[Right pyriform sinus fistula with infection of left neck: a case report].

In this article, a case of right pyriform fossa fistula, with left cervical infection as the main manifestation is reported. Ultrasound showed that there was an inhomogeneous echo mass in the dorsal side of the left lobe of thyroid. MRI showed that there were infectious signal behind the bilateral thyroid gland, but mainly on the left side. Fistula was found in the right pyriform fossa under suspension laryngoscope, and CO₂ laser cauterization was performed to cauterize this fistula.