FLEX February 2024

Imaging of Pediatric Head and Neck Masses

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Fig. 25. JNA. Sagittal fat-suppressed T1 weighted MRI shows an enhancing mass in the left nasopharynx with extension into the anterior cranial fossa ( arrow ).

Benign Neoplasms Juvenile nasopharyngeal angiofibroma

CT is a useful modality for delineating osseous detail, including bony anatomy, expan sion, and erosion ( Fig. 24 ). CT and MRI are complementary modalities in the evalua tion of juvenile nasopharyngeal angiofibromas (JNA), as MRI is superior to CT for detecting intracranial extension of the tumor into soft tissues of the skull base. 31,32 On MRI, these lesions characteristically demonstrate low signal intensity on T1 weighted images, heterogeneous intermediate signal intensity on T2 weighted images, and avid enhancement with flow voids on contrast-enhanced MRI. These MRI features, along with the patient demographics, can help in differentiating a JNA from other nasopharyngeal tumors. 31,32 MRI is useful for preoperative planning by depicting extension of the tumor into the surrounding spaces ( Fig. 25 ). MRI also plays an important role postoperatively for the detection of residual or recurrent tumor and monitoring the effects of radiotherapy.

Fig. 26. Schwannoma. Coronal STIR ( A ) and fat–suppressed postcontrast T1 ( B ) magnetic resonance images show a well-defined T2 hyperintense, homogeneously enhancing mass in the right tongue ( arrows ).

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