Glossopharyngeal and vagus nerves are the 9th and 10th cranial nerves. These two nerves are grouped together as both nerves exit the brainstem side by side, and have similar functions and distributions anatomically.
A schwannoma is the abnormal growth of Schwann cells, which line and insulate the nerves. Vagal schwannoma is a tumour of the vagus nerve, the longest cranial nerve that controls involuntary processes such as controlling vocal cords. It is a rare tumour that is usually benign, slow growing and rarely spreads to other parts of the body (malignancy). Vagal schwannoma is usually asymptomatic but can cause swelling in the neck, hoarseness and uncontrollable cough. Glossopharyngeal schwannoma’s are a less common form of tumour of the glossopharyngeal nerve. Symptoms of these types of schwannoma include loss of hearing, vertigo, difficulty in walking and coordination, hoarseness of voice, and headache and are usually non-specific in nature.
Your doctor diagnoses vagal schwannoma on the basis of your symptoms and by examining tissues removed surgically (biopsy). Your doctor may order other tests such as CT scan and carotid angiogram (an imaging test that uses a special dye and X-ray images to detect blockages in the carotid arteries). Glossopharyngeal schwannoma is also diagnosed on the basis of clinical symptoms and imaging studies such as MRI scan and by examining tissues removed surgically.
Treatment of vagal and glossopharyngeal schwannoma involves surgical resection. Some cases involve tereotactic radiosurgery (a type of non-invasive treatment that delivers gamma radiation at the tumour site without making an incision). The chances of recurrence with these types of tumours after surgery are very rare.