Role of the Accessory Parotid Gland in the Etiology of Parotitis: Statistical Analysis of Sialographic Features

Abstract

This retrospective study aimed to identify if the existence of the accessory parotid gland correlated with the etiology of parotitis. This may aid the development of better treatment strategies in the future. Sialographic features of cases with parotitis and healthy subjects were reviewed. The chi-square test was used to compare the incidence of accessory parotid gland between the groups. The Student’s t test was used to compare the length of Stensen’s duct, the length from the orifice to the confluence of the accessory duct, and the angle between the accessory duct and Stensen’s duct between the groups. The incidence of accessory parotid gland in patients with parotitis was 71.8% (28/39), which was significantly higher than that in healthy subjects (P = 0.005). Patients with parotitis had a longer Stensen’s duct than healthy subjects (P = 0.003). There was no significant difference in the length from the orifice to the confluence of the accessory duct or the angle between the accessory duct and Stensen’s duct (P = 0.136 and 0.511, respectively) between the groups.The accessory parotid gland might play a role in the pathogenesis of parotitis. The existence of an accessory parotid gland is likely to interfere with salivary flow. Computational fluid dynamics analysis of salivary flow in the ductal system would be useful in future etiologic studies on parotitis.

MR sialographic assessment of the masseter muscle and the ductal kinking in patients with recurrent parotitis

“…Horsburgh et al [ 16 ] in a series of sialographies measured a mean length of Stensen’s duct of 52.0 mm for healthy patients and 53.0 mm in affected patients. Our measurements are slightly higher than the ones found in the literature; a possible explanation has to be found in the type of imaging measurements: as unique studies [ 15 , 16 ] were conducted on sialographies, the major drawback is that it may create a distorted projection and image that differs from true anatomical size.…”

“…Stensen’s ducts of the parotid glands of male affected subjects were significantly longer than the ones of control subjects ( p = 0.009 and p = 0.006 for study group 2 and study group 1, respectively). Little information is available in the current literature on the anatomy of Stensen’s duct: in a study conducted by Zhu et al [ 15 ] Stensen’s duct mean length in healthy subjects was shown to be 52.0 mm, while in affected subjects 58.0 mm. Horsburgh et al [ 16 ] in a series of sialographies measured a mean length of Stensen’s duct of 52.0 mm for healthy patients and 53.0 mm in affected patients.…”

“…In this regard, gnathologic assessment should be part of the diagnostic work up in patients with recurrent parotitis due to bruxism. A possible association between the angles formed by the confluence of the accessory parotid duct and the Stensen’s duct has been also advocated [ 15 , 16 ] but without a clear relationship with recurrent parotitis.…”

“…Regarding Stensen’s duct anatomy only little information is available on its length and diameter in patients with or without a history of parotitis [ 15 , 16 ]. No study has yet analysed the anatomical relationship between masseter muscle and Stensen’s duct in patients with recurrent parotitis; we investigated, by means of MR sialography, the metrical and morphological relations between those two structures and their implications in the aetiopathogenesis of recurrent parotitis secondary to masseter muscle dysfunction.…”

Contouring the accessory parotid gland and major parotid glands as a single organ at risk during nasopharyngeal carcinoma radiotherapy

“…Based on cadaveric studies, no appreciable histopathological differences from the PGs have been reported (8), and both serous and mucous acini have been identified, suggesting that APG may have similar functions as PGs (9). In most cases, the APG drains into Stensen's duct (parotid duct) through an accessory duct (10). Nonetheless, current guidelines for the delineation of organs at risk (OAR) (11,12) do not account for the APGs, and whether they should be included in the target volume of PGs remains unknown.…”