Neonatal pneumonia refers to inflammatory changes of the respiratory system caused by neonatal infection.
It is one of the leading causes of significant morbidity and mortality in developing countries. Neonatal pneumonia accounts for 10% of global child mortality. At the time of w...
The causes of neonatal pneumoperitoneum are different from adult pneumoperitoneum and include:
perforated hollow viscus
necrotizing enterocolitis (NEC): most common
meconium ileus in cystic fibrosis
intestinal atresia or web
peptic ulcer disease
Neonatal pneumothorax describes pneumothoraces occurring in neonates. It is a life-threatening condition, associated with high morbidity and mortality. The diagnosis is a challenge especially when the amount of air is small and may accumulate along the anterior or medial pleural space.
Causes of neonatal distress can be broadly split into intrathoracic, extrathoracic and systemic:
respiratory distress syndrome (RDS)
transient tachypnea of the newborn (TTN)
meconium aspiration syndrome
bronchopulmonary dysplasia (BPD)
patent ductus arteriosus (PDA)
The supine chest view of the neonatal patient is a common radiographic examination when examining preterm patients 1. Although not overall technically demanding, the radiographer should allocate time to ensure little to no repeats are required.
Research surrounding the technical evaluation and ...
Nephroblastomatosis refers to diffuse or multifocal involvement of the kidneys with nephrogenic rests (persistent metanephric blastema).
Nephrogenic rests are found incidentally in 1% of infants.
Nephrogenic rests are foci of metanephric blastema that persist beyond 36...
Nephrotic syndrome results from loss of plasma proteins in the urine and characterized by hypoalbuminemia, hyperalbuminuria, hyperlipidemia, and edema. It may be caused by primary (idiopathic) renal disease or by a variety of secondary causes.
Patients present with marked...
Neuhauser sign refers to a soap bubble appearance seen in the distal ileum in cases of meconium ileus, related to the air mixed with meconium. It may be seen with barium enema if contrast passes beyond the ileocecal valve or with small-bowel follow-through.
Although classically described with m...
The neurenteric canal or canal of Kovalevsky is the transient communication of the amnion through notochordal canal to the yolk sac during notochordal formation at day 16-17.
Abnormalities during this stage produce the neurenteric cyst spectrum.
Neuroacanthocytosis syndromes (NAS), previously known collectively as Levine-Critchley syndrome, are characterized by basal ganglia degeneration, acanthocytosis, and normal serum lipoprotein.
There are four core NAS:
McLeod syndrome (MLS)
Huntington disease-like ...
Neuroblastic tumors 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 la...
Neuroblastomas are tumors of neuroblastic origin. Although they may occur anywhere along the sympathetic chain, the vast majority arise from the adrenal gland.
They represent the most common extracranial solid childhood malignancy and are the third commonest childhood tumor after leukemia and b...
Image-defined risk factors are imaging features seen at the time of neuroblastoma diagnosis that confer a poorer prognosis. The International Neuroblastoma Risk Group (INRG) suggested an update (2009) to the neuroblastoma staging with a list of features that, if present, upstages a patient with ...
There are two methods of neuroblastoma staging, one that is based on post-operative patients (INSS) and one developed for pre-treatment patients (INRGSS).
International Neuroblastoma Staging System (INSS)
This staging system is for post-operative patients and mainly for prognosis 1:
Both neuroblastoma and Wilms tumor 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 structur...
Neurocristopathy syndromes encompasses a group of conditions united by abnormal migration, differentiation, division or survival of neural crest cells 1.
neurofibromatosis type I (NF1)
Neuroendocrine cell hyperplasia of infancy (NEHI) is a rare interstitial lung disease of childhood that typically presents in the first year of life.
Neuroendocrine cell hyperplasia of infancy was previously reported as persistent tachypnea of infancy until the disease was found to...
Neurofibromas are benign peripheral nerve sheath tumors usually solitary and sporadic, however, there is a strong association with neurofibromatosis type 1 (NF1). These tumors present as a well-defined hypodense mass with minimal or no contrast enhancement on CT. On MRI, they usually are T1 hypo...
Neuronal intranuclear hyaline inclusion disease (NIID) is a slowly progressive neurodegenerative disease characterized by eosinophilic hyaline intranuclear inclusions in the central and peripheral nervous system, and also in the visceral organs.
Originally considered as primarily...
Niemann-Pick disease (NPD) is actually a collection of a number of distinct autosomal recessive lysosomal storage diseases. They are divided into two groups of two based on the underlying metabolic deficiency:
deficiency of acid sphingomyelinase 1,3,4
Niemann-Pick disease type A (NPD-A)
Niemann-Pick disease type B (NPD-B), along with Niemann-Pick disease type A (NPD-A), is an autosomal recessive disorder due to acid sphingomyelinase deficiency resulting in abnormal storage of sphingomyelin.
Common manifestation of NPD-B includes hepatosplenomegaly, thrombocytopenia, and variab...
Niemann-Pick disease type c (NPD-C or just NPC) is an autosomal recessive lysosomal storage disorder classed under Niemann-Pick disease on account of clinical similarities, namely hepatosplenomegaly and variable involvement of the central nervous system.
NPD-C is inherited as an ...
Non-decussating retinal-fugal fiber syndrome (NRFFS), also referred to as achiasma, is the isolated congenital absence of optic chiasm with unremarkable rest of the optic pathway and midline structures. Clinically, it typically presents as seesaw nystagmus since childhood. Diagnosis is usually m...
Non-ossifying fibromas (NOF) are the most common type of non-neoplastic fibrous bone lesion and are a larger version (>3 cm) of a fibrous cortical defect; both are encompassed by the term fibroxanthoma or metaphyseal fibrous defect.
Non-ossifying fibromas are very common in childr...
Non-tuberculous mycobacterial adenitis refers to lymphadenopathy due to mycobacterial infection other than M. tuberculosis.
Most cases occur in immunocompetent children younger than 5 years of age.
Patients present with a firm, painless mass that enlarges ...
Noonan syndrome (NS) is a genetically and phenotypically heterogeneous non-aneuploidic congenital RASopathy. Affected individuals can bear some clinical features similar to that of Turner syndrome.
The estimated incidence is at ~1 in 1000-2500 10. As individuals have normal numbe...
Noonan syndrome with multiple lentigines, previously known as LEOPARD syndrome (LS), is a rare autosomal dominant RASopathy that has many similarities to Noonan syndrome.
Despite a change in formal name, the 'LEOPARD' acronym is still useful to summarize the clinical feat...
The normal size of kidneys in children will naturally depend on the age and size of the child. Based on the children's ages normal average renal length on ultrasound are as follows:
0 to 2 months: 5 cm (approximately 2 inches)
2 months to 6 months: 5.7 cm
6 months to 1 year: 6.2 cm (2.5 inche...
After normal myelination in utero, myelination of the neonatal brain is far from complete. The first myelination is seen as early as the 16th week of gestation, in the column of Burdach, but only really takes off from the 24th week 1. It does not reach maturity until 2 years or so. It correlates...
This article lists examples of normal imaging of the pediatric patients divided by region, modality, and age.
premature (27 weeks): example 1
neonate: example 1 (lateral decubitus)
6-year-old: example 1
12-year-old: example 1
CT chest: exampl...
Norrie disease is a rare X-linked inherited cause of congenital bilateral blindness. It can present with a retinal mass (pseudoglioma) and cataracts. It is associated with developmental delay and hearing loss.
The nuchal fold is a normal fold of skin seen at the back of the fetal neck during the second trimester of pregnancy. Increased thickness of the nuchal fold is a soft marker associated with multiple fetal anomalies, and is measured on a routine second trimester ultrasound.
Occipital horn syndrome is a rare X-linked disorder of copper metabolism resulting in connective tissue abnormalities. Menkes disease is the severe form of this disease, with patients rarely surviving past 3 years of age. Occipital horn syndrome (also known as X-linked cutis laxa or Ehlers Danl...
Octreotide scintigraphy uses 111In-labeled octreotide which is a somatostatin analog; it is also known as an OctreoscanTM, a brand name for 111In-labeled pentetreotide; pentetreotide is a DTPA-conjugated form of octreotide, originally manufactured by Mallinckrodt Nuclear Medicine LLC, which now ...
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 OEIS complex refers to the combined occurrence of:
bladder exstrophy / cloacal exstrophy
an imperforate anus
and spinal anomalies: e.g
The estimated occurrence is at around 1-200,000 to 400,000 live births 1,8.
Esophageal atresia refers to an absence in the continuity of the esophagus due to an inappropriate division of the primitive foregut into the trachea and esophagus. This is the most common congenital anomaly of the esophagus.
It is thought to occur in ~1:3,000-4,500 live births 3...
Esophageal atresia is closely related to tracheo-esophageal fistula and can be divided into1:
type A: isolated esophageal atresia (8%)
type B: proximal fistula with distal atresia (1%)
type C: proximal atresia with distal fistula (85%)
type D: double fistula with intervening atresia (1%)
Esophageal duplication cysts are a type of congenital foregut duplication cyst.
Less common compared to other foregut duplication cysts. There may be an increased male predilection 5.
Patients are generally asymptomatic but may complain of dysphagia due to ...
The omega epiglottis is a variant configuration of the normal epiglottis in which the lateral folds are curled inwards. The configuration is not necessarily pathologic but has been associated with higher rates of laryngomalacia 3.
When seen on a lateral neck radiograph,...
The omega sign can refer to a number of different anatomical structures or signs:
omega sign (epiglottitis)
omega sign (hand bump on the precentral gyrus)
Omphaloceles, also known as exomphalos (rare plural: exomphali), are congenital midline abdominal wall defects at the base of the umbilical cord insertion, with herniation of gut (or occasionally other structures) out of the fetal abdomen.
The estimated occurrence can be up to 1:4...
Opsomyoclonus (OMS), also known as dancing eyes-dancing feet syndrome and opsoclonus-myoclonus syndrome, is a clinical syndrome which has a strong association with neuroblastoma.
The “opso-“ refers to the presence of intermittent jerky eye movements (dancing eyes) and the...
Optic pathway gliomas are relatively uncommon tumors, with a variable clinical course and usually seen in the setting of neurofibromatosis type I (NF1). Histologically the majority are pilocytic astrocytomas.
They are characterized by imaging by an enlarged optic nerve seen either on CT or MRI....
Oral-facial-digital syndromes (OFDS) are a group of rare genetic developmental disorder that affects the mouth, face, digits and also may cause some problems on the central nervous, kidney and the other organs.
Some publications have classified at least 13 forms of OFDS based on...
Orbital lymphangiomas, also known as orbital venous lymphatic malformations, are congenital benign orbital vascular malformations composed of variable venous and lymphatic components
Orbital lymphangiomas are common in children.
orbital swelling and proptos...
Ornithine transcarbamylase deficiency (OTCD) is a form of hyperammonemic encephalopathy. It can have variable levels of severity.
It is considered the most common inborn error of metabolism of the urea cycle, with an incidence of one case per 14,000 live births.
It is ...
Orthoroentgenogram is a radiographic study used to evaluate anatomic leg length and calculate leg-length discrepancies. This study utilizes a long ruler placed on the film, and three radiographs including bilateral hips, knees and ankles.
Similar studies used to evaluate true leg length include...
Osgood-Schlatter disease (OSD) is a chronic fatigue injury due to repeated microtrauma at the patellar ligament insertion onto the tibial tuberosity, usually affecting boys between ages 10-15 years.
Osgood-Schlatter disease is seen in active adolescents, especially those who jump ...
There are six ossification centers of the elbow that appear and develop in a relatively reproducible fashion, and are key to assessment of the pediatric elbow radiograph. Timing of their appearance varies in the literature but an approximation is given below. A useful mnemonic to remember the or...
Primary ossification centers present at birth
Visible on x-ray from birth:
calcaneus: 6 months in utero
talus: 7 months in utero
cuboid: 9 months in utero
metatarsals: 9 weeks in utero
phalanges: 3-10 months (proximal to distal)
Primary ossification centers developing after birth
Primary ossification centers present at birth
Visible on x-ray from birth:
metacarpal diaphyses: 9 weeks in utero
phalangeal diaphyses: 9-12 weeks in utero
Primary ossification centers developing after birth
Ossification of the carpal bones occurs in a predictable sequence, starting with th...
Ossifying renal tumor of infancy (ORTI) is a rare renal tumor.
extremely rare, <<1% of pediatric renal neoplasms (17 cases reported)
6 days - 3 months
Histology reveals spindle cells and osteoblastic cells in a calcified osteoid matrix. It is thought...
Osteochondritis dissecans (OCD) is the end result of the aseptic separation of an osteochondral fragment with the gradual fragmentation of the articular surface and results in an osteochondral defect. It is often associated with intraarticular loose bodies.
Onset is between childh...
Osteofibrous dysplasia is a benign fibro-osseous cortical lesion that occurs almost exclusively in the tibia and fibula. It is most commonly seen in the mid-diaphysis of the tibia. Some consider it synonymous with ossifying fibroma because of histological similarities, but it is generally consid...
Osteogenesis imperfecta (OI) refers to a heterogeneous group of congenital, non-sex-linked, genetic disorders of collagen type I production, involving connective tissues and bones.
The hallmark feature of osteogenesis imperfecta is osteoporosis and fragile bones that fracture easily, as well a...
The several forms of osteogenesis imperfecta (OI) have been classified, representing wide variation in appearance and severity, and clinical features vary widely not only between types but within types.
Osteogenesis imperfecta was initially classified by type according to a sche...
Osteoid osteomas are benign bone-forming tumors that typically occur in children (particularly adolescents). They have a characteristic lucent nidus less than 1.5 or 2 cm and surrounding osteosclerotic reaction, which classically causes night pain that is relieved by the use of salicylate analge...
Osteopathia striata with cranial sclerosis (OS-CS) is a clinically separate entity from osteopathia striata (Voorhoeve disease). Bony changes on their own are typically incidental and autosomal dominant, whereas OS-CS is a multisystem, X-linked dominant disorder.
OS-CS is extremel...
Osteopetrosis, also known as Albers-Schönberg disease or marble bone disease, is an uncommon hereditary disorder that results from defective osteoclasts. Bones become sclerotic and thick, but their abnormal structure actually causes them to be weak and brittle.
There are two separate subtypes o...
Osteopoikilosis is a sclerosing bony dysplasia characterized by multiple benign enostoses. It is a rare inherited benign condition incidentally found on skeletal x-rays. Its importance is predominantly in correct diagnosis so that it is not mistaken for pathology.
The bone islands...
Osteoporosis pseudoglioma syndrome is a rare autosomal recessive disease that is characterized by severe osteoporosis and blindness. This disease is frequently mistaken for osteogenesis imperfecta.
This disease is encountered in approximately 1 in 2 million births.
Oxycephaly (also known as turricephaly) is the most severe of the craniosynostoses and results from the premature closure of all sutures.
Characterized by a tower-like skull which may be associated with:
8th cranial nerve lesion
optic nerve compression
Oxygen (chemical symbol O) is one of the basic organic elements, and is a constituent of most of the known organic molecules - and therefore all lifeforms - on earth.
Oxygen is a colourless odorless diatomic gas with an atomic number 8 and atomic weight 15.999. It h...
The AP supine abdominal radiograph is a routine view when imaging the pediatric abdomen. This view may be taken alongside the PA erect and lateral decubitus views. As radiation protection is an essential consideration in pediatrics, some departmental protocols may only perform one view (either t...
The invertogram view is an additional projection to demonstrate the pediatric abdomen and is often used exclusively in characterizing anal atresia. However, as this view may be less comfortable for the patient and result in a more technically challenging examination, a more ideal alternative tec...
The lateral decubitus radiograph is an additional projection for assessing the pediatric abdomen. This view is ideal for displaying free air in the abdomen and/or if the patient is unable to lie supine 1. As radiation dose is an important consideration for pediatric imaging, the lateral decubitu...
The PA erect abdominal radiograph is the standard view for assessing air-fluid levels and free air in the pediatric abdomen. This view may be taken alongside the AP supine and lateral decubitus views. As radiation protection is an essential consideration in pediatrics, some departmental protocol...
The prone cross-table lateral view is an additional projection to demonstrate the pediatric abdomen and is a more ideal alternative to the invertogram, which may be less comfortable for the patient. This discomfort may result in a continuously crying baby, causing the puborectalis sling to contr...
The supine cross-table lateral view is an additional projection to demonstrate the pediatric abdomen. As radiation dose is an important consideration for pediatric imaging, the horizontal beam lateral view is not often performed; although this will vary based on the department.
Pediatric benign liver tumors are a relatively rare, but important group of conditions. Importantly, the commonest cause of a benign liver tumor is specific to the pediatric population. The list in descending order of frequency is:
infantile hepatic hemangioma (previously hemangioendothelioma)
A number of pediatric cardiovascular procedures are encountered when reporting pediatric imaging. They include:
Blalock-Taussig (BT) shunt
classic: end to side subclavian to ipsilateral pulmonary arterial anastomosis
modified: graft anastomosis
Sano shunt: right ventricle to...
The differential diagnosis of pediatric cervical lesions is commonly encountered in practice, unfortunately, the list is long.
Most lesions tend to be inflammatory 3:
non-tuberculous mycobacterial lymphadenitis
The anteroposterior erect chest view is ideal in younger cooperative pediatric patients (approximately 3-7 years old; this age range is only a guide). This chest view examines the lungs, bony thoracic cavity, mediastinum and great vessels.
The AP erect view is often chosen over the PA erect vie...
The horizontal beam (cross-table) pediatric lateral chest view is a modified lateral projection often utilized in populations under the age of 6 months old due to the inability of that patient to independently hold up their head.
A lateral radiograph helps confirm the presence of a...
The pediatric lateral chest view may be performed as an adjunct to a frontal chest radiograph in cases where there is diagnostic uncertainty. The lateral chest view examines the lungs, bony thoracic cavity, mediastinum, and great vessels. Lateral radiographs can be particularly useful in assessi...
In pediatric imaging, the anteroposterior supine chest x-ray is beneficial for imaging unconscious or uncooperative patients. This view is preferred in infant and neonate imaging, whilst AP erect and PA erect views are ideal for children able to cooperate in sitting or standing 1.
As radiation ...
The clavicle is a unique bone and as such it often displays unique pathology. The following is an attempt to summarize pediatric clavicle abnormalities.
Pediatric bone tumors and tumor-like lesions of the clavicle
majority of clavicular tumors are malignant
Ewing sarcoma (most common)
The pediatric curriculum is one of our curriculum articles and aims to be a collection of articles that represent the core pediatric knowledge.
Topics pertaining to pediatric radiology, including pediatric neuroradiology and fetal radiology, although there will be some cross coverag...
The pediatric cystic renal diseases are a heterogeneous group of conditions defined by the presence of kidney cysts due to hereditary or non-hereditary causes:
isolated simple cyst
cystic renal dysplasia
multicystic dysplastic kidney (MCDK)
obstructive cystic renal dysplasia
The anteroposterior elbow view for pediatrics is part of the two view elbow series, examining the distal humerus, proximal radius and ulna.
The projection demonstrates the elbow joint in its natural anatomical position allowing for adequate radiographic examination of the articula...
The horizontal beam anteroposterior elbow view for pediatrics is an alternative projection to the anteroposterior view in the elbow series, examining the distal humerus, proximal radius and ulna.
This view is ideal for patients who are unable to move their arm as per the standard ...
The horizontal beam lateral elbow view for pediatrics is an alternative projection to the lateral view in the elbow series, examining the distal humerus, proximal radius and ulna.
This view demonstrates an orthogonal view of the AP elbow and is ideal for patients who are unable to...
The lateral elbow view for pediatrics is part of a two view elbow series, examining the distal humerus, proximal radius and ulna.
The projection is the orthogonal view of the AP elbow allowing for examination of the ulna-trochlear joint, coronoid process, and the olecranon process....
Pediatric elbow radiographs are commonly encountered in the emergency department and, when approached in a systematic fashion, are not as difficult to interpret as most people think!
Check that the ossification centers are present and in the correct position. Th...
The anteroposterior forearm view for pediatrics is one of two standard projections in the forearm series to assess the radius and ulna.
This view demonstrates the elbow joint in its natural anatomical position allowing for assessment of suspected dislocations or fractures and local...
The horizontal beam lateral forearm view for pediatrics is one of two modified trauma projections in the forearm series, examining the radius and ulna.
This view is ideal for patients who are unable to move their arm as per the standard forearm positioning technique but require as...
The lateral forearm view for pediatrics is one of two standard projections in the forearm series to assess the radius and ulna.
This view allows for the assessment of suspected dislocations or fractures and localizing foreign bodies within the forearm.
However, this view should no...
The posteroanterior forearm view for pediatrics is one of two modified trauma projections in the forearm series, examining the radius and ulna.
This view is ideal for patients who are unable to move their arm as per the standard forearm positioning technique but require assessment...
The lateral hand view for pediatrics is an orthogonal view taken along with the PA view of the hand. The lateral view is used to primarily assess for foreign bodies and/or displacement of fractures/dislocations.
This view is useful in assessing suspected dislocations, fractures or ...
The oblique hand view for pediatrics is part of a two view series examining the phalanges, metacarpals, carpal bones and distal radioulnar joint.
This view is useful in assessing suspected dislocations or fractures, localizing foreign bodies or evaluating juvenile idiopathic/rheuma...
The posteroanterior hand view for pediatrics is part of a two view series examining the phalanges, metacarpals, carpal bones and distal radioulnar joint.
This view is useful in assessing suspected dislocations or fractures, localizing foreign bodies or evaluating juvenile idiopath...
The frog leg lateral view is a special radiographic of the pelvis to evaluate the hip. Some departments will perform this routinely instead of the AP pelvis view to reduce exposure and maintain high diagnostic accuracy 1.
Bilateral examination allows for better visualization of the...