Inferior alveolar nerve hemangioma

The Laryngoscope C 2016 The American Laryngological, V Rhinological and Otological Society, Inc. Case Report Inferior Alveolar Nerve Hemangioma Reza Vaezeafshar, MD; Stanley Y. Liu, MD, DDS; Douglas Sidell, MD A 14-year-old male presented with lower lip numbness and a slowly enlarging mandibular mass. Computed tomography demonstrated an expansile lesion centered in the marrow space of the left mandibular body, extending along the course of the inferior alveolar nerve (IAN), and expanding the mental foramen. Preoperative diagnosis was consistent with an IAN schwannoma. Surgical planning was performed using PROPLAN CMF software. The lesion was approached via a sagittal split osteotomy and excised en bloc with the IAN. Final pathology demonstrated a capillary hemangioma originating from the inferior alveolar nerve. Based on a detailed PubMed search, this is the first capillary hemangioma of the inferior alveolar nerve reported in the literature. Key Words: Hemangioma, mandible, peripheral nerve tumor, inferior alveolar nerve. Level of Evidence: NA Laryngoscope, 00:000–000, 2016 INTRODUCTION Cranial nerve hemangiomas are exceedingly rare, and usually arise from small vessels surrounding nerves. The optic and facial nerves are the most common cranial nerves involved,1 followed in frequency by oculomotor, vestibulocochlear, and trigeminal nerves.2 To date, reported vascular lesions arising from the trigeminal nerve originate adjacent to the trigeminal ganglion, and often present as a mass arising within Meckel cave.3–5 Of mention, mandibular intraosseous hemangiomas, otherwise known as central hemangiomas, are uncommon but well-described neoplasms that present as a mandibular mass in the second decade of life. These lesions represent a different entity from the neural hemangiomas described in this report, and are distinguishable both by imaging and histologic characteristics.6 Herein, we report a pediatric patient with a capillary hemangioma of the IAN presenting as an expansile mandibular mass. To the best of our knowledge, and after a thorough review of the English literature, this may be the first such lesion described. CASE REPORT An otherwise healthy 14-year-old male with no other medical history was referred to our clinic with an 8-month history of a progressively enlarging left mandibular mass. From the Department of Otolaryngology–Head and Neck Surgery, Stanford Hospital and Clinics, Stanford, California, U.S.A. Editor’s Note: This Manuscript was accepted for publication December 17, 2015. The authors have no funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Douglas Sidell, MD, Department of Otolaryngology–Head and Neck Surgery, 801 Welch Road, Stanford, CA 94304. E-mail: dsidell@stanford.edu DOI: 10.1002/lary.25869 Laryngoscope 00: Month 2016 He initially presented with a 3-week period of isolated left lower lip numbness that was followed by tender left mandibular enlargement. He was treated unsuccessfully with oral antibiotics prior to referral. Computed tomography (CT) demonstrated an enlarged left mental foramen with a 1-cm area of ill-defined increased density within the left mandibular body. The entire extent of the posterior involvement of the lesion was not captured radiologically. Due to enlargement of the foramen and expansion of the inferior alveolar canal, a working diagnosis of IAN schwannoma was established. Upon presentation to our clinic, his mandibular tenderness and swelling had subsided. Examination was significant for persistent anesthesia of the mandibular division of the trigeminal nerve (V3) and slight palpable irregularity of the left mandibular body. Fine-cut CT of the mandible in 0.625-mm slices demonstrated an expansile 3.0 3 1.0-cm lesion centered in the marrow space of the left mandibular body extending along the inferior alveolar nerve course. Expansion of the mental foramen due to erosion of the surrounding cortical bone was again appreciated. These findings favored a peripheral nerve sheath tumor (Fig. 1). To avoid the loss of bone in removal of this lesion for an otherwise healthy child with a presumed benign lesion, we elected to approach it with a sagittal split ramus osteotomy. Preoperative virtual surgical planning was performed using PROPLAN CMF Planning Software (Materialise, Leuven, Belgium) (Fig. 2). The patient was taken to the operating room, and intraosseous-screw retained arch bars were placed using monocortical screws (6 mm in length) into the alveolar bone. The sagittal connecting osteotomy was made with a reciprocating saw from the anterior ramus above the lingula toward the mesial end of the second premolar. Sagittal split was completed with osteotomies in sequential manner. The inferior alveolar nerve trunk with the tumor toward the proximal end was identified. Vaezeafshar et al.: Inferior Alveolar Nerve Hemangioma 1 Fig. 1. (A) Axial computed tomography (CT) of the face demonstrating an expansile lesion centered in the marrow space of the left mandible with expansion of the mental foramen. (B) Coronal CT of the face demonstrating the mass extends along the course of the inferior alveolar nerve. Normal inferior alveolar nerve is shown (arrow) on the right side. The bone marrow surrounding the inferior alveolar nerve had either been resorbed or appeared spongy. Multiple portions of marrow were sent for pathology. There was no evidence of cortical perforation. During the sagittal split approach, an impacted left mandibular third molar was identified and was removed to prevent future infection. The exposure was such that normal but inflamed nerve was identifiable posterior to the lesion within the alveolar canal. The lesion in question was grossly abnormal in appearance, and was inseparable from the nerve itself (Fig. 3). The mass was dissected posteriorly and freed from surrounding bone. The nerve was transected adjacent to the ramus in a normal-appearing region, and submitted as left inferior alveolar nerve tumor (Fig. 4). Remaining abnormal bone and marrow were removed from the space surrounding the lesion. The patient was then placed in intermaxillary fixation using 24-gauge wires. The left mandibular proximal segment was seated in a posterosuperior direction using a pushback instrument. Bicortical screws were placed Fig. 2. PROPLAN CMF planning software (Materialise, Leuven, Belgium) was used for perioperative surgical planning. [Color figure can be viewed in the online issue, which is available at www.laryngoscope.com.] Laryngoscope 00: Month 2016 2 posterior to the last molar tooth via transfacial access. A mandibular fracture plate was then placed at the anterior osteotomy across the inferior border. Due to the resorption of the bony marrow space, demineralized bone matrix was packed within the mandibular cortex. MMF wires were replaced with elastics after confirming appropriate mandibular mobility and occlusion. The patient was discharged on postoperative day 3 in stable condition and maintained in guiding elastics for 1 month. His diet was advanced to a regular diet during the follow-up period, and the intraosseous arch bars were removed 10 weeks after the surgery. His occlusion was stable and reproducible. Final pathology demonstrated a vascular proliferation predominantly composed of capillarysized vessels lined by cytologically bland endothelial cells. Immunohistochemical staining showed that lesional cells were positive for CD34. S100 highlighted the nerve, but was negative for invasion. Findings were consistent with inferior alveolar nerve capillary hemangioma. Fig. 3. Intraoperative photo of the sagittal split ramus osteotomy approach. The inferior alveolar nerve is surrounded with tumor. Exposure is such that the nerve can be traced anteriorly and posteriorly. [Color figure can be viewed in the online issue, which is available at www.laryngoscope.com.] Vaezeafshar et al.: Inferior Alveolar Nerve Hemangioma Fig. 4. Intraoperative photo of the inferior alveolar nerve tumor. The nerve is transected anteriorly 1 cm anterior to the grossly abnormal segment of the nerve. [Color figure can be viewed in the online issue, which is available at www.laryngoscope.com.] DISCUSSION Tumors involving the mandible are uncommon in children. The majority of mandibular lesions in the pediatric population are benign, but a small number are malignant. Benign lesions are classified as primary bone disease, odontogenic lesions, and primary soft tissue processes involving bone of the mandible. The most common mandibular lesions are dentigerous/follicular cysts (16%) and simple (unicameral) bone cysts (13%).7 Regardless of etiology, the most common presenting symptoms of all mandibular lesions are swelling or a mass lesion in the region of the mandible followed by pain, ulceration, and evidence of nerve involvement.7 Vascular lesions of the mandible consist 3.5% of mandibular tumors. The literature is rich in case reports of intraosseous hemangioma, although many of these cases actually represent venous or capillary malformations.8 In the case presented here, the hemangioma originated from the inferior alveolar nerve and was independent of the surrounding mandible. As a result, this lesion is best classified as a tumor of the trigeminal nerve rather than a primary mandibular tumor, thus making the case unique. It is generally accepted by most classification systems that there are three types of primary tumors of the trigeminal nerve: 1) postganglionic root tumors, 2)trigeminal ganglion tumors, and 3) tumors of the peripheral branches.9 The terminal branches of the V1, V2, and V3 are the supraorbital, infraorbital, and inferior alveolar nerves, respectively. Malignancy often involves peripheral branches by virtue of perineural spread, and primarily involves the maxillary division of the nerve.10 Schwannoma is the most common primary neoplasm to involve the trigeminal nerve. This frequently affects the cisternal segment and trigeminal ganglion, although it may occur within any segment of the nerve; the ophthalmic branch being the most common peripheral branch Laryngoscope 00: Month 2016 affected. Vascular neoplasms of the trigeminal nerve are rarely reported in the literature, all originating from the intracranial segment of the nerve.3–5 To our knowledge, this is the first report of hemangioma involving the terminal branch of the mandibular nerve. A final consideration worth mentioning in this report includes our decision to approach this lesion using a technically challenging but tissue-sparing technique. Classically, a benign lesion in this area may be accessed via aggressive buccal window osteotomy, or if further posterior, a midline mandibulotomy. To avoid the loss of bone in this otherwise healthy and growing boy, we opted a sagittal split ramus osteotomy approach. Historic difficulties attributed to this approach include the appropriate positioning of osteotomy sites so as to reduce the risk involving the neoplasm or injury to the IAN. Prior to this operation, we found our CT-based surgical planning software to be of great utility in reducing these risks. Our decision to resect the IAN was based on its obvious tumor involvement as determined intraoperatively. Appropriately placed osteotomies were of great importance. Furthermore, after fixation of the mandibular fragments, there was no continuity with full preservation of mandibular cortical bone. CONCLUSION Trigeminal nerve hemangiomas are very rare tumors that most commonly involve intracranial nerve segments, but can also originate from terminal braches of cranial nerves. In this setting, they may present as a mandibular mass with surrounding bony erosion. Peripheral nerve tumors, such as schwannomas, are among the more common lesions on the differential diagnosis. In the pediatric population, preoperative surgical planning software used in conjunction with mandible-sparing approaches such as the sagittal split ramus osteotomy can preserve healthy surrounding tissues. BIBLIOGRAPHY 1. Redondo P. Vascular malformations concept, classification, pathogenesis and clinical features. Actas Dermosifiliogr 2007;98:141–158. 2. Manjila S, Moon K, Weiner MA, et al. Cavernous malformation of the trochlear nerve: case report and review of the literature on cranial nerve cavernomas. Neurosurgery 2011;69:E230–E238. 3. Saliba I, El Fata F, Berthelet F, et al. Trigeminal nerve haemangioma eroding the petrous carotid canal. J Laryngol Otol 2009;123:1258–1261. 4. Brazis PW, Wharen RE, Czervionke LF, et al. Hemangioma of the mandibular branch of the trigeminal nerve in the Meckel cave presenting with facial pain and sixth nerve palsy. Neuroophthalmol 2000;20:14–16. 5. Fehlings MG, Tucker WS. Cavernous hemangioma of Meckel’s cave. Case report. J Neurosurg 1988;68:645–647. 6. Gomez Oliveira G, Garcıa-Rozado A, Luaces Rey R. Intraosseous mandibular hemangioma. A case report and review of the literature. Med Oral Patol Oral Cir Bucal 2008;13:E496–E498. 7. Benoit MM, Vargas SO, Bhattacharyya N, et al. The presentation and management of mandibular tumors in the pediatric population. Laryngoscope 2013;123:2035–2042. 8. Kadlub N, Dainese L, Coulomb-L’Hermine A, et al. Intraosseous haemangioma: semantic and medical confusion. Int J Oral Maxillofac Surg 2015;44:718–724. 9. Nenashev EA, Kadasheva AB. Tumors of the branches of the trigeminal nerve with extracranial spread. Zh Vopr Neirokhir Im N Burdenko 2013;77:65–71. 10. Borges A, Casselman J. Imaging the trigeminal nerve. J Eur J Radiol 2010;74:323–340. Vaezeafshar et al.: Inferior Alveolar Nerve Hemangioma 3