Neck cyst is a hollow pathological formation that is located in the neck area and contains a liquid or mushy mass. It belongs to the number of congenital pathologies, it can be lateral or median. Lateral cysts are detected immediately after birth, median cysts can be detected as the child grows or become a random find in the course of any medical research. Possible complications are suppuration, fistula formation and malignant degeneration. In most cases, neck cysts are subject to surgical removal. Cyst punctures are ineffective, because later the contents accumulate in its cavity again. There is no conservative treatment.
Neck cyst is a hollow tumor–like formation located on the anterior or lateral surface of the neck. It is formed with disorders in the early stages of embryonic development. In some cases, it is combined with a congenital fistula of the neck. Sometimes a fistula is formed already in childhood or even adulthood as a result of suppuration of the cyst. Possible degeneration of the neck cyst into a malignant tumor. Treatment is only surgical.
Lateral neck cysts are usually detected at birth, median cysts are detected at the age of 4-7 or 10-14 years, sometimes they are asymptomatic. In one of 9-10 patients, a lateral cyst is observed in combination with a congenital neck fistula. In about 50% of cases, cysts are suppressed, and a fistula is formed as a result of emptying the abscess through the skin.
The lateral cyst of the neck is a cavity between the gill furrows, which normally should disappear as the fetus develops. It is formed with an anomaly of the development of the gill slits in the fourth to sixth weeks of pregnancy. The median cyst is formed when the rudiment of the thyroid gland is moved from the place of its formation to the anterior surface of the neck along the thyroid-lingual duct. This happens in the sixth to seventh weeks of pregnancy.
Congenital fistula is not an independent pathology and is always combined with a lateral or median cyst of the neck. There are two types of fistulas: complete (with two exit holes: on the skin and oral mucosa) and incomplete (with one hole, which can be located both on the skin and on the mucous membrane).
Lateral neck cysts
Lateral neck cysts are more common than median cysts (in about 60% of cases). They are located on the antero-lateral surface of the neck, in its upper or middle third, anteriorly from the nodding muscle and are localized directly on the neurovascular bundle, next to the internal jugular vein. There are both multi-chamber and single-chamber. Large lateral neck cysts can squeeze vessels, nerves and nearby organs.
In the absence of suppuration or compression of the neurovascular bundle, there are no complaints. During the examination, a rounded or oval tumor-like formation is revealed, especially noticeable when the patient’s head is turned in the opposite direction. Palpation is painless. The cyst has an elastic consistency, is mobile, not soldered to the skin, the skin above it is not changed. As a rule, fluctuation is determined, indicating the presence of fluid in the cyst cavity. During puncture, a cloudy liquid of a dirty-white color is found in the cavity of the formation.
With suppuration, the cyst of the neck increases in size, becomes painful. The skin above it turns red, local edema is detected. Subsequently, a fistula is formed. When opened on the skin, the mouth of the fistula is located in the area of the anterior edge of the nodding muscle. When opening on the oral mucosa, the mouth is located in the area of the upper pole of the palatine tonsil. The hole can be either point-shaped or wide. The skin around the mouth is often covered with crusts. Maceration of the skin and hyperpigmentation are observed.
The diagnosis of a lateral cyst of the neck is made on the basis of anamnesis and the clinical picture of the disease. To confirm the diagnosis, a puncture is performed followed by a cytological examination of the resulting fluid. Additional research methods such as ultrasound, probing and fistulography with an X-ray contrast agent can be used.
With an uninfected neck cyst, differential diagnosis is performed with lymphogranulomatosis and non-organ neck tumors (lipoma, neurinoma, etc.). A suppurated cyst is differentiated from adenophlegmon and lymphadenitis.
Median neck cysts
Median cysts in traumatology account for about 40% of all neck cysts and are located on the front surface of the neck, along the midline. Upon examination, a dense, painless, clearly delimited formation of elastic consistency with a diameter of up to 2 cm, not soldered to the skin, is revealed. The cyst is slightly mobile, soldered to the body of the hyoid bone, shifts when swallowing. In some cases, the tumor-like formation is located in the root of the tongue. At the same time, the tongue is raised, speech and swallowing disorders are possible.
Median cysts are more frequent than lateral cysts – in about 60% of cases. When infected, the formation increases in size, becomes painful. The surrounding tissues swell, the skin turns red. When the abscess is opened, a fistula is formed with the mouth located on the front surface of the neck, between the thyroid cartilage and the hyoid bone. If the fistula opens into the oral cavity, its mouth is located on the front surface of the tongue, on the border between its root and the body.
The diagnosis of a median cyst is made on the basis of anamnesis and clinical data. Ultrasound and cyst puncture with subsequent cytological examination are used as methods of instrumental diagnostics. During puncture, a viscous cloudy yellowish liquid containing lymphoid elements and cells of a multilayer flat epithelium is obtained. Fistulography and probing are used to study fistulous passages.
The median cyst of the neck is differentiated from the struma of the tongue, dermoid cyst, lymphadenitis, specific inflammatory processes and adenoma of an abnormally located thyroid gland.
Treatment of neck cysts is only operative. The volume of the operation is determined by the patient’s condition, the presence and type of complications. In elderly patients with severe concomitant diseases, aspiration of the cyst contents is performed, followed by washing of its cavity with antiseptic drugs. In other cases, this method is not used due to insufficient effectiveness and a high risk of relapse.
- Uncomplicated cysts. Surgical removal of the neck cyst is indicated for all lateral cysts, median cysts of any size in childhood and median cysts with a diameter of more than 1 cm in adults. To prevent relapses, the cyst is excised together with the capsule. During surgical interventions for the median cyst, a part of the hyoid bone is also removed, through which the weight from the tumor-like formation passes. During operations for a lateral cyst, difficulties may occur due to nearby vessels and nerves. Depending on the size, the cyst of the tongue root can be removed both through an incision on the skin and through the mouth.
- Suppurated cysts. With suppuration of the cyst, its complete removal is not shown. Autopsy and drainage are performed. An indication for an emergency operation is the presence of an acute inflammatory process, especially when the fistula is closed and an abscess is formed. Subsequently, regular bandages are carried out with washing of the cyst cavity with antiseptic drugs, anti-inflammatory therapy is prescribed. Sometimes the cyst cavity is scarred. If this does not happen, its removal is carried out no earlier than 2-3 months after the elimination of inflammation.
- Cysts with fistulas. The median and lateral fistulas of the neck must be excised and removed. This task can be fraught with a number of difficulties due to the thin wall and tortuous passages of the fistula. Therefore, before the operation, a probe or a staining drug (diamond green, methylene blue) is injected into the fistula passage. During the operation, all fistula passages are removed, including thin and inconspicuous ones, otherwise a relapse is possible. The operation of excision of the lateral fistula of the neck is particularly difficult, since in this case the fistula passes between the internal and external carotid arteries.