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Osgood-Schlatter disease

Osgood-Schlatter disease, also known as apophysitis of the tibial tubercle, is a chronic fatigue injury due to repeated microtrauma at the patellar tendon insertion onto the tibial tuberosity, usually affecting boys between ages 10-15 years. Terminology Unresolved Osgood-Schlatter disease is t...

Omphalocele

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. Epidemiology The estimated occurrence can be up to 1:4...

Nuchal fold

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. Terminology It shou...

Non-ossifying fibroma

Non-ossifying fibromas (NOF) are benign and generally self-limiting osteoclastic giant cell-rich bone tumors typically found in the metaphyses of long bones. They are classified as osteoclastic giant cell-rich bone tumors 1,2. NOFs account for the 'N' in the popular mnemonic for lucent bone les...

Neuroblastoma

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...

Nail-patella syndrome

Nail-patella syndrome, also known as Fong disease, is a rare autosomal dominant condition which results from symmetrical mesodermal and ectodermal abnormalities. Radiologically, the classic findings are the abnormal patellae and posterior iliac horns, the latter is said to be pathognomonic. Ter...

Möbius syndrome

Möbius syndrome, also known as congenital facial diplegia syndrome, is a rare congenital condition characterized by the absence or underdevelopment of the nuclei of the abducens (CN VI) and facial nerve (CN VII). Epidemiology Möbius syndrome is rare with an estimated incidence of ~1 case per 1...

Multicystic dysplastic kidney

Multicystic dysplastic kidney (MCDK) is a type of non-heritable pediatric cystic renal disease. It results in multiple cysts being formed in utero in the affected kidney. Epidemiology Unilateral incidence is estimated at 1:2500-4000. There may be a predisposition for the left kidney, a slightl...

Moyamoya disease

Moyamoya disease is an idiopathic, non-inflammatory, non-atherosclerotic progressive vasculo-occlusive disease involving the terminal supraclinoid internal carotid arteries and circle of Willis. Terminology The term moyamoya disease should be reserved for an idiopathic, sometimes familial, c...

Monteggia fracture-dislocation

Monteggia fracture-dislocations consist of a fracture of the ulnar shaft with concomitant dislocation of the radial head. The ulnar fracture is usually obvious, whereas the radial head dislocation can be overlooked, with potentially serious functional and medico-legal ramifications. Mechanism ...

Midgut volvulus

Midgut volvulus is a complication of bowel malrotation usually seen in neonates and infants. Presentation is usually with proximal small bowel obstruction and bilious vomiting. Without prompt treatment, there is a real and significant risk of small bowel ischemia, significant associated morbidit...

Congenital spinal meningocele

Congenital spinal meningoceles are developmental anomalies of meningothelial elements displaced into the skin and subcutaneous tissues. Please refer to the meningocele article for a broad overview of all types of this condition. Pathology It is a defect of the neural tube, an embryonic struc...

Meconium peritonitis

Meconium peritonitis refers to a sterile chemical peritonitis due to intra-uterine bowel perforation and spillage of fetal meconium into the fetal peritoneal cavity. It is a common cause of peritoneal calcification. Epidemiology The estimated prevalence is at ~1 in 35,000. Pathology The eti...

Intestinal malrotation

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 a malrotated bowel without associated symptoms, the abnormality does pred...

Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS)

Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) is one of many mitochondrial disorders. As mitochondria, which have their own DNA, are exclusively passed on from the mother these disorders are only inherited from the mother. On imaging, it manifests as mult...

Lymphatic malformations

Lymphatic malformations are benign lesions of vascular origin that show lymphatic differentiation. Specifically, they are vascular malformations and not vascular tumors as per the 2018 ISSVA classification of vascular anomalies 5. This article focuses on the general features of lymphatic malfo...

Lissencephaly-pachygyria spectrum

The lissencephaly-pachygyria spectrum is a useful way to describe the spectrum of diseases that cause relative smoothness of the brain surface and includes 1: agyria: no gyri pachygyria: broad gyri lissencephaly: smooth brain surface It is a basket term for a number of congenital cortical ma...

Perthes disease

Perthes disease, also known as Legg-Calvé-Perthes disease, refers to idiopathic osteonecrosis of the femoral epiphysis seen in children. It should not be confused with Perthes lesion of the shoulder. It is a diagnosis of exclusion and other causes of osteonecrosis (including sickle cell disease...

Leigh syndrome

Leigh syndrome, also known as subacute necrotizing encephalomyelopathy (SNEM), is a mitochondrial disorder with progressive neurodegeneration that invariably leads to death, usually in childhood. Epidemiology Leigh syndrome is encountered in approximately 1 in 40,000 births, although some popu...

Lead poisoning

Lead poisoning or plumbism refers to the multi-organ toxicity exerted by exposure to lead. Manifestations differ based on a myriad of features including chronicity, exposure intensity, and age. Neurologic toxicity and hematologic toxicity are common features. Clinical manifestations vary, rangin...

Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a rare multisystem disease with a wide and heterogeneous clinical spectrum and variable extent of involvement. Terminology Langerhans cell histiocytosis was previously known as histiocytosis X. The newer term is preferred as it is more descriptive of its...

Kasabach-Merritt syndrome

Kasabach-Merritt syndrome, also known as hemangioma thrombocytopenia syndrome, is a rare life-threatening disease found in infants in which a rapidly growing vascular tumor is responsible for thrombocytopenia, microangiopathic hemolytic anemia and consumptive coagulopathy. Pathology Vascular t...

Intussusception

Intussusception occurs when one segment of the bowel is pulled into itself or a neighboring loop of the 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...

Medial epicondyle fracture

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. Epidemiology...

Respiratory distress syndrome

Respiratory distress syndrome (RDS) is a relatively common condition that occurs in preterm neonates resulting from insufficient production of surfactant. Terminology RDS is also known as hyaline membrane disease (not favored as reflects non-specific histological findings), neonatal respirato...

Holoprosencephaly

Holoprosencephaly (HPE) is a rare congenital brain malformation resulting from incomplete separation of the two hemispheres. Classically three subtypes have been recognized, however additional entities are now included in the spectrum of the disease. The three main subtypes, in order of decreas...

Hirschsprung disease

Hirschsprung disease is the most common cause of neonatal colonic obstruction (15-20%). It is commonly characterized by a short segment of colonic aganglionosis affecting term neonates, especially boys. Epidemiology Hirschsprung disease affects approximately 1:5000-8000 live births. In short ...

Hereditary multiple exostoses

Hereditary multiple exostoses/osteochondromas, also known as diaphyseal aclasis, osteochondromatosis, or simply multiple osteochondromas, is an autosomal dominant condition, characterized by the development of multiple osteochondromas. Epidemiology Hereditary multiple exostoses demonstrate an ...

Herpes simplex encephalitis

Herpes simplex (HSV) encephalitis is the most common cause of fatal sporadic fulminant necrotizing viral encephalitis and has characteristic imaging findings. Two subtypes are recognized which differ in demographics, virus, and pattern of involvement. They are 1: neonatal herpes encephalit...

Grey matter heterotopia

The grey matter heterotopias are a relatively common group of conditions characterized 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. Grey m...

Central nervous system germinoma

Intracranial germinomas, also known as dysgerminomas or extra-gonadal seminomas, are a type of germ cell tumor and are predominantly seen in pediatric populations. They tend to occur in the midline, either at the pineal region (majority) or along the floor of the third ventricle/suprasellar regi...

Ganglioglioma

Gangliogliomas are uncommon, usually low-grade, CNS tumors. Epilepsy is a common clinical presentation and this tumor has a typical occurrence in the temporal lobes, although they have been described in all parts of the central nervous system. Their appearance on imaging is very variable: from ...

Galeazzi fracture-dislocation

Galeazzi fracture-dislocations consist of a fracture of the distal part of the radius with disruption of the distal radioulnar joint. A Galeazzi-equivalent fracture is a distal radial fracture with a distal ulnar physeal fracture 2. Epidemiology Galeazzi fractures are primarily encountered in ...

Fibromatosis colli

Fibromatosis colli is a rare form of infantile fibromatosis that occurs within the sternocleidomastoid muscle. Epidemiology Fibromatosis colli typically presents a few weeks after birth. There may be a slight male predilection. Clinical presentation Infants present with torticollis. It is un...

Fibroxanthoma of bone

Fibroxanthoma of bone and metaphyseal fibrous defect are terms that have been previously to encompass both non-ossifying fibroma and fibrous cortical defect or synonymous with non-ossifying fibroma 1-4. Non-ossifying fibroma and fibrous cortical defect are histologically the same and the differe...

Hemimegalencephaly

Hemimegalencephaly is a rare congenital disorder of cortical formation with hamartomatous overgrowth of all or part of a cerebral hemisphere. This results from either increased proliferation or decreased apoptosis (or both) of developing neurons 2. Epidemiology Hemimegalencephaly is a cryptoge...

Elbow ossification

Elbow ossification occurs at the six elbow ossification centers in a reproducible order. Being familiar with the order of ossification of the elbow is important in not mistaking an epicondylar fracture for a normal ossification center. Appearance Order The order of appearances of the elbow o...

Edwards syndrome

Edwards syndrome, also known as trisomy 18, along with Down syndrome (trisomy 21) and Patau syndrome (trisomy 13), make up the only three autosomal trisomies to be compatible with extrauterine life in non-mosaic forms, albeit in the case of Edward syndrome only for a week or so. Epidemiology ...

Echogenic fetal bowel

Echogenic fetal bowel is an observation in antenatal ultrasound imaging, in which fetal bowel appears to be brighter than it is supposed to be. It is a soft marker for trisomy 21 and has several other associations. When observed, it needs to be interpreted in the context of other associated abno...

Developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH), or in older texts congenital dislocation of the hip (CDH), denotes aberrant development of the hip joint and results from an abnormal relationship of the femoral head to the acetabulum. Unlike CDH, developmental dysplasia of the hip is not confined to c...

Cystic fibrosis

Cystic fibrosis (CF), also called mucoviscidosis, is an autosomal recessive genetic disease that affects the exocrine function of the lungs, liver, pancreas, small bowel, sweat glands, and the male genital system 11. This is resulting in progressive disability and multisystem failure. This artic...

Cystic hygroma

Cystic hygroma, also known as cystic or nuchal lymphangioma, refers to the congenital macrocystic lymphatic malformations that most commonly occur in the cervicofacial regions, particularly at the posterior cervical triangle in infants. Terminology While these lesions are commonly known as cys...

Croup

Croup, also known as acute laryngotracheobronchitis, is due to viral infection of the upper airway by parainfluenza virus or respiratory syncytial virus (RSV). Although imaging findings are not required for the diagnosis, classic findings of narrowing of the subglottic airway and dilatation of ...

Craniosynostosis

Craniosynostosis (plural: craniosynostoses) refers to the premature closure of the cranial sutures. The skull shape then undergoes characteristic changes depending on which suture(s) close early. Epidemiology There is a 3:1 male predominance with an overall incidence of 1 in 2000-2500. 8% of c...

Corkscrew sign (midgut volvulus)

The corkscrew sign describes the spiral appearance of the distal duodenum and proximal jejunum seen in midgut volvulus 1. In patients with malrotation and volvulus, the distal duodenum and proximal jejunum do not cross the midline and instead pass in an inferior direction. These loops twist on ...

Congenital megaureter

A congenital (primary) megaureter encompasses causes of an enlarged ureter which are intrinsic to the ureter, rather than as a result of a more distal abnormality; e.g. bladder, urethra (see secondary megaureter). It includes: obstructed primary megaureter refluxing primary megaureter althoug...

Congenital facial palsy

A congenital facial palsy is an uncommon cause of neonatal asymmetric crying facies, which are more frequently due to absence or hypoplasia of the depressor anguli oris muscle, often associated with other congenital anomalies. Epidemiology Congenital facial palsy is reported with an incidence...

Congenital diaphragmatic hernia

Congenital diaphragmatic herniation (CDH) accounts for a small proportion of all diaphragmatic herniae. However, it is one of the most common non-cardiac fetal intrathoracic anomalies. Epidemiology Congenital diaphragmatic hernias are seen in 1 of every 2000-4000 live births. 84% are left-side...

Congenital cholesteatoma

Congenital cholesteatomas are identical to epidermoid cysts, differing only in name and location. Pathology They are intraosseous inclusions of the ectoderm and are therefore comprised of keratin debris and cholesterol. Characteristically, they are located at the petrous apex. In contrast, mi...

Congenital lobar overinflation

Congenital lobar overinflation (CLO), previously called congenital lobar emphysema, is a congenital lung abnormality that results in progressive overinflation of one or more lobes of a neonate's lung. On imaging, it classically presents on chest radiographs as a hyperlucent lung segment with o...

Congenital cardiovascular anomalies

Congenital cardiovascular anomalies are relatively common, with an incidence of up to 1% if small muscular ventricular septal defects (VSDs) are included. As a group, there is a much greater frequency in syndromic infants and in those that are stillborn. Epidemiology In a large study in the U...

Congenital pulmonary airway malformation

Congenital pulmonary airway malformations (CPAM) are multicystic masses of segmental lung tissue with abnormal bronchial proliferation. CPAMs are considered part of the spectrum of bronchopulmonary foregut malformations. Terminology Until recently, they were described as congenital cystic aden...

Chiari I malformation

Chiari I malformation is the most common variant of the Chiari malformations and is characterized by a caudal descent of the cerebellar tonsils (and brainstem in its subtype, Chiari 1.5) through the foramen magnum. Symptoms are proportional to the degree of descent. MRI is the imaging modality o...

Cervix sign (pyloric stenosis)

The cervix sign of pyloric stenosis describes the indentation of the pylorus into the fluid-filled antrum, seen in pyloric stenosis on ultrasound examination. See also antral nipple sign (pyloric stenosis) target sign (pyloric stenosis)

Cephalohematoma

Cephalohematomas are traumatic subperiosteal hematomas of the skull that are usually caused by birth injury. They are bound between the periosteum and cranium, and therefore cannot cross sutures. Being bound by a suture line distinguishes them from subgaleal hematoma, which can cross sutures. E...

Capillary hemangioma of the orbit

Capillary hemangiomas of the orbit, also known as strawberry hemangiomas, on account of its coloring, or orbital infantile hemangiomas, are the most common orbital tumors of infancy, and unlike orbital cavernous hemangiomas, they are neoplasms rather than vascular malformations. Clinical presen...

Canavan disease

Canavan disease, also known as spongiform degeneration of white matter (not to be confused with Creutzfeldt-Jakob Disease) or aspartoacylase deficiency, is a leukodystrophy clinically characterized by megalencephaly, severe mental and neurological deficits, and blindness. Epidemiology Canavan...

Elbow ossification (mnemonic)

Mnemonics for elbow ossification include CRITOE and CRITOL. These are essentially the same, apart from the terminal letter which represents the External or Lateral epicondyle. Mnemonics CRITOE C: capitellum R: radial head I: internal epicondyle T: trochlea O: olecranon E: external epicon...

CHARGE syndrome

CHARGE syndrome is a phenotype associated with CHD7 gene mutation originally defined by a constellation of congenital anomalies: C: coloboma H: heart defects A: atresia choanae R: retarded growth and development G: genital hypoplasia E: ear abnormalities and/or deafness According to updat...

Bronchial atresia

Bronchial atresia is a developmental anomaly characterized 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...

Brodie abscess

Brodie abscess is an intraosseous abscess related to a focus of subacute or chronic pyogenic osteomyelitis. Unfortunately, there is no reliable way to radiographically exclude a focus of osteomyelitis. It has a protean radiographic appearance and can occur at any location and in a patient of any...

Brain tumors in infancy

Common brain tumors in infancy (i.e. under one year of age) are quite different from those of brain tumors in adulthood. Most are located in the supratentorial region (~65%) and they carry a poor prognosis. The frequency of these tumors varies according to studies, but the most common brain tum...

Bochdalek hernia

Bochdalek hernias , also known as pleuroperitoneal hernias, (alternative plural: herniae) are the commonest type of congenital diaphragmatic hernia. They occur posteriorly and are due to a defect in the posterior attachment of the diaphragm when there is a failure of pleuroperitoneal membrane cl...

Blount disease

Blount disease refers to a local disturbance of growth of the medial aspect of the proximal tibial metaphysis and/or epiphysis that results in tibia vara. The condition is commonly bilateral. Epidemiology There is no recognized inheritance pattern. Clinical presentation Clinically, the chi...

Banana sign (cerebellum)

The banana sign is one of the many notable fruit inspired signs. This sign is seen on axial imaging through the posterior fossa of fetuses with associated conditions such as Chiari II malformation and/or spina bifida. In Chiari II malformation, the banana sign describes the way the cerebellum...

Bochdalek hernia features (mnemonic)

A helpful mnemonic for remembering the features of a Bochdalek hernia is: 5 Bs Mnemonic B: Bochdalek B: big B: back and lateral, usually on the left side B: baby B: bad (associated with pulmonary hypoplasia) To remember the side in which a Bochdalek hernia more commonly occurs (and to co...

Apple-peel intestinal atresia

Apple-peel intestinal atresia, also known as type IIIb or Christmas tree intestinal atresia, is a rare form of small bowel atresia in which the duodenum or proximal jejunum ends in a blind pouch and the distal small bowel wraps around its vascular supply in a spiral resembling an apple peel. Oft...

Acute appendicitis

Acute appendicitis (plural: appendicitides) is an acute inflammation of the vermiform appendix. It is a very common condition in general radiology practice and is one of the main reasons for abdominal surgery in young patients. CT is the most sensitive modality to detect appendicitis. Terminolo...

Antral nipple sign (pyloric stenosis)

The antral nipple sign refers to redundant pyloric mucosa protruding into the gastric antrum and is seen in hypertrophic pyloric stenosis on ultrasound examination. See also cervix sign (pyloric stenosis) target sign (pyloric stenosis)

Anterior inferior iliac spine avulsion injury

Anterior inferior iliac spine (AIIS) avulsion injuries are one of the six main types of pelvic apophyseal avulsion fractures. Subacute or chronic avulsion injuries can be mistaken for a pseudotumor. Epidemiology As with many pelvic avulsion injuries, they most often occur in adolescents (most...

Aneurysmal bone cyst

Aneurysmal bone cysts (ABC) are benign expansile osteoclastic giant cell-rich bony neoplasms, composed of numerous blood-filled channels and cystic spaces 1. ABC accounts for the 'A' in the popular mnemonic for lucent bone lesions FEGNOMASHIC. Terminology The terms 'giant cell reparative gran...

Dysgenesis of the corpus callosum

Dysgenesis of the corpus callosum may be complete (agenesis) or partial (dysgenesis) and represents an in utero developmental anomaly. It can be divided into: primary agenesis: corpus callosum never forms secondary dysgenesis: corpus callosum forms normally and is subsequently destroyed Epide...

Acute mastoiditis

Acute mastoiditis refers to a suppurative infection of the mastoid air cells. It is the most common complication of acute otitis media. Terminology In acute otitis media, an inflammatory middle ear effusion is present that can freely move into the mastoid air cells. Consequently, some authors ...

Achondroplasia

Achondroplasia is a congenital genetic disorder resulting in rhizomelic dwarfism and is the most common skeletal dysplasia. It has numerous distinctive radiographic features. Epidemiology It occurs due to sporadic mutations in the majority of cases but can be inherited as an autosomal dominan...

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