A choledochal cyst (dilatation of the bile duct)
A choledochal cyst is a swelling/widening or dilatation of the bile ducts. The condition usually affects the part of the bile ducts outside the liver (the common bile duct and the hepatic ducts) but sometimes it also affects those inside the liver (the intrahepatic ducts)Choledochal Cyst in Children. The exact cause of a choledochal cyst remains unknown but there are a few theories. One explanation that it happens due to the bile duct not forming properly. when the baby developing in the womb in early pregnancy.
This concept is supported by the fact that in some cases. The cyst is first seen during a routine ante-natal ultrasound scan of the baby in early pregnancy. Another theory that the junction of the bile duct. The pancreatic duct not normal and forms an abnormally long ‘common channel’. Currently, there are arguments in support of both of these.
DIAGNOSIS OF CHOLEDOCHAL CYST:
The diagnosis is generally made using a combination of the following:
A physical exam of the child.
Tests including blood tests and an ultrasound scan. A choledochal cyst most often suspected. if an abdominal ultrasound scan shows a dilated bile duct in a baby. a child with jaundice or if the child has abdominal pain. Once suspected some other tests are required to get more information. For example, there any blockage in the duct by a stone, or there an abnormal junction of the bile duct with the pancreatic duct (a long common channel)? These extra tests carried out to get more information. About the type of choledochal cyst present which helps the surgeon to get a ‘road map’ also to plan the operation. These tests may include:
A detailed ultrasound scan to look not only at the bile ducts but also to look at the blood vessels going to the liver which run alongside the bile ducts.
MRCP (Magnetic Resonance Cholangio-Pancreatography).
This type of detailed scan is carried out in a large machine. It does not require X-rays but the patient does need to lie flat and still. And so babies and small children often require a general anesthetic. The bile ducts and the pancreatic duct, are shown better on an MRI scan.
This is a specialized procedure that not often needed. It is done under a general anesthetic. In this procedure and a flexible tube with a small camera on the end (an endoscope) passed through the mouth down into the intestine. A tiny plastic tube then passed through this endoscope into the opening of the bile duct, and dye injected to outline the choledochal cyst and the pancreatic duct.
This helps to give information about the junction of the bile duct. With the pancreatic duct (long common channel) and if there any blockage in the bile duct due to stones etc. This investigation can sometimes stir up inflammation in the pancreas (pancreatitis) causing temporary abdominal pain and vomiting afterward. It is rarely done as it is an invasive investigation.
Rarely a HIDA (liver scan)
Rarely a HIDA becomes necessary. if there is only a single cyst in the liver and the MRCP cannot confirm it to a choledochal cyst/anomaly. The exact nature of the choledochal cyst sometimes only becomes clear at the time of surgery. when the dye injected into the bile duct system (an operative cholangiogram).
TREATMENT FOR CHOLEDOCHAL CYST:
The treatment of choledochal cysts is surgery. This should be done in a center that experiences looking after children. who have choledochal cysts and surgeons experienced with this kind of operation? In the common variety. The cyst completely removed. This means removing most of the bile ducts (tubes carrying bile) outside the liver together with the gallbladder Choledochal Cyst in Children. The hepatic ducts (tubes from the liver) coming out of the liver. then attached to a loop of the child’s bowel. So that the bile can drain into the bowel. This loop of the bowel is a specially created loop.
-More about treatment:
Removing the gallbladder has no important long-term effects that we know of. A liver biopsy may also be taken at the time of surgery to seeing. if the liver healthy or damaged. In babies with a cyst discovered by ultrasound scan. But who has no symptoms? There debate about the best time to perform surgery on Choledochal Cyst in Children. Children’s surgeons who specialize in liver and bile duct surgery often recommend early surgery. generally at about six months of age.