Thyroid & Adrenal
Which of the following statements about branchial cleft anomalies is true?
|A||A fistula that lies between the external auditory canal and the submandibular region originates from the second branchial cleft.|
|B||The course of the first branchial cleft fistula is through the bifurcation of the carotid artery|
|C||Injury to the hypoglossal nerve may occur during excision of a second branchial cleft fistula|
|D||The internal opening of the second branchial cleft fistula is usually found in the maxillary sinus|
a. By definition, all branchial remnants are present at the time of birth, although they may not become clinically evident until later in life.
b. In children, fistulas are more common than external sinuses, which are more common than cysts.
c. In adults, cysts predominate.
d. The clinical presentation may range from a continuous mucoid drainage from a fistula or sinus to the development of a cystic mass that may become infected.
e. Branchial remnants may also be palpable as cartilaginous lumps or cords corresponding with a fistulous tract. Dermal pits or skin tags may also be evident.
f. First branchial remnants are typically located in the front or back of the ear, or in the upper neck in the region of the mandible. Fistulas typically course through the parotid gland, deep, or through branches of the facial nerve, and end in the external auditory canal.
g. Remnants from the second branchial cleft are the most common. The external ostium of these remnants is located along the anterior border of the sternocleidomastoid muscle, usually in the vicinity of the upper half to lower third of the muscle. The course of the fistula must be anticipated preoperatively because stepladder counterincisions are often necessary to excise the fistula completely . Typically, the fistula penetrates the platysma, ascends along the carotid sheath to the level of the hyoid bone, and then turns medially to extend between the carotid artery bifurcation. The fistula then courses behind the posterior belly of the digastric and stylohyoid muscles to end in the tonsillar fossa.