para>Most occur in the pediatric age group á
EPIDEMIOLOGY
- Predominant age: By definition, all branchial cleft fistulae are present at birth; however, they may remain unnoticed for some time.
- Branchial cleft cysts may not present until adulthood and are commonly diagnosed in the 3rd and 5th decades of life.
- Predominant sex: male = female
Incidence
Unknown á
Prevalence
Unknown á
ETIOLOGY AND PATHOPHYSIOLOGY
- Branchial anomalies result from the incomplete obliteration of pharyngeal clefts and pouches during embryogenesis.
- Both respiratory and squamous epithelium (alone or together) may line branchial anomalies.
- Squamous epithelium is found more commonly in cysts.
- Ciliated, columnar epithelium is found more commonly in sinuses and fistulae.
- The 1st branchial cleft contributes to the external auditory canal, middle ear cavity, mastoid air cells, and eustachian tube. Related fistulae are very rare and tend to be infra- or retroauricular. Preauricular cysts and sinuses are not thought to be of branchial cleft origin:
- 1st branchial cleft anomalies enter the external auditory canal and/or occasionally the middle ear.
- They represent 1-4% of all branchial cleft malformations.
- Type I anomalies contain ectodermal elements only and course lateral to the facial nerve.
- Type II anomalies contain ectoderm and mesoderm, coursing medial to the facial nerve.
- The 2nd branchial cleft forms the hyoid bone and tonsillar fossa. Related fistulas (most common variant) course between the internal and external carotid arteries:
- 2nd branchial anomalies represent 90-95% of all branchial cleft lesions.
- They course close to the glossopharyngeal and hypoglossal nerves, entering the pharynx at the level of supratonsillar fossa.
- The external opening runs along anterior border of sternocleidomastoid muscle.
- 2nd branchial cleft anomalies are subdivided into four subtypes:
- Type I lesions are anterior to the SCM and do not involve the carotid sheath.
- Type II lesions are the most common second arch anomalies, deep to the SCM, and anterior or posterior to the carotid artery.
- Type III lesions pass between the internal and external carotid arteries and are adjacent to the pharynx.
- Type IV lesions are medial to the sheath, adjacent to the tonsillar fossa.
- The 3rd and 4th branchial clefts form the parathyroid glands, thymus, and portions of thyroid gland (parafollicular cells):
- 3rd branchial cleft anomalies represent 5% of all branchial anomalies.
- Sinus tracts (also called pyriform sinuses) originate in the pyriform sinus and course adjacent to the thyroid cartilage.
- Fistulas are rare, usually resulting from recurrent infections and/or repeated surgery.
- Both 3rd and 4th fistulas should have external ostia on the lower anterior neck. Left-sided lesions are more common than right-sided ones.
- They are often called pyriform sinus "fistulae,"Ł despite the frequent lack of an external opening to the skin.
- Those from the 3rd branchial cleft course posterior to carotid artery.
- Differentiated from 2nd branchial cleft anomalies by the location of their internal opening (external openings should be the same)
- Presence of thymic tissue does not differentiate between 3rd and 4th branchial cleft anomalies, as accessory thymic tissue has been described in the latter (1).
Genetics
10% have family history. á
RISK FACTORS
Positive family history á
COMMONLY ASSOCIATED CONDITIONS
Microtia and aural atresia occur with failure of development of the 1st branchial cleft. á
DIAGNOSIS
HISTORY
- History of drainage from the cervical area
- Neck abscess or suppurative thyroiditis
PHYSICAL EXAM
- Presence of a tiny external opening usually on middle to lower neck along anterior border of sternocleidomastoid muscle
- Spontaneous mucoid drainage
- External openings may be marked by a skin tag or cartilage.
- Infection may be the presenting sign: Erythema, swelling, pain, or fever may also be present.
- Thyroid abscesses in children often represent an underlying branchial remnant, especially with (+) mixed-flora cultures (2).
- 10% are bilateral.
- Small orifices located in the mid-neck, most commonly along the anterior border of the sternocleidomastoid muscle (less commonly in the lower neck or postauricular)
- 3rd and 4th branchial cleft anomalies are predominantly left-sided (89%) (1).
DIFFERENTIAL DIAGNOSIS
- External sinuses
- Cystic hygroma
- Dermoid cysts
- Lymphadenopathy
DIAGNOSTIC TESTS & INTERPRETATION
Culture if signs of infection á
- CT of neck with IV contrast is occasionally beneficial in 3rd and 4th branchial cleft fistulas/sinus (2)[C].
- CT may demonstrate the fistula tract in up to 64% of cases (3).
- MRI and US may also be useful to define the tract.
- A barium esophagogram may demonstrate the fistula tract and location; sensitivity rate of 50-80% when used to evaluate 3rd and 4th branchial anomalies (3)[C].
- An incisional biopsy should not be performed in children because this may make subsequent resection more difficult.
- Contrast diagnostic modalities are more accurate in the noninfected state due to reduced edema and improved contrast penetration into the fistula tract.
Diagnostic Procedures/Other
- Sinogram or fistulogram may be done but are usually of little value.
- Upper airway endoscopy may be useful to visualize the opening into the pharynx.
Test Interpretation
- Cysts are more commonly lined by stratified squamous epithelium and may contain hair follicles, sweat glands, sebaceous glands, or cartilage.
- Sinuses and fistulae are more commonly lined by ciliated, columnar epithelium.
TREATMENT
- Complete surgical excision is required to prevent recurrence (4).
- Outpatient status is usually appropriate.
- Acute infections should be treated with antibiotics first; if this fails to resolve, incision and drainage may be required (3). Typical offending organisms include Streptococcus and Klebsiella, although infections may be polymicrobial.
- If possible, an elective resection should be scheduled weeks after the acute infection.
SURGERY/OTHER PROCEDURES
- Stepladder incisions may be needed to visualize the upper portion of the tract.
- 1st branchial cleft lesions may require larger incisions.
- Methylene blue injection into the fistula may be useful, although spillage complicates the dissection.
- Cannulation of the tract or fistula with a 2-0 or 3-0 monofilament suture may aid in establishing the course of the tract.
- Drains are not routinely used.
- For 3rd and 4th arch anomalies, fiberoptic endoscopy may assist in locating the opening into the pyriform sinus.
- 4th arch fistulas require an ipsilateral hemithyroidectomy to remove the tract; partial resection of the thyroid cartilage may be required to gain exposure to the tract as it enters the pyriform sinus (3).
- Antibiotics are used only for infection.
- Patients with abscesses related to 3rd branchial cleft anomalies frequently require initial incision and drainage (1)[B]:
- Incision and drainage failure rates is ~94% on the first attempt.
- Virtually all will require resection.
- Those with acute suppurative thyroiditis may require partial thyroidectomy and removal of the fistula tract. Partial thyroidectomy is rarely curative (1)[B].
- Endoscopic cauterization of the internal orifice has been successfully used in some cases, especially in children <8 years (1)[B].
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Patient Monitoring
- If infected, follow at weekly intervals until resolution of abscess and inflammatory reaction; then excise.
- Postoperative visit at 2 to 3 weeks
- Lack of epithelium in the fistula tract pathology specimen may indicate incomplete resection; have a high index of suspicion for future recurrence.
PROGNOSIS
Good á
COMPLICATIONS
- Facial nerve injury (1st arch anomalies)
- Hypoglossal nerve injury
- Spinal accessory nerve injury
- Vagus nerve injury
- Infection
- Carotid artery injury
- Recurrence (full excision of tract epithelium required)-common with 1st arch anomalies due to incomplete excision.
- Neoplastic degeneration of branchial remnants (~250 reported cases) if not resected
REFERENCES
11 Nicoucar áK, Giger áR, Jaecklin áT, et al. Management of congenital third branchial arch anomalies: a systematic review. Otolaryngol Head Neck Surg. 2010;142(1):21.e2-28.e2.22 Liberman áM, Kay áS, Emil áS, et al. Ten years of experience with third and fourth branchial remnants. J Pediatr Surg. 2002;37(5):685-690.33 Waldhausen áJH. Branchial cleft and arch anomalies in children. Semin Pediatr Surg. 2006;15(2):64-69.44 Roback áSA, Telander áRL. Thyroglossal duct cysts and branchial cleft anomalies. Semin Pediatr Surg. 1994;3(3):142-146.
CODES
ICD10
Q18.0 Sinus, fistula and cyst of branchial cleft á
ICD9
744.41 Branchial cleft sinus or fistula á
SNOMED
Fistula of branchial cleft á
CLINICAL PEARLS
- Most common: 2nd branchial cleft anomalies: an opening in the mid-neck at the anterior border of the sternocleidomastoid muscle with a history of an occasional discharge is diagnostic.
- Radiographic confirmation is not needed; complete surgical excision as an outpatient is both diagnostic and therapeutic.
- Branchial cleft remnants, sinuses, and cysts result from the failure of branchial arches to close and/or complete their normal development.