Accessory parotid glands are a normal variant and represent ectopic salivary tissue separate from, but usually in close proximity to, the main parotid glands 1. Occasionally the accessory tissue is contiguous with the main glands.
Accessory parotid glands are commonly picked up incidentally on ultrasound; seen in ~20% of the general population 2.
Accessory parotid glands have their own blood supply and secondary duct emptying into the main parotid duct 4.
Accessory parotid glands have the same US echotexture, CT density and MRI signal as the main parotid glands.
Any disorder that affects the main parotid gland may also affect the accessory parotid tissue, but tumours of the accessory parotid glands are rare 5, 6.
- 1. Ramachar SM, Huliyappa HA. Accessory parotid gland tumors. Ann Maxillofac Surg. 2012;2 (1): 90-3. doi:10.4103/2231-0746.95334 - Free text at pubmed - Pubmed citation
- 2. Frommer J. The human accessory parotid gland: its incidence, nature, and significance. Oral Surg. Oral Med. Oral Pathol. 1977;43 (5): 671-6. Pubmed citation
- 3. Ramachar SM, Huliyappa HA. Accessory parotid gland tumors. Ann Maxillofac Surg. 2012;2 (1): 90-3. doi:10.4103/2231-0746.95334 - Free text at pubmed - Pubmed citation
- 4. Skandalakis LJ. Surgical Anatomy. P.M.P. ISBN:9603990744. Read it at Google Books - Find it at Amazon
- 5. Witt RL. Salivary Gland Diseases. Thieme. (2011) ISBN:1604065370. Read it at Google Books - Find it at Amazon
- 6. Afify SE, Maynard JD. Tumours of the accessory lobe of the parotid gland. Postgrad Med J. 1992;68 (800): 461-2. Free text at pubmed - Pubmed citation
- 7. Toh H, Kodama J, Fukuda J et-al. Incidence and histology of human accessory parotid glands. Anat. Rec. 1993;236 (3): 586-90. doi:10.1002/ar.1092360319 - Pubmed citation