Sonographic Features of Auricular Pseudocyst.

A 9-year-old boy was seen for an asymptomatic lesion of 7 months duration on the right pinna. The lesion first appeared after trauma and had grown progressively since then. The lesion had been drained twice with subsequent recurrence. Culture of the serous effusion was negative. The physical examination showed an indurated fluctuant nodule measuring 1.6 by 0.9 cm on the superior right antihelix (Fig. 1a). Skin ultrasound revealed a hypoechoic cystic lesion with anechoic content, no wall (asterisk), and posterior reinforcement, measuring 2.09 by 1.58 cm (Fig. 1b; longitudinal section, B mode, 18 Mhz). There was no increased intralesional or perilesional blood flow in the Doppler images (Fig. 1c). The lesion was diagnosed as an