The weightbearing lateral foot radiograph is important in the assessment of foot alignment and the diagnosis of abnormalities that cause malalignment and foot pain. Nonweightbearing views (e.g. oblique foot radiograph) are inadequate for the assessment of alignment because the bones of the feet ...
The foramen ovale (or ovalis) is the opening in the interatrial septum in the fetal heart that allows blood to bypass the right ventricle and non-ventilated lungs, shunted from the right atrium to the left atrium. Specifically it represents the opening between the upper and lower portions of the...
The fossa ovale (or ovalis) is the small oval depression in the interatrial septum at the site of the closed foramen ovale, which closes once fetal circulation ceases in the first few minutes of postnatal life. It represents the overlapping primary and secondary septa of the interatrial septum. ...
The fountain sign is sonographic sign described in acute idiopathic scrotal edema (AISE).
It refers to the appearance of the pattern of vascularity seen during transverse colour Doppler sonography of the scrotum with both testes together1. In these transverse views in patients with AISE, marked...
A fourth ventriculocoele is large posterior fossa cyst which remodels, thins and eventually erodes through the occipital bone to form an occipital encephalocoele.
It may be classified as part of the Dandy-Walker continuum, but this is controversial.
Fraser syndrome is an extremely rare congenital syndromic anomaly.
The estimated incidence is at around 0.04:10,000 live-born infants and 1:10,000 stillbirths.
The syndromic spectrum can comprises of:
syndactyly: often cutaneous
Frontal bossing is a calvarial radiographic feature where the front of the skull appears protruding anteriorly. It is best appreciated on a sagittal or lateral image.
This feature can be seen in many conditions (in alphabetical order):
Frontonasal dysplasia, also known as median cleft face syndrome, is a rare disorder characterised by midline defects involving the face, head, and central nervous system.
Frontonasal dysplasia is considered to be a very rare condition, with approximately 100 cases having been repo...
The Frykman classification of distal radial fractures is based on the AP appearance and encompasses the eponymous entities of Colles fracture, Smith fracture, Barton fracture, chauffeur fracture. It assesses the pattern of fractures, involvement of the radioulnar joint and presence of a distal u...
Fukuyama congenital muscular dystrophy (FCMD) is a form of congenital muscular dystrophy.
FCMD is almost exclusively found in Japan where it has an incidence of 2-4 per 100,000 infants and is the second most common muscular dystrophy after Duchenne muscular dystrophy 1,2. However,...
Gage sign is a V-shaped lucent defect at the lateral portion of the epiphysis and/or adjacent metaphysis. It is pathognomonic for Legg-Calve-Perthes disease.
It may occur early in the disease and is one of the five indicators of a worse prognosis, which are:
calcification lateral t...
Galeazzi fracture-dislocations consist of fracture of the distal part of the radius with dislocation of distal radioulnar joint and an intact ulna. A Galeazzi-equivalent fracture is a distal radial fracture with a distal ulnar physeal fracture 2.
Galeazzi fractures are primarily e...
Gallbladder ghost triad is a term used on ultrasound studies when there is a combination of three gallbladder features on biliary atresia:
atretic gallbladder, length less than 19 mm
irregular or lobular contour
lack of smooth/complete echogenic mucosal lining with an indistinct wall
Ganglioneuromas are fully differentiated neuronal tumours that do not contain immature elements and potentially occur anywhere along the peripheral autonomic ganglion sites.
On imaging, usually, they present as well-defined solid masses and can be quite large at presentation. Generally, they a...
A gastric duplication cyst is a rare congenital foregut duplication cyst affecting the stomach. It accounts for less than 10% of all gastrointestinal duplications. The most common site of gastrointestinal tract duplication cysts (GTDC's) are the ileum, followed by oesophagus, large bowel and jej...
Gastroschisis refers to extra-abdominal herniation (evisceration) of fetal or neonatal bowel loops (and occasionally portions or the stomach and or liver) into the amniotic cavity through a para-umbilical abdominal wall defect.
The estimated incidence is at around 1-6 per 10,000...
The causes of generalised increased bone density in paediatric patients can be divided accodring to broad categories of cause :
dense metaphyseal bands
cortex and flat bones may also be sligh...
The Gerbode defect describes a rare abnormal left-to-right shunt between the left ventricle and right atrium through a defect in the atrioventricular septum, usually congenital in aetiology.
Gerbode defects are rare congenital cardiac anomalies, and are thought to account for less...
Germinal matrix haemorrhages, also know as periventricular-intraventricular haemorrhages (PVIH), correspond to the most common type of intracranial haemorrhage in neonates and are related to a perinatal stress affecting the highly vascularised subependymal germinal matrix. The majority of cases ...
Grading of germinal matrix haemorrhage has taken several forms over the years. The most commonly used system is the sonographic grading system proposed by Burstein, Papile et al.
restricted to subependymal region/germinal matrix which is seen in the caudothalamic groov...
Ghost vertebra is a sign, that is generally used synonymously with bone-within-a-bone vertebra, and as such, the causes form a subset of those causing bone within a bone appearance 2:
Thorotrast administration: bone within a bone appearance due to temporary growth arrest 1
Glutaric aciduria type 1 is a leukodystrophy that can be subclassified as an organic acidopathy. It has a highly variable clinical presentation, and laboratory investigations are not always diagnostic. Imaging, therefore, has an important role to play as the MRI features can be characteristic.
Glycogen storage disease (GSD) refers to a number of syndromes which are characterised by a defect in synthesis, metabolism or storage of glycogen.
There are many types of GSD:
type I: von Gierke disease
type II: Pompe disease
type III: Cori or Forbes disease
type IV: Andersen di...
Goldenhar syndrome (also known as oculo-auriculo-vertebral spectrum (OAVS), Goldenhar-Gorlin syndrome or facio-auriculo-vertebral dysplasia) is a complex congenital anomaly characterised by abnormalities of the ears, eyes and vertebrae.
The estimated incidence is at 1 in 3000-500...
Gomez-Lopez-Hernandez syndrome, also known as cerebellotrigeminal-dermal dysplasia, is a rare phakomatosis characterised by rhombencephalosynapsis, parietal-occipital scalp alopecia, brachycephaly, facial malformations and trigeminal anesthesia.
History and etymology
It is named after Manuel ...
Gonadal dysgenesis refers to a spectrum of anomalies with abnormal development of the gonads. It falls under the even broader group of disorders of gender development.
In many cases the gonads are replaced by fibrous tissue.
complete gonadal dysgenesis (CGD) / Swyer syndro...
Gonadoblastomas are uncommon sex cord / stromal tumours. They are associated with disorders of sexual development (previously known as "intersex disorders").
The vast majority are found <30 years of age. Most are discovered in the perinatal period. May occur in phenotypic males or...
The causes of gracile bones can be recalled with the following mnemonic:
M: muscular dystrophy, e.g. Duchenne muscular dystrophy
R: rheumatoid arthritis (juvenile RA)
O: osteogenesis imperfecta
D: dysplasia, e.g. Marfan syn...
The Graf method for ultrasound classification system for developmental dysplasia of the hip (DDH) in infants, combines both alpha and beta angles. There are a number of additional subdivisions, which are often not used clinically.
As a general rule, the alpha angle determines the type and in s...
Granulocytic sarcoma (also called myeloid sarcoma and chloroma) is a rare neoplasm comprised of myeloid precursor cells.
It can occur in association with:
acute myeloid leukaemia (AML)
chronic myeloid leukaemia (CML)
other myeloproliferative disorders such as
myelofibrosis with myeloid meta...
Greenstick fractures are incomplete fractures of long bones and are usually seen in young children, more commonly less than 10 years of age. They are commonly mid-diaphyseal, affecting the forearm and lower leg. They are distinct from torus fractures.
Greenstick fractures ...
The grey matter heterotopias are a relatively common group of conditions characterised by interruption of normal neuronal migration from near the ventricle to the cortex, thus resulting in "normal neurons in abnormal locations" 2. They are a subset of disorders of cortical formation 3-4.
Growth arrest lines, also known as growth resumption lines, Harris lines or Park lines, are alternating transverse rings of sclerosis at the metaphysis of a long bone.
The radiographic finding occurs from alternating cycles of osseous growth arrest and growth resumption. This appears...
Haematuria in a child is evaluated differently than in an adult in two main respects:
there is a lower likelihood of a malignancy (renal or bladder) causing the haematuria
preference is given to nonionizing radiation
Haematuria can be considered in three main forms:
Haemolytic uraemic syndrome (HUS) is a multisystem thrombotic microangiopathic disease characterised by the triad of renal failure, haemolytic anaemia and thrombocytopenia. It is the most common cause of renal failure in infancy and childhood requiring dialysis.
There are two forms of this syn...
Haemophagocytic lymphohistiocytosis (HLH), also known as macrophage activation syndrome, is a nonmalignant disorder of immune regulation characterised by overproduction of cytokines and diminished immune surveillance. It may affect multiple organs and is one of few entities which demonstrate his...
Hereditary angiopathy with nephropathy, aneurysms, and muscle cramps (HANAC) syndrome is an autosomal dominant monogenic COL4A1-related disorder.
The exact prevalence is unknown.
The cardinal features of HANAC syndrome are helpfully described in the name of...
Hand-foot-and-mouth disease is a viral illness that manifests as vesicular eruptions on the hands and feet as well as painful ulcers of the oral mucosa. Symptoms usually resolve spontaneously in 7-10 days.
In most cases, there is a prodrome of fever, vomiting, diarrhoea, anorexia, and malaise.
The harlequin eye deformity may be seen in unilateral (plagiocephaly) or bilateral (brachycephaly) coronal suture synostosis, and refers to the elevation of the superolateral corner of the orbit.
The term harlequin eye derives from the appearance of the eyes on a harlequin mask with their exagg...
Harrison's sulcus or Harrison's groove refers to a groove at the lower end of the rib cage seen in young children / infants with abnormally weak bones (e.g. rickets) or chronic respiratory disease (e.g. severe asthma). The lower chest is drawn in with flaring of the rib margin. The exact cause i...
The haystack sign on chest x-rays in paediatric patients is indicative of pneumomediastinum. The paediatric heart is surrounded above and below with gas, giving it an appearance of a haystack from Monet's paintings.
The Heiner syndrome is a rare form of primary pulmonary haemosiderosis associated with an allergy to cow's milk. The syndrome includes:
rectal blood loss with hypochromic microcytic anaemia
pulmonary infiltrates (often recurrent)
Hemiconvulsion-hemiplegia epilepsy syndrome (HHE) is a clinical syndrome of infancy or early childhood that is associated with seizures, cerebral hemiatrophy and transient or permanent epilepsy.
It refers to the characteristic holohemispheric global atrophy of one hemisphere, that is independen...
Hemihyperplasia, also known as hemihypertrophy, is asymmetry in size between the right and left of the body, more than can be attributed to normal variation.
Hemihyperplasia is more scientifically correct than hemihypertrophy as the cells are hyperplastic rather than hypertrophied ...
Hemimegalencephaly is a rare congenital disorder of cortical formation with hamartomatous overgrowth all or a part of a cerebral hemisphere. This results from either increased proliferation or decreased apoptosis (or both) of developing neurons 2.
Hemimegalencephaly is a cryptogen...
Hepatic mesenchymal hamartoma is an uncommon benign hepatic tumour. Some authors even consider this to be a developmental anomaly rather than a cystic neoplasm 9,12.
It typically occurs in children and neonates, with most cases presenting within the first two years of life 3. Ther...
Hepatoblastoma is the most common primary malignant liver tumour in children under four years of age who usually present with painless abdominal mass and raised AFP. It is tumour of embryonic origin.
Most cases are seen during the first 18 months of life and diagnosis in adulthood...
Although hepatoblastomas can be histologically classified into a variety of sub types, it is important to remember that with the possible exception of small cell undifferentiated sub type, prognosis is independent of histology when adjusted for stage gender and age 1.
As expected there are a number of different staging systems for hepatoblastoma.
PRETEXT grouping system of paediatric liver tumours
not specific to hepatoblastoma; used in all paediatric liver tumours
Intergroup staging system
specific for hepatoblastoma (see below)
Hereditary connective tissue diseases are a group of connective tissue disease that have a degree of inheritance risk. They include :
Marfan syndrome - genetic disease causing abnormal fibrillin
Ehlers-Danlos syndrome - progressive deterioration of collagen and affects joints, heart v...
Herpes simplex (HSV) encephalitis is the most common cause of fatal sporadic fulminant necrotizing viral encephalitis and has characteristic imaging findings.
Two subtypes are recognised which differ in demographics, virus and pattern of involvement. They are 1:
neonatal herpes encephalitis
Heterotaxy syndrome or situs ambiguus (also commonly, but etymologically less correctly, spelled situs ambiguous) is a disturbance in the usual left and right distribution of the thoracic and abdominal organs which does not entirely correspond to the complete or partial mirror image.
It occurs ...
The Hilgenreiner line is a line drawn horizontally through the inferior aspect of both triradiate cartilages. It should be horizontal, but is mainly used as a reference for Perkin line and measurement of the acetabular angle.
Use of this line with the other lines and angles is used to diagnose ...
Hindfoot valgus refers to malalignment of the hindfoot in which the mid-calcaneal axis is deviated away from the midline of the body.
On the DP view, this results in an increase in the angle between the mid-calcaneal axis and the mid-talar axis (talocalcaneal angle) 1.
Despite abduction of th...
Hindfoot varus describes a relatively varus position of the calcaneus which is adducted and rotated under the talus. This is best appreciated on a weightbearing DP foot radiograph as a relative reduction in the angle formed between the mid-talar and mid-calcaneal axes (the talocalcaneal angle).
Hindfoot equinus describes abnormal plantarflexion (calcaneotibial angle >90°) of the foot that occurs in the hindfoot. It occurs in congenital talipes equinovarus and congenital vertical talus.
Hirschsprung disease is the most common cause of neonatal colonic obstruction (15-20%). It is commonly characterised by a short segment of colonic aganglionosis affecting term neonates, especially boys.
Hirschsprung disease affects approximately 1:5000-8000 live births. In short ...
Hoffa's fat pad herniation is defined as herniation of infrapatellar fat through a defect in the lateral retinaculum. It is an uncommon cause of an anterolateral knee mass often detected at the fully flexed knee 1.
Mainly occurs in preschool-aged and young children as a p...
Holoprosencephaly (HPE) is a rare congenital brain malformation resulting from incomplete separation of the two hemispheres.
Classically three subtypes have been recognised, however additional entities are now included in the spectrum of the disease. The three main subtypes, in order of decreas...
Humeral condyle fractures represent fractures through the medial or lateral distal humeral condyles.
Type I: Absent or minimal femoral head changes.
A: deformity of the femoral head with intact physis.
B: deformity of the femoral head with premature physeal closure.
Type III: Pseudarthrosis of the femoral neck.
A:Complete destruction of the capital femoral epiphysis wit...
Hurler syndrome is one of the mucopolysaccharidosis (MPS type I).
It carries an autosomal recessive inheritance and manifests in the first years of life. It is clinically characterised by mental retardation, corneal clouding, deafness and cardiac disease, with death resulting in first decade of...
Hutchinson syndrome is limping and irritability due to skeletal metastases from neuroblastoma.
It should not be confused with:
History and etymology
Described by Sir Robert Grieve Hutchison (1871-1960),...
A hybrid lesion in paediatric chest radiology refers to a combination of a congenital pulmonary airways malformation (CPAM) and a pulmonary sequestration (most commonly extralobar). It falls under a type of bronchopulmonary foregut malformation. Due to more sophisticated imaging, they are increa...
Hydranencephaly is a rare encephalopathy that occurs in-utero. It is characterised by destruction of the cerebral hemispheres which are transformed into a membranous sac containing cerebrospinal fluid and the remnants of cortex and white matter 1.
Porencephaly is considered a less severe degree...
Hydrocoele of the canal of Nuck is a rare condition in female children caused by a failure of complete obliteration of the canal of Nuck 1. The canal of Nuck is an abnormal patent pouch of peritoneum extending anterior to the round ligament of the uterus into the labia majora 2. Incomplete oblit...
Grading systems of hydronephrosis have been devised to communicate the degree of upper collecting system dilatation. The most common system used (Society of Fetal Ultrasound, SFU) was originally designed for grading neonatal and infant hydronephrosis:
no dilatation, calyceal walls are ...
Hypertrophic pyloric stenosis can be characterised in ultrasound studies by the measurements of the hypertrophic muscle. Although the criteria can vary from publication to publication, an easy way to keep in mind those values is remembering the first digits of the number "pi", also represented b...
Hypervitaminosis A results from an excess of vitamin A. It usually manifests in children, and one recognised cause is administration from 13-cis retinoic acid for treatment of cancers such as neuroblastoma.
Manifestations can differ depending on whether it is an acute or chronic exce...
Hypophosphatasia refers to a rare metabolic disorder characterised by deficient serum alkaline phosphatase activity. The effects of hypophosphatasia are primarily seen in the skeletal system. The condition has marked variation in clinical expression (see subtypes).
The true incide...
Hypoplastic left heart syndrome (HLHS) is a cyanotic congenital cardiac anomaly where affected individuals can have profound cyanosis and cardiac failure.
It is one of the commonest causes for a neonate to present with congestive cardiac failure and the 4th most frequent cardiac anomaly to mani...
Hypovitaminosis A results from inadequate intake of vitamin A, fat malabsorption, or liver disorders and produces a variety of epithelial alterations.
The World Health Organization currently estimates that 45-122 countries have a vitamin A deficiency of public health significanc...
Scurvy (also known as Barlow disease in infants) is a condition characterised by an increased bleeding tendency and impaired collagen synthesis resulting in osteoporosis and impaired wound healing. It is caused by a dietary lack of vitamin C (ascorbic acid).
Scurvy in adults is ra...
IgA vasculitis (formerly known as Henoch-Schonlein purpura (HSP)) is a type of non-thrombocytopenic immune-mediated small vessel acute leukocytoclastic vasculitis.
It tends to occur in the paediatric population (peak incidence 3-10 years) 3.
In order to differentiate from other types of vascul...
Ileal atresia is a congenital abnormality where there is significant stenosis or complete absence of a portion of the ileum. There is an increased incidence in those with chromosomal abnormalities.
This article will focus on ileal atresia alone but bear in mind that some cases correspond to jej...
Incomplete fractures are a heterogeneous group of fractures that predominantly occur in the long bones of paediatric patients. Rang 1 describes a continuum of fractures that occur with increasing longitudinal force applied along the length of the bone. At the point where force exceeds the struct...
Incomplete hippocampal inversion describes the situation where the normal inversion of the hippocampus fails to happen during development.
Incomplete hippocampal inversion is the most correct description of this finding. Hippocampal malrotation is a term used by some authors 1 alth...
A generalised acceleration in bone maturation can result from a number of aetiological factors. They include:
idiopathic isosexual precocious puberty
hypothalamic or parathalamic lesion with sexual precocity: e.g.
Infantile cervical ligament oedema can typically be seen when infants have suffered accidental or abusive head and neck trauma. The finding is best seen on sagittal STIR images.
The posterior ligamentous complex refers to the ligamentum flavum and interspinous ligaments. The anteri...
Infantile haemangiomas are benign vascular neoplasms that correspond to the most common tumours of infancy. They virtually can occur anywhere, but the majority has a head and neck distribution. Characteristic growth and subsequent involution observed during the early childhood is the usual natur...
Infantile hepatic haemangiomas (IHH) are a liver lesion composed of large endothelial-lined vascular channels seen in fetuses and neonates. It should not be confused with a hepatic epithelioid haemangioendothelioma, which occurs in older patients.
Those benign tumours were previous...
Ingested foreign bodies in children are common as the world is a curious place to young children, who will put anything and everything into their mouth, and will often inadvertently swallow.
The usual practice is for plain films of the chest/abdomen to identify a foreign body.
Innominate artery compression syndrome, also known as brachiocephalic artery compression syndrome, is a rare cause of tracheal stenosis that occurs in the paediatric population.
It can only occur in the presence of an aberrantly positioned thymus that forces the aortic arch or innomi...
Interrupted aortic arch (IAA) is an uncommon congenital cardiovascular anomaly where there is a separation between the ascending and descending aorta. It can either be complete or connected by a remnant fibrous band. An accompanying large ventricular septal defect (VSD) and/or patent ductus arte...
Intestinal failure is when a patient's native bowel is unable to digest and absorb the food, electrolytes and fluids needed for normal growth and development.
This often includes intractable diarrhoea, weight loss, dehydration, electrolyte imbalance, and malnutrition.
Intestinal malrotation is a congenital anatomical anomaly that results from an abnormal rotation of the gut as it returns to the abdominal cavity during embryogenesis.
Although some individuals live their entire life with malrotated bowel without symptoms, the abnormality does predispose to mid...
Intestinal nonrotation is a congenital anomaly of the intestines that results in the small bowel occupying the right side of the peritoneal cavity and the colon predominantly on the left.
It is sometimes thought of as a subtype of intestinal malrotation.
Nonrotation is estimated ...
Intestinal transplantation is a surgical treatment for intestinal failure. It is one of the most rarely performed transplant procedures performed, exclusively involving the transplantation of donor small bowel to a recipient, with an ileostomy formation.
Due to the high risk of complications w...
Intra-abdominal calcification in a neonate can be caused by a number of pathologies that cause calcification within the peritoneal space or within organs.
The commonest cause is meconium peritonitis which is the result of aseptic peritonitis secondary...
Intracranial cystic lesions in the perinatal period can carry a relatively wide differential which includes:
Supratentorial cystic lesions
choroid plexus cyst
Intramembranous ossification describes the process of ossification from mesenchymal cells (stem cells) without a cartilaginous template and is involved in the healing process of fractures. The stages of intramembranous ossification osteogenesis are as follows:
mesenchymal cells differentiate in...
Intraventricular haemorrhage of the newborn is a distinct entity and considered separately from intraventricular haemorrhage (IVH) in adults.
In neonates, IVH is the result of germinal matrix haemorrhage, which ruptures through the ependymal lining and into the lateral ventricles.
Intussusception occurs when one segment of bowel is pulled into itself or a neighbouring loop of bowel by peristalsis. It is also known as bowel telescoping into itself.
It is an important cause of an acute abdomen in children and merits timely ultrasound examination and reduction to preclude s...