Ultrasound findings in 156 children with 169 pilomatricomas.

Background: Cutaneous lesions present a diagnostic challenge to radiologists and clinicians alike. Pilomatricoma is the second most common skin neoplasm in childhood, yet there are limited reports in the literature focusing on imaging in pediatric patients.

Objective: To characterize the typical and atypical US features of pilomatricoma in pediatric patients and to determine the performance of the adult-based Solivetti classification for assessing pilomatricomas in children.

Materials And Methods: We retrospectively reviewed 169 US scans of pathologically proven pilomatricomas in 156 children performed over a period of 66 months. We evaluated images for the size of the lesion, borders, morphology, content, calcification, location on the skin and Doppler characteristics.

Results: Most of the pilomatricomas presented as single dermohypodermic lesions with peripheral vascularity on color Doppler interrogation. The cheek was the most common location, followed by the arm. Solivetti type 2 US pattern was the most frequent, and peripheral hypoechoic halo was only observed in this type. One child had an anetodermic pilomatricoma, and 11 children had multiple lesions.

Conclusion: We showed that pilomatricomas exhibit variable sonographic patterns. In our cohort, less than 50% of the lesions showed the characteristic hypoechoic rim and less than 30% of the cases presented as diffusely hyperechoic masses with posterior acoustic shadowing. Our results show that the Solvetti classification for the US assessment of pilomatricomas can be of value in children.