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.

877 results found
Article

Sitz marker study

The Sitz marker study is an older technique to estimate colonic transit time.  Indications In constipation it can help distinguish between slow colonic transit and a defecation disorder. Procedure The patient ingests a number of radio-opaque markers (plastic rings containing radio-opaque mat...
Article

Skeletal dysplasia

Skeletal dysplasia (also known as osteochondrodysplasia) refers to any abnormality in bone formation. There is a very wide clinicopathological spectrum and any part of the skeleton can be affected. Epidemiology The overall prevalence is estimated at ~2 per 10,000 live births 3. Pathology Typ...
Article

Slipped upper femoral epiphysis

Slipped upper femoral epiphysis (SUFE), also known as a slipped capital femoral epiphysis (SCFE), is a relatively common condition affecting the physis of the proximal femur in adolescents. It is one of commonest hip abnormalities in adolescence and is bilateral in ~20% of cases. Epidemiology ...
Article

Slipped upper femoral epiphysis (summary)

This is a basic article for medical students and other non-radiologists Slipped upper femoral epiphysis (SUFE), also known as a slipped capital femoral epiphysis (SCFE),  is a relatively common condition affecting the physis of the proximal femur in adolescents. It is one of commonest hip abnor...
Article

Small bowel atresia

Small bowel atresia corresponds to malformations where there is a narrowing or absence of a portion of the small bowel, which includes: duodenal atresia jejunal atresia ileal atresia
Article

Small round blue cell tumours

A number of tumours share similar histology, composed of relatively uniform primitive small round blue cells. They also share many demographic, radiographic and clinical similarities. They include: Ewing sarcoma neuroblastoma embryonal rhabdomyosarcoma pineoblastoma Wilms tumour retinoblas...
Article

Snowman sign (total anomalous pulmonary venous return)

Snowman sign refers to the configuration of the heart and the superior mediastinal borders resembling a snowman. This is seen in total anomalous pulmonary venous return (TAPVR) type I (supracardiac type). It is an abnormality of the fetal circulation wherein the entire pulmonary venous flow is ...
Article

Solitary sclerotic bone lesion

The differential diagnosis of a solitary sclerotic bone lesion is heavily influenced by the age of the patient, and includes: sclerotic metastasis solitary either because no others are present or no others have been imaged enostosis (bone island) osteosarcoma calcifying enchondroma osteobl...
Article

Spinal dysraphism

Spinal dysraphism is a broad term given to a group of anomalies where there are malformations in the dorsum of the embryo. Neural tube defects come under this group as well.  Pathology There is often abnormal fusion of the midline embryonic neural, vertebral and mesenchymal structures.  Sub t...
Article

Spinal muscular atrophy

Spinal muscular atrophy (SMA) is a type of congenital neuromuscular disease affecting anterior horn cells of the brainstem and spinal cord. Epidemiology This disorder affects 1 in 6000-10000 infants 1. Clinical presentation The condition typically affects infants and young children, presenti...
Article

Spinal neurenteric cysts

Spinal neurenteric cysts are a rare type of foregut duplication cyst, accounting for ~1% of all spinal cord tumours. They are usually classified as spinal or intracranial and are associated with vertebral or CNS abnormalities respectively.  Pathology Neurenteric cysts result from incomplete re...
Article

Spleen size (paediatric)

The spleen size varies with a child's age. The three numbers below represent the 10th percentile, median, and 90th percentile for the long axis of the spleen (cm) 0-3 months: (3.3, 4.5, 5.8 cm) 3-6 months: (4.9, 5.3, 6.4 cm) 6-12 months: (5.2, 6.2, 6.8 cm) 1-2 years: (5.4, 6.9, 7.5 cm) 2-4...
Article

Spondylocostal dysostosis

Spondylocostal dysostosis (SCDO) is a rare condition characterised by short-trunk dwarfism secondary to developmental anomalies of the vertebrae and ribs. Previously the condition Jarcho-Levin syndrome (also known as spondylothoracic dysostosis) was grouped together with spondylocostal dysostosi...
Article

Spondyloepiphyseal dysplasia

Spondyloepiphyseal dysplasia is a type of skeletal dysplasia that mainly involves the spine and proximal epiphyseal centres.  Clinical presentation short neck short trunk with protruding abdomen  normal IQ spine atlanto-axial instability craniovertebral junction stenosis platyspondyly l...
Article

Sprengel deformity

Sprengel deformity, or congenital elevation of the scapula, is a complex deformity of the shoulder and is the most common congenital shoulder abnormality. An initial diagnosis can often be made on radiography, but CT or MRI is often necessary to evaluate the details of the abnormality. Clinical...
Article

Strawberry skull

Strawberry skull refers to the shape of the head on an antenatal ultrasound. Epidemiology Associations In general, strawberry skull is considered one of the non-specific 'soft markers' for abnormal fetal development. It is considered more closely associated with trisomy 18 (Edward syndrome). ...
Article

Stroke in children and young adults

Brain ischaemia/infarction in children and young adults can result from several causes. embolic phenomena cyanotic heart disease cardiomyopathies mitral valve prolapse Osler-Weber-Rendu syndrome arterial dissection trauma spontaneous fibromuscular dysplasia Marfan syndrome Ehlers Danl...
Article

Sturge-Weber syndrome

Sturge-Weber syndrome, or encephalotrigeminal angiomatosis, is a phakomatosis characterised by facial port wine stains and pial angiomas.  It is part of a wide spectrum of possible phenotypes included in the craniofacial arteriovenous metameric syndrome (CAMS). Epidemiology Sturge-Weber syndr...
Article

Subacute sclerosing panencephalitis

Subacute sclerosing panencephalitis (SSPE), also known as Dawson disease, is a rare chronic, progressive and fatal encephalitis that affects primarily children and young adults, caused by a persistent infection of immune resistant measles virus. Epidemiology  1 in 100,000 people infected with ...
Article

Subcortical leukomalacia

Subcortical leukomalacia corresponds to a continuous disease spectrum of periventricular leukomalacia (PVL) as the vascular border zones shift towards the periphery as the brain further matures. For this reason white matter lesions move from the periventricular to the subcortical zone. Please r...
Article

Subgaleal haematoma

Subgaleal haematoma describes scalp bleeding in the potential space between the periosteum and the galea aponeurosis. It most commonly occurs after vacuum-assisted delivery, but may also be seen following head trauma. In patients with intracranial haemorrhage or skull fractures, the incidence o...
Article

SUFE grading

Grading of SUFE (slipped upper femoral epiphysis) can be made on both AP and true lateral projections.  On a AP radiograph a line along the superior margin of the femoral neck (line of Klein) should intersect the lateral corner of the epiphysis. As the epiphysis slips, the metaphysis can be di...
Article

Supracondylar humeral fracture

Supracondylar humeral fractures, often simply referred to as supracondylar fractures, are a classic paediatric injury which require vigilance as imaging findings can be subtle. Epidemiology Simple supracondylar fractures are typically seen in younger children, and are uncommon in adults; 90% a...
Article

Syndactyly

Syndactyly refers to a congenital fusion of two or more digits. It may be confined to soft tissue (soft tissue syndactyly / simple syndactyly) or may involve bone (bony syndactyly / complex syndactyly). Epidemiology The overall estimated incidence is at ~1 per 2500 to 5000 live births 6,8. The...
Article

Syphilis

Syphilis is the result of infection with the gram negative spirochete Treponema pallidum, subspecies pallidum. It results in a heterogeneous spectrum of disease with many systems that can potentially be involved, which are discussed separately.  Epidemiology Despite the discovery of penicillin...
Article

Takeuchi procedure

The Takeuchi procedure refers to a direct anastomosis of the anomalous left coronary artery from the pulmonary artery directly to the aorta was described in the 1970s and currently remains the procedure of choice. An intrapulmonary aortocoronary tunnel or baffle was performed by Takeuchi prior ...
Article

Tamm-Horsfall proteins

Tamm-Horsfall proteins may be a cause of echogenic renal pyramids in a neonate. Tamm-Horsfall proteins excreted by the renal tubular epithelium. They are most often encountered on neonatal renal ultrasound, where the concentrated proteins in the renal pyramids may mimic nonobstructing renal sto...
Article

Target sign (intussusception)

The target sign of intestinal intussusception, also known as the doughnut sign or bull's eye sign. The appearance is generated by concentric alternating echogenic and hypoechogenic bands. The echogenic bands are formed by mucosa and muscularis whereas the submucosa is responsible fo the hypoec...
Article

Target sign (pyloric stenosis)

The target sign of pyloric stenosis is a sign seen due to hypertrophied hypoechoic muscle surrounding echogenic mucosa, seen in pyloric stenosis. This is likened to that of a target. See also antral nipple sign cervix sign of pyloric stenosis shoulder sign of pyloric stenosis
Article

Taussig-Bing anomaly

Taussig-Bing anomaly is a rare congenital heart malformation and is one of the variants of double outlet right ventricle. It consists of transposition of the aorta to the right ventricle and malposition of the pulmonary artery with subpulmonary ventricular septal defect. History and etymology ...
Article

Tc-99m pertechnetate

Tc-99m pertechnetate is one of the technetium radiopharmaceuticals used in imaging of thyroid, colon, bladder and stomach. Characteristics photon energy: 140 keV physical half-life biological half-life: 6 hours normal distribution: stomach, thyroid, salivary glands, (testicles) excretion: ...
Article

Technetium agents

Technetium agents based on the technetium-99m (Tc-99m) radioisotope are frequently used agents in medical imaging. The radioactive technetium radiotracer can be chelated to a number of different compounds to create specific radiopharmaceuticals and optimise the functional imaging of various stru...
Article

Tectal beaking (midbrain)

Tectal beaking refers to the fusion of the midbrain colliculi into a single beak pointing posteriorly and invaginating into the cerebellum. It is seen with a Chiari type II malformation. Terminology The term bird beak sign is used in a number of other contexts: see bird beak sign (disambiguati...
Article

Tectal glioma

Tectal gliomas fall under the grouping of childhood brainstem gliomas and unlike the other tumours in that group they are typically low grade astrocytomas with good prognosis.  Epidemiology Tectal plate gliomas are encountered in children and adolescents 4. A male predilection has sometimes be...
Article

Telephone receiver deformity

A telephone receiver deformity is a characteristic bowing of the shaft of the long bones, usually the humeri or femora, seen in thanatophoric dysplasia.
Article

Tension gastrothorax

Tension gastrothorax describes a rare life-threatening condition caused by mediastinal shift due to a distended stomach herniating into the thorax through a diaphragmatic defect.  Clinical presentation Presentation is generally with acute and severe respiratory failure, with clinical features ...
Article

Terminal myelocystocele

Terminal myelocystoceles are an uncommon form of spinal dysraphism representing marked dilatation of the central canal of the spinal cord, herniating posteriorly through a dorsal spinal defect. The result is a skin-covered mass in the lower lumbar region, consisting of an ependyma-lined sac.  E...
Article

Terminal zones of myelination

The terminal zones of myelination are located at the posterior aspect of the lateral ventricles (the peritrigonal regions) and are the only part of the cerebral white matter that may exhibit high T2 signal in a normal brain at 2 years of age, when myelination of cerebral white matter normally be...
Article

Testicular descent

Testicular descent occurs after the fourth month of fetal life. The testes are derived from the gonadal ridge medial to the mesonephric ridge of the intermediate cell mass. An elongated diverticulum of the peritoneal cavity, the processus vaginalis precedes the testis through the inguinal canal ...
Article

Tethered cord

Tethered spinal cord syndrome, also known as an occult spinal dysraphism sequence, is a neurological disorder caused by tissue attachments that limit the movement of the spinal cord within the spinal column. Clinical presentation The condition is closely linked to spina bifida, and as such pre...
Article

Tetralogy of Fallot

Tetralogy of Fallot (TOF) is the second most common cyanotic congenital heart condition and has been classically characterised by the combination of ventricular septal defect (VSD), right ventricular outflow tract obstruction (RVOTO), overriding aorta, and a late right ventricular hypertrophy. ...
Article

Thalassaemia

Thalassaemia is an autosomal recessive haemoglobinopathy that originated in the Mediterranean region. The genetic defect causes a reduction in the rate of globin chain synthesis which causes the formation of abnormal haemoglobin molecules. The resultant microcytic anaemia is the characteristic p...
Article

Thalidomide embryopathy

Thalidomide embryopathy refers to a syndrome resulting from in utero exposure to thalidomide, and is characterized by multiple fetal anomalies. Fetal exposure to thalidomide occurred primarily from 1957 to 1961, when it was used as a treatment for nausea in pregnant women.  Epidemiology  Expos...
Article

Thanatophoric dysplasia

Thanatophoric dysplasia (TD) is a lethal skeletal dysplasia. It is the most common lethal skeletal dysplasia followed by osteogenesis imperfecta type II.  Epidemiology The estimated incidence is around 1:25,000-50,000 3. Pathology Genetics It results from a mutation coding for the fibroblas...
Article

Thoracopagus conjoined twins

Thoracopagus conjoined twins are, as the name suggests, conjoined twins united at their thorax. Fusion is typically face-to-face, at the upper thorax to the umbilicus with a common sternum, diaphragm, and upper abdominal wall. Very often a common pericardial sac is present as well as a degree o...
Article

Thrombocytopenia with absent radius syndrome

Thrombocytopenia with absent radius (TAR) syndrome is primarily characterised by the following two features: fetal thrombocytopenia absent fetal radii (bilaterally) with the presence of both thumbs Epidemiology The condition is extremely rare with an estimated incidence of 0.4 per 100,000 bi...
Article

Thumb sign (epiglottitis)

The thumb sign in epiglottitis is a manifestation of an oedematous and enlarged epiglottis which is seen on lateral soft-tissue radiograph of the neck, and it suggests a diagnosis of acute infectious epiglottitis. This is the radiographic corollary of the omega sign 1-3. See also Thumb sign is...
Article

Thurstan Holland fragment

The Thurstan Holland fragment also known as the Thurstan Holland sign is an eponymous radiological sign depicting a triangular portion of the metaphysis remaining with the epiphysis in a physeal fracture. This fragment is one of the tell-tale signs of a type 2 Salter-Harris fracture 1. History ...
Article

Thymic hyperplasia

Thymic hyperplasia is a disorder whereby there is hyperplasia of the thymus gland.  Pathology Thymus hyperplasia can be subdivided into two forms:  true thymic hyperplasia lymphoid hyperplasia Both true thymic hyperplasia and lymphoid hyperplasia manifest as diffuse symmetric enlargement of...
Article

Thymic notch sign

The thymic notch sign represents the normal thymus in a newborn on a frontal chest radiograph. Interruption of the cardiac silhouette forms a notch, which may be seen on either side, but more frequently is seen on the left side. 
Article

Thymic sail sign

The thymic sail sign represents a triangular-shaped inferior margin of the normal thymus seen on a neonatal frontal chest radiograph. It is more commonly seen on the right side, but can also be bilateral. It is seen in 3-15% of all cases. This sign should not be confused with the spinnaker sail ...
Article

Thyroglossal duct cyst

Thyroglossal duct cysts (TGDC) are the most common congenital neck cyst. 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 MRI. Epidemiology Thyroglossal d...
Article

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...
Article

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...
Article

Tight filum terminale syndrome

Tight filum terminale syndrome is caused by incomplete involution of the distal spinal cord during embryogenesis. This leads to development of an abnormally thickened filum terminale, which may be associated with lipomas or cysts within the filum. Tight filum terminale syndrome is always associ...
Article

Toddler fracture

Toddler fractures are minimally or undisplaced spiral fractures usually of the tibia, typically encountered in (you guessed it) 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 a...
Article

Torsion of the appendix testis

Torsion of the appendix testis 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 testis is 1 to 4 mm in length, and it is oval or pedunculat...
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 paediatric age group.  Pathology Torticollis can be acute (<1 week) or chronic ...
Article

Torus fracture

Torus fractures, also known as buckle fractures, are incomplete fractures of the shaft of a long bone that is characterised by bulging of the cortex. They result from trabecular compression from an axial loading force along the long axis of the bone. They are usually seen in children, frequently...
Article

Total anomalous pulmonary venous return

Total anomalous pulmonary venous return (TAPVR) is a cyanotic congenital heart anomaly with an 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 T...
Article

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 characterised 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. Inflammation and pressure necrosis of the tracheal mucosa most commonly occur at either the tracheostomy stoma or at the level of the tube balloon. Acute post-intubation stenosis results from mucosal oedema or granulatio...
Article

Tracheobronchial papillomatosis

Tracheobronchial papillomatosis refers to the occurrence of multiple squamous cell papillomas involving trachea and bronchi. It is an unusual manifestation of recurrent respiratory papillomatosis (RRP), itself a rare condition where HPV-associated papilloma form along the aerodigestive tract 8. ...
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...
Article

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. Transient intussusception of the small bowel has been reported in adults with coeliac disease and Crohn disease but is most fre...
Article

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...
Article

Transient tachypnoea of the newborn

Transient tachypnoea of the newborn (TTN), also known as retained fetal fluid or wet lung disease, presents in the neonate as tachypnoea for the first few hours of life, lasting up to one day. The tachypnoea usually resolves by within 48 hours.  Epidemiology TTN is one of the commonest causes ...
Article

Transposition of the great arteries

Transposition of the great arteries (TGA) is the most common cyanotic congenital cardiac anomaly with cyanosis in the first 24 hours of life. It accounts for up to 7% of all congenital cardiac anomalies 1  and can be assessed with echocardiography, gated cardiac CT, or cardiac MRI. Epidemiology...
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

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 characterised 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...
Article

Trident acetabulum

Trident acetabulum is an appearance which can be seen in several skeletal dysplasias 1. It is characterised 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 trident is most ...
Article

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.  The appearance mimics a trident, the three-pronged spear of classical Greece. The trident is most commonly associated with the sea god Poseidon in Greek mytholo...
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...
Article

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 tumours. It affects only a minority of patients with retinoblastoma (1.5-5%) and...
Article

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....
Article

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...
Article

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.
Article

Trisomies

Trisomies are chromosomal anomalies which usually occur due to non-disjunction. The vast majority of affected fetuses being spontaneously aborted, often very early during gestation. Only three are compatible with extra-uterine life (T13, T18, T21), and only one beyond early infancy (T21). In or...
Article

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 ...
Article

Tuberous sclerosis

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

Type II collagenopathy

Type II collagenopathies are a group of conditions collectively characterised 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...
Article

Ulegyria

Ulegyria refers to a shrunken and flattened cortex usually due to global hypoxic ischaemic 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 ischaemic damage. Clinic...
Article

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...
Article

Umbilical arterial catheters

Umbilical arterial catheters are used in neonatal care 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 iliac artery, into the common ...
Article

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...
Article

Umbilical venous catheters

Umbilical venous catheters are commonly used in the neonatal period 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 thr...
Article

Undifferentiated embryonal sarcoma of the liver

Undifferentiated embryonal sarcomas of the liver are rare, aggressive, and malignant liver tumours encountered in the paediatric 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 r...
Article

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...
Article

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...
Article

Urachal cyst

Urachal cysts are one of the manifestations of the spectrum of congenital urachal remnant abnormalities.  Clinical presentation Urachal cysts usually remain asymptomatic until complicated by infection or bleeding. Epidemiology Infected urachal cyst can occur at any age. Pathology Urachal c...

Updating… Please wait.
Loadinganimation

Alert accept

Error Unable to process the form. Check for errors and try again.

Alert accept Thank you for updating your details.