Neck Schwannomas Research Articles

内視鏡下に摘出しえた鼻腔神経鞘腫例

Schwannoma is a neurogenic tumor arising in peripheral nerve sheath Schwann cells. Most head and neck schwannomas occur as acoustic neurinomas, with sinonasal involvement accounting for 3%. Complete resection is vital to preventing local recurrence. Extended resection may be difficult however due to paranasal sinus location. We report a case of sinonasal schwannoma resected in endoscopic sinus surgery and discuss the usefulness of and about indications for intranasal schwannoma treatment.

Cystic schwannoma in neck: Fallacious diagnosis arrived on fine needle aspiration cytology

Cystic schwannoma in neck: Fallacious diagnosis arrived on fine needle aspiration cytology

Nonvestibular Schwannomas of the Head and Neck

Alper Ceylan MD, Assoc. Prof. Gazi University Medical Faculty Otorhinolaryngology Department, Ankara, Turkey Email: aceylan@gazi.edu.tr Phone: +90 312 202 64 25 Website: http://websitem.gazi.edu.tr/aceylan Objective: To assess the clinical presentation, location, nerve of origin, diagnosis and treatment of the nonvestibular head and neck schwannomas. Materials and methods: The clinical records of 15 patients with nonvestibular head and neck schwannomas treated at a single institution between 1982 and 2008 were reviewed retrospectively. Results: Eleven (73%) of 15 patients presented with symptoms secondary to mass effect. Facial nerve was the most common localization of schwannoma origin occurring in 6 patients (40%). All schwannomas were resected totally except the one in the pterygopalatin fossa. Three cases of facial schwannoma were found incidentally during chronic otitis media surgery. Conclusion: Facial nerve is one of the most commonly involved localizations for nonvestibular head neck schwannomas. This study indicated that extraordinary sites such as lingual, posterior pharyngeal wall and the suboccipital region may also be the origin of schwannoma. Schwannomas may also be encountered incidentally during chronic otitis media surgery. Complete tumor removal is often achieved, but subtotal resection may be indicated for patients with special indications. Nonvestibular Schwannomas of the Head and Neck Alper Ceylan MD, Fatih Celenk MD, Metin Yilmaz MD, Ozan Gokdogan MD, Erdogan Inal MD Gazi University Medical Faculty Otorhinolaryngology Department, Ankara, Turkey

“Flow‐void” sign at MR imaging: A rare finding of extracranial head and neck schwannomas

The authors present two cases of extracranial head and neck schwannomas that exhibited the "flow-void" sign at MR imaging. In the described cases, MR images showed intratumoral signal voids, which corresponded to dilated vessels. Dynamic contrast-enhanced CT also demonstrated dilated vessels within the tumors on the arterial phase and tumor parenchymal enhancement on the delayed phase. Histopathologic examinations of excised specimens revealed thin-walled, dilated abnormal vessels with or without hyaline degeneration. Schwannoma should be considered when MR images demonstrate the "flow-void" sign in extracranial head and neck tumors.

Rare extracranial localizations of the head and neck schwannomas

Schwannomas are tumors of neurogenic origin, that arise from Schwann cells which surround peripheral, cranial and autonomic nerves. Schwannomas account for only 5% of all benign soft tissue tumors, and 25-45% of extracranial schwannomas are present in the head and neck region. They are usually classified according to the nerve of origin and the site within the head and neck. We presented extremely rare extracranial localizations of schwannomas and discussed about diagnosis and management of these tumors. Schwannomas are slow-growing tumors and late symptoms appearance may cause a delay in diagnosis and treatment of patients with these tumors. An appropriate diagnostic protocol is indispensable tool in performing a differential diagnosis of malignant from benign lesions. Choice of surgical approach depends on schwannomas localization.

Schwannoma in Head and Neck: Preoperative Imaging Study and Intracapsular Enucleation for Functional Nerve Preservation

PurposeIn treating schwannoma patients, it is critical to determine the origin of the tumor to preserve nerve function. We evaluated the validity of preoperative imaging studies in distinguishing the neurological origin of the schwannomas of the head and neck, and the efficacy of intracapsular enucleation in preserving nerve function.Materials and MethodsIn 7 cases of schwannomas in the head and neck region, we predicted whether the tumor originated from the vagus nerve or the cervical sympathetic chain through imaging studies including computed tomography (CT) and magnetic resonance imaging (MRI). All patients were performed intracapsular enucleation, and the function of the vagus nerve and the sympathetic nerve was evaluated preoperatively and postoperatively.ResultsPreoperative imaging studies showed 6 cases where the tumor was located between the carotid artery and the internal jugular vein, and 1 case where the tumor was located posteriorly, displacing the carotid artery and the internal jugular vein anteriorly. At the time of operation, we confirmed schwannoma originating from the vagus nerve on the first 6 cases, and schwannoma originating from the sympathetic nervous system on the last case. All patients went through successful intracapsular enucleation, and of the seven schwannoma cases, 6 patients maintained normal postoperative neurological function (85.7%).ConclusionPreoperative imaging studies offer valuable information regarding the location and origination of the tumor, and intracapsular enucleation helped us to preserve the nerve function.

Schwannomas of the head and neck

Schwannomas are benign encapsulated nerve sheath tumors composed of Schwann cells. Malignant change in head and neck schwannomas is rare, with the incidence varying between 8 and 13.9%. In this review, we discuss the presentation and the management of head and neck schwannomas. The issues and difficulties based on our own experience as well as the experience of published reports from the literature are presented.

Fluid-Fluid Level Formation: A Rare Finding of Extracranial Head and Neck Schwannomas

We present 3 cases of extracranial head and neck schwannomas exhibiting fluid-fluid levels. In the described cases, CT and MR imaging showed predominantly cystic components, intermixed with cellular components. Histopathologic examinations of excised specimens revealed hemosiderin deposition, reflecting intratumoral hemorrhages, which was presumably a cause of fluid-fluid levels. Although fluid-fluid levels are nonspecific findings, schwannoma should be considered when radiologic images demonstrate marked cystic formation with fluid-fluid levels in extracranial head and neck tumors.

Sinonasal schwannoma of the middle turbinate: imaging findings

Paranasal schwannomas are uncommon lesions, representing less than 4% of all head and neck schwannomas. They give rise to nonspecific symptoms such as nasal obstruction, epistaxis, and anosmia. Imaging features are generally nonspecific. Here, we present the radiologic features of a benign schwannoma of the middle turbinate with dural invasion in a 71-year-old woman.

Extracranial Non-vestibular Head and Neck Schwannomas: A Ten-year Experience

We present a series of head and neck extracranial non-vestibular schwannomas treated during a ten-year period, assessing epidemiology, presenting signs and symptoms, location, nerve of origin, diagnostic modalities, treatment and clinical outcome. Clinical records of all patients with head and neck schwannomas treated at our department from April 1995 to July 2005 were retrospectively reviewed. There was female predominance (67%). The mean age at diagnosis was 48 years. Sixteen (76%) presented with a unilateral neck mass. Eleven schwannomas (52%) were in the parapharyngeal space. The most common nerves of origin were the vagus and the cervical sympathetic chain. The tumour may masquerade as a cervical lymph node and other myriad conditions. Treatment for all but 2 cases was complete excision with nerve preservation. Two cases of facial schwannoma required sacrifice of the affected nerve portion with nerve reconstruction. All facial schwannoma patients suffered postoperative facial palsy with only partial resolution (mean final House-Brackman grade, 3.25/6). Among non-facial schwannoma patients, postoperative neural deficit occurred in 12 with partial to complete resolution in 7. The median follow-up period was 24 months. No schwannoma was malignant and none recurred. Non-vestibular extracranial head and neck schwannomas most frequently present as an innocuous longstanding unilateral parapharyngeal neck mass. Preoperative diagnosis may be aided by fine-needle cytology and magnetic resonance imaging or computed tomographic imaging. The mainstay of treatment is complete intracapsular excision preserving the nerve of origin, but for extensive tumour or facial schwannomas, subtotal resection or nerve sacrifice with reconstruction and rehabilitation are considerations. Surgery on intraparotid facial schwannomas carries considerable morbidity and conservative management has a place in treatment. Early recognition of facial schwannomas is key to optimal treatment.

Extracranial Head and Neck Schwannomas: A Clinical Analysis of 33 Patients

To study the clinical features, diagnosis, and management of the extracranial head and neck schwannomas. Retrospective study. The clinical data of 33 patients with schwannoma of the head and neck from 1996 to 2006 were studied retrospectively. Extracranial head and neck schwannomas usually presented as solitary and well-demarcated lesions with insidious course. Although benign, the lesion can cause secondary symptoms, such as nasal obstruction, dysphasia, and hoarseness, relevant to location of the lesion. Fine needle aspiration cytology, computed tomography scans, and magnetic resonance imaging may provide limited implications in the diagnosis of schwannomas, whereas postoperative pathologic examination establishes the final diagnosis. Complete surgical excisions with appropriate approaches have proven to be efficient and successful in the treatment of head and neck schwannomas.

Extracranial Head And Neck Schwannomas

Extracranial head and neck schwannomas are usually benign and rarely malignant tumors of peripheral nerve sheath origin. The clinical presentation of these tumors is reviewed in our series of 21 patients, emphasizing the diagnosis with dynamic infused CT scans. Management is suggested and outcome analysis is provided.

Current management of head and neck schwannomas

The purpose of this review is to discuss the contemporary management of head and neck schwannomas by reviewing the literature and presenting the authors' experience. Molecular studies are attempting to link genetic factors to the development of nerve sheath tumors. Many studies emphasize the importance of preserving the nerve of origin, but structural preservation may not necessarily lead to the preservation of its functional integrity. The importance of neural reconstruction and postoperative rehabilitation is also emphasized. Head and neck schwannomas are uncommon tumors that may affect any peripheral, cranial, or autonomic nerve. This explains their variation in terms of location, clinical presentation, and outcome after surgical resection. History, physical examination, fine needle aspiration, and magnetic resonance imaging are used as diagnostic modalities. Cure entails a complete resection, all attempts being made to preserve the nerve of origin. Otherwise, immediate reconstruction and postoperative rehabilitation should be undertaken in the context of a multidisciplinary management team.

Clinical characteristics and treatment outcome for nonvestibular schwannomas of the head and neck

Purpose Studies involving head and neck schwannomas have focused predominantly on involvement of the vestibulocochlear nerve complex (acoustic neuroma) because of the associated morbidity related to lesions involving that region. However, the majority of head and neck schwannomas are not of vestibular nerve origin and may also produce significant morbidity due to involvement of the orbit, skull base, and cranial nerves. The purpose of this study is to examine the presenting signs and symptoms, location, nerve of origin, and outcome after treatment of patients with nonvestibular schwannomas of the head and neck. Materials and methods The medical and pathological records of all patients with nonvestibular head and neck schwannomas treated at a single institution between 1979 and 1999 were retrospectively reviewed. Results Eighteen (69%) of 26 patients presented with symptoms secondary to mass effect or nerve deficit. The parapharyngeal space was the most common site of tumor origin occurring in 8 patients (31%). The nerve of origin was identified in 16 patients (62%). Twenty-three patients (88%) had complete surgical excision, and 3 patients (12%) had subtotal resection. Postoperative nerve injury occurred in 16 patients (62%) with resolution in 7 patients (44%). Conclusions Nonvestibular head and neck schwannomas occur most commonly in the parapharyngeal space, and presenting signs or symptoms are usually related to mass effect or neural deficit. Complete tumor removal is often achieved, but subtotal or near-total resection may be indicated for patients with extensive skull base, middle ear, or facial nerve involvement. Postoperative morbidity is associated with nerve injury from the surgical approach and/or resection of the involved nerve.

Schwannoma do forame magno: revisão e relato de caso

Os autores relatam um volumoso schwannoma cervical de apresentação incomum, numa paciente do sexo feminino, 53 anos de idade, que em fevereiro de 2002 apresentou queixa de fraqueza progressiva, iniciada há três anos, com dificuldade de mobilização das pernas e braços. Antes da cirurgia foi realizada ressonância magnética da região cervical. No exame físico apresentava postura com aumento da base de sustentação, marcha instável e paraparética, além de diminuição da força nos quatro membros, maior à esquerda, associada a dispnéia. Na ressonância magnética cervical evidenciou-se lesão expansiva extramedular de limites bem definidos, na altura de C1 e C2. Na cirurgia, o volumoso tumor encontrava-se ântero-lateralmente à medula, aderido à raiz esquerda de C1, estendendo-se superiormente através do forame magno, com localização extradural. O diagnóstico de schwannoma foi confirmado pela histopatologia. A paciente evoluiu satisfatoriamente, com melhora progressiva da hemiparesia e hemiparestesia esquerda. A ressonância magnética possibilita a detecção e avaliação da lesão, porém o diagnóstico definitivo só é feito com o exame histopatológico. Dessa forma, o diagnóstico precoce através da ressonância magnética e a exérese cirúrgica tornam-se a melhor forma de abordagem, com bom prognóstico.

Reversal of longstanding optic neuropathy after resection of a paranasal sinus schwannoma

Objectives: Schwannomas are benign, slow-growing, peripheral nerve sheath tumors composed of Schwann cells. Nasal and paranasal nerve sheath tumors are rare, consisting of less than 4% of head and neck schwannomas. Paranasal schwannomas tend to expand into the orbit and anterior cranial fossa. The following case demonstrates the reversal of long-standing optic neuropathy after resection of a benign paranasal sinus schwannoma. Methods: We present a 34-year-old woman with right sided nasal obstruction and progressively worsening vision (20/800) in her right eye. MRI revealed a paranasal sinus mass with extension to the anterior cranial fossa, middle cranial fossa, and orbital apex. Results: Endoscopic biopsy of the mass revealed a schwannoma. The mass was resected via a transfacial, subcranial approach to the skull base using image-guided endoscopic assistance. The mass was removed en block and the patient’s vision returned to normal (20/30) within several hours of surgery. Conclusion: This case illustrates the possible reversal of long-standing optic neuropathy following resection of benign paranasal sinus pathology with optic nerve decompression.

Sympathetic chain paragangliomas of the parapharyngeal space

Objectives: The parapharyngeal space is a complex anatomical feature of the head and neck that contains many important anatomic structures. Masses of the parapharyngeal space have an extensive differential diagnosis. Because of the vascular nature of some of the lesions that can occur in the parapharyngeal space, familiarity with a complete differential diagnosis, as well as radiologic investigation, is of paramount importance. Methods: We present a series of patients who had sympathetic schwannomas and presented with neck masses. Setting: Tertiary academic referral center at Oregon Health and Sciences University. Results: From 1998 to 2003, a series of 5 patients presented to the Otolaryngology Department with head and neck schwannomas of the sympathetic chain. The majority presented with asymptomatic neck masses detected either radiologically or on routine physical examination. All masses were worked up with CT or MRI. A diagnosis was arrived at preoperatively due to the characteristic findings on scan. All lesions were surgically removed. Complications, other than Horner’s syndrome that was expected, were not encountered. Conclusion: Sympathetic chain schwannomas are rarely encountered in the head and neck. When they are, they present as asymptomatic neck masses. Diagnosis can usually be made preoperatively on radiologic criteria. Surgical excision is the treatment of choice, curative, and Horner’s syndrome is to be expected.

上顎洞に発生した神経鞘腫例

Only 2.9% of head and neck schwannomas are found in the nasal cavity or paranasal sinuses. A 47-year-old man preseted with a complaint of left nasal obstruction, rhinorrhea, epiphora and left facial pain. At first, a malignant tumor was suspected, because computed tomography showed a large mass and bony destruction of the left maxillary sinus.It was difficult to make the diagnosis of schwannoma. On biopsy, the intraoperative findings was non-malignant tumor (schwannoma or neurofibroma). Then, complete endscopic excision of the tumor was performed by the Caldwell-Luc method. It is important to resect widely as soon as possible because of the possibility of malignancy.

Extracranial Head and Neck Schwannomas: A Review of 8 Years Experience

Schwannomas of the head and neck are uncommon tumors that arise from cranial, peripheral or autonomic nerves. In this study we review a series of 52 cases of schwannoma originating in the head and neck region over an 8-year period. All the tumors were benign, with the exception of one malignant schwannoma. The age range of the patients studied was 13-76 years and there was a predilection for males. Twenty-five schwannomas occurred in the scalp, face and external ear canal, 9 in the oral or nasal cavity and 18 in the neck. Seven cases of neck schwannoma originating from the major nerve system were found in the parapharyngeal space, all of which were located in the post-styloid compartment. Cervical plexus schwannomas originated either in the peripheral nerves or in an unidentified area of the nervous system; seven tumors were found in the posterior triangle of the neck and two in the anterior triangle. Two of the tumors originating in the brachial plexus were located in the posterior neck and one in the anterior neck. Tumors originating in the vagus nerve or sympathetic chain were all located in the anterior triangle of the neck.

Head and neck schwannomas--a 10 year review.

Schwannomas of the head and neck are uncommon tumours that arise from any peripheral, cranial or autonomic nerve. Twenty-five to 45 per cent of extracranial schwannomas occur in the head and neck region and thus are usually in the domain of the otolaryngologist. They usually present insidiously and thus are often diagnosed incorrectly or after lengthy delays, however, better imaging and cytological techniques have lessened this to some degree more recently. For benign lesions conservative surgical excision is the treatment of choice bearing in mind possible vagal or sympathetic chain injury. Malignant schwannomas are best treated with wide excision where possible. The role of adjuvant therapy remains uncertain and irrespective of treatment modality prognosis is poor with an overall survival of 15 per cent. However, recent advances in ras oncogene inhibitors may hold hope for the future.