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Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

1,227 results found
Article

Thyroglossal duct cyst

Thyroglossal duct cysts (TGDC) are the most common type of congenital neck cysts and pediatric neck masses. They are typically located in the midline and are the most common midline neck mass in young patients. They can be diagnosed with multiple imaging modalities including ultrasound, CT and M...
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Thyroid transcription factor 1 deficiency

Thyroid transcription factor 1 deficiency is a situation characterized by mutations in the gene encoding thyroid transcription factor, NKX2-1. Pathology It can result in neurological, thyroid, and pulmonary dysfunction (including neonatal respiratory distress). Children can have a range of mil...
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Tibia vara

Tibia vara (also known as genu varus and bow-leggedness) is a varus deformity with outward bowing at the knee and medial angulation (inward) of the lower leg in relation to the thigh's coronal axis. The differential of bow-legging in children is long, with common causes including Blount disease...
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Tibiotalar slant

Tibiotalar slant is the superolateral inclination of the tibial plafond, and results in an ankle valgus deformity. There are a number of causes 1: trauma, i.e. distal tibial fractures osteomyelitis and/or septic arthritis juvenile idiopathic arthritis haemophilic arthropathy sickle cell dis...
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Tight filum terminale syndrome

Tight filum terminale syndrome, or tight filum syndrome, is a subtype of the tethered cord syndrome that is attributed to a thick, short, and/or otherwise inelastic filum terminale rather than other tethering agents. Terminology The term "tight filum terminale syndrome" is synonymous with "tet...
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Tit sign (pyloric stenosis)

The tit sign of pyloric stenosis is seen on barium studies as an outpouching of the lesser curve of the stomach proximal to the impression of the hypertrophied pyloric muscle. It represents the transient trap of contrast medium between a peristaltic wave and the thickened, hypertrophied pyloric...
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Toddler fracture

A toddler fracture is a minimally or undisplaced spiral fracture, usually of the tibia, typically encountered in toddlers. It is a potentially difficult diagnosis to establish on account of both the symptoms and imaging findings being subtle. Terminology The term has sometimes also been used t...
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Torsion of the appendix testis

Torsion of the appendix testis (occasionally called torsion of the hydatid of Morgagni) is the most common cause of an acute painful hemiscrotum in a child. The appendix testis is located at the upper pole of the testis (between the testis and the head of the epididymis). The normal appendix te...
Article

Torticollis

Torticollis (wryneck) is a clinical finding of head tilt with or without rotational spinal malalignment. It is not a diagnosis in itself and there are a wide range of underlying conditions. It is most common in the pediatric age group.  Pathology Torticollis can be acute (<1 week) or chronic (...
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Torus fracture

Torus fractures, also known as buckle fractures, are incomplete fractures of the shaft of a long bone that is characterized by bulging of the cortex. They result from trabecular compression due to an axial loading force along the long axis of the bone. They are usually seen in children, frequent...
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Total anomalous pulmonary venous return

Total anomalous pulmonary venous return (TAPVR) is a cyanotic congenital heart anomaly with abnormal drainage anatomy of the entire pulmonary venous system. This contrasts with partial anomalous pulmonary venous return (PAPVR) where only part of the pulmonary venous anatomy is abnormal. In TAPV...
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Total repair of tetralogy of Fallot

Total repair of tetralogy of Fallot is a corrective surgical procedure that involves closure of the ventricular septal defect (VSD) and relief of right ventricular outflow tract (RVOT) obstruction. Procedure Most patients with tetralogy of Fallot (TOF) undergo elective surgical repair between ...
Article

Townes-Brocks syndrome

Townes-Brocks syndrome (Renal-Ear-Anal-Radial (REAR) syndrome) is a rare autosomal dominant disease characterized by renal, anal, ear, and thumb abnormalities. Clinical presentation The major manifestations of this syndrome include: renal: displaced or rotated kidneys, horseshoe kidney, p...
Article

Tracheal buckling

Tracheal buckling is a normal finding in young infants when it is more flexible. There is typically deviation of the trachea anteriorly and to the right (up to 90°) and any other configuration (i.e. to the left or posteriorly) should raise the possibility of underlying pathology.  Practical poi...
Article

Tracheal stenosis

Tracheal stenosis is usually acquired following intubation or tracheostomy. It can also arise as part of the spectrum of tracheobronchial stenosis. Pathology Inflammation and pressure necrosis of the tracheal mucosa most commonly occur at either the tracheostomy stoma or at the level of the tu...
Article

Trampoline fracture

Trampoline fractures are transverse fractures of the proximal tibial metaphysis that occur in children while jumping on a trampoline (or inflatable castle). The fracture is thought to occur when a second, usually heavier individual causes the jumping surface to recoil upwards as the unsuspectin...
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Transient intussusception

Transient (non-obstructing) intussusception without a lead point is known to occur in both adults and children and occurs more frequently than was previously reported. Most commonly, transient intussusception in adults is idiopathic, incidental, and of no clinical consequence 4. Uncommonly, tra...
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Transient synovitis of the hip

Transient synovitis of the hip refers to a self-limiting acute inflammatory condition affecting the synovial lining of the hip. It is considered one of the most common causes of hip pain and limping in young children. Over 90% of hip joint effusions in children tend to be due to transient synovi...
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Transient tachypnea of the newborn

Transient tachypnea of the newborn, also known as retained fetal fluid or wet lung disease, presents in the neonate as tachypnea for the first few hours of life, lasting up to one day. The tachypnea usually resolves within 48 hours.  Epidemiology Transient tachypnea is one of the commonest cau...
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Transposition of the great arteries

Transposition of the great arteries (TGA) (also known as transposition of the great vessels (TGV)) is the most common cyanotic congenital cardiac anomaly presenting during the newborn period, with cyanosis in the first 24 hours of life. It accounts for up to 7% of all congenital cardiac anomalie...
Article

Transverse vaginal septum

Transverse vaginal (transvaginal) septum (TVS) is a type of rare congenital uterovaginal anomaly (class II under the Rock and Adam classification). Epidemiology It is rare with a frequency of 1 in 70,000 females. Clinical presentation In the case of a complete septum, patients commonly prese...
Article

Treacher Collins syndrome

Treacher Collins syndrome, also known as mandibulofacial dysostosis, is an autosomal dominant genetic abnormality and results from bilateral malformations of first and second branchial arches (see branchial apparatus). Epidemiology The incidence is estimated at approximately 1 in 50,000 live b...
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Triangular cord sign (biliary atresia)

The triangular cord sign is a triangular or tubular echogenic cord of fibrous tissue seen in the porta hepatis at ultrasonography and is relatively specific for the diagnosis of biliary atresia 1,2. This sign is useful in the evaluation of infants with cholestatic jaundice, helping in the diffe...
Article

Tricuspid atresia

Tricuspid atresia is a cyanotic congenital cardiac anomaly which is characterized by agenesis of the tricuspid valve and right ventricular inlet. There is almost always an obligatory intra-atrial connection through either an ASD or patent foramen ovale (PFO) in order for circulation to be comple...
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Trident acetabulum

Trident acetabulum is an appearance which can be seen in several skeletal dysplasias 1. It is characterized by small bony spurs at the medial and lateral acetabular margins with a more subtle central spur, resembling a trident, the three-pronged spear of classical Greece 1.  The appearance has...
Article

Trident appearance (disambiguation)

The trident appearance (or sign) can refer to a variety of entities: trident acetabulum trident hand trident sign (osmotic demyelination) trident sign (persistent trigeminal artery) History and etymology The trident is a three-pronged lance employed for spearing fish, and in Classical myth...
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Trident hand

A trident hand is a description where the hands are short with stubby fingers, with a separation between the middle and ring fingers. It may be used for the clinical appearance of the hand or the appearance on imaging, particularly reminiscent of a trident on fetal ultrasound 5. It can be seen ...
Article

Trigonocephaly

Trigonocephaly refers to the triangular appearance of the frontal skull created by premature fusion of the metopic suture (metopic craniosynostosis) 2.  Trigonocephaly accounts for around 5% of all craniosynostosis cases. Pathology The metopic suture divides the frontal bones in the midline. I...
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Trilateral retinoblastoma

Trilateral retinoblastoma refers to the combination of retinoblastoma (usually bilateral) and pineoblastoma. This relationship highlights the close relationship between these highly aggressive small round blue cell tumors. It affects only a minority of patients with retinoblastoma (1.5-5%) and ...
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Triphalangeal thumb

Triphalangeal thumb is considered a form of pre-axial polydactyly. Epidemiology Triphalangeal thumbs have an incidence of 1 in 25,000 7.  Pathology A triphalangeal thumb, as the name implies, has three phalanges instead of the usual two. There is an autosomal dominant genetic transmission 8,...
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Triplane fracture

Triplane or triplanar fractures are of the distal tibia only occurring in adolescents. As the physiological closure of the physeal plate begins medially, the lateral (open) physis is prone to this type of fracture. The name is due to the fact of the fracture expanding both in frontal and lateral...
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Triple bubble sign

The triple bubble sign is the classic radiographic appearance observed in jejunal atresia 1,2. The appearance is due to a proximal obstruction caused by the atretric jejunum. It is equivalent to the double bubble sign, but a third bubble is seen because of proximal jejunal distention.
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Triradiate cartilage

The triradiate cartilage is the Y- shaped epiphyseal plate that occurs at the junction where the ischium, ilium, and pubis meet in the skeletally immature skeleton.   The vertical component of the "Y" is the meeting of the ischium and pubic bone. The anterior arm is the junction of the ilium an...
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Trisomies

The trisomies are chromosomal anomalies which usually occur due to non-disjunction. The vast majority of affected fetuses are spontaneously aborted, often very early during gestation. Only three are compatible with extrauterine life (T13, T18, T21), and only one beyond early infancy (T21). In o...
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True hermaphroditism

True hermaphroditism is a form of disorder of gender development.  Pathology Patients with true hermaphroditism have mosaicism of 46XX and 46XY. They therefore have both ovarian and testicular tissues. Subtypes There are three forms of true hermaphroditism: unilateral true hermaphroditism ...
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Truncus arteriosus

Truncus arteriosus is a cyanotic congenital heart anomaly in which a single trunk supplies both the pulmonary and systemic circulation, instead of a separate aorta and a pulmonary trunk. It is usually classified as a conotruncal anomaly. It accounts for up to 2% of congenital cardiac anomalies ...
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Tuberous sclerosis

Tuberous sclerosis, also known as tuberous sclerosis complex or Bourneville disease, is a neurocutaneous disorder (phakomatosis) characterized by the development of multiple benign tumors of the embryonic ectoderm (e.g. skin, eyes, and nervous system). Epidemiology Tuberous sclerosis has an in...
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Tubulinopathy

Tubulinopathies refer to a wide spectrum of cortical malformations that result from defects in genes encoding the tubulin protein that regulates neuronal migration during brain development. Clinical presentation Some series report a high prevalence of seizures during infancy which may the init...
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Turtle sign (clinical)

Turtle sign may refer to the ultrasound turtle sign or a clinical sign of fetal shoulder dystocia in which the fetal head retracts 3. The head bobbing, emerging and then pulling back could be conceptualized as similar to a turtle pulling it's head into and out of it's shell. The sign does not ne...
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Type I choledochal cyst

Type I choledochal cysts appear as a fusiform or cystic dilatation of the extrahepatic biliary system (common bile duct +/- common hepatic duct). Epidemiology Although uncommon in Western countries (1:100,000 to 1:150,000), they are the most common type of biliary cyst. Their prevalence may be...
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Type II collagenopathy

Type II collagenopathies are a group of conditions collectively characterized by abnormalities in synthesis of collagen type II. This usually occurs due to a mutation in the COL2A1 gene. Entities that fall under this group include: achondrogenesis type II platyspondylic lethal skeletal dyspla...
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Typhoid fever

Typhoid fever or just typhoid is an infectious disease caused by the Salmonella enterica serovar Typhi bacterium, usually spread by the orofecal route. The condition is characterized by severe fever, acute systemic symptoms, with occasionally serious enterocolic complications. Terminology Do n...
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Tyrosinemia type 1

Tyrosinemia type 1 is an autosomal recessive disorder of metabolic origin. Progressive renal tubular defects and hepatocellular carcinoma are the primary manifestations. Epidemiology More common in Turkey, India and Europe. Clinical presentation Presentation is typically in the first few mon...
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Ulegyria

Ulegyria refers to a shrunken and flattened cortex usually due to global hypoxic ischemic injury in term infants, centering on the deepest portion of gyri, usually in the parasagittal region. It is here that perfusion is most tenuous and, therefore, most susceptible to ischemic damage. Clinical...
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Ulnar dimelia

Ulnar dimelia or mirror hand syndrome is a rare congenital anomaly of the upper limb characterized by absence of the radial ray (including thumb), duplication of the ulna and duplication of the ulnar halves of the carpals, metacarpals and phalanges 1. Pathology Embryology The embryology of mi...
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Ulnar hemimelia

Ulnar hemimelia is a rare congenital upper limb anomaly characterized by complete or partial absence of the ulna bone. Epidemiology Incidence is estimated at 1/100,000-150,000 live births, with a male to female ratio of 3:2. Associations Ulnar hemimelia may be associated with other skeletal ...
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Umbilical arterial catheters

Umbilical arterial catheters (UACs) are used in neonatal care for arterial sampling and need to be carefully assessed on all neonatal films.  Position The catheter should pass through the umbilicus, travel inferiorly through the umbilical artery, then in the anterior division of the internal i...
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Umbilical artery

The umbilical artery gives rise to both a nonfunctional remnant of the fetal circulation and an active vessel giving supply to the bladder. In the adult, the obliterated area of the vessel is identifiable as the medial umbilical ligament and the patent segment is the superior vesical artery. Su...
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Umbilical cord

The umbilical cord is a fetal organ that connects the placenta to the developing fetus and is a vital passage for nutrients, oxygen and waste products to and from the fetus. Gross anatomy The umbilical cord inserts into the center of the placental bulk and into the fetus at the umbilicus. Vari...
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Umbilical-urachal sinus

An umbilical-urachal sinus belongs to the spectrum of congenital urachal anomalies and represents a non-communicating dilatation of the urachus at the umbilical end. Clinical presentation Presentation is commoner in children and rare in adult. Radiographic features An umbilical-urachal sinus...
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Umbilical vein

The umbilical vein is the conduit for blood returning from the placenta to the fetus until it involutes soon after birth. The umbilical vein arises from multiple tributaries within the placenta and enters the umbilical cord, along with the (usually) paired umbilical arteries. Once it enters the...
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Umbilical venous catheters

Umbilical venous catheters (UVCs) are commonly used in neonates for vascular access and should be carefully assessed for position on all neonatal films.  Position An umbilical venous catheter generally passes directly superiorly and remains relatively anterior in the abdomen. It passes through...
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Umbilicus

The umbilicus is the fibrous remnant of the fetal attachment of the umbilical cord after birth. Gross anatomy All layers of the anterior abdominal wall fuse at the umbilical ring, a small round defect in the linea alba located just inferior to the midpoint between the xiphoid process of the st...
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Undifferentiated embryonal sarcoma of the liver

Undifferentiated embryonal sarcomas of the liver are rare, aggressive, and malignant liver tumors encountered in the pediatric population.  Epidemiology Approximately 90% of cases occur in patients under 15 years of age, most commonly between 6 and 10 years of age, but some cases have been rep...
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Unicameral bone cyst

Unicameral bone cysts (UBC), also known as simple bone cysts, are common benign non-neoplastic lucent bony lesions that are seen mainly in childhood and typically remain asymptomatic. They account for the S (simple bone cyst) in FEGNOMASHIC, the commonly used mnemonic for lytic bone lesions.  E...
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Unifocalisation procedure

A unifocalisation procedure is a corrective surgical technique used in patients with complete pulmonary artery atresia with major aortopulmonary collateral arteries (MAPCAs). In this technique, the collateral vessels supplying blood from the aorta directly to the lungs are brought into continuit...
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Upper limb radiography (pediatric)

Upper limb radiography involves plain film imaging of the shoulder, humerus, ulna, radius, metacarpals and carpal bones in pediatric patients. Depending on the patients' age, the difficulty of the examination will vary, often requiring a specialist trained radiographer familiar with a variety of...
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Urachal cyst

Urachal cysts are one of the manifestations of the spectrum of congenital urachal remnant abnormalities.  Epidemiology An infected urachal cyst can occur at any age. Clinical presentation Urachal cysts usually remain asymptomatic until complicated by infection or bleeding. Pathology Uracha...
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Urbach-Wiethe disease

Urbach-Wiethe disease, also known as lipoid proteinosis or hyalinosis cutis et mucosae, is a rare autosomal recessive genodermatosis that primarily affects the skin, upper respiratory tract, and central nervous system (CNS). Epidemiology Urbach-Wiethe disease is a very rare condition, with few...
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Ureteric jet

Ureteric jets (or ureteral jets) are the visualization of the normal physiological periodic efflux of urine from the distal end of each ureter into the bladder.  Pathology When the urine passing down the ureter reaches the vesicoureteric junction (VUJ), it is forced out into the bladder via a ...
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Ureterocele

Ureteroceles represent abnormal congenital dilatation of the distal-most portion of the ureter. The dilated portion of the ureter may herniate into the bladder secondary to the abnormal structure of vesicoureteric junction (VUJ). Epidemiology A ureterocele occurs in about 1 in 5000 to 1 in 120...
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Urinary bladder diverticula (causes)

There are numerous causes of urinary bladder diverticula:  Primary (congenital or idiopathic) Hutch diverticulum (in paraureteral region) Secondary bladder outlet obstruction bladder neck stenosis neurogenic bladder posterior urethral valve prostatic enlargement (hypertrophy; carcinoma) ...
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Urinary tract dilatation classification

Urinary tract dilatation (UTD) classification was a proposed unified classification of urinary tract dilatation for prenatal and postnatal care. This classification was formed with the collaborations from 8 societies (The American College of Radiology (ACR), the American Institute of Ultrasound ...
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VACTERL association

VACTERL is an acronym that describes a non-random constellation of congenital anomalies. It is not a true syndrome as such and is equivalent to the VATER anomaly. Epidemiology The estimated incidence is 1 in 10,000-40,000 births 3. Pathology The acronym VACTERL derives from: V: vertebral an...
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Vaginal stenosis

Vaginal stenosis refers to a narrowing of the vagina, it can be congenital or acquired. Clinical presentation dyspareunia painful pelvic examination Complications retrograde menstruation Pathology Causes Acquired causes include: iatrogenic scarring from prior pelvic irradiation - brach...
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Valvular heart disease

Valvular heart diseases, or cardiac valvulopathies, describe any acquired or congenital disease affecting one or more of the four cardiac valves. This is a general index article that classifies cardiac valvulopathies depending on which valve(s) is affected 1. See individual articles for in-dept...
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Van der Woude syndrome

van der Woude syndrome (VWS) is characterized by the association of congenital lower lip fistulae/pits with cleft lip and/or palate. It is one of the most common clefting syndromes in humans 1 and affected individuals have a high prevalence of hypodontia. Pathology Genetics It carries an aut...
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Van Wyk Grumbach syndrome

Von Wyk Grumbach syndrome is characterized by chronic hypothyroidism with high levels of thyroid-stimulating hormone (TSH), delayed bone age, precocious puberty but lacking pubic and axillary hair growth 1.  Epidemiology The acquired form of hypothyroidism is seen in children caused by chronic...
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Vascular rings and slings

Vascular rings and slings refer to the congenital vascular encirclement of the esophagus and/or trachea by anomalous/aberrant vessels.  Epidemiology Vascular rings are rare, occurring in <1% of patients 1. No gender or ethnic predispositions have been identified 3.  Clinical presentation Man...
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VATER

VATER (equivalent to VACTERL) is the non-random constellation of a number of congenital anomalies. V: vertebral anomalies A: anal atresia TE: tracheo-oesophageal fistulas R: radial ray hypoplasia, polydactyly and renal agenesis Epidemiology The prevalence of at least 3/5 anomalies occurs...
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Vein of Galen aneurysmal malformation

Vein of Galen aneurysmal malformations (VGAMs), probably better termed as median prosencephalic arteriovenous fistulas, are uncommon intracranial anomalies that tend to present dramatically during early childhood with features of a left-to-right shunt and high-output cardiac failure. Epidemiolo...
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Ventricular septal defect

Ventricular septal defects (VSD) represent defects in the interventricular septum that allow a hemodynamic communication between the right and left ventricles. It typically results in a left-to-right shunt. Epidemiology They represent one of the most common congenital cardiac anomalies and may...
Article

Ventriculus terminalis

The ventriculus terminalis (or persistent terminal ventricle, or terminal ventricle of Krause, or 5th ventricle) is an ependymal-lined fusiform dilatation of the terminal central canal of the spinal cord, positioned at the transition from the tip of the conus medullaris to the origin of the filu...
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Vesico-urachal diverticulum

Vesico-urachal diverticulum is one of the congenital urachal remnant abnormalities. Gross anatomy It is the proximal equivalent of a urachal umbilical sinus, representing a result of the failure of the urachus to close at the urinary bladder, forming an out-pouching of variable length from the...
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Vesicoureteric reflux

Vesicoureteric reflux (VUR) is the term for the abnormal flow of urine from the bladder into the upper urinary tract and is typically encountered in young children. For grading of vesicoureteric reflux, please refer to vesicoureteric reflux grading. Epidemiology The incidence of urinary tract...
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Vesicoureteric reflux (grading)

Vesicoureteric reflux (VUR) grading divides vesicoureteric reflux according to the height of reflux up the ureters and degree of dilatation of the ureters: grade 1: reflux limited to the ureter grade 2: reflux up to the renal pelvis grade 3: mild dilatation of ureter and pelvicalyceal system ...
Article

Vesicovaginal reflux

Vesicovaginal reflux is a well-known entity rarely encountered by radiologists. It is a behavioral disorder, a type of dysfunctional elimination syndrome commonly encountered in pre-pubertal girls. It is defined as reflux of urine into the vaginal vault either in supine or upright position durin...
Article

Vitamin A

Vitamin A are a group of fat-soluble vitamers (the retinoids) required for many physiological functions, mainly vision, reproduction and epithelial maintenance. In the retina, a specific retinoid, 11-cis-retinal, is formed by photoisomerisation within the rods and cones. Related pathology Path...
Article

Vitamin B1

Vitamin B1 (thiamine) is a water-soluble vitamin, that is part of the vitamin B complex, and is an important coenzyme for two reactions in the citric acid cycle (Kreb cycle). It therefore is vital for cellular ATP production, particularly in the central nervous system. Terminology Thiamine is ...
Article

Vitamin B6 deficiency

Vitamin B6 deficiency (also known as hypovitaminosis B6) is rare, as the B6 vitamers are present in many commonly-consumed foodstuffs. It is most commonly seen in the context of chronic ethanol excess, although many other risk factors are known. In children, deficiency may manifest as seizures. ...
Article

Vitamin C

Vitamin C (ascorbic acid) is a water soluble vitamin that is a coenzyme for the formation of the structure protein collagen, particularly creating cross-linking of collagen fibers which greatly increases its tensile strength. It also acts as an antioxidant. History and etymology Vitamin C was ...
Article

Vitamin D

Vitamin D (calciferol) is used to describe a group of five fat-soluble secosteroid vitamins required for the homeostasis of serum calcium and phosphorus. Vitamin D exists in two main forms (vitamers) in humans: ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3).  Vitamin D3 acts by re...
Article

Vitamin D deficiency (overview)

Vitamin D deficiency (also known as hypovitaminosis D) is common, and untreated, may result in serious sequelae. Traditionally its pathological manifestations have been regarded through the lens of skeletal maturity: rickets in children osteomalacia in adults However it has become increasingl...
Article

Vitamin E

Vitamin E (the tocopherols) are a group of fat-soluble vitamins that act as antioxidants. hypovitaminosis E is rarely seen outside premature infants hypervitaminosis E is extremely rare as the toxicity of vitamin E is low except in chronic (usually >1 year) high doses. The commonest sequela is...
Article

Vitamin K

Vitamin K is not a single compound but a family of fat-soluble vitamins essential for normal blood-clotting function and comprises two vitamers that are found naturally: phytomenadione (also known as phylloquinone or K1) and menaquinone (or K2). Menaquinone (K2) is synthesized by normal flora i...
Article

Voiding cystourethrography

Voiding cystourethrography (VCUG), also known as a micturating cystourethrography (MCU),  is a fluoroscopic study of the lower urinary tract in which contrast is introduced into the bladder via a catheter. The purpose of the examination is to assess the bladder, urethra, postoperative anatomy an...
Article

Waardenburg syndrome

Waardenburg syndrome is a rare congenital pigmentary disorder secondary to an abnormal distribution of neural crest-derived melanocytes during embryogenesis resulting in patchy areas of depigmentation. It is considered in the investigation of congenital sensorineural deafness. Epidemiology Est...
Article

WAGR syndrome

The WAGR syndrome or complex stands for: Wilms tumors (greatly increased risk) aniridia genitourinary anomalies intellectual retardation (disability) Pathology Genetics Occurs from a mutation related to chromosome 11p13 3 which is in close proximity to the WT1 gene.
Article

Waldenström classification of Perthes disease

The Waldenström classification of Perthes disease refers to x-ray abnormalities, and represents four temporal phases of the disease. These stages have been further subdivided in the modified Elizabethtown classification 2. stage I: early asymmetric femoral epiphyseal size (smaller on the affec...
Article

Walker-Warburg syndrome

Walker-Warburg syndrome (WWS), sometimes known as HARDE syndrome, is an extremely rare lethal form of congenital muscular dystrophy. It is primarily characterized by: fetal hydrocephalus: almost always present neuronal migrational anomalies: agyria (cobblestone lissencephaly / lissencephaly ty...
Article

Waterston shunt

A Waterston shunt is a form of palliative surgery performed in patients with tetralogy of Fallot prior to the ability to repair the defect. It consists of a shunt formed between the ascending aorta and the right pulmonary artery. This does not relieve the right ventricular outflow obstruction, ...
Article

Weaver syndrome

Weaver syndrome (WS) is a rare congenital disorder. Clinical spectrum increased birth weight: fetal macrosomia early overgrowth macrocephaly accelerated osseous maturation: increased bone age typical facial features broad forehead hypertelorism long philtrum micrognathia large ears h...
Article

Weightbearing foot series (an approach)

Reporting a weightbearing foot series can be a daunting process if you are inexperienced and often results in the films being left for somebody else to report. This article attempts to demystify the whole process by providing a structured approach to their reporting. Technique The weightbearin...

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