Branchial Cleft Cyst

Branchial cleft cysts are often asymptomatic, but can often become tender, enlarged, or inflamed with superinfection or abscess formation during episodes of upper respiratory tract infections. The patient can present with purulent drainage of the sinus to skin or pharynx in such situations. The most concerning symptoms include dysphagia, dyspnea, and stridor due to cyst compression of the upper airway.[14] Cystic lesions are more common than fistulae, but they usually present later, usually in the second decade of life. Cysts most often present as non-tender soft-tissue masses beneath the sternocleidomastoid muscle. However, they may present with acute infection. Change in size during upper respiratory infections is noted in up to 25%. 

The physical examination will differ depending on the location of the branchial cleft cyst.

• A first branchial cleft cyst is typically smooth, non-tender, fluctuant mass found between the external auditory canal and submandibular area and frequently will have a cutaneous punctum from which fluid may be expressed. It is variably involved with the parotid gland and facial nerve, and there may be a connection to the middle or external ear so an otologic exam is crucial in these patients.[15]

• A second branchial cleft cyst is typically identified by a pit or punctum of the skin at the lower anterior border of the sternocleidomastoid and may connect to the tonsillar fossa of the pharynx. It can be in proximity to the glossopharyngeal and hypoglossal nerve as well as carotid vessels. The cysts are tender if secondarily infected, and in severe cases may lead to airway compromise. If it is associated with a sinus tract, mucoid or purulent discharge may be present on the skin or into the pharynx.[16][17]

• Third and fourth branchial cleft cysts are rare. They are normally on the left side of the neck or the suprasternal notch/clavicular area. Typically they present as a firm mass or infected cyst draining to the piriformis sinus or external neck skin. These fistulae are more likely to present when infected and they may have undergone repeated incision and drainage procedures owing to incorrect diagnosis and subsequent recurrence.[18]

There is no specific laboratory test needed for evaluation. [17][19][20]

Imaging Studies

• If a sinus tract present, a sinogram can be obtained by injecting radiopaque dye to delineate the course and determine the size of the cyst.
• Ultrasonography can be obtained to determine the cystic characteristics of the cyst.[1][19]
• Contrast-enhanced CT will depict a cystic and enhanced mass in the neck.[20]
• MRI can be used for a finer resolution.[21]

Fine-needle aspiration is helpful to distinguish a branchial cleft cyst from malignant neoplasm.[16]

The treatment of a branchial cleft cyst is elective excision due to the risk of infection, further enlargement, or an extremely low risk of malignancy. So long as there is no airway compromise or frank abscess, there is typically no urgency; clinicians can defer excision beyond 3 to 6 months of age or allow treatment of an acute infection.[5] However, in the event of airway compromise or large abscess emergent surgery may be required [22][23]. Systemic antibiotics and aspiration are generally preferable to incision and drainage which might produce more distortion of the surgical planes.[24]

The incision is planned to optimize cosmesis, placing it within a natural skin crease whenever possible. If a fistula or sinus is present then identifying the tract by gentle insertion of a probe or catheter is important in order to ensure complete excision and decrease chance of recurrence. Methylene blue can be used by dipping a lacrimal probe in the solution and inserting it into the tract to make it easier to identify intraoperatively. Dissection should be performed carefully over the surface of the lesion as the tract can be thin-walled. If the track is long, then exposure should be obtained by using a second "stepladder" incision placed within a skin crease cephalad to the primary incision. In first branchial cleft cysts, initial exposure of the main trunk of the facial nerve and branches should be performed with a superficial parotidectomy approach to reduce the risk of facial nerve injury, as the anomaly can be intimately associated with the nerve. Preoperative fistulograms can also be useful.[9][25] In the event that a patient cannot undergo surgery, ethanol ablation has been used as an alternative in this patient population, though is not usually recommended as a primary treatment.[9][26]

Third and fourth branchial cleft cysts are treated with a standard transverse cervical incision to identify the recurrent laryngeal nerves, occasionally requiring thyroid lobectomy to completely excise the tract to the piriform sinus. Before the trans-cervical portion of the surgery is begun, direct laryngoscopy is performed to confirm diagnosis, and to allow endoscopic cannulation of the opening into the piriform sinus to facilitate dissection during excision.[5][27]

Differentials include:[1]

• Lymphadenopathy
• Hemangioma
• Carotid Body Tumor
• Cystic Hygroma
• Ectopic Thyroid/Salivary Tissue
• Vascular Neoplasm/Malformation
• Thyroglossal Duct Cysts
• Cat Scratch Disease
• Atypical Mycobacterial Infections
• Cystic Squamous Cell Carcinoma

Patients and families should be educated that branchial cleft cysts are typically benign, and with treatment, patients generally recover without complications or recurrence. 

Once branchial cleft cysts are excised, recurrence is relatively uncommon. There is an estimated risk of 3%. However, if previous surgery or recurrent infection has occurred, recurrence can be as high as 20%.[5]

An otolaryngologist or pediatric otolaryngologist should be consulted in these cases depending on the age of the patient.

Branchial cleft anomalies are congenital malformations and currently, there are no preventative measures to reduce the likelihood of presentation. Patients and physicians should be educated on the symptomatology and physical exam findings that could lead to the early diagnosis of these lesions. This could reduce the cost of care for the patient, which would otherwise consist of future physician visits, multiple courses of antibiotics, and diagnostic imaging. 

The management of patients with branchial cleft cysts is interprofessional. The surgery is usually performed by an otolaryngologist or, rarely, by a pediatric surgeon. However, the follow up may be required by a nurse practitioner, pediatrician, or primary care provider. Surgery is the only treatment for branchial cleft cysts. Two well-known complications are recurrence and infection. Specialty trained nurses in the fields of otolaryngology are involved in family education, patient monitoring, and patient feedback. In rare cases, injury to the facial nerves may also occur., which could require further surgery. The outcomes after branchial cleft cysts are excellent with a recurrence rate of about 3% to 7% (Level V). [24][25]