Pneumoparotitis: diagnosis by computed tomography

Pneumoparotid with imaging findings: A case report and review of literature

BACKGROUND

Pneumoparotid is a rare disease associated with retrograde airflow into the ductal system. There is no established treatment for this disease, which has no known complications. Mouth puffing and playing wind instruments are known to be the causes of this disease.

CASE SUMMARY

We managed a case, in which pneumoparotid suddenly recurred 4 months after surgery for purulent parotiditis. The patient did not report any obvious etiological factors, such as mouth puffing or playing a wind instrument. We reviewed 128 articles (from 1941 to 2023) that reported on a total of 166 patients with pneumoparotid, including the patient from the present case report, with imaging findings. This is the first reported case of pneumoparotid following surgery for purulent parotitis. The etiology in our case was classified as idiopathic.

CONCLUSION

Imaging findings could be sufficient for accurate pneumoparotid diagnoses and the exclusion of complications; computed tomography could be useful.

Etiology of Pneumoparotid: A Systematic Review

Pneumoparotid describes retrogradely insufflated air within the Stensen's duct and/or parotid gland. It is a rare condition with variable causative factors. This study aimed to elucidate the clinical characteristics of pneumoparotid. Reports in all languages were evaluated following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement 2020. A literature search was conducted using electronic medical databases (PubMed, Scopus, Web of Science, EBSCO, Ovid, Google Scholar, SciElo, LILIACS, and others) from 1890 to 30 June 2022. One hundred and seventy patients (mean age; 28.4 years) from 126 studies were reviewed. Common symptoms included swelling (84.7%) and pain (35.9%). Characteristic findings were crepitus in the parotid region (40%) and frothy saliva from the orifice (39.4%). The common etiologies included abnormal habits such as blowing out the cheeks (23.5%), idiopathic (20%), self-induced (15.9%), playing wind instruments such as trumpets or flutes (8.8%), and diseases inducing coughing or sneezing (8.2%). The treatments included antibiotic therapy (30%), behavioral therapy to avoid continuing causative habits (25.9%), psychiatric therapy (8.2%), and surgical procedures (8.2%). Treatment should be individualized and etiology-based. However, the etiology was not identified in 20% of patients. Further detailed data from larger samples are required to clarify and improve the recognition of this entity.

Pneumoparotid related to obstructive sleep apnea syndrome treated by oral appliance with anterior opening to reduce intraoral pressure

Pneumoparotid is associated with retrograde air insufflation in Stensen's duct and the parotid gland. A 57‐year‐old man experienced swelling and pain in the right parotid region after sleeping during a flight. Pneumoparotid and obstructive sleep apnea syndrome were diagnosed. Pneumoparotid was suspected as caused by increased intraoral pressure during sleep; thus, an oral appliance to reduce intraoral pressure was effective. After 9 years, the symptoms recurred on the left side. The appliance was reinserted and helped substantially. This is the first case report of obstructive sleep apnea syndrome accompanying pneumoparotid, treated effectively with an oral appliance, with a 10‐year follow‐up.

Pneumoparotid and Pneumoparotitis: A Literary Review

Pneumoparotid is a rare condition of parotid swelling. The presence of the air in gland parenchyma is caused by an incompetent Stensen’s duct with high pressure may cause the acini’s rupture. We reviewed 49 manuscripts, from 1987 to today, that enrolled a total of 54 patients with pneumoparotid. Our review evaluated the following evaluation parameters: gender, age, etiology, clinical presentation, treatment, days of resolution after diagnosis, relapse and complications. The most frequent etiology is self-induction by swelling the cheeks (53.7%). This cause mainly involves children (74%), for conflicts with parents, excuses for not going to school, nervous tics or adults (16%) with psychiatric disorders. Iatrogenic causes are also frequent (16.6%), for dental treatments (55.5%) or use of continuous positive airway pressure (CPAP) (33.4%). Medical therapy is the most practiced (53.7%), in most cases it is combined with behavioral therapy (25.9%) or psychotherapy (25.9%). Surgery is rarely used (9.2%) as a definitive solution through parotidectomy (50%) or ligation of the duct (50%). The most common complication is subcutaneous emphysema (24.1%), sometimes associated with pneumomediastinum (5.5%). Careful treatment and management are necessary to ensure the resolution of the pathology and counteract the onset of complications.

Pneumoparotitis: a case report

BACKGROUND

Pneumoparotid is a rare cause of parotid enlargement. Pneumatic enlargement of the gland is caused by retrograde insufflation via Stensen's duct. Most reported cases have been managed conservatively, thus running a short course.

METHODS AND RESULTS

We report on a case of a 48-year-old man with a chronic painful right facial swelling and symptoms of repeated infection. Clinical examination found a parotid swelling with surgical emphysema and a dilated Stensen's duct. Pneumoparotitis with cystic changes and dilated intraparotid ducts was confirmed by CT. The patient proceeded to undergo excision of the gland, with subsequent resolution of symptoms.

CONCLUSION

Repeated retrograde movement of air and contaminated saliva leads to chronic infection and sialectasis. Management is aimed at preventing these sequelae by identifying and addressing the insult early; however, repeated pneumoparotid leads to chronic pneumoparotitis, the management of which is excision of the gland.

Size-distribution analysis of macromolecules by sedimentation velocity ultracentrifugation and lamm equation modeling

A new method for the size-distribution analysis of polymers by sedimentation velocity analytical ultracentrifugation is described. It exploits the ability of Lamm equation modeling to discriminate between the spreading of the sedimentation boundary arising from sample heterogeneity and from diffusion. Finite element solutions of the Lamm equation for a large number of discrete noninteracting species are combined with maximum entropy regularization to represent a continuous size-distribution. As in the program CONTIN, the parameter governing the regularization constraint is adjusted by variance analysis to a predefined confidence level. Estimates of the partial specific volume and the frictional ratio of the macromolecules are used to calculate the diffusion coefficients, resulting in relatively high-resolution sedimentation coefficient distributions c(s) or molar mass distributions c(M). It can be applied to interference optical data that exhibit systematic noise components, and it does not require solution or solvent plateaus to be established. More details on the size-distribution can be obtained than from van Holde-Weischet analysis. The sensitivity to the values of the regularization parameter and to the shape parameters is explored with the help of simulated sedimentation data of discrete and continuous model size distributions, and by applications to experimental data of continuous and discrete protein mixtures.

Sedimentation analysis of noninteracting and self-associating solutes using numerical solutions to the Lamm equation

The potential of using the Lamm equation in the analysis of hydrodynamic shape and gross conformation of proteins and reversibly formed protein complexes from analytical ultracentrifugation data was investigated. An efficient numerical solution of the Lamm equation for noninteracting and rapidly self-associating proteins by using combined finite-element and moving grid techniques is described. It has been implemented for noninteracting solutes and monomer-dimer and monomer-trimer equilibria. To predict its utility, the error surface of a nonlinear regression of simulated sedimentation profiles was explored. Error contour maps were calculated for conventional independent and global analyses of experiments with noninteracting solutes and with monomer-dimer systems at different solution column heights, loading concentrations, and centrifugal fields. It was found that the rotor speed is the major determinant for the shape of the error surface, and that global analysis of different experiments can allow substantially improved characterization of the solutes. We suggest that the global analysis of the approach to equilibrium in a short-column sedimentation equilibrium experiment followed by a high-speed short-column sedimentation velocity experiment can result in sedimentation and diffusion coefficients of very high statistical accuracy. In addition, in the case of a protein in rapid monomer-dimer equilibrium, this configuration was found to reveal the most precise estimate of the association constant.