Pneumoparotitis (also termed pneumosialadenitis wind parotitis, surgical mumps, or anaesthesia mumps), is a rare cause of parotid gland swelling which occurs when air is forced through the parotid (Stensen) duct resulting in inflation of the duct.

Signs and symptoms

The size of the swelling is variable, but it is soft and can occur on one side or both sides. It is typically non tender, although sometimes there may be pain. It usually resolves over minutes to hours, however occasionally this may take days. The condition can be transient or recurrent.

Causes

The condition is caused by raised air pressure in the mouth.

Diagnosis and management

Pneumoparotitis is often misdiagnosed and incorrectly managed. The diagnosis is based mainly on the history. Crepitus may be elicited on palpation of the parotid swelling, and massaging the gland may give rise to frothy saliva or air bubbles from the parotid papilla. Further investigations are not typically required, however

sialography Sialography (also termed radiosialography) is the radiographic examination of the salivary glands. It usually involves the injection of a small amount of contrast medium into the salivary duct of a single gland, followed by routine X-ray projection ...

ultrasound Ultrasound is sound waves with frequency, frequencies higher than the upper audible limit of human hearing range, hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hea ...

and

computed tomography A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...

may all show air in the parotid gland and duct. Management is simply by avoidance of the activity causing raised intraoral pressure which is triggering this rare condition.

Prognosis

Recurrent pneumoparotitis may predispose to

sialectasis Sialectasis (also termed sialectasia, or siadochiectasis) is cystic dilation of the ducts of salivary glands. It may be caused by salivary duct strictures or stones (sialolithiasis). It can also rarely be congenital. See also * Bronchiectasis Br ...

, recurrent parotitis, and

subcutaneous emphysema Subcutaneous emphysema (SCE, SE) occurs when gas or air accumulates and seeps under the skin, where normally no gas should be present. ''Subcutaneous'' refers to the subcutaneous tissue, and ''emphysema'' refers to trapped air pockets resembling t ...

of the face and neck, and

mediastinum The mediastinum (from ) is the central compartment of the thoracic cavity. Surrounded by loose connective tissue, it is an undelineated region that contains a group of structures within the thorax, namely the heart and its vessels, the esophagu ...

, and potentially pneumothorax.

Epidemiology

The condition is rare. It is more likely to occur in persons who regularly have raised pressure in the mouth, for example wind instrument players, and balloon and glass-blowers. Cases have also been reported with bicycle tyre inflation, whistling, nose blowing, cough and

valsalva manoeuvre The Valsalva maneuver is performed by a forceful attempt of exhalation against a closed airway, usually done by closing one's mouth and pinching one's nose shut while expelling air out as if blowing up a balloon. Variations of the maneuver can ...

to clear the ears. It can be an iatrogenic effect of dental treatment,

spirometry Spirometry (meaning ''the measuring of breath'') is the most common of the pulmonary function tests (PFTs). It measures lung function, specifically the amount (volume) and/or speed (flow) of air that can be inhaled and exhaled. Spirometry is he ...

, and

positive pressure ventilation Modes of mechanical ventilation are one of the most important aspects of the usage of mechanical ventilation. The mode refers to the method of inspiratory support. In general, mode selection is based on clinician familiarity and institutional pref ...

. Apart from these factors, the condition mainly occurs in adolescents, often self-inflicted due to psychological issues.

References

{{Oral pathology Salivary gland pathology