Preauricular fistula is a type of gill fistula that presents as a small needle-like hole in the front of the ear or at the ear screen, and may even leak a small amount of fluid from the hole. If there is no co-infection, it may be quiet; once it is co-infected, the preauricular fistula will rapidly swell and become pus-filled, causing swelling and pain in the front of the ear and the ear. The disease is not self-healing and, if infected, must be drained by incision to facilitate the drainage of the pus. To cure the disease, a complete removal of the fistula is required. When the fistula is completely removed, the disease is less likely to recur. If the fistula is not completely removed, the surgery may result in a recurrence of the fistula.