A cyst is a sac or pouch that contains liquid or semi-solid material and a sinus is a small opening. They are found on the head and neck and these are mostly residual structures from embryologic development that have not matured or have not been reabsorbed. Sometimes, lumps may also develop due to inflammation, infection or tumours that affect the lymph nodes in the neck area.
Branchial arches are structures that develop in the fourth week of development of embryo. They develop on either side of the head and neck and paired outpouchings from the inner lining of the early part of mouth and throat. Clefts too develop, along with muscles, nerve structures and connective tissues of the neck area. Continued development results in the formation of ear canal, tonsil, throat structures and parathyroid glands. Totally there are four distinct clefts and incomplete development of any of these gives rise to abnormalities.
Abnormalities of the first brachial left cleft result in cysts or sinus behind the parotid gland and do not cause symptoms until adulthood. Problems of the second cleft are more common and are usually found in the mid or lower neck. They form lumps and are not related to sinus. Surgical removal may be required. Cysts and sinuses of the third cleft, though not common, occur in the same areas as the second, but have a different path. Problems with the fourth cleft are rare and may be present in the lower part of the neck, usually on the left side and may be due to infection of the thyroid gland.
All branchial sinuses should be excised as early as six months owing to the fact that repeated infection is common, that makes resection at a later stage, difficult. All the cysts should be drained before surgery. The surgery, done on an outpatient basis, is performed under general anesthesia involves complete removal of cysts. Bandages can be removed within 7 days after surgery. Surgery yields good results.
A thyroglossal duct cyst, found halfway down the front of the neck that is generally single, feels like a firm lump and moves upward when one swallows. Sometimes, the cyst becomes enlarged and infected, causing pain and tenderness. This condition requires the removal of thyroglossal duct cyst. The surgical procedure, that may take 2 hours, involves administering general anaesthesia to the child undergoing surgery. The surgeon makes an incision in the child’s neck and takes out the cyst. He may also let a tube in, to drain out the extra fluid. He then closes the cuts with stitches.
Preauricular pits, sinuses and cysts are not related to branchial cleft development, but are found at the front of the upper part of the ear. These pits are lined by skin cells and may swell if a cyst is present. If they get infected, the cysts have to be drained and subsequently removed.
Dermoid and inclusion cysts are due to the burial of skin pieces under the skin surface where bones and skin join together. These dermoid cysts are most commonly found in the head, neck near the collar bones, middle of skull and midline from the tip of the nose along the head to the spine. Surgical intervention is required to remove these cysts.
Cervical thymic cysts arise from the thymus gland in the chest and are soft swellings in the back of the neck and are excised with a low back incision. However, if they have extended to the chest, the upper part of the breast bone has to be opened to completely remove the cyst.