Medical Therapy
If the cyst is infected, treatment with an antibiotic is indicated before planning surgical excision. Complete resolution of inflammation allows for an easier and safer dissection.
Appropriate intravenous antibiotics that cover upper airway pathogens include ampicillin and sulbactam (Unasyn), clindamycin, and several other drugs. Oral antibiotics can be used after the infection has improved greatly on intravenous antibiotics and for minimally infected lesions. Appropriate oral antibiotics include amoxicillin (Augmentin), clindamycin, and several other agents.
Base the final choice of antibiotics for both intravenous treatment and oral treatment on culture and sensitivity results; therefore, needle aspiration of an acutely infected cyst early in the course of treatment is often helpful.
Macrocystic lymphatic malformations have been shown to be responsive to the sclerotherapy agent OK-432. OK-432 is a biologic preparation of lyophilized powder containing Streptococcus pyogens (group A streptococci) treated with benzylpenicillin potassium. Research with OK-432 is ongoing, but several authors have reported complete or substantial response with 4 injections of this agent given 6-8 weeks apart. Patients with microcystic disease did not respond to this treatment.
Surgical Therapy
Complete surgical excision is the goal when treating branchial cleft anomalies and thyroglossal duct cysts (TGDCs). Unless dangerous compromise of the aerodigestive tract is present, avoid incision and drainage procedures. These procedures often obscure planes and make future complete surgical excision more difficult.
A study by Chung et al indicated that in the treatment of TGDCs, ethanol ablation has a higher rate of treatment failure than does surgery but results in fewer complications. According to the study, the treatment failure rate for ethanol ablation was 19.6%, compared with 2.4% for whole surgery and 1.2% for the Sistrunk operation. However, ethanol ablation had a complication rate of 1.8%, versus 10.0% for whole surgery and 10.2% for the Sistrunk operation. [10]
Surgical excision is an excellent option for lymphatic malformations that can be removed without sacrificing important adjacent structures. However, lymphangiomas and cystic hygromas frequently involve adjacent structures, which can lead to high complication rates. Infrahyoid lymphatic malformations without mediastinal involvement have been shown to have the most favorable outcome with surgical excision.
Preoperative Details
See Medical therapy.
Intraoperative Details
First branchial anomalies
Excise branchial cleft anomalies under general anesthesia. Avoidance of paralytic agents by the anesthesia team is necessary in order to identify and dissect out the facial nerve. A parotidectomy incision is made with incorporation of an ellipse of skin around any prior surgical scars or sinus and fistula tracts. An s-shaped parotidectomy incision starting in the preauricular crease and extending under the mandible is appropriate.
When operating on younger children, be aware that the typical cartilaginous pointer and styloid process landmarks often are not present or are poorly developed. In these cases, the facial nerve is just deep to the parotid fascia; therefore, locating the nerve first in the neck is safer. The facial nerve is found in the triangle formed by the anterior border of the sternocleidomastoid muscle, the posterior belly of the digastric muscle, and the cartilage of the external auditory meatus.
Once the facial nerve is identified, the bifurcation and the upper and lower divisions are exposed completely with meticulous dissection. The sinus or fistula tract is dissected with a narrow cuff of normal tissue. Lacrimal probes and dilators can help identify and facilitate the dissection of a first branchial cleft fistula. The tract may be located either superficial or deep to the facial nerve.
If required, the freely dissected branchial cleft anomaly is passed over or under the main branches of the facial nerve. For complete removal, a small portion of the external auditory cartilaginous canal may need to be excised along with the tract. The tract rarely involves the tympanic membrane, which requires a tympanoplasty for complete removal.
Second and third branchial anomalies
A horizontal skin incision is made in a natural skin crease, incorporating any prior incisions or sinus tracts in an ellipse. Flaps are raised, paying close attention to protect the marginal mandibular branch of the facial nerve. After the inferior aspect of the cyst is dissected free, the dissection is carried superiorly along the tract. As the tract crosses over the hypoglossal nerve, bleeding is often encountered from the lingual venous plexus. When controlling this bleeding, care must be taken not to injure the hypoglossal nerve.
The tract is then followed between the internal and external carotid arteries with second arch anomalies or posterior to the internal carotid artery with third arch anomalies. If no internal opening is present, the tract can be ligated just as it passes deep to the posterior belly of the digastric muscle. A tonsillectomy may be required for complete excision of second branchial arch anomalies with an internal opening present in the tonsillar fossa. A thyroid lobectomy is required during the excision of a third branchial cleft anomaly.
If the fistula tract is long, a useful technique involves making 2 separate horizontal skin incisions. This stepladder technique, with one low cervical incision and a higher incision at the level of the hyoid bone, allows for excellent exposure without excessive trauma from heavy traction on the skin flaps. Avoid vertical skin incisions because the resultant scar is cosmetically unappealing.
Fourth branchial anomalies
Although controversy remains regarding the identification of third and fourth branchial sinuses, most authors recommend complete excision of the cyst along with the sinus tract. Verret et al reported a series of 10 patients with fourth branchial cleft anomalies who were treated with endoscopic cauterization of the sinus tract. [11] In this procedure, a direct laryngoscopy is performed and an intravenous balloon catheter, or angiocath, is passed into the sinus tract located at the apex of the pyriform sinus. The balloon is then inflated to dilate the opening of the sinus. An electrocautery ball coagulator is placed into the sinus tract opening and, with coagulation and manipulation, the tract is closed.
Thyroglossal duct cysts
The suggested surgical approach to the TGDC is the Sistrunk operation. The operation includes excision of the cyst in continuity with the mid portion of the body of the hyoid bone and a small block of muscle around the foramen cecum. The procedure is performed under general anesthesia with a shoulder roll in place.
A skin incision is made in a natural skin crease near the cyst; any previous incisions or sinus tracts are included in the ellipse. A superior flap is raised to the level of the hyoid bone, and an inferior flap is raised until the inferior aspect of the cyst is identified. The strap muscles are separated, and the cyst is dissected from the surrounding structures until it is attached only to the hyoid bone superiorly. The body of the hyoid bone is skeletonized and then transected on each side of the pedicle. A curved retractor is placed transorally, which facilitates excision of the tract up to the base of tongue with the inclusion of a 5-10 mm core of muscle.
Postoperative Details
A Penrose drain, or suction drain, is placed in the incision, and the neck is wrapped with a pressure dressing at the end of the operation. On postoperative day 1, the dressing can be removed and the patient is usually sent home later that day, after tolerating an oral diet. Some patients are discharged home on the same day as the surgery.
Follow-up
Patients are usually seen in the office 2-3 weeks after the procedure to make sure that the wound is well healed and that no problems are encountered.
Complications
Complications from operating on a branchial cleft or thyroglossal duct anomaly include infection, hematoma, and recurrence.
Branchial cleft anomalies
Ideally, remove the cyst intact without entering the cystic cavity. Removing these lesions in a piecemeal manner increases the chance of leaving residual epithelial tissue and, therefore, increases the risk of recurrence. Take care also in obtaining meticulous intraoperative hemostasis.
Transient, and even permanent, injury to the facial nerve can be a complication of operating on first branchial cleft anomalies. The internal and external carotid arteries, internal jugular vein, and cranial nerves IX, X, XI, and XII all are at risk when dissecting second and third branchial cleft anomalies. The recurrent laryngeal nerve especially is at risk when dissecting along the tract of a third branchial cleft anomaly.
A retrospective study by Mattioni et al using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database found that at least one 30-day postoperative complication, predominantly superficial surgical site infection, occurred in 45 out of 895 patients (5.0%) who underwent pediatric branchial cleft cyst excision. The 30-day complication rate was higher in patients with a history of developmental delay. [12]
Similarly, a study by Moroco et al using the pediatric and adult NSQIP databases found postoperative complications associated with branchial cleft cyst excision to be relatively uncommon in adults and children. Complication rates of 3.9% and less than 1% were reported in children and adults, respectively, while readmission rates were 1.1% and 1.2%, respectively. The evidence also indicated that in adults, smoking status significantly impacts postoperative complications (odds ratio 6.25). [13]
Thyroglossal duct cysts
The greatest risk of recurrence of a thyroglossal duct cyst (TGDC) is associated with failure to follow the surgical principles described by Sistrunk. For example, a study by Danau et al indicated that in pediatric patients with TGDCs, there is less risk of recurrence in those treated with the Sistrunk operation than in individuals who undergo treatment with only simple excision or marsupialization. With recurrence found in 12 out of 104 cases (11.5%), five recurrences (41.7%) developed patients who had not undergone the Sistrunk procedure. [14]
Rates of recurrence are also increased when a TGDC is ruptured during dissection. Previous infection, prior incision and drainage procedures, and adherence of the cyst to the skin all are associated with an increased rate of rupture with dissection. Wound infections can also occur when the cyst is ruptured or when the pharynx is entered.
Outcome and Prognosis
With no history of infection or prior surgery, the recurrence rate after operating on a branchial cleft anomaly is approximately 3%. The recurrence rate increases to approximately 20% after prior unsuccessful attempts at surgical removal. The recurrence rate associated with simple excision of a thyroglossal duct cyst (TGDC) is approximately 50%. The recurrence rate with a formal Sistrunk procedure is approximately 5%.
Future and Controversies
Branchial cleft anomalies
The risk of malignancy arising from a branchial cleft cyst has been a topic of debate for years. Von Volkmann first described branchial cleft cyst carcinoma in 1882; however, the consensus today is that branchial cleft carcinoma rarely, if ever, occurs.
In 1950, Martin et al reviewed the literature and rejected all of the previous reports of branchial cleft cyst carcinoma. [15] They proposed that most of these patients had a metastatic squamous cell carcinoma cyst from an undiagnosed primary lesion. Before diagnosing a patient with a branchial cleft cystic carcinoma, the patient must meet the following criteria:
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The cystic tumor must be located along the line from anterior to the tragus, downward along the anterior border of the sternocleidomastoid muscle, to the clavicle.
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Histologic examination reveals cancer developing in the wall of an epithelial-lined cyst. Transition from benign cyst epithelium to squamous cell carcinoma along the wall of the cystic cavity is evident.
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The patient must have survived at least 5 years without developing any other lesions that could possibly be the primary tumor.
In 1979, Batsakis estimated that, even when including questionable cases of branchial cleft carcinoma, the incidence of branchial cleft carcinoma is approximately 0.3% of all malignant head and neck neoplasms. [16] On the other hand, metastatic cystic lymph nodes are quite common; therefore, patients with cystic carcinoma in the neck are assumed to have carcinoma metastatic to cervical lymph nodes from an unknown primary site.
Thyroglossal duct cysts
Literature regarding carcinoma arising from a thyroglossal duct cyst (TGDC) does not share the same controversy as reports of branchial cleft cyst carcinoma. In 1925, Ashurst and White first reported a case of carcinoma arising in a thyroglossal duct remnant. [17] Since that time, more than 100 cases have been reported, with the overall incidence of TGDC cancer being less than 1%. For unclear reasons, cancer in a TGDC is more common in females than in males. The diagnosis of carcinoma arising in a TGDC is usually made histologically only after the tumor has been removed.
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Axial CT scan of a patient with a relatively small thyroglossal duct cyst.
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Axial CT scan of a first branchial cleft cyst.
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Axial CT scan of a second branchial cleft cyst.
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Axial CT scan of a third branchial cleft cyst.
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Preoperative photograph of a 20-year-old female who underwent a simple excision of a thyroglossal duct cyst 12 years ago in Europe. The patient has had multiple infections over the past 10 years. The patient was actively infected at the time of this photograph, as seen by the skin erythema and swelling.
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CT scan showing an infected recurrent thyroglossal cyst 12 years after simple excision.
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Surgical specimen from the patient in Image 5 with prior simple excision of a thyroglossal duct cyst. Fistula tract with surrounding skin, cyst, midportion of the hyoid bone (which was not removed on prior surgery), and cuff of the base of the tongue muscle were excised.
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Preoperative photograph of a man with a recurrent infected thyroglossal duct cyst.
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Axial CT scan of the man in Image 8 with an infected thyroglossal duct cyst.
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Intraoperative picture of the patient in Image 8 undergoing a Sistrunk procedure. The central portion of the hyoid bone is being resected along with the cyst, overlying skin, and cuff of the base of the tongue muscle.
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Postoperative picture of the patient in Image 8 after a successful Sistrunk procedure.
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CT scan of a man with a large neck lymphangioma.
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Intraoperative picture of the resection of a large cystic lymphangioma.
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Resection specimen of a well-circumscribed lymphangioma that was able to be removed in its entirety without sacrificing any surrounding structures.
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Second branchial cleft fistula.
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First branchial cleft cyst.
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Thyroglossal duct cyst.
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Picture of a 5-year-old-boy one year after having a Sistrunk procedure to remove a thyroglossal duct cyst.