Paul J. Del Casino and Jason G. Newman

Fistulas in the neck and face can arise from a variety of sources and present with a multiplicity of symptoms. Alternatively, patients can have fistulas and remain largely unaware of their existence. Once a fistula is suspected by the clinician, a key method for establishing a diagnosis is to categorize them into congenital and inflammatory/infectious etiologies. A thorough patient history is crucial because fistulas are largely slow to develop and are often caused by events in the relatively distant past. Associated infectious symptoms such as fever or previous trauma to the area, as well as a history of similar occurrences as far back as childhood, can be helpful to the diagnostic process.

Imaging for fistulas from congenital sources by computed tomography (CT) or magnetic resonance imaging (MRI) is important when considering treatment. CT may be a useful method for visualizing the sinus or fistulous tract and for evaluating the extent of the lesion. Ultrasonography and fine needle aspiration biopsy may be useful in determining the cystic nature of the lesion in the cases of branchial cleft and thyroglossal duct cysts.

Congenital Fistulas

Branchial cleft cysts

First branchial abnormalities are usually detected in childhood and may present with mucoid discharge from sinus openings above or below the mandible or in the external auditory canal.

Second branchial cleft cysts are among the most common of congenital neck masses, usually occurring in the carotid triangle just below the angle of the mandible and accounting for ~90% of branchial cleft anomalies. They are bilateral in ~2 to 3% of cases. If infected, they may form a deep neck abscess or a draining fistula.

Third or fourth branchial clefts are rare but may also present as a fistulous tract into the lower neck.

Thyroglossal duct cysts: Most thyroglossal duct cysts are found at the level of the thyrohyoid membrane, under the deep cervical fascia. They are remnants of the embryonic thyroglossal duct and may occur anywhere from the base of the tongue to the thyroid gland. They are midline or just off the midline and move up and down upon swallowing. Occasionally, a sinus tract is present in the midline without a visible cyst. This midline sinus tract represents the remnant of the thyroglossal duct. It may open into the region of the hyoid or lower, above the sternal notch.

Infectious Fistulas

Fistulas caused by infectious or inflammatory etiologies are more common than congenital anomalies. History of prior infection or trauma to the area is critical because many fistulas are a result of an inadequately treated cutaneous infection.

Abscess