It may also occur as a result of oral surgery, laparoscopy, and cricothyrotomy. In a pneumonectomy, in which an entire lung is removed, the remaining bronchial stump may leak air, a rare but very serious condition that leads to progressive subcutaneous emphysema. Air can leak out of the pleural space through an incision made for a thoracotomy to cause subcutaneous emphysema. On infrequent occasions, the condition can result from dental surgery, usually due to use of high-speed tools that are air driven. These cases result in usually painless swelling of the face and neck, with an immediate onset, the crepitus (crunching sound) typical of subcutaneous emphysema, and often with subcutaneous air visible on X-ray.One of the main causes of subcutaneous emphysema, along with pneumothorax, is an improperly functioning chest tube. Thus subcutaneous emphysema is often a sign that something is wrong with a chest tube; it may be clogged, clamped, or out of place. The tube may need to be replaced, or, when large amounts of air are leaking, a new tube may be added.Since mechanical ventilation can worsen a pneumothorax, it can force air into the tissues; when subcutaneous emphysema occurs in a ventilated patient, it is an indication that the ventilation may have caused a pneumothorax. It is not unusual for subcutaneous emphysema to result from positive pressure ventilation. Another possible cause is a ruptured trachea. The trachea may be injured by tracheostomy or tracheal intubation; in cases of tracheal injury, large amounts of air can enter the subcutaneous space.
Jugular foramen syndrome, or Vernets syndrome, is characterized by paresis of the glossopharyngeal, vagal, and accessory (with or without the hypoglossal) nerves. Symptoms
Symptoms of this syndrome are consequences of this paresis. As such, an affected patient may show:
dysphonia/hoarseness
soft palate dropping
deviation of the uvula towards the normal side
dysphagia
loss of sensory function from the posterior 1/3 of the tongue (CN IX)
decrease in the parotid gland secretion (CN IX)
loss of gag reflex
sternocleidomastoid and trapezius muscles paresis (CN XI)

Causes
Glomus tumors (most frequently)
Meningiomas
Schwannomas (Acoustic neuroma)
Metastatic tumors located at the cerebellopontine angle
Trauma
Fracture of occipital bone
Infections
Cholesteatoma (very rare)
Obstruction of the jugular foramen due to bone diseases
Nasopharyngeal carcinoma spreading into the parapharyngeal space involving the ninth, tenth, and eleventh cranial nerves

Diagnosis
Gadolinium enhanced mri for vestibular schwannoma
mri and biopsy for nasopharyngeal carcinoma
based on nerve palsies
NCCT for occipital bone fracture


== References ==