Retroauricular arteriovenous fistula.

We present the case of a 70-year-old woman who reported left ear tinnitus with a sudden onset and duration of various months. The main characteristics were pulsatility, synchronicity with pulse and substantial deterioration in recent months. The examination revealed a normal ear and otoscopy, with a pulsating, retroauricular mass of bluish colour and measuring 1 cm×0.5 cm (Fig. 1). We performed an audiometry which revealed binaural sensorineural hearing loss at high frequencies, symmetrical in both ears. We requested a Doppler ultrasound study (Fig. 2) which revealed an anechoic image corresponding to a focal dilatation in the posterior auricular vein. It presented turbulent and pulsatile flow at very high speed (over 500 cm/s). Its spectrum chart presented a low-resistance, arterial pattern. It descended on the sternocleidomastoid, joined the temporomandibular vein and constituted the external jugular vein, which drained into the left brachiocephalic venous trunk.