Fecal incontinence (FI), also known as anal incontinence, or in some forms encopresis, is a lack of control over defecation, leading to involuntary loss of bowel contents—including flatus (gas), liquid stool elements and mucus, or solid feces. FI is a sign or a symptom, not a diagnosis. Incontinence can result from different causes and might occur with either constipation or diarrhea. Continence is maintained by several interrelated factors, including the anal sampling mechanism, and usually there is more than one deficiency of these mechanisms for incontinence to develop. The most common causes are thought to be immediate or delayed damage from childbirth, complications from prior anorectal surgery, altered bowel habits, and receptive anal sex. An estimated 2.2% of community dwelling adults are affected.
Anotia describes a rare congenital deformity that involves the complete absence of the pinna, the outer projected portion of the ear, and narrowing or absence of the ear canal. This contrasts with microtia, in which a small part of the pinna is present. Anotia and microtia may occur unilaterally or bilaterally. This deformity results in conductive hearing loss, deafness.
In the anatomy of the brain of vertebrates, the forebrain or prosencephalon is the rostral (forward-most) portion of the brain. The forebrain (prosencephalon), the midbrain (mesencephalon), and hindbrain (rhombencephalon) are the three primary brain vesicles during the early development of the nervous system. The forebrain controls body temperature, reproductive functions, eating, sleeping, and the display of emotions.
The diencephalon is a division of the forebrain, and is situated between the telencephalon and the midbrain. It consists of structures that are on either side of the third ventricle, including the thalamus, the hypothalamus, the epithalamus and the subthalamus.
Embryonic development also embryogenesis is the process by which the embryo forms and develops. In mammals, the term refers chiefly to early stages of prenatal development, whereas the terms fetus and fetal development describe later stages.
The male reproductive system consists of a number of sex organs that play a role in the process of human reproduction. These organs are located on the outside of the body and within the pelvis.
The anal canal is the terminal part of the large intestine. It is situated between the rectum and anus, below the level of the pelvic diaphragm. In humans it is approximately 2.5 to 4 cm (0.98-1.58 in) long. It lies in the anal triangle of perineum in between the right and left ischioanal fossa.
An imperforate anus or anorectal malformations (ARMs) are birth defects in which the rectum is malformed. ARMs are a spectrum of different congenital anomalies in males and females which vary from fairly minor lesions to complex anomalies. The cause of ARMs is unknown; the genetic basis of these anomalies is very complex because of their anatomical variability. In 8% of patients, genetic factors are clearly associated with ARMs. Anorectal malformation in Currarino syndrome represents the only association for which the gene HLXB9 has been identified.
The cloacal membrane is the membrane that covers the embryonic cloaca during the development of the urinary and reproductive organs.
The vaginal process is an embryonic developmental outpouching of the parietal peritoneum. It is present from around the 12th week of gestation, and commences as a peritoneal outpouching.
The pectinate line is a line which divides the upper two thirds and lower third of the anal canal. Developmentally, this line represents the hindgut-proctodeum junction.
Anorectal abscess is an abscess adjacent to the anus. It arises from an infection at one of the anal sinuses which leads to inflammation and abscess formation. Most cases of perianal abscesses are sporadic, though there are certain situations which elevate the risk for developing the disease, such as diabetes mellitus, Crohn's disease, chronic corticosteroid treatment and others. Ischiorectal, inter- and intrasphincteric abscesses have been described.
Defecography is a type of medical radiological imaging in which the mechanics of a patient's defecation are visualized in real time using a fluoroscope. The anatomy and function of the anorectum and pelvic floor can be dynamically studied at various stages during defecation.
Rectal pain is the symptom of pain in the area of the rectum. A number of different causes (68) have been documented.
Anorectal varices are the dilation of collateral submucosal vessels due to backflow in the veins of the rectum. Typically this occurs due to portal hypertension which shunts venous blood from the portal system through the portosystemic anastomosis present at this site into the systemic venous system. This can also occur in the esophagus, causing esophageal varices, and at the level of the umbilicus, causing caput medusae. Between 44% and 78% of patients with portal hypertension get anorectal varices.
Anismus is the failure of the normal relaxation of pelvic floor muscles during attempted defecation. It can occur in both children and adults, and in both men and women. It can be caused by physical defects or it can occur for other reasons or unknown reasons. Anismus that has a behavioral cause could be viewed as having similarities with parcopresis, or psychogenic fecal retention.
Endoanal ultrasound is a type of medical investigation which images the structures of the anal canal.
A keyhole defect may refer to a groove in the anal canal wall, which can occur after posterior midline fissurectomy or fistulotomy, or with lateral internal anal sphincter defects. The keyhole defect is associated with minor degrees of fecal incontinence, allowing seepage of liquid stool or mucus.
Heart development refers to the prenatal development of the human heart. This begins with the formation of two endocardial tubes which merge to form the tubular heart, also called the primitive heart tube, that loops and septates into the four chambers and paired arterial trunks that form the adult heart. The heart is the first functional organ in vertebrate embryos, and in the human, beats spontaneously by week 4 of development.
A rectovestibular fistula, also referred to simply as a vestibular fistula, is an anorectal congenital disorder where an abnormal connection (fistula) exists between the rectum and the vulval vestibule of the female genitalia.
