Choledochal Cysts | Overview
What is a choledochal cyst?
A choledochal cyst is a congenital anomaly of the duct (tube) that transports bile from the liver to the gall bladder and small intestine. The liver produces bile to help digest food. When a child has a choledochal cyst, a swelling of that duct, bile may back up in the liver. This can cause liver problems or inflammation of the pancreas (pancreatitis) because it blocks the main duct from the pancreas gland to the intestine. Children with choledochal cysts have a higher rate of cancer of the bile duct in adulthood. Early treatment can reduce these risks.
Choledochal cysts are rare: one in every 100,000 to 150,000 children in Western countries is born with choledochal cysts. Girls are four times more likely to be affected than boys. The condition is more common in East Asian countries, especially Japan, though researchers do not know why.
Choledochal cysts are congenital.
What are the symptoms of a choledochal cyst?
Although children are born with choledochal cysts, symptoms may appear in infancy or not for several years. The following symptoms may occur in infants or older children:
What causes choledochal cysts?
The bile duct transports bile from the liver, through the pancreas, to the first part of the small intestine (the duodenum). Researchers believe that choledochal cysts form when there is an abnormality at the intersection between the bile duct and pancreatic duct. This abnormal connection forces pancreatic juice to flow backward into the bile duct and may cause cysts to form.
Types and locations of choledochal cysts
Choledochal cysts can form in the part of the bile duct inside of the liver (intrahepatic) or outside the liver (extrahepatic).
There are four basic types of choledochal cysts based on where they appear:
- Type 1 — a cyst of the extrahepatic bile duct, accounting for up to 90% of all choledochal cysts
- Type 2 — an abnormal pouch or sac opening from the duct
- Type 3 — a cyst inside the wall of the duodenum
- Type 4 — cysts on both the intrahepatic and extrahepatic bile ducts
What is the liver, and what does it do?
The liver is the second largest organ in the body, located in the abdominal cavity, beneath the diaphragm and above the stomach and intestines.
In addition to producing bile that helps the intestines digest food, the liver helps the body in many ways:
- produces proteins that allow blood to clot normally, transport oxygen, and support the immune system
- stores extra nutrients
- helps clean the bloodstream of harmful substances
- helps control blood sugar and cholesterol levels
Our areas of innovation for choledochal cysts
Minimally invasive surgery (MIS) is done through small incisions using miniaturized surgical tools and cameras or telescopes. MIS usually results in less pain, less scarring, and a quicker recovery time.
One form of MIS used to remove choledochal cysts is called laparoscopic surgery, during which surgeons use small instruments guided by a small telescope. The instruments are manipulated by the surgeon who controls their movements, while watching them on a video screen.
Choledochal Cysts | Diagnosis and Treatment
How are choledochal cysts diagnosed?
Some choledochal cysts are detected on an ultrasound before a child is born.
Sometimes after a baby is born, the child's parent or doctor may notice a mass in the upper right abdomen.
A combination of tests help doctors verify that a child has choledochal cysts:
- Computerized tomography scan (CT or CAT scan) — A CT scan shows detailed images of any part of the biliary system.
- Cholangiography — a radiographic visualization of a child’s bile duct
How are choledochal cysts treated?
Children with choledochal cysts need surgery to remove them. This involves removing a lobe of the liver if the cysts are intrahepatic, or part of the duct outside of the liver if the cysts are located there. This surgery also includes biliary reconstruction using a piece of intestine.
Minimally invasive surgery
Surgeon are often able to remove choledochal cysts with a minimally invasive surgery called a laparoscopy. With this technique, small instruments guided by a small telescope are passed through the body.
In many cases children, can go home in one to two days and return to their normal activities more quickly than children who have open surgery.
Other benefits of minimally invasive surgery include:
- very small scars, which are difficult to see after several months
- less pain after surgery
- usually a shorter hospital stay
Without surgery, children with choledochal cysts have an ongoing risk of other problems:
In adulthood, choledochal cysts can become cancerous if left untreated.