An absent septum pellucidum may rarely be an isolated finding, or more commonly be seen in association with a variety of conditions.
The septum pellucidum is partly or entirely absent in 2 or 3 individuals per 100,000 in the general population.
An absent septum pelluc...
Human alpha fetoprotein (AFP) elevation may occur in a vast number of conditions:
liver tumours (hepatocellular carcinoma, hepatoblastoma)
<10 ng/ml is within normal limits
>20 ng/ml is above normal limits but has low specificity for tumour since it may occur in a setting of diffuse liver inj...
Airway foreign bodies in children are potentially fatal, which is why immediate recognition is important. Unfortunately, delayed diagnosis is common.
Children under the age of four years are at increased risk of foreign body (FB) aspiration, with a slight male predominance 1.
Alternating radiolucent and radiodense metaphyseal lines can be seen with a number of conditions and the differential diagnosis is wide:
growth arrest lines
rickets: especially those on prolonged treatment, e.g. vitamin D dependent rickets
Anoxic brain injury, also known as global hypoxic-ischaemic injury, is seen in all age groups (from antenatal to the elderly) as a result of numerous aetiologies. The pattern of injury depends on a number of factors including:
age of the patient (brain maturity)
neonatal hypoxic-ischaemic ence...
Anterior vertebral body beaking occurs in a number of conditions and may eminate from the central portion or the lower third of the vertebral body.
Morquio syndrome 1 (middle for Morquio)
Hurler syndrome 2
Asplenia syndrome (also known as right isomerism or Ivemark syndrome) is a type of heterotaxy syndrome.
There is an increased male predilection. Asplenia syndrome is usually diagnosed in neonates.4
In contrast to polysplenia syndrome, most patients die bef...
Paediatric benign liver tumours are a relatively rare, but important group of conditions. Importantly, the commonest cause of a benign liver tumour is specific to the paediatric population. The list in descending order of frequency is:
infantile hepatic hemangioma (previously haemangioendotheli...
Bent bone dysplasias are a class of dysplasia included in a 2010 classification of genetic skeletal disorders 1.
kyphomelic dysplasias, a diverse class, including
congenital bowing of the long bones
cartilage-hair hypoplasia (CHH; metaphyseal d...
Birth trauma relates to those conditions caused by both physical/mechanical and hypoxic injuries.
Birth trauma occurs in ~5 per 1000 births 2.
Blalock-Taussig shunt, also known as Blalock-Thomas-Taussig shunt, is a palliative procedure designed to increase pulmonary arterial blood flow in patients with right ventricular outflow tract obstruction (e.g. tetralogy of Fallot) or during initial staged repair of hypoplastic left heart syndro...
Bone age assessment is used to radiologically assess the biological and structural maturity of immature patients from the hand and wrist x-ray appearances. It forms an important part of the diagnostic and management pathway in children with growth and endocrine disorders. It is helpful in the di...
Bone within a bone is a descriptive term applied to bones that appear to have another bone within them. There are numerous causes including:
thoracic and lumbar vertebrae (neonates and infants)
growth recovery lines (after infancy)
cortical splitting and new periostitis
sickle cell d...
Bronchial atresia is a developmental anomaly characterised by focal obliteration of the proximal segment of a bronchus associated with hyperinflation of the distal lung.
On imaging, it commonly presents as a proximal focal tubular shaped opacity radiating from the hilum associated with a dista...
Cardiovascular (cardiac) shunts are abnormal connections between the pulmonary and systemic circulations. Most commonly they are the result of congenital heart disease.
Blood can either be shunted from the systemic circulation to pulmonary circulation (i.e. 'left-to-right shunt') or ...
Unfortunately the paediatric population is susceptible to malignancies. The most common entities, in overall order of frequency, are 1-4:
leukaemia/lymphoma: ~35% *
acute lymphoblastic leukaemia: 23%
Hodgkin disease: 5%
acute myelogenous leukaemia: 4%
central nervous system malignancies: ~2...
Chronic suppurative lung disease (CSLD) refers to a group of conditions which includes:
primary ciliary dyskinesia
This term is usually used in the context of paediatric patients.
COL4A1-related disorders are a group of autosomal dominant disorders caused by a mutation in the COL4A1 gene.
The exact prevalence is unknown, but the group of disorders is considered to be under-recognised, especially asymptomatic variants 1.
The clinical ...
Colpocephaly is a descriptive term for a disproportionate prominence of the occipital horns of the lateral ventricles. It can result from a wide range of congenital insults.
Patients may present with motor abnormalities, cognitive deficit, visual abnormalities, and seizur...
Congenital limb amputations are a limb anomaly that usually occur due to disruption of vascular supply.
Congenital amputations occur in 0.5 (range 0.03-1) per 1000 live births 2.
Slightly more common in the upper limb (60%) than in the lower limb (40%) 2.
Congenital renal anomalies comprise of vast spectrum of pathologies and include:
congenital renal hypoplasia
congenital cystic renal disease
infantile polycystic renal disease: autosomal recessive polycystic kidney disease (ARPKD):...
Coronal vertebral cleft refers to the presence of a radiolucent vertical defect on a lateral radiograph.
It is most often seen in premature male infants 1,3. As they can occur as part of normal variation (especially in the lower thoracic-upper lumbar spine of premature infants) ...
A number of entities can present as cyanotic congenital heart disease. These can be divided into those with increased or decreased pulmonary vascularity (pulmonary plethora):
increased pulmonary vascularity
total anomalous pulmonary venous return (TAPVR) (types I and II)
transposition of the ...
The differential diagnosis of a cystic mass adjacent to the angle of mandible includes:
2nd branchial cleft cyst
lymphatic malformation (lymphangioma)
from metastatic squamous cell carcinoma
from metastatic papillary thyroid cancer
A generalised retardation in skeletal maturation has different causative or aetiological factors, these can be classified as follows:
chronic ill health
congenital heart disease (especially cyanotic)
chronic renal disease
inflammatory bowel disease
malnutrition: failure to thrive (FTT)
The differential diagnosis of dense metaphyseal bands is wide.
chronic anaemia, e.g. sickle cell disease, thalassemia
chemotherapy, e.g. methotrexate
growth acceleration lines following growth arrest due to systemic illness or stress in infancy or childhood, e....
The double bubble sign is seen in infants and represents dilatation of the proximal duodenum and stomach. It is seen in both radiographs and ultrasound, and can be identified antenatally 2.
Causes include 1,2:
Epicondyle fractures are common injuries in children. They represent 10% of all elbow fractures in children and usually occur in boys after a fall on an outstretched arm.
Medial epicondyle fractures comprise most of these injuries. They can usually be treated with splinting and early physiother...
Ewing sarcoma family of tumours (ESFT) are a group of small round blue cell tumours that are closely histogenetically related, all demonstrating non-random t(11;22)(q24;q12) chromosome rearrangement resulting in the formation of the EWS-ETS fusion gene 1-3. They include:
Ewing sarcoma of bone
Although rare, a number to tumours may be diagnosed antenatally. These fetal tumours are a diverse and a unique group of conditions, and include:
neuroblastoma: most common tumour overall
head and neck teratoma/epignathus
Fibrous hamartoma of infancy is a rare benign tumour of the subcutaneous tissues seen in children. More than 90% of cases present in the first year of life with up to 25% being congenital 1.
There is a reported male:female ratio of 2:1 but the exact incidence is unknown 2.
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):
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
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...
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...
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...
Hiccups (or hiccoughs), medical term singultus (rarely used), are an unpleasant phenomenon, experienced by everyone on occasion, and usually self-limiting. However the much rarer intractable chronic form can be extremely debilitating.
Hiccups are a symptom that has probably been e...
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.
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...
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 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
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...
Juvenile osteoporosis refers to osteoporosis occurring in children.
It can arise from a number of causes 1-4:
osteoporosis pseudoglioma syndrome
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...
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...
The leukodystrophies are dysmyelinating disorders which typically, although not invariably, affect children. They include:
lysosomal storage diseases
globoid cell leukodystrophy (Krabbe disease)
Paediatric liver lesions are a heterogeneous group that include infiltrative lesions and those that demonstrate mass effect. Moreover, they may be solitary or multiple, benign or malignant:
benign liver tumours
malignant liver tumours
There are differing frequencies of both beni...
Lytic skull lesions have a relatively wide differential that can be narrowed, by considering if there are more than one lesion and whether the mandible is involved.
lytic skeletal metastases
epidermoid - scalloped border with a sclerotic rim
Paediatric malignant liver tumours are rare, some of which occur only in children but that are similar to those that occur in adults.
Malignant liver tumours account for ~1% of paediatric malignancies 2.
Broadly, any malignant liver mass can be defined as a metastasis ...
Medial epicondyle fractures represent almost all epicondyle fractures and occur when there is avulsion of the medial epicondyle. They are typically seen in children, and can be challenging to identify. Failure to diagnose these injuries can lead to significant long term disability.
Meningoceles are protrusions of the meninges through a defect or weak point in the skull or spine, usually involving the soft tissues beneath the surface of the skin. They are typically categorized into congenital, iatrogenic (e.g. following a craniotomy, sinus surgery, or as a laminectomy compl...
The metaphyseal blanch sign (a.k.a. metaphyseal blanch sign of Steel) is one of the signs seen on AP views of the adolescent hip indicating posterior displacement of the capital epiphysis.
It is a crescent-shaped area of increased density, that overlies the metaphysis adjacent to the physis on ...
Mucopolysaccharidoses (MPS) constitute a group of hereditary disorders, one of a number of lysosomal storage disorders, having in common an excessive accumulation of mucopolysaccharides secondary to deficiencies in specific enzymes (lysosomal hydrolases) responsible for degradation of mucopolysa...
Neonatal encephalopathy is a clinical syndrome referring to signs and symptoms of abnormal neurological function in the first few days of life in a neonate born at or beyond 35 weeks of gestation. It is described as difficulty with initiating and maintaining respiration, depression of tone and r...
Neonatal lines and tubes are widely used in the NICU (neonatal intensive care unit) in the management of critically ill neonates. Examples include:
nasogastric (NG) tube
endotracheal (ET) tube
central venous line
umbilical artery catheter
umbilical vein catheter
The NG tu...
Causes of neonatal distress can be broadly split into intrathoracic, extrathoracic and systemic:
respiratory distress syndrome (RDS)
transient tachypnoea of the newborn (TTN)
meconium aspiration syndrome
bronchopulmonary dysplasia (BPD)
patent ductus arteriosus (PDA)...
Neuroblastic tumours arise from primitive cells of the sympathetic system and include the following entities:
These entities represent a spectrum of disease from undifferentiated and aggressive (neuroblastoma) to the well differentiated and l...
Both neuroblastoma and Wilms tumour occur in early childhood and typically present as large abdominal masses closely related to the kidneys. Distinguishing between the two is important, and a number of features are helpful.
calcification very common: 90%
encases vascular structu...
Non-accidental injuries (NAI) represent both ethical and legal challenges to treating physicians.
Radiologists are often the first to suspect NAI when confronted with particular injury patterns, and a knowledge of these is essential if the opportunity to save a child from future neglect is not ...
Odontohypophosphatasia is the mildest form of hypophosphatasia that manifests as tooth dysplasia and/or early loss of deciduous or permanent teeth.
As with all forms of hypophosphatasia, the underlying abnormality is a mutation in the ALPL gene that encodes for tissue non-specific al...
The differential diagnosis of paediatric cervical lesions is commonly encountered in practice, unfortunately, the list is long.
Most lesions tend to be inflammatory 3:
infected branchial cle...
The clavicle is a unique bone and as such it often displays unique pathology. The following is an attempt to summarise paediatric clavicle abnormalities.
Paediatric bone tumours and tumour-like lesions of the clavicle
majority of clavicular tumours are malignant
Ewing sarcoma (most common)
Paediatric nasal cavity masses can occur within the nose or the nasopharynx. These masses are often found incidentally on imaging but can be readily apparent clinically.
The clinical features of these lesions tend to mimic upper respiratory processes and may result in del...
Paediatric renal tumours and masses are another group of diseases (just like cystic renal diseases in both the adult and child) that are bewildering in their number, nomenclature and overlapping findings.
Wilms tumour: common in older children 1-8 years old
There is a wide range of primary malignancies that results in paediatric skeletal metastases 1:
leukaemia: although not truly metastases
clear cell sarcoma: Wilms’ variant
Ewing’s sarcoma: lung metastases much more common
Neonatal hypoxic ischaemic brain injuries can manifest in different patterns of involvement depending on the severity and timing of the insult. When considering the perinatal maturation process of the brain and the severity of an insult, it is possible to understand the various manifestations.
Periosteal reaction in the paediatric population, also known as periostitis in children, is relatively common occurrence and can result from many causes.
The differential diagnosis for multiple bone periostitis include but not limited to the following:
Pneumatosis coli is a descriptive sign presenting radiographically as intramural gas limited to the colonic wall.
There are different terminologies in the medical literature, such as pneumatosis intestinalis, pneumatosis coli, and pneumatosis cystoides intestinalis. Pneumatosis in...
Posterior fossa astrocytomas, those arising either from the cerebellum or from the brainstem are most frequently seen in children. Approximately 60% of all paediatric astrocytomas are found in the posterior fossa (20% brainstem, 40% cerebellum).
Many types of astrocytoma are found in the poster...
A Pott shunt is a form of palliative surgery performed in patients with tetralogy of Fallot prior to the ability to repair the defect. It consists of a shunt formed between the descending thoracic aorta and the left pulmonary artery.
This does not relieve the right ventricular outflow obstructi...
Pre-axial polydactyly refers to polydactyly where the additional digit is towards the first digit of the hand (radial side) or foot (medially).
Pre-axial polydactyly is less common than post-axial polydactyly, with an estimated incidence of 1 in 7000.
Premature closure of a growth plate subsequently results in a shortened bone, which can occur in a number of situations.
juvenile chronic arthritis
juvenile rheumatoid arthritis
Pulled elbow (also known as nursemaid's elbow) is a subluxation of the radial head into the annular ligament, which usually spontaneously or easily reduces and rarely demonstrates abnormal radiographic features. It should be distinguished from dislocation of the radial head.
Rachitic rosary refers to expansion of the anterior rib ends at the costochondral junctions and is most frequently seen in rickets as nodularity at the costochondral junctions.
Other causes of this appearance include:
the costochondral junction is more angula...
RASopathies are a class of developmental disorders caused by germline mutations in genes that encode for components or regulators of the Ras/mitogen activated protein kinase (MAPK) pathway.
As a group, RASopathies represent one of the most common malformation syndromes, with an in...
A scalp haematoma usually occurs following an injury at delivery although they are commonly seen with head trauma.
There are three types of haematoma, which are defined by their location within the scalp, particular their location as related to the galea aponeurosis and skull pe...
The Scham sign of slipped capital femoral epiphysis is one of the subtle signs that may be seen on the AP view of an adolescent hip with early slip.
In the normal adolescent hip, an intraarticular portion of the diaphysis of the collum overlies the posterior wall of the acetabulum inferiomedial...
Sclerosing bone dysplasias comprise a heterogeneous group of disorders (skeletal dysplasias) united by the presence of sclerosis of one form or another. Some of these entities are thought to be related (e.g. osteopoikilosis, melorheostosis and Buschke-Ollendorff syndrome) 1.
Scoliosis is defined as an abnormal lateral curvature of the spine. It is quite common in young individuals and is often idiopathic and asymptomatic. In some cases, however, it is the result of underlying structural or neurological abnormalities.
By definition, a scoliosis is any lateral spina...
Short limb skeletal dysplasias are skeletal dysplasias which are charcaterised by limb shortening
Rhizomelic (proximal limb shortening)
particularly type II
Sincipital encephalocoeles are congenital herniations of cerebral parenchyma through a cranial defect. There are three main types 1,2:
frontonasal encephalocoele (~50%): more common in Asia and Latin America 4
naso-ethmoidal encephalocoele (30%): more common in North America 4
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.
The overall prevalence is estimated at ~2 per 10,000 live births 3.
The differential diagnosis of a solitary sclerotic bone lesion is heavily influenced by the age of the patient, and includes:
solitary either because no others are present or no others have been imaged
enostosis (bone island)
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.
There is often abnormal fusion of the midline embryonic neural, vertebral and mesenchymal structures.
Brain ischaemia/infarction in children and young adults can result from several causes.
cyanotic heart disease
mitral valve prolapse
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).
The overall estimated incidence is at ~1 per 2,500 to 5,000 live births 6,8. T...
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...
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
sickle cell dis...
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.
Torticollis can be acute (<1 week) or chronic ...