of neurogenic origin are relatively rare and constitute a heterogeneous group of neoplasms with vastly different histologic features, behaviours, and prognoses. A schwannoma is an ectodermal benign neoplasm arising from Schwann cells present in nerve sheaths [4]. These cells are neural crest-derived glial cells, providing myelin insulation to peripheral nervous system axons [21]. Of the 12 cranial nerves, only the olfactory and optic nerves do not develop schwannomas because they lack Schwann cells Figure 1 a: Preoperative photograph of the patient b: Computed in their sheaths. Schwannomas may be intracranial (central tomography scan. c,d: Coronal and Axial view magnetic resonance schwannomas) or located in the soft tissues (peripheral imaging scans of the facial area. schwannomas) [3]. Ann Otolaryngol Rhinol 5(4): 1217 (2018) 2/6 Afat (2018) Email: [email protected] Central Table 1: Summarizes the features of the previously reported infraorbital nerve schwannomas. Author, year of Follow up Dura- Size of Surgical Ap- No. publica- Journal Age Sex Clinical Features Area Involved and Re- tion tumuor proach tion and currence region Paresthesia over the Right infraorbital Endoscopic Cham- region, extended endonasal Clinical 2 months pagnea with chewing. exoph- intracrani- 5.6 x3.1x approach, 1 Neurology and 48 male 6 years no recur- et.al 2014 thalmia,right cheek, upward difficulty gaze ally centeredon 6 cm endoscopic Neurosurgery rence. Canada - pterygopalatine maxillary ocular diplopia. fossa. meatotomy. Paresthesiadeficit and vertical over the bin Pterygopalatine Weber Fergus- Indian Journal of Sasindran right infraorbital re- fossa, extended son incision, 1 months Otolaryngology 6 2 et.al 2008 22 male gion. Diminished vision into infratem- n/a transantral ap- no recur- and Head & Neck months India poral fossa and proach partial rence. Surgery nasal obstruction. maxillectomy. Boneand corneal erosion reflex of the and infraorbital canal and floor of the orbit Clarençon - Journal of fe- - 3 et.al 2009 45 n/a Infraorbital canal n/a ber Fergusson n/a Neuroradiology male lar globe and inferior France incision.Modified We rectusorbital musclefloor. Left were ocu displaced upwards. Kok et.al Right nasolabial 2 years Annals of Plastic Right nasolabial subcu- 3 2.3x 2.1x Sublabial in- 4 2013 Singa- 12 male subcutaneous no recur- Surgery taneous lump months 1.7 cm traoral incision. pore lump rence 3 years Nainaet.al Indian Journal of Painless swelling over 6 Right maxillary Caldwell Luc 5 26 male