The accessory parotid gland and facial process of the parotid gland on computed tomography

Abstract

The purpose of this study was to determine the incidence of an anterior extension of the parotid gland, such as an accessory parotid gland (APG) or facial process (FP) and to evaluate its characteristics on computed tomography (CT) scans. We reviewed CT scans of 1,600 parotid glands from 800 patients. An APG on CT was defined as a soft-tissue mass of the same density as the main parotid gland, located at the anterior part of the main parotid gland, and completely separate from the main parotid gland. An FP was defined as a lobe of the parotid gland protruding anteriorly over the anterior edge of the ramus of the mandible on CT and showing continuity with the main gland. The overall incidence rates and characteristics of APGs and FPs were evaluated according to age, sex, and side. The incidence rates of APGs and FPs were 10.2% (163/1,600) and 28.3% (452/1,600), respectively. The mean size of an APG was 15.8 mm × 5.0 mm and the mean distance from the main parotid gland was 10.5 mm. The FP reached anteriorly between the anterior edge of the mandibular ramus and the anterior border of the masseter muscle in 405 (89.6%) cases, while it extended over the anterior border of the masseter muscle in 47 (10.4%) cases. The incidence rates of APGs and FPs decreased and increased, respectively, with increasing age, showing significant linear correlations. However, the incidence of an anterior extension of the parotid gland (either an APG or an FP) was similar across all age groups. The present study showed that CT might be helpful in identifying anterior extensions of the parotid gland including APGs and FPs. The anatomical information gained from this study contributes to a better understanding of APGs and FPs and how their incidence changes with age.

Dedicated Verification of an Accessory Parotid Gland via Minimal-Activity PSMA-PET/CT

“…Although other tumors of the head and neck, such as adenoid cystic carcinoma, squamous cell carcinoma, or medullary thyroid cancer, may also be PSMA-positive ( 7 – 9 ), in our patient, a right-sided accessory parotid gland was highly probable owing to corresponding magnetic resonance imaging findings and PSMA uptake intensity. An accessory parotid gland is defined as a separated salivary gland anterior to the proper parotid gland and appears in 10% of humans ( 10 ). Although it is characterizable in morphologically oriented examinations such as CT, PSMA-PET/CT can help clarify the diagnosis for ambiguous cases in a descriptive manner.…”

Mucosa-associated lymphoid tissue lymphoma of the accessory parotid gland presenting as a simple cheek mass

“…The accessory parotid gland is a variation of the anteriorly extended parotid gland. [11] This gland may be either continuous with or separated from the main parotid gland. [11] Among the tumors that may arise in the parotid gland, NHL only accounts for 1% to 4%, [1,4] with subtypes including follicular lymphoma, diffuse large B-cell lymphoma, and MALT lymphoma.…”

“…[11] This gland may be either continuous with or separated from the main parotid gland. [11] Among the tumors that may arise in the parotid gland, NHL only accounts for 1% to 4%, [1,4] with subtypes including follicular lymphoma, diffuse large B-cell lymphoma, and MALT lymphoma. [6] Of these subtypes, development of MALT lymphoma in the parotid gland is rare [1,5] ; further, its development in the accessory parotid gland is especially rare, and such cases have scarcely been reported.…”

Review of 18F-Fluciclovine PET for Detection of Recurrent Prostate Cancer

“…Anatomic variants are most relevant in the head and neck. The salivary glands demonstrate moderate FACBC uptake, and accessory parotid glands are seen in up to 15% of the general population (Fig 26), with an additional 30%-35% of the general population demonstrating a prominent anterior facial process of the parotid gland (at CT) (26). These processes typically are seen lateral to the masseter muscle and anterior to the bulk of the parotid gland.…”