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.

13,581 results found
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Arthogram (anesthetic)

An arthrogram injection is a procedure in which a solution is administered into a joint under imaging guidance.  These procedures are more accurately named direct arthrogram injections, although they are routinely known as arthrograms.  Fluoroscopy, ultrasound, and CT can be used for image guida...
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Scleroderma (gastrointestinal manifestations)

Gastrointestinal manifestations of scleroderma can occur in up to 90% of patients with scleroderma 2 with the commonest site of gastrointestinal involvement being the esophagus. After skin changes and Raynaud phenomenon, gastrointestinal changes are 3rd most common manifestation of scleroderma. ...
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Hand series (pediatric)

The hand series for pediatrics often consist of a posteroanterior and lateral view only in order to minimize radiation dose to the patient. This may vary depending on the department.  Indications trauma with suspected fracture suspected dislocation foreign body detection Projections Standa...
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Arthrogram

An arthrogram (or arthrography) is a commonly used term in musculoskeletal radiology, which can refer to both an injection into a joint, and cross-sectional imaging after a joint is injected. Indications Arthrograms are performed for a variety of indications including:  labral tear after shou...
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Arthrogram (MRI)

An MR arthrogram is an MRI performed after a joint is injected with a solution containing gadolinium. Sometimes abbreviated to MRA, which can be confused with MR angiography.  MRI can also be performed after an injection is not directly administered into the joint, via an indirect arthrogram.  A...
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Vertebral levels (anatomical landmarks)

Many vertebral levels are associated with key anatomical landmarks. Below is a summary of vertebral levels and associated internal or surface anatomy. Please note that some texts differ slightly on certain levels and levels may be altered by patient positioning (supine versus erect) and patient ...
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Cerebellopontine angle mass (mnemonic)

Mnemonics for the common cerebellopontine angle masses include: AMEN or MEAN SAME ANGLES Mnemonics AMEN/MEAN A: acoustic neuroma (a.k.a. vestibular schwannoma) (~80%) M: meningioma (~10%) E: ependymoma (~5%) N: neuroepithelial cyst (arachnoid/epidermoid) (~5%) SAME S: schwannoma  ves...
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Epiploic appendagitis

Epiploic appendagitis is a rare self limiting inflammatory/ischemic process involving an appendix epiploica of the colon and may either be primary or secondary to adjacent pathology. This article pertains to primary (spontaneous) epiploic appendagitis. The term along with omental infarction is g...
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Arthrogram (CT)

A CT arthrogram is a CT performed after a joint is injected with a solution containing iodinated contrast.  They are not commonly abbreviated to CTA, which will be confused with CT angiography. An arthrogram also refers to the procedure of injecting a joint. Indications shoulder - instability/...
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Upper limb radiography (pediatric)

Upper limb radiography involves plain film imaging of the shoulder, humerus, ulna, radius, metacarpals and carpal bones in pediatric patients. Depending on the patients' age, the difficulty of the examination will vary, often requiring a specialist trained radiographer familiar with a variety of...
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Pediatric hand (PA view)

The posteroanterior hand view for pediatrics is part of a two view series metacarpals, phalanges, carpal bones and distal radioulnar joint.  Patient position patient is seated alongside the table the affected arm if possible is flexed at 90° so the arm and hand can rest on the table the affe...
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Crossover sign (femoroacetabular Impingement)

The crossover sign, also known as the 'figure of 8' sign, is a plain film sign that indicates acetabular retroversion 2. Acetabular retroversion is a predisposing factor for pincer-type femoroacetabular impingement and is thought to promote hip osteoarthritis 3.  Radiographic features Plain ra...
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Femoroacetabular impingement

Femoroacetabular impingement (FAI) refers to a clinical syndrome of painful, limited hip motion resulting from certain types of underlying morphological abnormalities in the femoral head/neck region and/or surrounding acetabulum. FAI can lead to early degenerative disease. Epidemiology Pincer ...
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Scleroderma (musculoskeletal manifestations)

Musculoskeletal manifestations of scleroderma are common and variable. For a general discussion of scleroderma, please refer to the parent article: scleroderma. Radiographic features Plain radiograph Imaging findings demonstrate bone and soft tissue changes 2-4. The hands are the most common...
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Low-lying tonsils

Low-lying tonsils, sometimes also called benign tonsillar ectopia, is a subtype of cerebellar tonsillar ectopia denoting asymptomatic and only slight downward descent of the cerebellar tonsils through the foramen magnum and is distinct from Chiari I malformations. Typically a descent of less tha...
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Normal chest imaging examples

This article lists examples of normal imaging of the chest and surrounding structures, divided by modality. Plain radiographs Adult examples chest radiograph PA adult male example 1 example 2: with inverted windows example 3 PA adult female example 1 example 2 example 3: with labels ...
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Critical shoulder angle

Critical shoulder angle (CSA) is a parameter, that in some studies 1, correlates with rotator cuff tear (RCT) or glenohumeral osteoarthritis (OA). Some studies 5,6 have shown CSA not associated with RCT.  The CSA measures acromial cover and the inclination of the glenoid, integrating both anato...
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Cerebellar agenesis

Cerebellar agenesis is a rare congenital abnormality which can result from failure to develop normal cerebellar tissue or destruction of normally developed tissue. For a more general overview of cerebellar malformations, please refer to the article on classification systems for malformations of...
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Peutz-Jeghers syndrome

Peutz-Jeghers syndrome is one of the polyposis syndromes. It has an autosomal dominant inheritance and is characterized by: multiple hamartomatous polyps, most commonly involving the small intestine (predominantly the ileum), but also colon and stomach; mouth and esophagus are spared mucocutan...
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Ingested bones

Ingested bones that become lodged in the throat or gastrointestinal tract are a common presentation to the emergency department. Recognition is important because these cases can be potentially fatal.  Clinical presentation Fish bones are more commonly ingested than chicken or pork bones. Patie...
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Anterior resection syndrome

Anterior resection syndrome refers to wide spectrum of symptoms which develop post-sphincter preserving rectal resection for rectal cancer. Pelvic radiotherapy is a known risk factor to develop anterior resection syndrome. Clinical presentation Symptoms include but are not limited to: increa...
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Cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS)

Cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS) is a rare neurodegenerative balance disorder characterized by cerebellar ataxia, sensory neuronopathy (ganglionopathy), and bilateral vestibular hypofunction. Epidemiology The epidemiology is yet to be defined, but CA...
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Tuberculosis (intracranial manifestations)

Tuberculosis of the central nervous system can result from either haematogenous spread from distant systemic infection (e.g. pulmonary tuberculosis) or direct extension from local infection (e.g. tuberculous otomastoiditis). Intracranial manifestations of tuberculosis are protean and can affect...
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Cerebral arteriovenous malformation

Cerebral arteriovenous malformations (CAVMs), also known as classic brain AVMs, are a common form of cerebral vascular malformation and are composed of a nidus of vessels through which arteriovenous shunting occurs. Terminology This article corresponds to the classic form of arteriovenous malf...
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Pulmonary hypertension (differential)

Pulmonary hypertension has many causes, and these can be divided in many ways. A simple and systematic approach is to proceed along the cardiopulmonary pulmonary circulation, as causes are found at each site (for a more official classification system see 2003 third world symposium on pulmonary a...
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Pulmonary tumoral thrombotic microangiopathy

Pulmonary tumor thrombotic microangiopathy (PTTM) occurs when there are tumor cell microemboli ("non-occlusive" microscopic tumor emboli2) with "occlusive" fibrointimal remodelling in small pulmonary arteries, veins and lymphatics. It is considered one of the processes of microsopic pulmonary tu...
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Chronic pulmonary embolism

Chronic pulmonary emboli are mainly a consequence of incomplete resolution of pulmonary thromboembolism. Radiographic features CTPA vascular CT signs include direct pulmonary artery signs complete obstruction partial obstruction eccentric thrombus calcified thrombus - calcific pulmonary ...
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High division of brachial artery

The high division of brachial artery is a high up bifurcation into ulnar and radial arteries in the arm. It's an anatomical variant of the arterial branching pattern of the upper limb. Description  The brachial artery normally divides into it's terminal branches at the level of the neck of th...
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Lateral intercostal artery perforator (LICAP) reconstruction

Lateral intercostal artery perforator (LICAP) flap is a technique performed in breast reconstruction. It is considered suitable for some patients who have breast cancer in the outer part of the breast. It aims to replace lost breast tissue, fat and occasionally skin that is removed at the time o...
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Femoral ring

The femoral ring is the superior opening of the femoral canal. Its boundaries are: medial: lacunar ligament anterior: medial part of the inguinal ligament lateral: femoral vein within the intermediate compartment of the femoral sheath posterior: pectineal ligament overlying the pectineus mus...
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Femoral canal

The femoral canal is the medial compartment of the femoral sheath, an inverted cone-shaped fascial space medial to the common femoral vein within the upper femoral triangle. It is only 1-2 cm long and opens superiorly as the femoral ring. It serves two purposes: allows the femoral vein to expan...
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Trapdoor fracture

A trapdoor fracture is a fracture of the orbital floor where the inferiorly displaced blowout fracture recoils back to its original position and potentially entraps contents of the orbit. It is seen in children and young adults due to the elasticity of the orbital floor. These fractures may be s...
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Astroblastoma

Astroblastomas are rare glial tumors usually found in the cerebral hemispheres of young adults and children.  Epidemiology They occur at all ages range from early childhood to 6th decade but are most commonly seen in children, adolescents, and young adults with a mean age between 10-30 years 2...
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Posterolateral corner injury of the knee

Posterolateral corner injury of the knee can occur in isolation or with other internal derangements of the knee, particularly cruciate ligament injuries. The importance of injuries to the posterolateral ligamentous complex lies in the possible long-term joint instability and cruciate graft failu...
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Trigeminal nerve

The trigeminal nerve is the fifth cranial nerve and its primary role is relaying sensory information from the face and head, although it does provide motor control to the muscles of mastication. It is both large and complicated and has multiple brainstem nuclei (sensory and motor) as well as man...
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Bland-Altman analysis

Bland-Altman analysis is a method for comparing two methods of measurement of a continuous variable by plotting them in a specific way (a Bland-Atman plot). Outside of medicine a such a plot is often referred to as a Tukey mean difference plot. Continuous variables which could technically be con...
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Hepatoduodenal ligament

The hepatoduodenal ligament is a peritoneal ligament of lesser omentum containing the portal triad. 1 Gross anatomy The hepatoduodenal ligament is a thickening of the right edge of the lesser omentum and forms the anterior margin of the epiploic foramen. It extends from the porta hepatis to th...
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Generalized increased bone density (mnemonic)

A handy mnemonic for causes of generalized increased bone density / osteosclerosis: Regular Sex Makes Occasional Perversions Much More Fun, Happening and Lovely Mnemonic R: renal osteodystrophy S: sickle cell disease M: metastasis (osteoblastic/sclerotic) O: osteopetrosis  P: pyknodysosto...
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Paraumbilical hernia

Paraumbilical hernias are a type of midline ventral abdominal hernia. Pathology Paraumbilical hernias occur near the umbilicus when abdominal contents protrude through a defect in the linea alba and can be quite large. They are usually related to rectus abdominis muscle divarication.  Differe...
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Cardiothoracic ratio

The cardiothoracic ratio (CTR) aids in the detection of enlargement of the cardiac silhouette, which is most commonly from cardiomegaly but can be due to other processes such as a pericardial effusion.  Terminology Some report cardiothoracic ratio as a percentage, however this is incorrect, as...
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Differential diagnosis for a small cardiothoracic ratio

A small cardiothoracic ratio (CTR) is defined as <42%/0.42 when assessed on a PA chest radiograph, and is often called small heart syndrome. A pathologically-small heart is also known as microcardia.It can be due to/associated with a number of entities: adrenal insufficiency, e.g. Addison disea...
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Kappa

Kappa is a nonparametric test that can be used to measure interobserver agreement on imaging studies. Cohen's kappa compares two observers, or in the case of machine learning can be used to compare a specific algorithm's output versus labels. Fleiss' kappa assesses interobserver agreement betwee...
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Subcoracoid bursa

The subcoracoid bursa is located anterior to subscapularis and beneath the coracoid process and extends caudal to the conjoined tendons of coracobrachialis and short head of biceps brachii. Fluid in the subcoracoid bursa does not normally communicate with the glenohumeral joint but may communica...
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Acute cholangitis

Acute cholangitis, or ascending cholangitis, is a form of cholangitis and refers to the acute bacterial infection of the biliary tree. It is a condition with high mortality that necessitates emergent biliary decompression.  Clinical presentation The classical presentation is the Charcot triad ...
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Chest radiograph

The chest radiograph (also known as the chest x-ray or CXR) is anecdotally thought to be the most frequently-performed radiological investigation globally although no published data is known to corroborate this. UK government statistical data from the NHS in England and Wales shows that the ches...
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HRCT chest

High-resolution CT (HRCT) of the chest, also referred to as HRCT chest or HRCT of the lungs, refers to a CT technique in which thin-slice chest images are obtained and post-processed in a high-spatial-frequency reconstruction algorithm. This technique obtains images with exquisite lung detail, w...
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High-resolution CT

High-resolution CT (HRCT) is a scanning protocol in which thin sections (usually 0.625 to 1.25 mm) are acquired and reconstructed using a sharp algorithm (e.g. bone algorithm). It has been classically used for: lung imaging: HRCT chest  temporal bone imaging
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Pulmonary acinus

Pulmonary acinus is commonly defined as the portion of lung distal to a terminal bronchiole and supplied by a first-order respiratory bronchiole or bronchioles 1.  Each secondary pulmonary lobule usually contains 3-12 acini, and adjacent acini are separated by incomplete intralobular septa. See...
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Secondary pulmonary lobule

The secondary pulmonary lobule, also known as the pulmonary lobule, is considered the functional unit of the lung, and is key to HRCT terminology. Terminology The terminology used to describe the fundamental gas-exchange units of the lung can be confusing. The inconsistent descriptions in part...
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Interlobular septa

The interlobular septa (singular: interlobular septum) are located between the secondary pulmonary lobules and are continuous with both the subpleural interstitium (peripheral connective tissue) and the peribronchovascular interstitium (axial connective tissue) as well as the more delicate intra...
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Pseudogestational sac

A pseudogestational sac, also known as a pseudosac or intra-cavitary fluid, is the concept that a small amount of intrauterine fluid in the setting of a positive pregnancy test and abdominal pain could be erroneously interpreted as a true gestational sac in ectopic pregnancy. The sign was origi...
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Porta hepatis

The porta hepatis is a deep fissure in the inferior surface of the liver through which all the neurovascular structures (except hepatic veins) and hepatic ducts enter or leave the liver 1. It runs in the hepatoduodenal ligament and contains: right and left hepatic ducts right and left branches...
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Increased bone age

A generalized acceleration in bone maturation can result from a number of etiological factors. They include: endocrine disorders idiopathic isosexual precocious puberty hypothalamic or parathalamic lesion with sexual precocity: e.g. craniopharyngioma astrocytoma hypothalamic hamartoma hyp...
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Inferior gemellus muscle

The gemellus inferior and superior are a pair of triangular muscles associated with the upper and lower margins of the obturator internus tendon. Summary origin: upper aspect of ischial tuberosity insertion: along length of inferior surface of the obturator internus tendon and into the media...
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Triceps coxae

The triceps coxae is the tricipital (three headed) collection of 3 muscles in the posterior hip which act together on the hip, primarily to laterally rotate the extended thigh. It comprises (in order from superior to inferior) the superior gemellus, obturator internus and inferior gemellus muscl...
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Sheehan syndrome

Sheehan syndrome is a rare cause of pituitary apoplexy and hypopituitarism. It only occurs in postpartum females who experience large volume hemorrhage and hypovolemic shock, either during delivery or afterward with resultant necrosis of anterior pituitary cells 4. Epidemiology Advances in obs...
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COVID-19

COVID-19 is a zoonotic illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus was previously known as 2019 novel coronavirus. The first cases were seen in the city of Wuhan, China in December 2019, and have been linked to the Huanan Seafood Wholesale Market...
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Crazy paving

Crazy paving refers to the appearance of ground-glass opacity with superimposed interlobular septal thickening and intralobular septal thickening, seen on chest HRCT. It is a non-specific finding that can be seen in a number of conditions.  Pathology Etiology Common causes: acute respiratory...
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Asbestosis

Asbestosis refers to later development of diffuse interstitial fibrosis secondary to asbestos fiber inhalation and should not be confused with other asbestos related diseases. Epidemiology Asbestosis typically occurs 10-15 years following the commencement of exposure to asbestos and is dose re...
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Hallux valgus

A hallux valgus (plural: halluces valgi) is a fixed abduction of the first metatarsophalangeal joint of the great toe. It is usually due to metatarsus primus varus which is a medial deviation or adduction of the first metatarsal with an increased first-second metatarsal angle. Radiographic feat...
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Intradural spinal lipoma

Intradural lipomas are a subset of spinal lipomas. They are typically intradural, subpial, juxtamedullary lesions 1 although they have occasionally been reported as entirely intramedullary lesions 2. Mature fatty tissue within the spinal dura can be seen in a number of entities: lipomyelocele/...
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Spinal dural arteriovenous fistula

Spinal dural arteriovenous fistulas (SDAVF) are the most common type of spinal vascular malformation, accounting for ~70% of all such lesions. This article specifically relates to spinal dural arteriovenous fistulas. For a discussion of intracranial dural arteriovenous fistulas refer to the mai...
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Metal-on-metal pseudotumor

A metal-on-metal pseudotumor, also known as aseptic lymphocyte-dominant vasculitis-associated lesion (ALVAL), is a mass-forming tissue reaction around a metal-on-metal hip or knee replacement. Clinical presentation Metal-on-metal pseudotumors are large focal solid or semiliquid masses around t...
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Intraductal papillary mucinous neoplasm

Intraductal papillary mucinous neoplasms or tumors (IPMNs or IMPTs) are epithelial pancreatic cystic tumors of mucin-producing cells that arise from the pancreatic ducts. They are most commonly seen in elderly patients.  On imaging, particularly MRCP, they are characterized by single or multipl...
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Chondroblastoma

Chondroblastomas, also referred as Codman tumors, are rare benign cartilaginous neoplasms that characteristically arise in the epiphysis or apophysis of a long bone in young patients. Despite being rare, they are one of the most frequently encountered benign epiphyseal neoplasms in skeletally im...
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Turbinectomy

A turbinectomy is a surgical procedure for partial or total removal of the - usually inferior - nasal concha, mainly to reduce the nasal airflow resistance. Indications A turbinectomy is usually performed to relieve chronic nasal obstruction secondary to: inferior turbinate hypertrophy aller...
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Superior thyroid cornu syndrome

Superior thyroid cornu syndrome refers to to a situation when there is precipitation of dysphagia and /or other symptoms as a hypertrophy +/- ossification of one of both the both of the superior horns (cornu) of the thyroid cartilage. This can also result from extreme medial deviation. Treatmen...
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Acromioclavicular injury

Acromioclavicular joint injuries are characterized by damage to the acromioclavicular joint and surrounding structures. Almost invariably traumatic in etiology, they range in severity from a mild sprain to complete disruption. Clinical presentation Acromioclavicular joint injuries usually occu...
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Diaphragmatic mesothelial cyst

Diaphragmatic mesothelial cysts are rare benign congenital lesions involving the diaphragm. They are thought to derive from from coelomic remnants.  Epidemiology They typically present in the pediatric population. Radiographic features CT Typically right sided and seen as a cystic mass betw...
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Bone marrow

Normal bone marrow is divided into red and yellow marrow, a distinction made on the grounds of how much fat it contains. Gross anatomy Red marrow is composed of: hematopoietic cells supporting stroma reticulum (phagocytes and undifferentiated progenitor cells) scattered fat cells a rich v...
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Osteochondroma

Osteochondromas are a relatively common imaging finding, accounting for 10-15% of all bone tumors and approximately 35% of all benign bone tumors. Although usually thought of as a benign bone tumor, they may be thought of as a developmental anomaly. They are frequently asymptomatic and have very...
Article

H-shaped vertebra

H-shaped vertebrae, also known as Lincoln log vertebrae, are a characteristic finding of sharply delimited central endplate depression, classically seen in approximately 10% of patients with sickle-cell anemia, and results from microvascular endplate infarction (figure 1) 3. It may occasionally...
Article

Sickle cell disease

Sickle cell disease (SCD) (historically known as drepanocytosis) is a hereditary (autosomal recessive) condition resulting in the formation of abnormal hemoglobin (a hemoglobinopathy), which manifests as multisystem ischemia and infarction, as well as hemolytic anemia.  Hemoglobin SC (HbSC) dis...
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Sickle cell disease (skeletal manifestations)

Skeletal manifestations of sickle cell disease result from three interconnected sequelae of sickle cell disease 5:  vaso-occlusive crises resulting in bone infarcts and subperiosteal hemorrhages chronic anemia resulting in expansion of the medullary spaces infection These, in turn, can predi...
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MR spectroscopy

The technique of magnetic resonance spectroscopy (usually shortened to MR spectroscopy or MRS) allows tissue to be interrogated for the presence and concentration of various metabolites. Grossman and Yousem said "If you need this to help you, go back to page 1; everything except Canavan (disease...
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Human coronavirus

The human coronaviruses (hCoVs), members of the family Coronaviridae, are enveloped RNA viruses that affect humans, mammals and birds, causing both acute and chronic illnesses. Four of the seven known human coronaviruses usually cause a mild coryzal illness only, these are HKU1, NL63, OC43, and...
Article

Neurodegenerative disease

A neurodegenerative disease is a blanket term encompassing a wide variety of disorders, typically slowly progressive, with variable gradual neurologic dysfunction.  Over the years numerous classifications schemas have been described, each adding a layer of confusion for students. The main disti...
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Scar endometriosis

Scar endometriosis is a term given to endometriosis occurring in a Cesarian section scar. It can be located in the skin, subcutaneous tissue, rectus muscle/sheath, intraperitoneally, or in the uterine myometrium (within uterine scar). Epidemiology The reported incidence of abdominal scar endom...
Article

Semimembranosus-tibial collateral ligament bursa

The semimembranosus-tibial collateral ligament bursa is located at the posteromedial aspect of the knee at the medial aspect of the semimembranosus tendon. It may also be known more simply as the semimembranosus bursa. It is distinct from the pes anserinus bursa, which is more closely related t...
Article

Elbow

The elbow is a complex synovial joint formed by the articulations of the humerus, the radius, and the ulna.  Gross anatomy Articulations The elbow joint is made up of three articulations 2,3: radiohumeral: capitellum of the humerus with the radial head ulnohumeral: trochlea of the humerus w...
Article

Ganglion cyst

Ganglion cysts are non-malignant cystic masses that occur in association with musculoskeletal structures. They are the most common soft tissue mass in the hand and wrist.  Terminology Ganglion cysts are sometimes also simply referred to as ganglia or a ganglion, but should not be confused with...
Article

Semitendinosus muscle

The semitendinosus is a fusiform muscle in the posterior compartment of the thigh and hamstrings muscles. It accompanies the semimembranosus muscle in the medial aspect of the posterior thigh. It is named for its cord-like tendon which forms half way down the thigh. Summary origin: ischial tub...
Article

Fetal sinus bradycardia

Fetal sinus bradycardia is a subtype of fetal bradycardia where the fetal heart rate is abnormally slow (<100 bpm) but runs at the regular rate with sinus rhythm. Pathology Associations congenital long QT syndrome 1 maternal anti Ro antibodies 2-3
Article

Fetal bradycardia

Fetal bradycardia refers to an abnormally low fetal heart rate, a potentially ominous finding. A sustained first trimester heart rate below 100 beats per minute (bpm) is generally considered bradycardic. The average fetal heart rate changes during pregnancy, however, and some consider the lower ...
Article

Elbow joint effusion

An elbow joint effusion is a key finding to recognize on an elbow radiograph and should be used as a trigger to search for a fracture.  Finding an effusion  Recognizing an elbow joint effusion on lateral radiographs is an essential radiology skill. While the fluid itself is not discretely seen...
Article

Photocathode

A photocathode is a negatively charged electrode in a light detection device such as the input screen in an image intensifier (II) that is coated with a photosensitive compound. When this is struck by light photons, the absorbed energy causes electron emission due to the photoelectric (PE) effec...
Article

Intestinal lymphangiectasia

Intestinal lymphangiectasia is a condition characterized by dilated intestinal lacteals causing loss of lymph into the lumen of the small intestine. This can result in hypoproteinemia, hypogammaglobulinemia, hypoalbuminemia and reduced number of circulating lymphocytes or lymphopenia.  Epidemio...
Article

Double contrast barium enema technique

Double contrast barium enema (DCBE) technique is a method of imaging the colon with fluoroscopy. "Double contrast" refers to imaging with the positive contrast of barium sulfate contrast medium (rarely water-soluble iodinated contrast) as well as with the negative contrast of gas (CO2 preferable...
Article

Pediatric renal tumors and masses

Pediatric renal tumors 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. Commoner lesions Wilms tumor: common in older children 1-8 years old nephroblastomatosis: ...
Article

Iodine

Iodine (chemical symbol I) is one of the trace elements. Its biological importance is its central place in the physiology of the thyroid gland and, in radiology, as the key chemical constituent of most of the radiographic, fluoroscopic, and CT contrast media. Chemistry Basic chemistry Iodine ...
Article

Cerebral blood volume (CBV)

Cerebral blood volume (CBV) (often relative CBV: see below) is one of the parameters generated by perfusion techniques (CT perfusion and MR perfusion). CBV is defined as the volume of blood in a given amount of brain tissue, most commonly milliliters of blood per 100 g of brain tissue 1. CBV ca...
Article

CT perfusion in ischemic stroke

CT perfusion in ischemic stroke has become established in most centers with stroke services as an important adjunct, along with CT angiography (CTA), to conventional unenhanced CT brain imaging. It enables differentiation of salvageable ischemic brain tissue (the penumbra) from the irrevocably ...
Article

3D ultrasound

Three-dimensional (3D) ultrasound is a technique that converts standard 2D grayscale ultrasound images into a volumetric dataset. The 3D image can then be reviewed retrospectively. The technique was developed for problem-solving (particularly in obstetric/gynecologic exams) and to potentially re...

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