Cervical Cysts, Sinuses, and other Neck Lesions

Cysts (fluid filled lumps), solid lumps, and sinuses (small openings) found about the head and neck are frequently residual structures from embryologic development that have failed to resorb completely or mature. Some lumps may be caused by inflammation, infection or even tumors affecting lymph nodes in the neck area.

CYSTIC HYGROMA (lymphangioma)
Cystic hygromas are varying sized cystic abnormalities of the lymphatic system occurring in perhaps 1 in 10,000 births. The word is derived from the Greek meaning moist or watery tumor and can occur equally in boys and girls. Approximately 50 or 60 percent are present at birth and about 80-90 percent appear or are detected before the end of the second year of life.

Embryology: Their cause is related to lymph channel development of the lymphatic system and may be due to poor communication with developing veins, which result in isolated sacs or little blind ends. These sacs slowly enlarge (filled with fluid) and may seem to infiltrate into surrounding tissues or push other tissues aside.

Figure 1. Characteristic large neck cystic hygroma present since birth in 3-month-old boy

Cystic hygromas present generally as a multicystic mass with thin walls, and being fragile they may have areas of bleeding or accumulation of blood within them. They usually reside in close association with large veins and known lymphatic ducts in the neck, axillary area, groin area, or may infiltrate any areas of the skin along the trunk, extremities, or inside the chest or abdomen (Figure 1).

They present as soft, discrete, and nontender swellings that are often compressible. Cysts within the mass vary from a very small size of a few millimeters to one of several centimeters. In some cases the hygroma may involve two or more areas by direct extension and seem to occur on the left side of the neck twice as often as the right, possibly related to the development of a large lymphatic structure in the chest which empties into the left internal jugular vein (Figure 2).

Most are noted shortly after birth and seem to gradually enlarge as they fill. They may expand as a result of bleeding into them or infection, in which case they may become tender or hurt and the overlying skin will have an inflamed or red appearance. It is common for a bluish color to appear under the skin, even though the liquid is clear, and the color of ginger-ale. In the neck the cysts can extend downward into the chest and on rare occasion may produce breathing difficulty because of pressure on the airway or difficulty with swallowing with resultant failure of the child to grow because of his or her inability to eat without discomfort.

Infection in a cystic hygroma may cause rapid enlargement and pain and respond slowly to antibiotic therapy. When this occurs, there is some scarring in the cystic hygroma, as well as the tissue adjacent to it, which may complicate surgical therapy. Although usually recognizable by physical examination alone, sometimes the use of imaging studies, such as ultrasonography and computed tomography (CAT scan), are helpful in distinguishing cystic hygromas from solid masses.

TREATMENT
Cystic hygromas rarely go away on their own. Aspiration by puncturing with a needle is usually followed by prompt reaccumulation of fluid or development of infection. Injection of chemical agents to cause shrinkage is effective in certain hygromas where there are large cysts, but is not as effective when there are very small cysts. This is not without potential complications, and as yet there is no universal agent available that is totally safe.

When infection occurs, it is necessary for the child to be treated with antibiotics, yet definitive treatment may rest in surgical removal once the infection is controlled. Most pediatric surgeons defer surgery until approximately six months of age if the rate of enlargement does not exceed general body growth. Complete removal is challenging and reoccurrence may be 5 or 10 percent, even in favorable cases. Although all efforts are made to remove remnants of the cyst, because it is non-cancerous no major nerves or other important structures should be removed when removing the cysts.

BRANCHIAL CYSTS, SINUSES AND REMNANTS
Embryology : Branchial arches are structures that appear in the fourth week of development on either side of the head and neck. Paired outpouchings from the inner lining of the early part of the mouth and throat along with clefts (inward indentations) appear along with muscular, nervous structures, and connective tissue in the neck area. Continued development in this area, from the outpouchings and from the clefts results in the ear canal, tonsil, throat structures, parathyroid glands and thymus. There are four distinct clefts, each giving rise to abnormalities if incomplete development occurs or there is a failure of these primitive structures to go away.

Of the branchial cleft anomalies, 75 percent arise from the second cleft, 20 percent from the first, and a few remaining from the third and fourth clefts (Figure 3).

Cysts (fluid-filled structures) developing from these structures usually present later in childhood than do sinuses (small openings that end blindly or attach to a cyst), while left over pieces of cartilage are usually found in infancy or at birth. A complete communication between the inside of the throat and outside of the skin is called a fistula. Fistulas from the second and third pouches exit the skin just in front of the large muscle in the neck, the sternocleidomastoid muscle. Mucus may be noted to come from a small opening and a fistula from here may go up through the neck until it ends in the region of the tonsil. These fistulas may be on both sides in 10-15 percent of the cases.

Any combination of sinus tract with cyst (small connection which connects with the skin on one end and the cyst on the other) or without cyst (blind ending connection) can occur between any location from the throat to the skin.

Abnormalities of the first branchial cleft present as a cyst or sinus lying behind the parotid gland, which is located at the back of the jaw in the neck and may not cause symptoms until adulthood. Left over cartilage from the second branchial arch are more common than those of the first and are usually found in the mid or lower neck. They may be attached to the skin, just under the skin, or in the muscle, and usually do not have a sinus with them. Appropriate treatment is surgical removal.

Cysts and sinuses from the third branchial cleft are uncommon. They occur in the same area as the second, but may enter the throat through a different course. Those of the fourth branchial cleft are rare and may present as abscesses in the lower part of the neck, on the left side usually more than the right, and may be associated with infection of the thyroid gland. Surgical removal may involve removal of the upper pole of the thyroid gland along with the connection that goes into the throat just to the side of the larynx, or voicebox, in what is called the pyriform sinus.

DIAGNOSIS
The diagnosis of sinuses is based on visually seeing it and recognizing it. Clear mucus material may drain intermittently and can be expressed by pressing on the area. Blind-ending sinus tracts may appear as mere dimples in the skin and may be associated with a small piece of extra cartilage material. Cysts may not have an external opening. Such cysts often present in older infants and children as a mass, which may feel very much like a solid tumor and are distinguished by ultrasound showing a fluid-filled cystic mass, rather than a solid mass.

TREATMENT
Almost all branchial sinuses should be excised early in life (age 6 months), as repeated infection is common resulting in scarring that makes resection later more difficult. When infection does occur, antibiotic administration and, if necessary, incision with drainage of the cyst should occur before definitive surgery.

PREAURICULAR PITS, SINUSES AND CYSTS
Frequently there are small pits at the front of the upper part of the ear, which are unrelated to branchial cleft development, but do represent abnormal development of the outer ear. These pits are lined by skin cells and may contain hair and local swelling if a cyst is present. These pits often run in the family. They usually do not cause symptoms and removal is not routinely needed. However, when drainage from or infection of a cyst occurs, drainage of pus from an abscess may be needed and subsequent removal of the pit and cyst carried out.

DERMOID AND INCLUSION CYSTS
Where bones and skin join together during development, pieces of skin may become buried beneath the skin surface leading to the formation of cysts. These are called dermoid cysts because they contain material that is skin-like. The most common location in the head and neck is along the outer part of the eyebrow. They can also occur in the middle of the neck near the collar bones. Other common areas in the skull are where pieces of the skull bones fuse together and also right down the middle or midline of the skull. Cysts that occur in the midline from the tip of the nose along the head to the spine in the back may have connections to the brain and CT scans or MRIs are required before their removal.

THYROGLOSSAL DUCT CYSTS AND SINUSES

Embryology: The thyroid gland, although situated in the lower portion of the neck around the trachea, originates in the mouth at the back of the tongue and then moves down the neck during development. As the thyroid gland moves down to its normal position, there is a connection to the base of the tongue that should disappear by the time the thyroid reaches its final position. If it does not, there may be a persistent hollow tube that may allow accumulation of mucoid material and the formation of a cyst at the end (Figure 4).

This is known as a thyroglossal duct cyst. Frequently this is noted soon after a cold when there has been swelling of the tonsils and other lymphoid tissue of the throat.

DIAGNOSIS
Approximately three-fourths of thyroglossal duct abnormalities present as cysts, whereas 25 percent present as a draining sinus on the skin. A sinus occurs as a result of infection (in the cyst) and rupture onto the skin with persistent drainage. The cysts are generally asymptomatic and are noticed by the family as a soft swelling under the chin over the area of the hyoid bone, a floating bone in the upper neck to which the tongue muscles are partially attached.

Thyroglossal cysts are usually single, smooth, and usually 1-3 cm in size and move when the patient swallows or protrudes the tongue. The other causes for masses in this area of the neck include abnormally located thyroid tissue, lymph nodes, and dermoid cysts. X-rays are not usually needed, as the diagnosis is frequently made by examining the mass. Thyroid scanning is not generally necessary, but is reserved for patients who have either no detectable thyroid tissue in the neck on examination or who following surgery have thyroid tissue noted within the surgical specimen. The tissue in this abnormal location is best removed, and if no other thyroid tissue is identified the patient requires lifelong thyroid hormone replacement therapy.

TREATMENT
The treatment of choice for thyroglossal duct cyst is complete removal of the cyst along with the extension to the back of the tongue. This is done in conjunction with removal of the central portion of the hyoid bone and is known as the Sistrunk procedure, named for the man who described it in 1920. Delay in treatment often results in another infection, which necessitates antibiotic therapy and delay of surgery until all the infection and inflammation are resolved.

Removal is carried out generally as an outpatient under general anesthesia.

Approximately 10 percent of the cysts come back and are usually treated by a second removal. Reoccurrences are more common in patients who have had infected or previously drained thyroglossal duct cysts. Cancer has been reported in a small number of patients in whom the cyst was not removed until adulthood. Although rare, multiple recurrences have also been reported, usually requiring wider removal of tissue in the region of the remaining hyoid bone.

RANULA
Ranulas are soft fluid-filled masses in the floor of the mouth related to blocked openings of the small salivary glands under the tongue. They may be on either side or both sides under the tongue and may be found as large swellings in the mouth or on the undersurface of the chin. Surgical treatment involves unroofing the cyst without complete removal, allowing drainage of the cyst fluid into the mouth.

CERVICAL THYMIC CYST
Cysts arising from the thymus gland in the chest may present as soft swellings in the lower part of the neck. They can be mistaken for cystic hygromas, branchial cleft cysts, or even low-lying thyroglossal duct cysts. Thymic cysts generally can be excised through a low neck incision. When there is extension into the chest, the upper part of the breast bone may need to be opened for adequate removal.

TORTICOLLIS
Torticollis, or wry neck, results from scarring and a mass in the middle portion of the large muscle in the neck known as the sternocleidomastoid muscle (Figure 5).

The cause is unclear and appears to be higher in patients who are in breech presentation at birth. The mass is tumor-like and has been called a pseudotumor, although there is nothing to suggest it is anything but scarring of the muscle. In most infants the mass is noted between two and eight weeks of age. A firm lump is felt and the position of the face may be turned away from the mass and tilted upward. Extensive x-ray studies are generally not needed, although ultrasonography will demonstrate the mass and the diagnosis without subjecting the child to unneeded radiation. Torticollis or a solid neck mass in an older child demands careful evaluation and more tests for a tumor or other neck spine abnormalities.

TREATMENT
In most infants, operative treatment is NOT necessary. Passive stretching of the neck is recommended. Proper positioning of the patient to encourage them looking towards the side of the mass during feeding or when positioned in a room may add to successful therapy. Massage may be of some benefit, but early range of motion stretching is often helpful. Criteria for operation is poor growth of one side of the face/head, which may result in permanent disfigurement. The overwhelming majority of patients, however, do not require surgery.

When operative treatment is indicated, it involves cutting across the connective tissue at the base of the neck, as well as the sternocleidomastoid muscle, so as to release the tension and allow the head to return to a normal position. Postoperatively, intensive physical therapy to promote full rotation of the neck in both directions is started as soon as is feasible.

CERVICAL LYMPHADENOPATHY
Anterior cervical lymph nodes drain into the mouth and pharynx, so almost all upper respiratory infections have some effect on these lymph nodes causing swelling and tenderness. Lymph nodes are palpable in 80-90 percent of children 4-8 years old. They are uncommon to be felt in infants unless lingering infection occurs or there is a tumor process.

SUPPURATIVE CERVICAL LYMPHADENITIS
The function of lymph nodes is, effectively, to act as filters or traps for bacteria or viruses that have invaded into the body and, as such, are one of the first lines of the immune defense for the body. When lymph nodes are involved in fighting the infection or foreign material, they swell, and when bacteria are involved, may become filled with pus or develop an abscess. Nodes that continue to enlarge and are quite firm may be involved in a tumor process.

The most frequent cause of infected neck lymph nodes is infection of the throat and tonsils with either the streptococcal or staphylococcal germ. Typically, rapid enlargement of one or more neck lymph nodes occurs with tenderness, swelling, and redness of the surrounding area. Fever and elevation of the white blood cell count are common. Without treatment the lymph node usually continues to enlarge and becomes involved with the overlying skin. Spontaneous rupture or drainage of the pus often follows.

When lymph nodes are swollen on both sides of the neck, a viral infection is generally the cause and usually goes away within a few weeks. Enlarged lymph nodes that are present for longer than 4-6 weeks and are hard may indicate a tumor process.

Early antibiotics may prevent the formation of abscess. When softening of the lymph node occurs, drainage by an incision is generally necessary, although removing the pus by a needle combined with antibiotic therapy may be sufficient. When drainage is done surgically, the wound is left open and packed until the process totally resolves.

MYCOBACTERIAL LYMPHADENITIS
Persistent unilateral enlargement of nodes on one side of the neck, which look infected but don’t respond to the usual antibiotic therapy, may indicate mycobacterial infection. Mycobacteria are a group of bacteria including those of tuberculosis. Lymphadenitis caused by mycobacterial tuberculosis is considered an extension of lung infection and most commonly is in the lymph nodes just above the collar bone at the base of the neck. When mycobacterial tuberculosis infection is confirmed by a skin test, family history, or evidence of lung disease, antituberculous drugs are likely to make them better within several months.

When atypical mycobacteria infection that is not tuberculosis is identified, complete surgical removal of the involved lymph nodes is generally required, as standard antituberculous treatment appears to be of little value.

CAT SCRATCH DISEASE
Cat scratch disease is one of the more common causes of nonbacterial lymph node enlargement in the neck and other areas of the body. A likely cause seems to be a small germ known as Bartonella henselae. A scratch from a kitten usually causes the disease. The kitten or cat is not sick and the scratch is often not recognized.

The disease starts with a little pimple at the site of the scratch followed by enlargement of the lymph nodes in the area within two weeks. However, node enlargement may not occur for many weeks later, long after the scratch has occurred. Lymph node enlargement in the armpit area occurs in more than 60 percent of the patients, although lymph nodes may be involved in the neck, in front of the ear, under the jaw, or above the elbow. Diagnosis is frequently one of recognition based on a good story. At present there is no specific therapy for cat scratch disease. It is generally mild and goes away on its own. Treatment with Clarithromycin may offer some benefit.

Diagnosis may be confirmed by identification of cat scratch genes from some of the pus, however this is generally not needed. Rarely, patients may feel sick or have a headache, vomiting, and low-grade fever. Surgical removal is not indicated if only lymphadenopathy or lymph node swelling is present and resolves over 4 to 6 weeks. When the lymph node becomes filled with pus, surgical drainage is warranted. Enlarged lymph nodes which persist may indicate tumor and then biopsy is indicated.

Articles and graphics adapted from O'Neill: Principles of Pediatric Surgery. © 2003, Elsevier.