Glossary:
Explanation of Medical Terms

Amniotic cavity: The space within the uterus in which the fetus resides, and bound by the amniotic membrane

Aorta: the main artery in the body; it comes directly off the left ventricle of the heart, and carries oxygen-rich blood to the entire body

Bronchogenic cyst: A lesion, found in the fetus, that develops when a portion of bronchus buds off from the rest of the lung and airways. Because the lining of the airways normally secretes some fluid, a bronchogenic cyst is filled with the same type of fluid, and appears as a fluid-filled mass

Bronchopulmonary: related to the lung and airways. Bronchopulmonary sequestration: see Sequestration

Bronchus: airway; tube-like structure whose function is to allow air to travel to and from the lung

Congenital: condition that is present at or before birth. A congenital lung lesion is a lung lesion that is present in the fetus

Congenital diaphragmatic hernia (CDH): a hole in the diaphragm found in the fetus; it causes the intestines and other abdominal organs to move into the chest and compress the lungs, and often causes severe breathing problems at birth

Congenital lobar emphysema (CLE): a lung condition found in the fetus and the infant, whereby a portion of the lung is bloated and distended, because of a temporary and/or incomplete blockage of the corresponding airway. After birth, the lung tissue in that segment of the lung is distended and does not function properly

Cyst: a fluid-filled cavity

Cystic adenomatoid malformations (CCAM): a type of lung lesion that is composed of disorganized lung tissue. It can be mostly cystic (fluid-filled cavity), solid, or a combination of both

Diaphragm: the thin muscle layer that separates the chest from the abdominal cavity

"Double pigtail" catheter: a fine tube that can be left in a body cavity, such as the chest of the fetus. The pigtails refer to the curled ends of the catheter, which keep the catheter in place in that cavity

Esophagus: the food-pipe. In the embryo, the trachea (wind-pipe) and bronchi (the smaller airways) form from an outpouching of the upper portion of the esophagus

Extralobar: see Sequestration

Fetal: related to the fetus

Hybrid: that is composed of more than one type of tissue or structure. A hybrid lung lesion may be a sequestration with CCAM elements

Hydrops: heart failure in the fetus. It can manifest itself by enlargement of the heart, abnormal accumulation of fluid around the heart, around the lungs, in the abdominal cavity or under the skin

Intralobar: see Sequestration

Intubation: placement of a tube; refers specifically to the insertion of a plastic tube in someone's wind-pipe (trachea) and connecting it to a breathing machine (ventilator or respirator)

Lung abscess: a form of lung infection whereby the bacteria form a cavity surrounded by a thick wall through which blood vessels (and antibiotics) cannot penetrate. The abscess cavity is filled with pus, and treatment requires incision and drainage ("lancing")

Magnetic resonance imaging (MRI): A type of imaging test that does not use radiation, and provides very detailed images of the inside of the body. To obtain good images, the patient should lay still while the body is being scanned. Now that MRI machines take only a few seconds to do this, it is possible to obtain detailed images of the fetus

Malignant: cancerous

Minimally invasive surgery thoracoscopy or laparoscopy): a newer form of surgical access to a body cavity: instead of making a wide incision and opening the cavity (chest or abdomen), small tubes are inserted and surgical procedures are performed inside the cavity using long, fine instruments and a miniaturized camera

Pulmonary hypoplasia: impaired growth and development of the lung. It can be caused by a variety of conditions, such as prolonged compression of the fetal lung by a large lesion in the chest or abdominal organs that have migrated through a hole in the diaphragm

Sequestration: A type of lung lesion found in the fetus. A sequestration develops when a portion of lung tissue (with its accompanying bronchus) becomes separated from the tracheobronchial tree. It contains normally organized lung tissue, but cannot function properly, since it is cut off from the normal airways. If the splitting off occurs early in the embryo, it will be completely separated from the normal lung (extralobar sequestration); if the splitting off occurs later, the sequestration will be found inside the normal lung (a so-called intralobar sequestration)

Trachea: the wind-pipe; the upper portion of the airways. It divides in two branches, the left and right main stem bronchus. Each main stem bronchus is the main airway to a lung

Tracheobronchial tree: another name for the airways. The trachea divides into two main stem bronchi, which in turn divide into smaller branches, resembling an (upside-down) tree

Thoracentesis: A technique whereby fluid is aspirated from the chest cavity (or cyst in the chest cavity) through a fine needle

Thoracotomy: an "open" operation of the chest, whereby a large incision is made to open the cavity

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