Earring lesions of the parotid tail.
OBJECTIVE
Masses in the parotid tail can be a source of consternation to radiologists and clinicians; inaccurate localization may lead to significant iatrogenic complication. We sought to review the pertinent anatomic localizing features of the parotid tail, relevant facial nerve anatomy, and sources of clinical and radiologic confusion. To conclude, we review imaging features that are helpful in generating a diagnosis in this location.


METHODS
We retrospectively reviewed the imaging and clinical features of 111 parotid tail masses in 103 patients (56 male, 45 female, two of unknown sex; age range, 5 months-81 years). The following imaging findings were noted: size, enhancement, multiplicity of lesions, attenuation on CT scans, signal intensity on MR images, and appearance of the surrounding parotid gland. Diagnosis was confirmed by either surgical resection or biopsy findings or by specific clinical data or characteristic imaging findings.


RESULTS
Seventeen types of parotid tail masses were identified. Benign lesions were: pleomorphic adenoma (n = 15), Warthin tumor (n = 14), infectious process (n = 13), venous malformation (n = 9), and Sjögren disease (n = 9), lymphatic malformations (n = 7), lipoma (n = 6), HIV lymphoepithelial lesion (n = 4), first brachial cleft cyst (n = 3), oncocytoma (n = 2), sarcoid (n = 1), and lymph node (n = 1). Malignant lesions were: Non-Hodgkin lymphoma (n = 14), metastatic disease (n = 7), mucoepidermoid carcinoma (n = 4), acinic cell carcinoma (n = 1), and undifferentiated carcinoma (n = 1). Eight patients had two diagnoses.


CONCLUSIONS
Understanding normal parotid tail anatomy is important to radiologists, because accurate localization has implications for appropriate management of masses in this location, potentially reducing the occurrence of marginal mandibular nerve injury.
Hamilton
Bronwyn E
BE
Department of Neuroradiology, University of Utah, Salt Lake City, USA.
Salzman
Karen L
KL
Wiggins
Richard H
RH
Harnsberger
H Ric
HR
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005154:Facial Nerve / Q000033:anatomy & histology; D020220:Facial Nerve Injuries / Q000209:etiology; D005260:Female; D006801:Humans; D007223:Infant; D007431:Intraoperative Complications; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010305:Parotid Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging; D010306:Parotid Gland / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000473:pathology; D010307:Parotid Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000601:surgery; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed