Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

1,159 results found
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Abdominal hernia

Abdominal herniations may be congenital or acquired and come with varying eponyms. They are distinguished primarily based on location and content. 75-80% of all hernias occur in the inguinal region. Content of the hernia is variable, and may include: small bowel loops mobile colon segments (s...
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Abdominal opacities

An opacity projecting over the abdomen has a broad differential. Possibilities to consider include foreign bodies ingested, e.g. coins, batteries, bones, etc artifacts, e.g. object attached to the cloth of the patient like a safety pin or button iatrogenic, e.g. haemostatic clips, gastric ba...
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Abdominoschisis

Abdominoschisis refers to a split or in the abdominal wall. Some authors use the term synonymously with a gastroschisis. When the defect continues into the thoracic region it is termed a thoraco-abdominoschisis. A large abdominoschisis is considered part of the limb body wall complex 2. See als...
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Abnormal bowel wall attenuation patterns

Abnormal bowel wall attenuation patterns on CT scan can be grouped under five categories: white enhancement gray enhancement water halo sign fat halo sign black attenuation The first three patterns are seen on contrast studies. White enhancement It is defined as uniform enhancement of th...
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Abnormally thickened endometrium: differential diagnosis

Abnormally thickened endometrium on imaging may occur for a number of reasons which may be categorised based on whether or not they are related to pregnancy. Aetiologies may also be classified based on whether the patient is premenopausal or postmenopausal. Differential diagnosis Pregnancy rel...
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Abscess

Abscesses are focal confined collections of suppurative inflammatory material and can be thought of as having three components 1: central core comprised of necrotic inflammatory cells and local tissue peripheral halo of viable neutrophils surrounded by a 'capsule' with dilated blood vessels a...
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Absent septum pellucidum

An absent septum pellucidum may rarely be an isolated finding, or more commonly be seen in association with a variety of conditions. Epidemiology The septum pellucidum is partly or entirely absent in 2 or 3 individuals per 100,000 in the general population.  Pathology An absent septum pelluc...
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Achilles tendon thickening

Achilles tendon thickening can occur for a number of reasons. The achilles tendon has an average AP diameter of 6 mm 1. Thickening of the tendon is when it exceeds 8 mm in AP diameter and can result from: achilles tendinosis/tear post-surgical thickening retrocalcaneal bursitis degeneration...
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Acquired aortic conditions

There are many acquired aortic conditions. These include aortic dissection aortic rupture / transection ascending aortic aneurysm aortitis thoracic aortic injury abdominal aortic aneurysm inflammatory abdominal aortic aneurysm
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Acro-osteolysis

Acro-osteolysis refers to resorption of the distal phalanx. The terminal tuft is most commonly affected but the shaft of the distal phalanx can also be affected in a few conditions. It is associated with a heterogeneous group of pathological entities and, some of which can be remembered by using...
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Acute airspace opacification with lymphadenopathy: differential diagnosis

Acute airspace opacification with lymphadenopathy is a subset of the differential diagnosis for generalised airspace opacification and includes: post obstructive causes (usually chronic, but 'new' changes can occur) primary lung cancer pulmonary metastases lymphoma / leukaemia infection p...
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Acute aortic syndrome

Acute aortic syndrome (AAS) describes the presentation of patients with one of a number of life threatening aortic pathologies that give rise to aortic symptoms. The spectrum of these aortic emergencies include: aortic dissection aortic intramural haematoma penetrating atherosclerotic ulcer ...
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Acute basilar artery occlusion

Acute occlusion of the basilar artery may cause brainstem or thalamic ischaemia or infarction. It is a true neuro-interventional emergency and, if not treated early, brainstem infarction results in rapid deterioration in the level of consciousness and ultimately death. Epidemiology Occlusions ...
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Acute bilateral airspace opacification (differential)

Acute bilateral airspace opacification is a subset of the larger differential diagnosis for airspace opacification. An exhaustive list of all possible causes of acute bilateral airspace opacities is long, but a useful way to consider the huge list is by the material within the airways: ...
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Acute gastritis

Acute gastritis is a broad term for myriad causes of gastric mucosal inflammation.  Epidemiology  Depends on the aetiology (see below).  Clinical presentation asymptomatic epigastric pain/tenderness nausea and vomiting loss of appetite  Pathology  Aetiology infection: H. pylori (most c...
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Acute hepatitis

Acute hepatitis occurs when the liver suffers an injury with a resulting inflammatory reaction. The cause of the injury can occur in multiple different ways, and imaging findings are often non-specific. Ultrasound and MRI may be useful imaging modalities to suggest the diagnosis, but often the d...
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Acute sinusitis

Acute sinusitis is an acute inflammation of the nasal and paranasal sinus mucosa that last less than four weeks and can occur in any of the paranasal sinuses. Clinical presentation Fever, headache, postnasal discharge of thick sputum, nasal congestion and abnormal smell. Pathology Aetiology ...
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Acute unilateral airspace opacification (differential)

Acute unilateral airspace opacification is a subset of the differential diagnosis for airspace opacification.  The exhaustive list of all possible causes would be huge, but a useful framework includes : pus, i.e. infection bacterial pneumonia fungal pneumonia viral pneumoni...
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Acute vs chronic ischaemic stroke

Differentiating between acute and chronic infarction on a CT brain is an important skill for many health professionals particularly in the emergency setting: pathology acute: cytotoxic oedema chronic: encephalomalacia; Wallerian degeneration hypoattenuation acute: more dense than CSF chron...
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Adenosis of the breast

Adenosis of the breast is a benign lobulocentric proliferative process in which lobules are enlarged and increased in number in addition to an increased number of glands within each lobule. Pathologically subclassified into three main subtypes which include: sclerosing adenosis of the breast ...
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Adrenal calcification

Adrenal calcification is not a rare finding in healthy asymptomatic people, and is usually the result of previous haemorrhage, or tuberculosis. Addison's disease patients only occasionally have calcification.  Pathology Aetiology Haemorrhage sepsis: Waterhouse-Friderichsen syndrome blunt ab...
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Adrenal haemorrhage

Adrenal haemorrhage can result from a variety of causes (traumatic as well as non-traumatic). When unilateral, it is often clinically silent. In contrast, bilateral adrenal haemorrhage can lead to catastrophic adrenal insufficiency. Clinical presentation The large majority of patients with uni...
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Adrenal lesions

Adrenal lesions cover a broad spectrum from benign to neoplastic entities. Due to increased use of cross sectional imaging they are frequently detected as incidental lesions. Radiology plays a significant role in differentiation. Cross sectional imaging is the mainstay of imaging for identifyin...
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Adult cystic renal disease

Adult cystic renal disease comprises multiple distinct hereditary and non-hereditary disease processes.  Pathology Aetiology Hereditary adult polycystic kidney disease (APCKD), a.k.a. autosomal dominant polycystic kidney disease (ADPCKD) medullary cystic kidney disease von Hippel-Lindau di...
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AFP elevation

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 tumor since it may occur in a setting of diffuse live...
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AIDS defining illness

AIDS defining illnesses are conditions that in the setting of a HIV infection confirm the diagnosis of AIDS, and do not commonly occur in immunocompetent individuals 2. According to the CDC surveillance case definition 1, they are: Infectious bacterial infections: multiple or recurrent candid...
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Air crescent sign

An air crescent sign describes the crescent of air that can be seen in invasive aspergillosis, semi-invasive aspergillosis or other processes that cause pulmonary necrosis. It usually heralds recovery and is the result of increased granulocyte activity. In angioinvasive fungal infection, the no...
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Air space opacification

Air space opacification is a descriptive term that refers to filling of the pulmonary tree with material that attenuates x-rays more than the surrounding lung parenchyma.  It is one of the many patterns of lung opacification and is equivalent to the pathological diagnosis of pulmonary consolidat...
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Air space opacities

The differential for air space opacities is extensive, and needs to be interpreted in context of chronicity (previous imaging) and clinical context. It is therefore useful to divide airspace opacities as follows: acute airspace opacities with lymph node enlargement acute airspace opacities: un...
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Airway foreign bodies in children

Airway foreign bodies in children are potentially fatal and proper recognition is important because delayed diagnosis is common.  Epidemiology Children under the age of four years are at increased risk of foreign body (FB) aspiration with a slight male predominance 1.  Clinical presentation ...
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Altered breast density between two mammograms

Mammographic screening detects early breast cancers and thereby reduces potential mortality. However, its sensitivity is inversely related to breast density 1.  Altered density between two mammograms can arise in a number of situations: Affecting both breasts: interval commencement/cessation ...
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Alternating radiolucent and radiodense metaphyseal lines

Alternating radiolucent and radiodense metaphyseal lines can be seen with a number of conditions and the differential diagnosis is wide: growth arrest lines bisphosphonate therapy rickets: especially those on prolonged treatment, e.g. vitamin D dependent rickets osteopetrosis chemotherapy ...
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Amaurosis fugax

Amaurosis fugax is the transient mono-ocular loss of vision, normally lasting a few seconds to a few minutes, and is secondary to vascular ischaemia/insufficiency. Usually the cause is ascribed to occlusion of the central retinal artery there are a wide number of local and central causes. 
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Amorphous calcification within breast

Amorphous or indistinct calcifications are a morphological descriptive term for breast calcification and are defined as having small, hazy, faint calcifications with no clearly defined shape or form.  Radiographic features 80-200 micrometer in diameter small, hazy calcification often magnifi...
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Ampullary tumour

The term ampullary tumour generally refers to either benign or malignant neoplasms that arise from the glandular epithelium of the ampulla of Vater, including 1: ampullary adenoma (adenoma of ampulla of Vater) ampullary carcinoma (carcinoma of ampulla of Vater) According to some authors, ampu...
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Amputation

The term amputation refers to the disconnection of all or part of a limb from the body. Specifically amputation it is defined as removal of the structure through a bone. This is in contrast to disarticulation, which is removal of the structure through a joint. Terminology When due to trauma, t...
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Angiosarcoma of bone

Angiosarcoma of bone is a malignant vascular tumour of bone. These are rare and account for less than 1% of malignant bone tumours. The majority of these tumours arising in bone are primary; however, a tiny percentage is either radiation-induced or associated with bone infarction Epidemiology ...
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Ankle tear drop sign

Ankle tear drop sign is one of the radiological signs of an ankle joint effusion. It represents the presence of fluid in the inferior part of anterior compartment of ankle. Pathology Aetiology trauma gout rheumatoid arthritis synovitis infectious arthritis Radiographic appearance Plain ...
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Anoxic brain injury

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...
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Antenatal features of Down syndrome

Antenatal screening of Down syndrome (and other less common aneuploidies) should be available as a routine component of antenatal care. It allows families to either adjust to the idea of having a child with the condition, or to consider termination of pregnancy. For a general description of Dow...
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Anterior hip pain

Causes of anterior hip pain include: osteoarthritis synovitis including pigmented villonodular synovitis (PVNS) synovial osteochondromatosis inflammatory arthropathy (e.g. rheumatoid arthritis) iliopsoas bursitis ganglion cyst synovial cyst muscle tear malignancy inguinal adenopathy ...
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Anterior inferior cerebellar artery (AICA) infarct

Anterior inferior cerebellar artery (AICA) territory infarcts are much less common than posterior inferior cerebellar artery (PICA) infarcts. Epidemiology AICA territory infarcts are rare, comprising ~1% of ischaemic cerebellar strokes 2.  Clinical presentation AICA stroke syndrome presents ...
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Anterior knee pain

Anterior knee pain is common with a variety of causes including: patella fracture osteoarthritis inflammatory and depositional arthritis bursitis around the knee patellofemoral maltracking excessive lateral pressure syndrome (ELPS) patellar cartilage defect patellofemoral chondromalacia ...
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Anterior superior iliac spine avulsion injury

Anterior superior iliac spine (ASIS) avulsion injuries typically occur in athletes during forceful muscular contraction. ASIS is the site of attachment for sartorius and tensor fascia lata muscles.  Pathology ASIS avulsion, like other pelvic avulsion injuries, is a stable fracture. Treatment ...
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Anterior vertebral body beaking

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. Middle third Morquio syndrome 1 (middle for Morquio) Lower third Hurler syndrome 2 achondroplasia 3 pseudoachondroplasia 4 cretinism 5 Down ...
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Aortic nipple

An aortic nipple is seen in about 10% of PA chest x-rays on the lateral surface of the aortic arch/aortic knob. It represents the left superior intercostal vein. When prominent, superior vena cava obstruction should be considered (the left superior intercostal vein might be a collateral pathway).
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Aortopulmonary window

The aortopulmonary (aortic-pulmonary or AP) window is a radiological mediastinal space seen on frontal chest x-rays. Terminology The term "aortopulmonary window" can also refer to a rare form of congenital heart disease, where there is an opening between the aorta and the pulmonary t...
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Aphthous ulceration

Aphthous ulcers are deep mucosal ulcers of the gastrointestinal mucosa. Pathology Aetiology infective inflammatory conditions Yersinia enterocolitis amoebic enterocolitis cytomegalovirus enterocolitis noninfective inflammatory conditions Crohn disease idiopathic granulomatous gastritis ...
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Apical pleural cap

Apical pleural cap refers to a curved density at the lung apex seen on chest radiograph. Epidemiology The frequency of apical pleural thickening increases with age 3. Pathology It arises from a number of causes: pleural thickening/scarring idiopathic: often a chronic ischaemic aetiology is...
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Architectural distortion in mammography

Architectural distortion is a mammographic descriptive term in breast imaging. It may be visualised as tethering or indentation of breast tissue.  Pathology Architectural distortion per se is not a mass. It is often due to a desmoplastic reaction in which there is focal disruption of the norma...
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Areae gastricae

Areae gastricae are a normal finding on double contrast images of the stomach. Radiographic features fine reticular network of barium-coated grooves between 1-5 mm islands/areas of gastric mucosa may be seen in ~70-80% of patients if there is adequate high-density barium coating of the stomac...
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Arteriovenous malformations

Arteriovenous malformations (AVMs) are characterised by an abnormal leash of vessels allowing for arteriovenous shunting. They can occur anywhere in the body but have a predilection towards the head and neck.  There is a direct arteriovenous communication with no intervening capillary bed. They ...
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Artery of Percheron territory infarct

Artery of Percheron territory infarct is rare, on account of the relative rarity of the artery of Percheron, and presents with a variety of signs and symptoms collectively termed the paramedian thalamic syndrome. It is a type of posterior circulation infarction. On imaging, it is classically ch...
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Arthrogryposis

Arthrogryposis (multiplex congenita) is a clinical or imaging descriptor that denotes congenital non-progressive joint contractures involving two or more body regions.  Epidemiology It is thought to occur in approximately 1:3000-10,000 live births 6,8. Pathology It can result from a number o...
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Asbestos related diseases

Asbestos related disease, in particular affecting the lung, comprise of a broad spectrum of entities related to the inhalational exposure to asbestos fibres. They can be divided into benign and malignant changes 1-3. Benign pleural and parenchymal lung disease asbestos related benign pleural d...
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Ascending aorta dilatation

Dilatation of the ascending aorta is a common finding in the elderly but unusual in younger patients. Pathology In adults, an ascending aortic diameter greater than 4 cm is considered to indicate dilatation 4. Aneurysmal dilatation is considered when the ascending aortic diameter reaches or ex...
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Aseptic loosening of hip joint replacements

Aseptic loosening is considered relatively common complication of hip joint replacements. It is usually considered a long-term complication and is often considered as the most common complication 3. Pathology Aseptic loosening can occur as a result of inadequate initial fixation, mechanical lo...
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Aspiration pneumonia

Aspiration pneumonia is caused by a direct chemical insult due to the entry of a foreign substance, solid or liquid, into the respiratory tract. Clinical presentation Aspiration may be clinically silent, or it may present with dyspnoea, cough or fever. The clinical and radiographic features de...
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Asplenia syndrome

Asplenia syndrome (also known as right isomerism or Ivemark syndrome) is a type of heterotaxy syndrome. Epidemiology There is an increased male predilection. Asplenia syndrome is usually diagnosed in neonates.4 Clinical manifestation In contrast to polysplenia syndrome, most patients die bef...
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Asymmetrical density in mammography

Asymmetrical mammographic density is a mammographic morphological descriptor. It is given when there is increased density in one of the breasts, on either one or both standard mammographic views but without evidence of a discrete mass. An asymmetrical density can be further characterised as: ma...
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Asymmetry in breast size

Asymmetry in breast size can arise from a number of factors. Pathology Breasts are rarely absolutely the same size or volume. Normal variation is common. Most females have slight discrepancies in breast size. Asymmetric progressive breast enlargement is unusual but known. The role of the breas...
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Athletic pubalgia

Athletic pubalgia refers to pain around the pubic symphysis and can have different causes, including what has become known as sports hernia or sportman's hernia and osteitis pubis. Athletic pubalgia is a clinical syndrome of chronic lower pelvic and groin pain, usually encountered in athletes. ...
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Atlantodental interval

The atlantodental interval (ADI), as the name suggests, is the horizontal distance between the anterior arch of the atlas and the dens of the axis, used in the diagnosis of atlanto-occipital dissociation injuries and injuries of the atlas and axis. It is the distance (in mm) between the posteri...
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Atresia

Atresia refers to a situation where there is underdevelopment of a structure with very rudimentary remnant tissues. This contrasts with an agenesis meaning there is no development of the structure as all. The term atresia is often used with hollow structures such as a bronchus or intestine.  Fo...
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Autoimmune thyroiditis

Autoimmune thyroiditises (AIT) refers to a group of conditions where there is inflammation involving the thyroid gland related to thyroid antibodies. Epidemiology They are most common thyroid disease group in the paediatric population 5. Pathology Entities that fall under this category inclu...
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Avulsion fractures of the knee

Avulsion fractures of the knee are numerous due to the many ligaments and tendons inserting around this joint. They include 1: anterior cruciate ligament avulsion fracture posterior cruciate ligament avulsion fracture avulsion of the medial collateral ligament origin of MCL avulsion fracture...
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Avulsion injuries

Avulsion injuries, where a portion of cortical bone is ripped from the rest of the bone by the attached tendon, are common among those who participate in sports, and there are numerous sites at which these occur. Being familiar with them is important as chronic injuries can appear aggressive. S...
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Barium peritonitis

Barium peritonitis is a rare complication of gastrointestinal fluoroscopy, and occurs when there is gastrointestinal tract perforation and spillage of barium into the peritoneal cavity.  Pathology Barium in the peritoneal cavity is treated as a foreign body with resultant immune response that ...
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Bartholin gland tumours

Bartholin gland tumours include: squamous cell carcinoma of the Bartholin gland: tends to be the most common histological subtype adenocarcinoma of the Bartholin gland adenoid cystic carcinoma of the Bartholin gland
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Barton fracture

Barton fractures are fractures of the distal radius. It is also sometimes termed the dorsal type Barton fracture to distinguish it from the volar type or reverse Barton fracture. Barton fractures extend through the dorsal aspect to the articular surface but not to the volar aspect. Therefore, i...
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Basal ganglia calcification

Basal ganglia calcification is common and is seen in approximately 1% of all CT scans of the brain, depending on the demographics of the scanned population. It is seen more frequently in older patients and is considered a normal incidental and idiopathic finding in an elderly patient but should ...
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Basal ganglia T1 hyperintensity

There are many causes of basal ganglia T1 hyperintensity, but the majority relate to deposition of T1-intense elements within the basal ganglia such as: calcium idiopathic calcification calcium and phosphate abnormalities hepatic failure acquired non-wilsonian hepatocerebral degeneration W...
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Basal ganglia T2 hyperintensity

The causes of basal ganglia T2 hyperintensity can be remembered using the mnemonic LINT: lymphoma ischaemia hypoxia venous infarction (internal cerebral vein thrombosis) neurodegenerative / metabolic Wilson disease Huntington disease: especially caudate heads methylmalonic acidaemia mit...
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Basal ganglia T2 hypointensity

Basal ganglia T2 hypointensities can be caused by any of the following and is commonly remembered using the mnemonic ChOMP. childhood hypoxia old age multiple sclerosis Parkinson disease: more in globus pallidus Parkinson-plus syndrome: more in putamen deoxyhemoglobin of hemorrhage haemos...
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Basilar invagination

Basilar invagination, also called basilar impression, is a congenital or acquired craniocervical junction abnormality where the tip of the odontoid process projects above the foramen magnum.  Terminology The terms basilar invagination and basilar impression are often used interchangeably becau...
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Basion-axial interval

The basion-axial interval (BAI), as the name suggests, is the horizontal distance between the basion and the posterior cortex of the axis, used in the diagnosis of atlanto-occipital dissociation injuries. It is the distance (in mm) between the basion and the superior extension of the posterior ...
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Basion-dens interval

The basion-dens interval (BDI), as the name suggests, is the distance between the basion and the tip of the dens, used in the diagnosis of atlanto-occipital dissociation injuries. It is the distance from the most inferior portion of the basion to the closest point of the superior aspect of the ...
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Bat wing pulmonary opacities

Bat's wing or butterfly pulmonary opacities refer to a pattern of bilateral perihilar shadowing. It is classically described on a frontal chest radiograph but can also refer to appearances on chest CT 3-4. Differential diagnosis Bat's wing pulmonary opacities can be caused by: pulmonary oedem...
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Benign and malignant characteristics of breast lesions at ultrasound

Benign and malignant characteristics of breast lesions at ultrasound allow the classification as either malignant, intermediate or benign based on work published by Stavros et al in 1995. Radiographic features Ultrasound Malignant characteristics (with positive predictive values) sonographic...
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Benign liver tumours (paediatric)

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 haemangioendothelioma mesenchymal hamartoma of t...
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Benign lytic bone lesions

Benign lytic bone lesions encompass a wide variety of entities.  A useful starting point is the FEGNOMASHIC mnemonic. This article is a stub, which means it needs more content. You can contribute to Radiopaedia too. Just register and click edit... every little bit helps. See also malignant l...
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Benign metastasising tumours

There are a number of benign metastasising tumours: benign metastasising meningioma 1,2 benign metastasising leiomyoma 3 primary adenoma of thyroid 4 giant cell tumour of bone 5
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Benign minor salivary gland pathology

Benign minor salivary gland pathology is a broad term that encompasses a number of relatively uncommon pathologies that affect the minor salivary glands of the head and neck: salivary retention cysts benign neoplasms pleomorphic adenoma
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Benign oesophageal lesions

Benign oesophageal lesions are less symptomatic than malignant oesophageal lesions, making up for only 1% of clinically apparent oesophageal lesions. Pathology oesophageal leiomyoma (>50%) may calcify oesophageal fibrovascular polyp (~12.5%) may contain fat oesophageal duplication cyst ...
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Benign tumours and tumour-like lesions of the gallbladder

The gallbladder and extrahepatic bile ducts play host to a surprisingly large number of benign tumours and tumour-like lesions which may be visible on imaging. In the gallbladder most of them are detected incidentally, whereas in the bile ducts they are usually found in symptomatic patients (obs...
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Bent bone dysplasias (differential)

Bent bone dysplasias are a class of dysplasia included in a 2010 classification of genetic skeletal disorders 1. campomelic dysplasia Stuve-Weidemann dysplasia kyphomelic dysplasias, a diverse class, including congenital bowing of the long bones cartilage-hair hypoplasia (CHH; metaphyseal d...
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Bentall procedure

Bentall procedure is performed for the repair of ascending aortic root lesions. Typically the native aortic root and aortic valve are replaced with a composite graft that comprises of both ascending aortic and aortic valve grafts, into which the coronary arteries are anastomosed. History and et...
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Beta-hCG

Beta-hCG is a hormone found in the mother's blood serum that can be used to help interpret ultrasound findings. Beta-hCG levels may be used in three ways: qualitatively, for presence/absence of fetal tissue more often determined with a urine test than with a serum test includes or excludes a...
Article

Bicaudate index

The bicaudate index is the ratio of width of two lateral ventricles at the level of the head of the caudate nucleus to distance between outer tables of skull at the same level. It can be a useful marker of ventricular volume and in the diagnosis of hydrocephalus. 
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Bilateral adrenal enlargement

The differential for bilaterally enlarged adrenal glands is relatively limited: adrenal hyperplasia micronodular adrenal hyperplasia macronodular adrenal hyperplasia adrenocorticotropin (ACTH)-independent macronodular adrenocortical hyperplasia (AIMAH) 2 adrenal metastases adrenal haemorrh...
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Bilateral megalencephaly

Bilateral megalencephaly refers to megalencephaly affecting both cerebral hemispheres. Pathology Associations achondroplasia acromegaly Alexander disease Canavan disease mucopolysaccharidoses neurofibromatosis type 1 (NF1) Proteus syndrome Tay-Sachs disease tuberous sclerosis (TS) va...
Article

Bilateral middle cerebellar peduncle lesions

Involvement of both middle cerebellar peduncles is uncommon, but has a relatively long differential, including 1: neurodegenerative diseases multiple systemic atrophy (MSA) olivopontocerebellar atrophy Shy-Drager syndrome spinocerebellar atrophy metabolic diseases  adrenoleukodystrophy ...
Article

Bilateral renal enlargement

Bilateral renal enlargement can arise from a number of causes which include renal involvement with lymphoma adult dominant polycystic kidneys (ADPKD) von-Hippel-Lindau disease nephroblastomatosis tuberous sclerosis bilateral renal cell carcinoma

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