Imaging of parotid anomalies in infants and children

Juvenile Xanthogranuloma of the Head and Neck: Imaging Findings in 11 Cases

BACKGROUND

Juvenile Xanthogranuloma (JXG) is a non-Langerhans cell histiocytosis, occurring mainly in infancy. With an extracutaneous lesion, its diagnosis is difficult, because of a wide clinical spectrum. Here we demonstrate and characterize imaging features of 11 patients with JXG of the head and neck in various locations.

MATERIAL AND METHODS

We recorded clinical data and reviewed all imaging studies of 11 patients with JXG of the head and neck. Ultrasonography (US) alone was performed in 1 patient; MRI alone in 6 patients; US and MRI in 1 patient; and US, CT, and MRI in 3 patients. We evaluated the following characteristics in all studies: location and number of lesions, echogenicity and vascularization on US, density on CT, signal intensity on T1- and T2-weighted images, ADC and enhancement on MRI, and tumor boundaries and bone involvement.

RESULTS

Lesions were well-defined in 9 cases, and bone erosion was present in 2. On US, lesions were hypoechoic or hyperechoic and with or without vascularization. On CT, lesions were hyper-dense, with no calcification. On MRI, lesions were mildly hyper-intense or iso-intense on T1-weighted images in 8 of 9 patients, hypo-intense on T2-weighted images in 7 of 10, low ADC in 7 of 9, and enhancement in 7 of 7.

CONCLUSIONS

The diagnosis of extra cutaneous JXG may be proposed, with the following suggestive criteria: age < 1 year, well-defined lesion, mild hyper-intensity on T1-weighted images, hypo-intensity on T2-weighted images, low ADC, enhancement, and possible adjacent bone involvement.

Evaluation of the anterior processes of the parotid gland: an ultrasonographic study

OBJECTIVES

This study aimed to determine the prevalence of anterior extensions of the parotid gland (AEPG), namely the accessory parotid gland (APG) and the facial process of the parotid gland (FP), using ultrasonography.

STUDY DESIGN

A total of 338 parotid glands were scanned bilaterally. APG was defined as a soft tissue mass with the same echogenic features as the main parotid gland (MPG) and not in contact with it, while FP was defined as an extension that exceeded the anterior border of the mandibular ramus and was continuous with the MPG. The anteroposterior, mediolateral, superoinferior dimensions and the mean distance from the MPG to the APG were measured.

RESULTS

The prevalence of APG and FP were 19.5% and 36%, respectively, resulting in an AEPG prevalence of 55.6%. The presence of APG was statistically higher in females than in males (p = 0.039). The mean anteroposterior, mediolateral, and superoinferior dimensions of the APG were 18.1 ± 0.57 mm, 0.35 ± 0.17 mm, and 12.3 ± 0.36 mm, respectively, and the mean distance from the MPG was measured as 12.1 ± 0.87 mm.

CONCLUSION

This study can raise awareness among clinicians about the presence of AEPG in the differential diagnosis of mid-cheek masses.

Idiopathic Parotid Gland Abscess in a Pediatric Patient

Parotid abscesses are sequelae of acute parotitis that are rare in pediatric patients. Common inciting causes of parotid abscesses include infection, inflammatory conditions, and ductal obstruction. This case presents a parotid abscess found in an otherwise healthy four-year-old girl. Further evaluation revealed no evidence of infection, no anatomical ductal obstruction, and no evidence of autoimmune conditions that could have caused the abscess. Nonetheless, the patient was treated with an incision and drainage procedure and antibiotic therapy with full recovery. Development of a parotid abscess with no identifiable cause is exceedingly rare with limited documented instances. From this case, idiopathic parotid abscesses may be considered as a diagnosis of exclusion after ruling out common causes, though management still follows the standard of care.