Schwannoma de nervio vago cervical / Schwannoma of the cervical vagus nerve

RESUMEN Los schwannomas del espacio parafaríngeo son tumores benignos de la vaina de los nervios pe riféricos y corresponden al 0,09% de todos los tumores de cabeza y cuello; es aún más inusual su localización en el nervio vago. El diagnóstico suele ser desafiante debido a las diversas patologías ubicadas en la región lateral del cuello. Habitualmente se presentan como masas cervicales laterales asintomáticas. Presentamos el caso de un paciente de 42 años que consulta asintomático. Se le realizó tomografía computarizada y angiografía de vasos del cuello. Se procedió a su resección completa, ob jetivándose parálisis de cuerda vocal derecha en el posoperatorio. La disfonía causada por la parálisis de cuerda vocal es una complicación frecuente; si se presenta, debe comenzarse con rehabilitación fonatoria temprana.

ABSTRACT Schwannomas of the parapharyngeal space are benign tumors that arise from the peripheral nerve sheaths and represent 0.09% of all head and neck tumors. Those originating from the vagus nerve are rarer. The diagnosis represents a challenge due to the different conditions encountered in the lateral neck. They usually present as asymptomatic lateral neck masses. An asymptomatic 42-year-old male patient sought medical advice. He underwent computed tomography scan and carotid angiography. The patient underwent complete resection and developed postoperative vocal cord paralysis. Dysphonia due to vocal cord paralysis is a common complication requiring immediate vocal cord rehabilitation.

Endoscopy-assisted transoral resection of a parapharyngeal space schwannoma without mandibular dissection.

Of the schwannomas that arise from the parapharyngeal space, those in the high cervical region are particularly invasive, requiring mandibular dissection. Because these tumors are benign, however, excessive surgical invasion and postoperative neurological complications should be avoided. Postoperative dropout symptoms may be avoided by intracapsular extraction, including nerve integrity monitoring (NIM) and narrow-band imaging (NBI). Video laryngoscopy surgery is reported to be useful for transoral resection of pharyngeal and laryngeal tumors. This report describes the transoral removal of a giant schwannoma located in the high cervical region from a 74-years-old man using a surgical support device without mandibular dissection. The tumor was located on the right lateral pharyngeal wall and extended from the upper oropharynx to the hypopharynx while compressing the epiglottis to the skull base. No separation was observed between the internal jugular vein and the internal carotid artery. The tumor was diagnosed as a schwannoma with no malignancy on the basis of the histology of a core needle biopsy (CNB), and was completely and safely removed endoscopically using NIM and NBI, with no need for an external incision or mandibular dissection. This case illustrates that even a huge sympathetic schwannoma located in the parapharyngeal space at a high cervical position can be excised transorally using video-laryngoscopic surgery (TOVS) without mandibular dissection.

Parapharyngeal Hemangiopericytoma: the Role for Mandibular Proximal Segment Replantation-Review of Literature.

Pharyngeal hemangiopericytoma is a rare tumor .Surgical access to space has been selected based on the location of the tumor in this space, size, and type of pathology. Hemangiopericytoma requires extracapsular dissection. Hemorrhagic nature and tight attachment to adjacent tissues are the other reasons for choosing the surgical approach with the best access. The patient was a 55-year-old female with left-sided facial swelling and dumbbell-shaped lesion involving buccal and lateral pharyngeal space. Brisk hemorrhage happened during biopsy. Submandibular incision, osteotomy of mandibular angle, and temporary proximal segment removal were done. Extracapsular dissection of the lesion performed under direct vision. Proximal segment was returned to the original location and internally fixed with miniplate. Postoperative course was without complication. Mandibular proximal segment replantation technique should be used to treat parapharyngeal tumors with a hemorrhagic tendency.

Contemporary Management of Parapharyngeal Tumors.

PURPOSE OF REVIEW: Management of parapharyngeal tumors is challenging due to the complex anatomic nature of the space and the wide range of pathologies encountered. This article will review the anatomy, common pathologies, and management of parapharyngeal masses. Surgical strategies are also reviewed. RECENT FINDINGS: Masses of the parapharyngeal space are most commonly benign (80%). More recent longitudinal studies have shown that observation and non-surgical therapy are indicated in many cases. When surgery is indicated, innovative endoscopic and robotic-assisted techniques allow for improved visualization and complete tumor removal while avoiding significant blood loss, tumor spillage, and injury to surrounding nerves and vessels. Management of parapharyngeal masses should consider morbidity of surgical resection versus the natural course of the disease. Surgical strategy is determined by location, size, and pathology. Adequate access is needed surgically to ensure complete resection and avoid tumor rupture.

Contemporary management of primary parapharyngeal space tumors.

The parapharyngeal space is a complex anatomical area. Primary parapharyngeal tumors are rare tumors and 80% of them are benign. A variety of tumor types can develop in this location; most common are salivary gland neoplasm and neurogenic tumors. The management of these tumors has improved greatly owing to the developments in imaging techniques, surgery, and radiotherapy. Most tumors can be removed with a low rate of complications and recurrence. The transcervical approach is the most frequently used. In some cases, minimally invasive approaches may be used alone or in combination with a limited transcervical route, allowing large tumors to be removed by reducing morbidity of expanded approaches. An adequate knowledge of the anatomy and a careful surgical plan is essential to tailor management according to the patient and the tumor. The purpose of the present review was to update current aspects of knowledge related to this more challenging area of tumor occurrence.

Peroral fine needle aspiration cytology of parapharyngeal tumors: a study of 67 cases.

Peroral fine needle aspiration cytology (FNAC) was carried out to diagnose parapharyngeal tumors in 67 patients from January 2000 to January 2008. The inflammatory lesions were excluded in the present study. The age of patients ranged from 6 years to 72 years. Analysis of results showed 35 benign tumors and 32 malignant neoplasms. Correlation with histopathology showed a diagnostic accuracy of 92.5% with no false positive report. No complication was encountered in the present study. FNAC can replace incisional biopsy which may be hazardous in this area. Immediate treatment can be planned based on the FNAC report. Such a large series of parapharyngeal tumors diagnosed by FNAC has hardly been reported in India.

Surgical management of parapharyngeal tumors - our experience.

Fifteen cases of parapharyngeal tumors treated surgically in ENT department of Calcutta National Medical College in last 2 years were included, 80% cases were of benign tumors, most common being schwannomas. Most important investigation was found to be CT scan. The study gives an overview regarding the surgical approach, based upon the extent and histology of the tumor and transcervical approach was found to be most efficient for all practical purpose.