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 mucopolysaccharidoses (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 the first decad...
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...
Hydrocele 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 oblite...
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...
Hyperuricaemia is defined as elevated levels of uric acid (≥7 mg/dL) in the blood and may be caused by either urate overproduction or underexcretion.
Patients with hyperuricaemia may be asymptomatic or have symptoms and signs relating to one of the complications of hyperu...
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...
Hypoplastic right heart syndrome is a congenital cardiac anomaly. It is characterised by an underdeveloped right side of the heart, including the right ventricle, tricuspid valve, pulmonary valve, and pulmonary arteries.
It may be present in around 1.1% of stillbirths and is rarer...
Hypospadias refers to a type of congenital malformation affecting the male external genitalia.
The estimated prevalence is ~2 (range 0.2-4.1) per 1000 live births.
The urethral meatus is abnormally positioned proximally and ventrally to its normal position.
It is thou...
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...
Imperforate hymen is a congenital condition in which the hymen lacks a normal opening.
It happens in 0.1% of the female population, usually an isolated finding.
Primary amenorrhea with cyclic lower abdominal pain during menarche age. An imperforate hymen can b...
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 are the most common head and neck tumours of infancy. They can occur virtually anywhere, but the majority are found in the head and neck regions.
This article aims to be a generic discussion of the condition, for detailed and more specif...
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...
Infectious mononucleosis (also known as glandular fever) is the term for infection with Epstein-Barr Virus (EBV). The infection classically occurs in teenagers and young adults. It usually is diagnosed clinically supported by serum testing, but also may have suggestive imaging findings.
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...
Interatrial septal aneurysm or atrial septal aneurysm (ASA) is defined as an abnormal protrusion of the interatrial septum. The exact length of the protrusion that defines an interatrial septal aneurysm varies in the literature, ranging from >11 mm to >15 mm beyond normal excursion in adults 4,5...
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
Intracranial teratomas are uncommon intracranial neoplasms, which can have a bewildering variety of components and thus a wide range of appearances. They can be divided into two broad categories, intra- and extra-axial, which differ in epidemiology and clinical presentation. Another method of cl...
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 an important cause of an acute abdomen in children and merits timely ultrasound examination and reduction to preclude significant sequelae including bowel necrosis. When o...
Intussusception reduction is a procedure performed in paediatric patients who have an ileocolic intussusception.
There are several ways that reduction can be achieved radiologically:
air-reduction under fluoroscopic guidance
water-reduction under fluoroscopic guidance
physical reduction unde...
Ischiopubic synchondrosis asymmetry is characteristic enlargement of one of the ischiopubic synchondroses. It is largely considered an anatomic variant of skeletal developmental, given that it is a common and usually asymptomatic finding.
However, some cases are thought to be symptomatic and ma...
Isolated inferior vermian hypoplasia (IIVH), also referred as part of Dandy-Walker variant (DWV), is a congenital malformation characterised by partial absence of the inferior portion of the cerebellar vermis.
The term Dandy-Walker variant was created to include those malformations...
Isomerism is a term which in general means 'mirror-image'. It is used in the context of heterotaxy and is of two types:
Mirror image of the structures on the left side of the chest along the left-right axis of the body, i.e. patients with isomeri...
Jacobsen syndrome (also known as the chromosome 11q deletion syndrome) is a rare chromosomal anomaly that results from deletion of the terminal region of chromosome 11. It results in intellectual disabilities, a distinctive facial appearance and a variety of physical problems including heart def...
The Jarcho-Levin syndrome (JLS) or spondylothoracic dysostosis is a rare autosomal recessive heterogeneous disorder that can occur with variable severity. Previously the condition spondylocostal dysostosis was also considered as part of the JLS spectrum but is now considered a distinct pathologi...
Jejunal atresia is a congenital anomaly characterised by obliteration of the lumen of the jejunum. The site of the atresia can be anywhere from the ligament of Treitz to the jejunoileal junction. There can be more than one atretic segment.
This article will focus on jejunal atresia alone but be...
Johanson-Blizzard syndrome is a disorder of ectodermal dysplasia with a wide variability in its manifestations. It is thought to have autosomal recessive inheritance.
There is a wide variability in the clinical presentation, but common features are:
low birth weight
Joubert anomaly, also known as vermian aplasia or molar tooth midbrain-hindbrain malformation, is an autosomal recessive disorder where there is a variable degree of cerebellar vermal agenesis.
When associated with anomalies of the kidneys, liver and/or eyes then the term Joubert ...
A J-shaped sella is a variant morphology of the sella turcica, whereby the tuberculum sellae is flattened, thus forming the straight edge of the "J". The dorsum sellae remains rounded and forms the loop of the "J".
Differential diagnosis for a J-shaped sella includes 1,2...
Juberg-Hayward syndrome (JHS), also known as the oro-cranio-digital syndrome, is a rare autosomal recessive syndrome characterised by the association of the following:
cleft lip and palate
minor vertebral and rib anomalies 4
horseshoe kidneys 4
Juvenile granulosa cell tumours of the ovary (JGCT) are a less common subtype of granulosa cell tumour of the ovary (~5% of cases). They are classified as ovarian sex cord / stromal tumours.
It typically occurs in premenarchal girls and young women. The mean age of presentation is...
Juvenile idiopathic arthritis (JIA), also known as juvenile rheumatoid arthritis, is the most common chronic arthritic disease of childhood and corresponds to a group of different subtypes.
The estimated incidence is ~13 per 100,000 per annum 3. By definition, symptoms must start ...
Staging of juvenile nasopharyngeal angiofibromas is performed with cross-sectional imaging and relies on the identification of local tumour extent, and invasion of adjacent spaces. For a discussion of this entity please refer to the parent article: juvenile nasopharyngeal angiofibroma.
Juvenile osteoporosis refers to osteoporosis occurring in children.
It can arise from a number of causes 1-4:
osteoporosis pseudoglioma syndrome
Juvenile polyposis syndrome, also referred as familial juvenile polyposis, is one of the polyposis syndromes and consists of hundreds of juvenile polyps.
Presentation in the second decade is most common 2.
Rectal bleeding, bowel obstruction and intussuscept...
Kabuki syndrome (Niikawa-Kuroki syndrome) is a rare polydysplasia that is thought to be more common in Japan.
Estimated incidence of 1:32,000 in Japan. Sporadically seen elsewhere in the world. The reason for the disparity in incidence is controversial.
The cause for t...
Kartagener syndrome is a subset of primary ciliary dyskinesia, an autosomal recessive condition characterised by an abnormal ciliary structure or function, leading to impaired mucociliary clearance.
The prevalence of primary ciliary dyskinesia is approximately 1 in 12,000-60,000 ...
Kasabach-Merritt syndrome, also known as haemangioma thrombocytopenia syndrome, is a rare life-threatening disease found in infants in which a rapidly growing vascular tumour is responsible for thrombocytopenia, microangiopathic haemolytic anaemia and consumptive coagulopathy.
Kasai classification is used to describe the three main anatomical types of biliary atresia.
type I: obliteration of common bile duct (patent cystic and common hepatic duct)
IIa: obliteration of common hepatic duct (patent cystic and common bile duct), sometimes with a...
Kawasaki disease is a small to medium vessel vasculitis predominantly affecting young children. It can affect any body organ but there is a predilection for the coronary vessels.
Japan has the highest incidence in the world, with an annual incidence of 300/100,000 children under t...
Kearns-Sayre syndrome (KSS), also known as oculocraniosomatic disorder, is a rare multisystem mitochondrial disorder.
The patient often presents with progressive external ophthalmoplegia 1. Neurologic symptoms develop in childhood or adolescence, usually before 20 years ...
Kernicterus, also known as chronic bilirubin encephalopathy, describes the chronic, toxic, permanent sequelae of high levels of unconjugated bilirubin on the central nervous system of infants. It is part of the spectrum of bilirubin-induced neurologic dysfunction, which also includes acute bilir...
The keyhole sign is an ultrasonographic sign seen in boys with posterior urethral valves. It refers to the appearance of the proximal urethra (which is dilated) and an associated thick-walled distended bladder which on ultrasound may resemble a keyhole.
Kirner deformity is characterised by a curvature of the distal phalynx of the 5th digit in both a palmar and radial direction.
The deformity typically presents in late childhood to early adolescence, although a mild deformity may be present at birth. Both sexes are affected, altho...
Klinefelter syndrome (KS) is a chromosomal anomaly, which in most cases is characterised by 47 chromosomes instead of the usual 46.
The estimated incidence is 0.15-0.2% of live births.
the testes are normal prior to puberty and small in post pubertal testes...
Klippel-Feil syndrome is a complex heterogeneous entity that results in cervical vertebral fusion. Two or more non-segmented cervical vertebrae are usually sufficient for diagnosis.
There is a recognised female predilection 1. Klippel-Feil syndrome has an incidence of 1:40,000-42,...
Kniest dysplasia is rare type of short limbed skeletal dysplasia.
It is thought to carry an autosomal dominant inheritance. Kniest dysplasia is one of a spectrum of skeletal disorders caused by mutations in the COL2A1 gene. This gene provides instructions for making a prote...
Köhler disease is an eponymous term referring to childhood-onset osteonecrosis of the navicular bone in the foot. Mueller Weiss syndrome is the adult counterpart of navicular bone osteonecrosis 4,5 .
It typically presents in the paediatric population (4-6 years of age) and there i...
Krabbe disease, also known as globoid cell leukodystrophy, is an autosomal recessive leukodystrophy.
Can vary and depends on the age of onset 5.
loss of developed milestones
Kump's bump is a superior convexity of the growth plate located in the anteromedial quadrant of the distal tibia physis, which is the first site of physeal fusion. Closure usually occurs at about 12-13 years of age. The Kump's bump should not to be mistaken for a fracture or abnormal physeal fus...
L-2-hydroxyglutaric aciduria is a rare organic aciduria but has characteristic MRI findings especially in the early stages 1. This can allow for early diagnosis, often prior to biochemical investigations.
As it is inherited in an autosomal recessive fashion, consanguineous marriag...
Lacuna magna, also known as the sinus of Guérin, is a congenital blind-ended pouch located dorsal to navicular fossa of penis separated by fold and both share an external common opening to external urethral meatus. This diverticulum is located above and parallel to the urethra.
Ladd bands are the most commonly encountered form of peritoneal bands in disarrangement of intestines, e.g. intestinal malrotation.
Classically they extend from the abnormally positioned caecum to peritoneum and liver, crossing the duodenum in their course. Extension, however, can in...
Langerhans cell histiocytosis (LCH) is a rare multi-system disease with a wide and heterogeneous clinical spectrum and variable extent of involvement.
Langerhans cell histiocytosis was previously known as histiocytosis X. The newer term is preferred as it's more descriptive of its...
The central nervous system (CNS) is an uncommonly involved organ system in Langerhans cell histiocytosis (LCH). Involvement of the CNS is related but distinct from involvement of the skull base or craniofacial structures, which are discussed separately in the article skeletal manifestations of L...
The skeleton is the most commonly involved organ system in Langerhans cell histiocytosis (LCH) and is by far the most common location for single-lesion LCH, often referred to as eosinophilic granuloma (EG) (the terms are used interchangeably in this article). For a general discussion of this dis...
The Lasjaunias classification, at the time of writing (mid 2016), is one of the two commonly used systems for classifying vein of Galen malformations. It relies on dividing the entity into choroidal or mural types, depending on the number and origin of feeding arteries.
Lateral epicondyle fractures are rare epicondylar fractures. They are much rarer than medial epicondyle fractures and represent avulsion of the lateral epicondyle. They are usually seen in the setting of other injuries 1-3.
Incidence typically peaks in the paediatric age group (6...
Lateral humeral condyle fractures also referred to simply as lateral condyle fractures (in the appropriate context), are relatively common elbow fractures that predominantly occur in children. They may be subtle but are hugely important to diagnose in a timely manner because if they are missed, ...
Leaky lung syndrome refers to a form of non-cardiogenic pulmonary oedema.
Pulmonary oedema due to increased capillary permeability.
Leaky lung syndrome is considered a mild form of a part of the spectrum of acute lung injury with ARDS at the other end of the...
Leg bowing in children is common and often developmental.
The differential includes:
exaggeration of normal age-related angulation changes at the knee
neonates and infants normally have varus angulation that gradually corrects within 6 months of w...
Staging of Legg-Calve-Perthes syndrome refers to x-ray abnormalities, and represents 4 phases of the disease:
stage I: early
asymmetric femoral epiphyseal size (smaller on the affected side)
apparent increased density of the femoral head epiphysis
widening of the medial joint space
Leigh syndrome, also known as subacute necrotising encephalomyelopathy (SNEM), is a mitochondrial disorder with progressive neurodegeneration that invariably leads to death, usually in childhood.
Leigh syndrome is encountered in approximately 1 in 40,000 births, although some popu...
Lennox-Gastaut syndrome is a form of refractory childhood-onset epilepsy and is often accompanied by developmental delay and psychological/ behavioural problems. An electroencephalogram (EEG) often shows a slow spike and wave pattern.
It is thought to often appear between the 2nd ...
Lenticulostriate vasculopathy also known as thalamostriate vasculopathy or mineralising vasculopathy 1, refers to the ultrasound appearance of hyperechogenic linear or branching tubular streaks in the thalami or basal ganglia of neonates.
Lenticulostriate vasculopathy has been rep...
Leptomeningeal cysts, also known as growing skull fractures, are an enlarging skull fracture that occurs near post-traumatic encephalomalacia. The term cyst is actually a misnomer, as it is not a cyst, but an extension of the encephalomalacia. Hence, it is usually seen a few months post-trauma.
Lethal omphalocele-cleft palate syndrome is, as the name suggests, characterised by the association of omphalocele and cleft palate.
Prevalence is assumed to be <1 per 1,000,000. It has been postulated that this syndrome is likely to be an autosomal recessive condition 1.
History and etymolog...
The leukodystrophies are dysmyelinating disorders which typically, although not invariably, affect children. They include:
lysosomal storage diseases
globoid cell leukodystrophy (Krabbe disease)
Leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL) is a rare inherited autosomal recessive leukodystrophy characterised by slowly-progressive pyramidal, cerebellar, and dorsal column dysfunction.
Although considered rare, the exact prevalen...
Leukoencephalopathy with calcifications and cysts, also known as Labrune syndrome, is a rare condition that consists of a triad of leukoencephalopathy, cerebral calcifications and oedematous cysts.
Leukoencephalopathy with calcifications and cysts is an extremely rare condition, w...
Liddle's syndrome is an autosomal dominant condition which inhibits the normal degradation of the ENaC sodium channel, resulting in findings that mimic Conn's syndrome (hyperaldosteronism); hypernatraemia, hypokalaemia and elevated serum bicarbonate. Typically patients are asymptomatic other tha...
The line of Klein describes a line along the superior edge of the neck of the femur. It is useful in detecting early slipped upper femoral epiphysis in adolescents. The line should normally intersect the lateral part of the superior femoral epiphysis. If the line of Klein fails to intersect the...