The human accessory parotid gland: its incidence, nature, and significance.

Observations on ninety-six dissections of human parotid glands have been presented, with the incidence, size, location, and histologic features of accessory parotid glands noted. Twenty-one per cent of the dissections revealed clearly detached accessory glands at variable distances from the main gland. There were no appreciable histopathologic differences between the accessory gland and the main gland in the same facial half. Aging changes, such as decreased glandular elements, increased fat, and increased fibrous connective tissue, were not more extensive in the accessory gland than in the main gland. Because of the histologic similarity, pathoses of the main gland could also involve the accessory parotid gland. Failure to remove a distantly separated accessory gland during parotidectomy could be a cause of tumor recurrence. X-ray films and sialograms were examined for visualization of accessory parotid glands and their ducts. Whereas routine diagnostic x-ray films were limited in their usefulness, sialograms provided visualization of accessory glands for diagnostic purposes.