What Is A Branchial Cleft?

Medically Reviewed by Dan Brennan, MD on May 23, 2023
Written by WebMD Editorial Contributors
4 min read

A branchial cleft is also called a cleft sinus. It is a lump or cyst that develops in your neck or near your collarbone. It develops in the womb before birth and is usually diagnosed shortly after birth.

A branchial cleft is when the tissue in your neck doesn’t develop correctly. The abnormal formation may have open spaces that allow pockets of fluid to drain from your sinuses and build up. This can occur inside or outside the neck.

The malformation is not usually painful, although it may be if the area becomes infected. If you suffer from a branchial cleft, you may be more likely to get infections in your neck and throat.‌

There are two types of branchial cleft abnormalities. The first is an internal cyst that forms a pocket inside your neck. It may appear as a large lump that protrudes out of the skin.

The second is a fistula that forms with an opening on your neck and drains on your skin’s surface. Fistulas usually form on top of the large muscles on one side of the neck. They do not usually form on both sides of the neck.‌‌

A branchial cleft can cause infections in the area that keep coming back. This may happen when you have another infection, like a cold, cough, or sore throat.

A branchial cleft is a birth defec‌t, meaning that it happens in the womb when a baby is growing. It happens when the area does not develop like it should when the baby is in the early stages of growth.

If your baby is born with a branchial cleft abnormality, the obvious signs include having a small lump or opening on one side of their neck at birth. Other sinus-related symptoms may be similar to other health conditions.

If your doctor notices any branchial cleft signs or symptoms, your baby may need additional tests for an exact diagnosis. In some cases, the lump isn’t large enough to be noticeable at birth. If there are no other symptoms, your child may not receive a diagnosis until later in their childhood.‌

The branchial cleft can become infected. The area may be infected if it is:

  • Red around the affected area
  • Warm to the touch
  • Swollen
  • Painful 
  • Draining mucus or other liquid‌

Your child’s pediatrician will ask you about their current symptoms during a physical exam. The doctor may feel your child’s neck for any inconsistencies in what is considered normal development.

Tests for diagnosing a branchial cleft include:

  • An ultrasound may show abnormalities under the skin
  • A MRI or computed tomography (CT) scan helps determine the exact location and size of the growth. Your child's doctor may inject dye into the area to make the growth more visible on imaging. ‌
  • Your child's doctor may take a biopsy of the tissue to ensure it isn’t a cancerous or precancerous growth. This rules out other health conditions.‌

Treating a branchial cleft. If the condition isn’t severe, your doctor may want to leave it alone and monitor it over time. Keep in mind that it will not heal or go away on its own without treatment.

If it causes health issues or impacts your child's quality of life, your doctor takes into consideration your child’s:

  • Age
  • Symptoms
  • Severity and placement of the growth‌
  • Other health conditions‌

Antibiotics treat an infection, but your child's doctor may cut and drain the area near the branchial cleft first. This gives the malformation a better chance of healing from the infection. If your child gets constant or recurring infections, surgery may be necessary to remove the tissue and prevent additional damage.

Surgery is used to remove a malformation or close an opening caused by a branchial cleft. An endoscopic treatment may be available for less serious cases. This type of surgery uses a small light and camera, doesn’t require an incision for repair, and offers an easier recovery.

In more severe cases, a surgeon needs to cut an opening in the skin to remove the tract and the growth. The doctor may remove a portion of the thyroid gland if it is affected by the growth. Following the surgery, your child may have a small tube in place that allows liquid to drain out as the opening heals. This is important since the area is already prone to fluid buildup and infection.‌

Your child may stay overnight for monitoring following the surgery and go home the next day. A follow-up appointment may include additional imaging tests to ensure the mass was completely removed and the area healed correctly. Once a branchial cleft is removed or repaired, it doesn’t usually return.‌

Branchial cleft malformations are usually small enough that they don’t have a significant health impact. However, if the mass is large enough, it may block your child's airways. This can lead to difficulty breathing and swallowing.

Because the growths are near other vital structures, in rare cases, a branchial cleft poses severe health risks to your child's: