In radiology, the double bubble sign is a feature of pediatric imaging seen on radiographs or prenatal ultrasound in which two air filled bubbles are seen in the abdomen, representing two discontiguous loops of bowel in a proximal, or 'high,' small bowel obstruction. The finding is typically pathologic, and implies either duodenal atresia, duodenal web, annular pancreas, and on occasion midgut volvulus, a distinction that requires close clinical correlation and, in most cases, surgical intervention. [1] [2] [3]
Distal gas is more often seen with midgut volvulus, duodenal stenosis and duodenal web, though this not always present. In such cases, distinguishing the diagnoses depends on clinical presentation. [4]
A fluoroscopic study known as an upper gastrointestinal series is often the next step in management in patients that are not critically ill, though if volvulus is suspected, emergent surgical intervention is mandated. If clinical findings are equivocal, caution with non water-soluble contrast is needed, as the usage of barium can impede surgical revision and lead to increased post operative complications. Non ionic water-soluble contrast should be used, as the hyperosmolar agents, if aspirated, can result in life-threatening pulmonary edema. When reflective of duodenal atresia, associations with Down syndrome and VACTERL sequence abnormalities are often seen. [5]
Certain rare anatomic anomalies, such as congenital duodenal duplication [6] and pyloric atresia [7] can cause false positives for the sign on radiographs. Congenital pyloric atresia usually causes a single bubble on radiographs without distal gas, though an intermittent double bubble sign is occasionally seen. [8] Duodenal atresia, while typically without distal gas, has been reported with an absent double bubble, though this variant is quite rare. [9] On neonatal ultrasound, a double bubble can also be caused by a choledochal cyst, omental cyst, or enteric duplication cyst.
The small intestine or small bowel is an organ in the gastrointestinal tract where most of the end absorption of nutrients and minerals from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the pancreatic duct to aid in digestion.
Caroli disease is a rare inherited disorder characterized by cystic dilatation of the bile ducts within the liver. There are two patterns of Caroli disease: focal or simple Caroli disease consists of abnormally widened bile ducts affecting an isolated portion of liver. The second form is more diffuse, and when associated with portal hypertension and congenital hepatic fibrosis, is often referred to as "Caroli syndrome". The underlying differences between the two types are not well understood. Caroli disease is also associated with liver failure and polycystic kidney disease. The disease affects about one in 1,000,000 people, with more reported cases of Caroli syndrome than of Caroli disease.
Bowel obstruction, also known as intestinal obstruction, is a mechanical or functional obstruction of the intestines which prevents the normal movement of the products of digestion. Either the small bowel or large bowel may be affected. Signs and symptoms include abdominal pain, vomiting, bloating and not passing gas. Mechanical obstruction is the cause of about 5 to 15% of cases of severe abdominal pain of sudden onset requiring admission to hospital.
An upper gastrointestinal series, also called a barium meal, is a series of radiographs used to examine the gastrointestinal tract for abnormalities. A contrast medium, usually a radiocontrast agent such as barium sulfate mixed with water, is ingested or instilled into the gastrointestinal tract, and X-rays are used to create radiographs of the regions of interest. The barium enhances the visibility of the relevant parts of the gastrointestinal tract by coating the inside wall of the tract and appearing white on the film. This in combination with other plain radiographs allows for the imaging of parts of the upper gastrointestinal tract such as the pharynx, larynx, esophagus, stomach, and small intestine such that the inside wall lining, size, shape, contour, and patency are visible to the examiner. With fluoroscopy, it is also possible to visualize the functional movement of examined organs such as swallowing, peristalsis, or sphincter closure. Depending on the organs to be examined, barium radiographs can be classified into "barium swallow", "barium meal", "barium follow-through", and "enteroclysis". To further enhance the quality of images, air or gas is sometimes introduced into the gastrointestinal tract in addition to barium, and this procedure is called double-contrast imaging. In this case the gas is referred to as the negative contrast medium. Traditionally the images produced with barium contrast are made with plain-film radiography, but computed tomography is also used in combination with barium contrast, in which case the procedure is called "CT enterography".
Abdominal pain, also known as a stomach ache, is a symptom associated with both non-serious and serious medical issues.
Pyloric stenosis is a narrowing of the opening from the stomach to the first part of the small intestine. Symptoms include projectile vomiting without the presence of bile. This most often occurs after the baby is fed. The typical age that symptoms become obvious is two to twelve weeks old.
Omphalocele or omphalocoele also called exomphalos, is a rare abdominal wall defect in which the intestines, liver and occasionally other organs remain outside of the abdomen in a sac because of failure of the intestines and other contents to return to the abdominal cavity during around the sixth week of intrauterine development. Prior to this time, the intestines protrude into the umbilical cord in utero as a normal result of rapid intestinal growth, but they recede around the ninth week of development as the body grows.
Enteric duplication cysts, sometimes simply called duplication cysts, are rare congenital malformations of the gastrointestinal tract. They most frequently occur in the small intestine, particularly the ileum, but can occur anywhere along the gastrointestinal tract. They may be cystic or tubular in conformation.
A volvulus is when a loop of intestine twists around itself and the mesentery that supports it, resulting in a bowel obstruction. Symptoms include abdominal pain, abdominal bloating, vomiting, constipation, and bloody stool. Onset of symptoms may be rapid or more gradual. The mesentery may become so tightly twisted that blood flow to part of the intestine is cut off, resulting in ischemic bowel. In this situation there may be fever or significant pain when the abdomen is touched.
Intestinal malrotation is a congenital anomaly of rotation of the midgut. It occurs during the first trimester as the fetal gut undergoes a complex series of growth and development. Malrotation can lead to a dangerous complication called volvulus.Malrotation can refer to a spectrum of abnormal intestinal positioning, often including:
Necrotizing enterocolitis (NEC) is a medical condition where a portion of the bowel dies. It typically occurs in newborns that are either premature or otherwise unwell. Symptoms may include poor feeding, bloating, decreased activity, blood in the stool, or vomiting of bile.
Annular pancreas is a rare condition in which the second part of the duodenum is surrounded by a ring of pancreatic tissue continuous with the head of the pancreas. This portion of the pancreas can constrict the duodenum and block or impair the flow of food to the rest of the intestines. It is estimated to occur in 1 out of 12,000 to 15,000 newborns. The ambiguity arises from the fact that not all cases are symptomatic.
Pneumoperitoneum is pneumatosis in the peritoneal cavity, a potential space within the abdominal cavity. The most common cause is a perforated abdominal organ, generally from a perforated peptic ulcer, although any part of the bowel may perforate from a benign ulcer, tumor or abdominal trauma. A perforated appendix seldom causes a pneumoperitoneum.
Distal intestinal obstruction syndrome (DIOS) involves obstruction of the distal part of the small intestines by thickened intestinal content and occurs in about 20% of mainly adult individuals with cystic fibrosis. DIOS was previously known as meconium ileus equivalent, a name which highlights its similarity to the intestinal obstruction seen in newborn infants with cystic fibrosis. DIOS tends to occur in older individuals with pancreatic insufficiency. Individuals with DIOS may be predisposed to bowel obstruction, though it is a separate entity than true constipation.
Intestinal atresia is any congenital malformation of the structure of the intestine that causes bowel obstruction. The malformation can be a narrowing (stenosis), absence or malrotation of a portion of the intestine. These defects can either occur in the small or large intestine.
'Hematocolpos' is a medical condition in which the vagina is pooled with menstrual blood due to multiple factors leading to the blockage of menstrual blood flow. The medical definition of Hematocolpos is 'an accumulation of blood within the vagina'. It is often caused by the combination of menstruation with an imperforate hymen. It is sometimes seen in Robinow syndrome, uterus didelphys, or other vaginal anomalies.
Duodenal atresia is the congenital absence or complete closure of a portion of the lumen of the duodenum. It causes increased levels of amniotic fluid during pregnancy (polyhydramnios) and intestinal obstruction in newborn babies. Radiography shows a distended stomach and distended duodenum, which are separated by the pyloric valve, a finding described as the double-bubble sign.
Pulmonary hypoplasia is incomplete development of the lungs, resulting in an abnormally low number or size of bronchopulmonary segments or alveoli. A congenital malformation, it most often occurs secondary to other fetal abnormalities that interfere with normal development of the lungs. Primary (idiopathic) pulmonary hypoplasia is rare and usually not associated with other maternal or fetal abnormalities.
Congenital pulmonary airway malformation (CPAM), formerly known as congenital cystic adenomatoid malformation (CCAM), is a congenital disorder of the lung similar to bronchopulmonary sequestration. In CPAM, usually an entire lobe of lung is replaced by a non-working cystic piece of abnormal lung tissue. This abnormal tissue will never function as normal lung tissue. The underlying cause for CPAM is unknown. It occurs in approximately 1 in every 30,000 pregnancies.
Neonatal bowel obstruction (NBO) or neonatal intestinal obstruction is the most common surgical emergency in the neonatal period. It may occur due to a variety of conditions and has an excellent outcome based on timely diagnosis and appropriate intervention.