Radiopaedia’s Black Friday Course Sale ends Today!  SHOP NOW

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.

1,293 results found
Article

Sphenoidal fontanelles

The sphenoidal or anterolateral fontanelles are paired bilateral soft membranous gaps (fontanelles) at the junction of the coronal, sphenofrontal, sphenoparietal, sphenosquamosal, and squamosal sutures. Each sphenoidal fontanelle persists until approximately six months after birth, after which i...
Article

Sphenoid wing dysplasia

Sphenoid wing dysplasia is a characteristic but not pathognomonic feature of neurofibromatosis type 1 (NF1), it can also occur in isolated cases. Epidemiology Sphenoid wing dysplasia is seen in 5-10% of cases of NF1 and is one of the diagnostic criteria of NF1 5,6. Pathology Its exact etiolo...
Article

Spinal dysraphism

Spinal dysraphisms refer to a broad group of malformations affecting the spine and/or surrounding structures in the dorsum of the embryo. They are a form of neural tube defect. Pathology The neural tube is formed by the lengthwise closure of the neural plate, in the dorsum of the embryo. The ...
Article

Spinal muscular atrophy

Spinal muscular atrophy 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 Spinal muscular atrophy typically affects infants and young children, pres...
Article

Spinal neurenteric cyst

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

Spleen size (pediatric)

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 characterized 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 form of skeletal dysplasia mainly involving the spine and proximal epiphyses.  Clinical presentation short neck short trunk with protruding abdomen  normal IQ spine atlanto-axial instability craniovertebral junction stenosis platyspondyly scoliosis exa...
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 radiographs, but CT or MRI is often necessary to evaluate the details of the abnormality. Epidemio...
Article

Srb anomaly

The Srb anomaly describes an anatomic variant of the ribs, in which there is partial to complete bony ankylosis of the first and second ribs.
Article

Storage disorders

Storage disorders comprise a bewildering collection of inherited metabolic conditions which share the accumulation of a metabolite within various cells in the body due to dysfunction of specific enzymes or transport proteins. Accumulation of metabolites eventually results in cellular and/or orga...
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

Stroke in children and young adults can result from several causes, which are distinct from the most common causes in adults. Pathology Etiology Arterial ischemic stroke arteriopathies focal cerebral arteriopathy of childhood CNS vasculitis (e.g. large vessel childhood primary angiitis of ...
Article

Sturge-Weber syndrome

Sturge-Weber syndrome, or encephalotrigeminal angiomatosis, is a phakomatosis characterized 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

Subependymal hamartoma

Subependymal hamartomas are seen in patients with tuberous sclerosis. They are located along the ventricles and are mostly asymptomatic. As with other hamartomas, they grow at the same rate as the surrounding tissues. On imaging, they appear as small intraventricular masses, smaller than 1 cm, ...
Article

Subgaleal hematoma

Subgaleal hematoma describes scalp bleeding in the potential space between the periosteum and the galea aponeurosis. It is a rare but possibly lethal emergency. Epidemiology Moderate to severe presentations occur in 1.5 of 10,000 live births. It most commonly occurs after vacuum-assisted and f...
Article

Subpial hemorrhage

Subpial hemorrhage is a rare form of extra-axial intracranial hemorrhage defined as hemorrhage between the cortical surface and the pia mater. It is an entity that is generally difficult to distinguish from subarachnoid hemorrhage. Epidemiology Subpial hemorrhage has been typically described i...
Article

Sunset eye sign

The sunset eye sign (also known as the setting sun phenomenon) is a clinical phenomenon encountered in infants and young children with raised intracranial pressure (seen in up to 40% of children with obstructive hydrocephalus and 13% of children with shunt dysfunction 1).  It consists of an up-...
Article

Supracondylar humeral fracture

Supracondylar humeral fractures, often simply referred to as supracondylar fractures, are a classic pediatric injury which requires 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

Supratentorial ependymoma ZFTA fusion-positive

Supratentorial ependymoma ZFTA fusion-positive (previously known as RELA fusion-positive or c11orf95 fusion-positive) is a molecular variant of ependymoma, only recognized in the 2016 update to the WHO classification of CNS tumors. They are the most common type of supratentorial ependymoma in c...
Article

Surgically-created cardiac shunts (mnemonic)

A mnemonic for surgically-created cardiac shunts for congenital heart disease is: Great Flow Really Would Be Perfect​ The mnemonic is ordered by the position of the shunt antegrade to normal blood flow through the heart, proceeding from the systemic venous system into the right heart, and then...
Article

Suspected physical abuse

Suspected physical abuse (SPA), also known as non-accidental injury (NAI) or inflicted injury, in infants and young children represents both ethical and legal challenges to treating physicians. Radiologists may be the first clinical staff to suspect non-accidental injuries when confronted with ...
Article

Syndactyly

Syndactyly (plural: syndactylies) 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 2,500 to 5,000...
Article

Synovial hemangioma

Synovial hemangiomas are rare benign vascular malformations that occur in relation to the joint. It is sometimes considered a subtype of soft tissue hemangiomas. Epidemiology The lesions typically present in children and young adults. Occasionally patients can have recurrent haemarthroses 8. ...
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

Tadpole sign

The tadpole sign, also known as the lollipop sign, refers to a characteristic morphology of post-traumatic bridging vein thrombosis with a rounded "head" and a tapering "tail". The finding demonstrates a high specificity for abusive head trauma, a sub-type of non-accidental injury, and should wa...
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, also known as uromodulin, may be a cause of echogenic renal pyramids in a neonate. Tamm-Horsfall proteins are physiologically excreted by the renal tubular epithelium. They are most often encountered on neonatal renal ultrasound, where the concentrated proteins in the re...
Article

Tanner-Whitehouse method

The Tanner-Whitehouse (TW) method is a way of assessing the bone age of children. There are several variations of this method, but all use a DP radiograph of the left hand and wrist to assess the relative maturity of the bones of the patient. The TW2 (Tanner-Whitehouse 2) methods 1: RUS (radiu...
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 hypoechoic bands. The echogenic bands are formed by mucosa and muscularis whereas the submucosa is responsible fo the hypoechoi...
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 a target. See also antral nipple sign (pyloric stenosis) cervix sign (pyloric stenosis) shoulder sign (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 DMSA

Tc-99m DMSA (2,3 dimercaptosuccinic acid) is a technetium radiopharmaceutical used in renal imaging to evaluate renal structure and morphology, particularly in pediatric imaging for detection of scarring and pyelonephritis. DMSA is an ideal agent for assessment of the renal cortex as it binds to...
Article

Tc-99m pertechnetate

Tc-99m pertechnetate (Na+ 99mTc O4-) is one of the technetium radiopharmaceuticals used in imaging of thyroid, colon, bladder and stomach. Technetium (99mTc) has eight oxidation states 6, from -1 to +7; specifically, the oxidation state of technetium in the pertechnetate anion (99mTcO4-) is +7....
Article

Technetium-99m agents

Technetium agents based on the technetium-99m (Tc-99m) radioisotope are frequently used agents in medical imaging. A radiopharmaceutical labeled with Tc-99m constitutes a co-ordination complex in which ligands bond to a central atom of Tc-99m by co-ordinate covalent bonds 4 . The radioactive te...
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 tumors 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 bee...
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

Telltale triangle sign

The telltale triangle sign, also known as the triangle sign or telltale triangle, is a radiographic sign seen on plain abdominal radiographs in a supine, cross table lateral or decubitus view that signifies presence of pneumoperitoneum, of any cause 1,2. It describes the appearance of a radiolu...
Article

Temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most common type of partial epilepsy, with often characteristic imaging and clinical findings. It is divided into two broad groups: medial epilepsy most common involves the mesial temporal lobe structures most frequently due to mesial temporal sclerosis l...
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

Tethered cord syndrome

Tethered cord syndrome is a neurological disorder caused by tissue attachments that limit the movement of the spinal cord within the spinal canal. Clinical presentation Tethered cord syndrome is a clinical diagnosis based on neurologic deterioration involving the lower spinal cord 7. Patients ...
Article

Tetralogy of Fallot

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart condition with many cases presenting after the newborn period. It has been classically characterized by the combination of ventricular septal defect (VSD), right ventricular outflow tract obstruction (RVOTO), overriding aorta...
Article

Thalassemia

Thalassemia is an autosomal recessive hemoglobinopathy 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 hemoglobin molecules. The resultant microcytic anemia is the characteristic prese...
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 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 fibroblast gro...
Article

Thiemann disease

Thiemann disease (also called familial osteoarthropathy of the fingers or osteonecrosis of the base of phalanx) is a non-inflammatory disorder of unknown etiology and refers to osteonecrosis of the epiphyses of the phalanges which leads to deformity of the fingers. Epidemiology Thiemann diseas...
Article

Thoracopagus conjoined twins

Thoracopagus conjoined twins are, as the name suggests, conjoined twins united at their thorax. Thoracopagus and thoraco-omphalopagus form the most common forms of conjoined twins 3. Fusion is typically face-to-face, at the upper thorax to the umbilicus with a common sternum, diaphragm, and upp...
Article

Thrombocytopenia with absent radius syndrome

Thrombocytopenia with absent radius (TAR) syndrome is primarily characterized 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 series (pediatric)

The thumb series for pediatrics often consist of a posteroanterior and lateral view only in order to minimize radiation dose to the patient. Depending on the department and clinical indication, an additional oblique view may also be done. Indications trauma with suspected fracture suspected d...
Article

Thumb sign (epiglottitis)

The thumb sign in epiglottitis is a manifestation of an edematous 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 (or 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 indicates that a type 2 Salter-Harris fracture has occurred 1. History and etymology It...
Article

Thymic hyperplasia

Thymic hyperplasia is a disorder whereby there is hyperplasia of the thymus. Pathology Thymic hyperplasia can be subdivided into two forms:  true thymic hyperplasia lymphoid thymic 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.   See also thymic sail sign thymic wave sign  
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

Thymic wave sign

Thymic wave sign refers to the indentation of the normal thymus in young children by the ribs, resulting in a wavy border on chest radiograph.  There are at least 3 described signs relating to a normal thymus in infants; thymic sail sign, thymic notch sign and thymic wave sign. Being able to id...
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...
Article

Thyroid nodules in pediatric patients

Thyroid nodules in pediatric patients are much less common than in adults but raise greater concern due to higher rates of malignancy.  Epidemiology Thyroid nodules are much less common in children, with an estimated prevalence of around 1-2% 4, compared with adults but have higher rates of ma...
Article

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...
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, 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...
Article

Tillaux fracture

Tillaux fractures are Salter-Harris III fractures through the anterolateral aspect of the distal tibial epiphysis, with variable amounts of displacement. Epidemiology It occurs in older children and adolescents when the medial aspect of the distal tibial growth plate has started to fuse. Path...
Article

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...
Article

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...
Article

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, also known as wry neck, 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 wee...
Article

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...
Article

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...
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 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 the trachea 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.  Prac...
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...
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. Most commonly, transient intussusception in adults is idiopathic, incidental, and of no clinical consequence 4. Uncommonly, tra...
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 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...
Article

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...
Article

Triangular cord sign (biliary atresia)

The triangular cord sign is a triangular or tubular echogenic cord of fibrous tissue, representing the ductal remnant of the extrahepatic bile duct, 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 eval...
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...
Article

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...
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. 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...
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 tumors. 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.  Associations There is a long list of associations 1-6:  Aase syndrome anatomic variant: isolated anomaly Diamond-Blackfan syndrome DOOR syndrome Duan...
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...

Updating… Please wait.

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

 Thank you for updating your details.