Parapharyngeal space schwannomas: our experience and review of literature
Keywords:Parapharyngeal space schwannoma, Management
Background: Tumors of the parapharyngeal space are a rare group of head & neck tumors. Due to their indolent nature they present late with either cranial nerve palsy or lateral neck swelling. The aim of the study was i) to determine the incidence of parapharyngeal space schwannoma among defence personnel’s and their dependents presenting to ENT OPD and ii) to study the clinical presentation, management and outcomes of such lesion.
Methods: The study is a retrospective observational study. All new patients referred to ENT OPD at our center were included in the study. Data was collected from our OPD records over two years between Jan 2015 and Dec 2016.
Results: It was found that the incidence rate of parapharyngeal space schwannoma was 0.034% out of all fresh cases reporting to ENT OPD and 0.47% out of all fresh diagnosed cases of head and neck tumours at our centre. Out of the total 5 cases of parapharyngeal space schwannomas, 2 patients had vagal schwannomas and one each had hypoglossal nerve schwannoma, spinal accessory nerve schwannoma and sympathetic chain schwannoma.
Conclusions: Schwannomas of the parapharyngeal region can be very extensive and may require to be removed in a staged procedure involving the head & neck and neurosurgeons.It is important to distinguish these tumors from other head and neck malignancies by detail clinical and radiological examinations. Despite the benign nature of the disease, the surgery can be morbid with cranial nerve palsies in extensive tumors.
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