Atresia
Encyclopedia
Atresia is a condition in which a body orifice
or passage in the body is abnormally closed or absent.
Examples of atresia include:
Orifice
An orifice is any opening, mouth, hole or vent, as of a pipe, plate, or a body.* Body orifice* Orifice plate* Calibrated orifice* Nozzle* Back Orifice-See also:* Choked flow* Needle valve* Venturi effect* Flow measurement...
or passage in the body is abnormally closed or absent.
Examples of atresia include:
- Imperforate anusImperforate anusAn imperforate anus or anal atresia is a birth defect in which the rectum is malformed. Its cause is unknown.-Features:There are several forms of imperforate anus:* A low lesion, in which the colon remains close to the skin...
- malformation of the opening between the rectum and anus. - MicrotiaMicrotiaMicrotia, also called microtia-anotia, is a congenital deformity where the pinna is very small and underdeveloped or absent . It can be unilateral or bilateral . It occurs in 1 out of about 8,000–10,000 births. In unilateral microtia, the right ear is most commonly affected...
- Absence of the ear canal or failure of the canal to be tubular or fully formed (can be related to MicrotiaMicrotiaMicrotia, also called microtia-anotia, is a congenital deformity where the pinna is very small and underdeveloped or absent . It can be unilateral or bilateral . It occurs in 1 out of about 8,000–10,000 births. In unilateral microtia, the right ear is most commonly affected...
- a congenital deformity of the pinna (outer ear).) - Biliary atresiaBiliary atresiaBiliary atresia, also known as "extrahepatic ductopenia" and "progressive obliterative cholangiopathy" is a congenital or acquired disease of the liver and one of the principle forms of chronic rejection of a transplanted liver allograft. As a birth defect in newborn infants, it has an occurrence...
- Condition in newborns in which the common bile duct between the liver and the small intestine is blocked or absent. - Choanal atresiaChoanal atresiaChoanal atresia is a congenital disorder where the back of the nasal passage is blocked, usually by abnormal bony or soft tissue formed during fetal development.-Presentation:It can be unilateral or bilateral....
- blockage of the back of the nasal passage, usually by abnormal bony or soft tissue. - Esophageal atresiaEsophageal atresiaEsophageal atresia is a congenital medical condition which affects the alimentary tract. It causes the esophagus to end in a blind-ended pouch rather than connecting normally to the stomach. It comprises a variety of congenital anatomic defects that are caused by an abnormal embryological...
- affects the alimentary tract causing the esophagus to end before connecting normally to the stomach. - Intestinal atresiaIntestinal atresiaIntestinal atresia is a malformation where there is a narrowing or absence of a portion of the intestine. This defect can either occur in the small or large intestine.-Types of intestinal atresia:...
- malformation of the intestine, usually resulting from a vascular accident in utero - Ovarian follicle atresiaOvarian follicle atresiaOvarian follicle atresia is the periodic process in which immature ovarian follicles degenerate and are subsequently re-absorbed during the follicular phase of the menstrual cycle. Typically around 20 follicles mature each month and only a single follicle is ovulated. The rest undergo atresia...
, atresia refers to the degeneration and subsequent resorption of one or more immature ovarian follicleOvarian follicleOvarian follicles are the basic units of female reproductive biology, each of which is composed of roughly spherical aggregations of cells found in the ovary. They contain a single oocyte . These structures are periodically initiated to grow and develop, culminating in ovulation of usually a single...
s. - Pulmonary atresiaPulmonary atresiaPulmonary atresia is a congenital malformation of the pulmonary valve in which the valve orifice fails to develop. The valve is completely closed thereby obstructing the outflow of blood from the heart to the lungs. The pulmonary valve is located on the right side of the heart between the right...
- malformation of the pulmonary valve in which the valve orifice fails to develop. - Tricuspid atresiaTricuspid atresiaTricuspid atresia is a form of congenital heart disease whereby there is a complete absence of the tricuspid valve. Therefore, there is an absence of right atrioventricular connection. This leads to a hypoplastic or absent right ventricle....
- a form of congenital heart disease whereby there is a complete absence of the tricuspid valve. Therefore, there is an absence of right atrioventricular connection. - Vaginal atresiaVaginal atresiaVaginal Atresia is a birth defect or congenital abnormality of the female genitourinary system that manifests itself in the absence of a vagina , or a deformed and nonfunctional vagina ....
- congenital occlusion of the vagina or subsequence adhesion of the walls of the vagina occluding it. - Potter sequence - congenital decreased size of the kidney leading absolute no functionality of the kidney, usually related to a single kidney.
- Aural Atresia - refers to the absence of an external ear canal, often with malformation of the external, middle, and/or inner ear. It can be a symptom of other syndromes (Hemifacial Microsomia, 18-q chromosome, and several others).