Diagnostic ultrasound ( PDFDrive )

1654 PART V Pediatric Sonography
A
B
FIG. 48.45 Dermoid Cyst. Gray-scale (A) and color Doppler (B) transverse images show a well-deined, right paramidline, avascular infrahyoid
lesion containing internal echoes and posterior through transmission. The lesion is in the deep subcutaneous layer, immediately supericial to the
strap muscles.
A
B
FIG. 48.46 Cervical Teratoma. (A) Poor deinition of soft tissue planes caused by a complex iniltrative mass containing cystic, solid, and calciied
areas (arrow). (B) Axial T2-weighted magnetic resonance image shows complex cystic and solid mass iniltrating the parotid, masseter, submandibular,
parapharyngeal, and carotid space soft tissues.
recommended because these anomalies are at risk for rupture
or infection, and 5% will undergo malignant degeneration to
squamous cell neoplasms. 93,98
Teratomas
Cervical teratomas are rare, occurring in 1 per 40,000 live births
but representing 5% to 14% of all neonatal teratomas. 154-156 hese
lesions are believed to arise from pluripotential cells of two or
three germ layers isolated at sites distant to the anatomic site of
origin. 154,157 About 90% of childhood teratomas consist of all
three germ layers with variable diferentiation, and 75% to 85%
of head and neck tumors contain neuroectodermal tissue. 154 Most
cervical teratomas are benign, with rare malignant diagnosis. 156,157
hese lesions typically occur as a large, iniltrative cystic and
solid mass in the anterior and lateral neck. 5,156 Airway impingement
is the most common cause of morbidity; therefore, prenatal
identiication of the lesion may help deine management at
delivery. 156,158 Sonography demonstrates a multilocular heterogeneous
mass containing solid and cystic components, with
calciications in 50% of cases 156,158,159 (Fig. 48.46). Mortality
approaches 100% if the lesions are not immediately managed
and resected. 158,160
Vascular Lesions
Vascular Anomalies
In 1982, Mulliken and Glowacki 161 proposed a classiication
separating vascular anomalies into two groups, tumors versus