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.

1,356 results found
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14-3-3 protein

14-3-3 protein is found in the cerebrospinal fluid (CSF), and is currently used to help identify patients with sporadic Creutzfeldt-Jakob disease (sCJD).  In diagnosing sCJD, the sensitivity of 14-3-3 protein is 92% and its specificity is 80% 1. A negative 14-3-3 assay may be helpful in reducin...
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1p19q codeletion

1p19q codeletion stands for the combined loss of the short arm chromosome 1 (i.e. 1p) and the long arm of chromosome 19 (19q) and is recognised as a genetic marker predictive of therapeutic response to both chemotherapy and combined chemoradiotherapy and overall longer survival in patients with ...
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2-hydroxyglutarate

2-hydroxyglutarate is a metabolite that accumulates in the brains of patients with IDH-1 mutated (IDH-1 positive) brain tumours, particularly diffuse low-grade gliomas. Although not in widespread clinical use, it is likely that 2-hydroxyglutarate, which resonates at 2.25 ppm, will be able to be ...
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Adenoma-carcinoma sequence

The adenoma-carcinoma sequence refers to a stepwise pattern of mutational activation of oncogenes (e.g. K-ras) and inactivation of tumour suppressor genes (e.g. p53) that results in cancer. An oncogene is a gene that has the potential to cause cancer. In tumour cells, these are often mutated or ...
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AFP reduction

Human AFP (alpha-fetoprotein) reduction is seen in pregnancy where it can be associated with:  certain chromosomal anomalies Down syndrome Turner syndrome trisomy 13 trisomy 18 Cornelia de-Lange syndrome 2
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Alzheimer type I glia

Alzheimer type I glia are a type of glial cell. They are large multinucleated astrocytes encountered in glial tumours and progressive multifocal leukoencephalopathy (PML) 1. 
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Alzheimer type II glia

Alzheimer type II glia are a type of glial cell. They are a pathological reactive astrocyte seen in the brain, unrelated to Alzheimer disease. They are seen most frequently in Wilson disease, but also in other systemic metabolic disorders, particularly those with elevated ammonia levels, typical...
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Arthrofibrosis

Arthrofibrosis is a complication of injury or trauma to a joint. It consists of excessive scar tissue formation within the joint capsule, resulting in pain, stiffness, and swelling that are greater than expected in the given clinical scenario. It has been most extensively studied in the knee, w...
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Aspergillus clavatus

Aspergillus clavatus is one of the species of Aspergillus that can cause pathology in humans. It is allergenic and causes a hypersensitivity pneumonitis called malt-workers lung. See also Aspergillus Aspergillus fumigatus Aspergillus flavus Aspergillus clavatus
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Astrocytes

Astrocytes are cells of the central nervous system which act as both physical and physiological support for the neurones that are embedded between them. They are particularly abundant in the grey matter, where they are the most abundant glial cells 1. They are highly branched and contribute to ...
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Atypical small acinar proliferation

Atypical small acinar proliferations (ASAP) are premalignant lesions of the prostate, which can be found in as many as 5% of prostate biopsies. They are suspicious glands without adequate histologic atypia to establish a definitive diagnosis of prostate cancer. Some studies showed that there is ...
Article

Bone contusion

Bone (marrow) contusion (bone bruising or bone marrow oedema) is an osseous injury which may result from compression of bone structures. Pathology Bone contusions represent microfractures with haemorrhage and can progress to osteochondritis dissecans 2. They typically appear within 48 hours of...
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CA-125

Serum CA-125 is well recognised as an ovarian cancer-associated marker and is an antigen determinant on a high-molecular-weight glycoprotein. The normal range of CA-125 is 0-35 U/mL. Serum CA-125 levels can also be used to monitor the response to treatment as well as a prognostic indicator sinc...
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CA 19-9 elevation

CA 19-9 (carbohydrate antigen 19-9 or cancer antigen) is a serum antigen (monosialoganglioside) that has increased diagnostic use in the management of several malignancies, mainly of hepatopancreaticobiliary origin. It is non-specific, however, and can rise in both malignant and non-malignant co...
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Carcinoembryonic antigen

Serum carcinoembryonic antigen (CEA) is a cell-adhesive glycoprotein that was discovered in colorectal cancer in 1965, and is hence one of the oldest and most used tumour markers. Its name derives from its normal expression in fetoembryonic liver, gut and pancreas tissue. Normal range of CEA is...
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Charcot-Leyden crystals

Charcot-Leyden crystals consist of collections of bipyramidal crystalloid made up of eosinophilic membrane proteins, which occur in:  asthma other eosinophilic lung disease 2 certain cases of sinusitis (e.g. allergic fungal sinusitis) They may be detected in the sputum or sinus secretions wi...
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Choristoma

A choristoma is simply a collection of microscopically normal cells or tissues in an abnormal location. This is different to a hamartoma which is derived only from local tissues. Examples include: adrenal choristoma (myelolipoma) nasopharyngeal choristoma facial nerve choristoma optic nerve...
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Chromogranin A

Chromogranin A (CgA) is an acidic secretory glycoprotein found in the secretory granules of neuroendocrine cells and neurones, as is a member of the granin family of proteins. It can be used both for immunohistochemical stains and as a serum marker 4.  Immunohistochemistry Chromogranin A is us...
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Circumferential resection margin

The circumferential resection margin (CRM) is a term used in rectal carcinoma excision surgery (such as total mesorectal excision (TME)). Pathologic evaluation of the resection margin on the excised rectum has been considered important for determining the risk of local recurrence. A margin of ≤...
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Columnar alteration with prominent apical snouts and secretions

Columnar alteration with prominent apical snouts and secretions (CAPSS) is a pathological entity encountered when breast biopsies are done for investigation of punctate or amorphous calcifications. CAPSS involves the terminal ductal and lobular units (TDLU's). It is sometimes classified under t...
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Cowdry bodies

Cowdry bodies are neuronal intranuclear inclusions seen in Herpes simplex virus infections.
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Cushing syndrome

Cushing syndrome is due to the effects of excessive glucocorticoids which may be exogenous or endogenous. Pathology In modern Western populations, iatrogenic steroid administration for treatment of inflammatory condition is the most common cause, e.g. asthma, rheumatoid arthritis. Endogenous ...
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Emphysematous pyelonephritis

Emphysematous pyelonephritis refers to a morbid infection of kidneys, with characteristic gas formation within or around the kidneys. If not treated early, it may lead to fulminant sepsis and carries a high mortality. Clinical presentation The patient usually presents with flank pain, urinary ...
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Empyema necessitans

Empyema necessitans (also sometimes spelt as empyema necessitasis) refers to extension of a pleural infection out of the thorax and into the neighbouring chest wall and surrounding soft tissues, e.g. extension of an empyema outwith the pleural cavity. Pathology It may either occur due the viru...
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Encephalitis lethargica

Encephalitis lethargica (EL) is a rare disease that is also known as von Economo encephalitis. It affects the midbrain and basal ganglia, and the exact aetiology is unknown.  Clinical presentation Symptoms are initially that of pharyngitis followed by lethargy, extrapyramidal movements (parkin...
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Encephalocele

Encephalocele, also known as meningoencephalocele, is a form of neural tube defect and a type of cephalocele where brain tissue and overlying meninges herniate out through a defect in the cranium.  Terminology It should be distinguished from cranial meningocele in which the lesion contains onl...
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Encephalomalacia

Encephalomalacia is term given to describe softening or loss of brain parenchyma with or without surrounding gliosis, as a late manifestation of injury.  Clinical presentation asymptomatic  serve as a focus of seizure Pathology Encephalomalacia is the end result of liquefactive necrosis of ...
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Enchondroma

Enchondromas (or chondromas 7) are a relatively common benign medullary cartilaginous neoplasm with benign imaging features. They account for the E in the popular mnemonic for bubbly bone lesions FEGNOMASHIC. They are sometimes classified under the umbrella term low grade chondral series tumours...
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Endocardial fibroelastosis

Endocardial fibroelastosis (EFE) is a rare cardiac condition which is classically described in the paediatric population (typically first two years). It is one of the causes for infants to present with unexplained heart failure.  Pathology The condition results from increasing amounts of fibro...
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Endocrine tumours of the pancreas

Endocrine tumours of the pancreas arise from the pancreatic islet cells and include some distinct tumours that match the cell type of origin.  Terminology Pancreatic endocrine tumours have commonly been referred to as "islet cell tumours", referring to the islets of Langerhans, from which they...
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Endogenous lipoid pneumonia

Endogenous lipoid pneumonia, also known as idiopathic lipoid pneumonia, is of the of the two types of lipoid pneumonias. It is also sometimes known as “cholesterol pneumonia” or “golden pneumonia” Please refer to the main article for a broad discussion, including clinical presentation, radiogra...
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Endolymphatic sac tumour

Endolymphatic sac tumours (ELST) are very rare, locally invasive tumours of endolymphatic sac. Early detection of these tumours is critical, because early surgical intervention may prevent further hearing loss. Endolymphatic sac tumours do not metastasize but are highly locally aggressive.  Epi...
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Endometrial atrophy

Endometrial atrophy is a response to a hypo-oestrogenic state. If it occurs after menopause it can be more specifically termed postmenopausal endometrial atrophy.  Clinical presentation While most patients are asymptomatic, endometrial atrophy is one of the commonest cause of postmenopausal bl...
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Endometrial carcinoma

Endometrial carcinoma is generally considered the most common gynaecological malignancy 1,5. It frequently presents with vaginal bleeding and both ultrasound and pelvic MRI are useful modalities for evaluation. Epidemiology Incidence peaks at around the 6th decade, though 12% of cases present ...
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Endometrial hyperplasia

Endometrial hyperplasia refers to an increased proliferation of the endometrial glands relative to the stroma. One of the main concerns is the potential malignant transformation of the endometrial hyperplasia to the endometrial carcinoma. Epidemiology Endometrial hyperplasia affects women of a...
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Endometrial stromal tumours

Endometrial stromal tumours (EST) are an uncommon group of tumours arising from endometrial stromal cells. It accounts for <2% of all uterine malignancies and 10% of all uterine sarcomas. Epidemiology Half occur in premenopausal women, with most patients presenting in the 5th decade. Clinical...
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Endometrial thickness

Endometrial thickness is a commonly measured parameter on routine gynaecological ultrasound and MRI. The appearance, as well as the thickness of the endometrium, will depend on whether the patient is of reproductive age or postmenopausal and, if of reproductive age, at what point in the menstrua...
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Endometrioid adenocarcinoma of the endometrium

Endometrioid carcinoma of the endometrium is the most common histological subtype of endometrial carcinoma accounts for 85-90% of cases. It is considered a type I carcinoma of the uterus with slow progression and relatively good prognosis. Patients are usually 55 to 65 years old.  Pathology En...
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Endometrioid carcinoma of the ovary

Endometrioid carcinomas of the ovary are a sub-type of epithelial ovarian tumours. The vast majority are malignant and invasive. On imaging, they are usually characterised as complex nonspecific solid-cystic masses and found associated with endometriosis.  Epidemiology Endometrioid carcinomas ...
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Endometriosis of canal of Nuck

Endometriosis affecting the canal of Nuck is an extremely rare site for endometriosis. It is proposed that retrograde implantation of endometrial tissue into patent canal of Nuck could give rise to the condition. Clinical presentation The condition is presented as a painful inguinal swelling. ...
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Endometritis

Endometritis refers to inflammation or infection involving the endometrium. Endometritis can be acute or chronic and may arise in an obstetric setting, such as following delivery or miscarriage, or in a nonobstetric setting due to pelvic inflammatory disease (PID) or endometrial instrumentation....
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Enostosis

An enostosis (pl. enostoses, also known as a "bone island") is a common benign bone lesion, usually seen as an incidental finding. They constitute a small focus of compact bone within cancellous bone. Enostoses can be seen on radiographs, CT, and MRI, and are considered one of the skeletal “don’...
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En plaque meningioma

En plaque meningiomas refer to a specific meningioma macroscopic appearance characterised by diffuse and extensive dural involvement, usually with extracranial extension into calvarium, orbit, and soft tissues. These tumours are thought to have a collar-like or sheet-like growth along the dura m...
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Entero-enteric fistula

An entero-enteric fistula is one formed between two parts of the small bowel. The can result for a number of reasons most commonly with inflammatory bowel disease, in particular Crohn.
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Enteropathic arthritis

Enteropathic arthritis (EA) is a form of chronic, inflammatory arthritis associated with the occurrence of an inflammatory bowel disease (IBD), and is classified as a form of seronegative spondyloarthropathy. Epidemiology Approximately 20% of people with Crohn disease or ulcerative colitis may...
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Eosinophilic fasciitis

Eosinophilic fasciitis (EF), also known as Shulman syndrome, is an uncommon connective tissue disorder. Epidemiology It can potentially present at age. There is a recognized female predilection 3-4. Clinical presentation Patients typically present with pronounced extremity oedema and skin in...
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Eosinophilic gastroenteritis

Eosinophilic gastroenteritis (EG) is an uncommon disease characterised by diffuse infiltration of any or all layers of gut wall by eosinophils.  Epidemiology  EG is an uncommon but not rare disease with slight male predominance. It can affect any age group but usually patients present in their...
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Ependymal cells

Ependymal cells are one of the four main types of glial cells, and themselves encompass three types of cells 1:  ependymocytes: line the ventricles of the brain and central canal of the spinal cord tanycytes: line the floor of the third ventricle choroidal epithelial cells: line the surface o...
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Ependymal rosettes (ependymoma)

Ependymal rosettes correspond to a histologic architectural pattern that very characteristic of ependymomas, as tumour cells form structures similar to the lining of normal ventricles. They are characterised by a halo or spoke-wheel arrangement of tumour cells surrounding an empty central tubule...
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Ependymocytes

Ependymocytes are one of the three types of ependymal cells, which in turn are one of the four principles types of glial cells, and are found lining the ventricular system of the brain and the central canal of the spinal cord 1.  They do not form a water-tight barrier between the cerebral spina...
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Epidermal inclusion cyst

Epidermal inclusion cysts are common cutaneous lesions that represent proliferation of squamous epithelium within a confined space in the dermis or subdermis. Terminology Synonyms include "epidermoid cyst" and "epidermoid inclusion cyst". These are occasionally termed "sebaceous cyst", althoug...
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Epididymitis

Epididymitis refers to inflammation of the epididymis, and may be associated with inflammation extending to the testis itself, in which case the term epididymo-orchitis is used. This should be distinguished from isolated orchitis, which is by comparison much less common.  Epidemiology There ar...
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Epidural angiolipoma

Epidural angiolipomas are rare benign tumours composed of mature adipocytes and abnormal vessels.  Epidemiology Epidural angiolipomas are more frequently encountered in women, and typically in middle age (40-50 years of age) 1.  Clinical presentation In keeping with the slow growth of these ...
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Epiglottitis

Epiglottitis is a life-threatening condition caused by inflammation of the epiglottis and aryepiglottic folds 1,  which can lead to acute airway obstruction. Hence, treatment should be urgent and performed by appropriately trained individuals, e.g. instrumentation of the trachea should be perfor...
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Epignathus

Epignathus is a term given to a very rare form of teratoid tumour that arises from the oropharyngeal region. Epidemiology There may be a slight female predilection ref. The estimated incidence is ~ 1 in 35,000 to 200,000 births. Clinical presentation The tumour classically presents in utero ...
Article

Epipericardial fat necrosis

Epipericardial fat necrosis is a rare self-limiting cause of an acute chest pain in an otherwise healthy individuals. It occurs within the mediastinum outside the pericardium. Clinical presentation The patient presents with an acute chest pain that may mimic other cardiopulmonary causes. It is...
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Epiphrenic diverticulum

Epiphrenic diverticula are pulsion diverticula of the distal oesophagus arising just above the lower oesophageal sphincter, more frequently on the right posterolateral wall. They are less frequent than traction mid oesophageal diverticula, but may have more clinical relevance.   Clinical prese...
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Epispadias

Epispadias is a rare congenital anomaly that is almost always associated with bladder exstrophy.  Epidemiology It occurs in 1 in 30,000 births, with a male: female ratio of 3:1. Clinical presentation The roof of the urethra is absent and the urethra opens anywhere between the base and the gl...
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Epithelial membrane antigen (EMA)

Epithelial membrane antigen (EMA) is a commonly used target for immunohistochemisty, found on the surface of many epithelial cells and thus present in a wide variety of tumours. It also is sometimes seen within the cytoplasm of cells (e.g. perinuclear dot in ependymomas). 
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Epithelial-myoepithelial carcinoma of lung

Epithelial-myoepithelial carcinoma of lung is a very rare type of lung carcinomas of the salivary gland type. Pathology Diagnosis is based on the identification of myoepithelial cells, with spindle cells, clear cells, or plasmacytoid differentiation or a mixture of phenotypes, along with a var...
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Epithelioid glioblastoma

Epithelioid glioblastoma is a variant of glioblastoma (along with gliosarcoma and giant cell glioblastoma) only recently added to the WHO classification of CNS tumours as part of the 2016 update 1.  Terminology Whether or not epithelioid glioblastomas are distinct from rhabdoid glioblastomas i...
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Epithelioid haemangioendothelioma

Epithelioid haemangioendothelioma (EHE) is a rare relatively low grade vascular tumour. It occurs around medium to large venous structures. Pathology It consists of rounded or slightly spindle-shaped eosinophilic endothelial (epitheloid) cells with rounded nuclei and prominent cytoplasmic vacu...
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Erb palsy

Erb palsy, also known as brachial plexus birth palsy, is a form of obstetric brachial plexus injury as a result of complications during delivery.  Clinical presentation The most common cause is due to excessive lateral traction or stretching of the fetal head and neck in opposite directions du...
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Erdheim-Chester disease

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell, non-familial multisystemic granulomatosis, with widespread manifestations and of highly variable severity. The most common presenting symptom is bone pain. Epidemiology Erdheim-Chester disease is a rare, non-inherited disease of midd...
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Erdheim-Chester disease (pulmonary manifestations)

Pulmonary manifestations of Erdheim-Chester disease are uncommon. Epidemiology The lungs are affected in ~25% (range 20-35%) of cases 5.  Radiographic features HRCT chest Described findings include 1 symmetric reticular interstitial opacities smooth interlobular septal thickening and fiss...
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Essential thrombocythaemia

Essential thrombocythaemia (ET) refers to an acquired myeloproliferative neoplastic state characterised by an expansion of the megakaryocytic lineage, leading to an isolated elevation of platelets. It falls under the group of myeloproliferative disorders. It increases the risk of both thrombosis...
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Ethmocephaly

Ethmocephaly refers to a rare type of midline cranio-facial anomaly that is characterised by the presence of extreme hypotelorism, arrhinia and a midline proboscis.  Pathology Associations holoprosencephaly 1-2: particularly alobar holoprosencephaly See also cebocephaly
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Eustachian tube dysfunction

Eustachian tube dysfunction (ETD) is considered by many to be the underlying cause of chronic otomastoiditis, although both the exact pathogenesis and role of ETD in chronic middle ear infections is unclear. Epidemiology ETD is estimated to be present in ~1% of the adult population. Pathology...
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Ewing sarcoma

Ewing sarcoma is the second most common highly malignant primary bone tumour of childhood after osteosarcoma, typically arising from medullary cavity with invasion of Haversian system. They usually present as moth-eaten destructive permeative lucent lesions in the shaft of long bones with large ...
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Ewing sarcoma (chest wall)

Ewing sarcoma family of tumours (ESFT), also referred as Ewing sarcomas of the chest wall, are malignant tumours affecting children and young adults, originating either from the osseous structures or the soft tissues of the chest wall.  On imaging, they are usually characterised as a large extr...
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Excessive lateral pressure syndrome

Excessive lateral pressure syndrome (ELPS) is abnormal  lateral tilt of the patella without lateral translation and considered one of the relatively common causes of anterior knee pain. It can affect both adolescents or adults. Patients usually present with insidious onset anterior knee pain agg...
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Exencephaly

Exencephaly is a lethal congenital fetal brain developmental anomaly (neural tube defect) considered to be a precursor to anencephaly in the acrania-exencephaly-anencephaly sequence. Pathology It is characterised by calvarial absence and loss of fetal brain tissue to variable degrees and is co...
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Exophytic hepatic mass

Exophytic hepatic mass or tumour is a lesion which predominantly lies outside the margins of liver but originates from within the liver. Pathology Causes include 1: benign  hepatic haemangioma hepatic adenoma hepatic cyst hepatic angiomyolipoma focal nodular hyperplasia malignant  hepa...
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Exostosis

Exostoses are defined as benign growths of bone extending outwards from the surface of a bone. It can occur in any bone and be triggered by a number of factors. There are a number of examples of exostoses that occur due to local irritant stimuli: ivory exostosis exostosis of the external audit...
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Extensive intraductal component (invasive ductal carcinoma)

Extensive intraductal component (EIC) in breast imaging evaluation is the pathological description where an invasive ductal carcinoma has a prominent intraductal component within it or if there is intraductal carcinoma, DCIS is present within sections of normal adjacent tissue. It is sometimes c...
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External auditory canal cholesteatoma

External auditory canal cholesteatomas are an uncommon locations for cholesteatomas, which are usually in the middle ear or petrous apex.  When they occur lateral to the tympanic membrane, they are referred to as external auditory canal cholesteatomas.   Epidemiology The external acoustic cana...
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External auditory canal osteoma

External auditory canal osteoma is a rare focal pedunculated bony overgrowth of the osseous external auditory canal. Radiographic features solitary pedunculated bony overgrowth of the external auditory canal usually at the bony cartilaginous junction unilateral large lesions may be associate...
Article

Extracranial meningioma

Extracranial meningiomas, also known as primary extradural meningiomas or ectopic meningioma, are a rare location-specific type of meningioma that arise outside the dural covering of the brain and spinal cord. They are essentially extracranial tumours, most often occurring in the head and neck, ...
Article

Extramedullary hematopoiesis in the adrenal gland

Extramedullary hematopoiesis (EMH) is a physiologic compensatory event in many hematologic diseases. It occurs most commonly in the spleen, liver, and lymph nodes and less frequently in the lung, pleura, breast, thymus, small bowel, and central nervous system.1  EMH in the adrenal is uncommon,2...
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Extramedullary plasmacytoma

Extramedullary plasmacytoma (EMP) is an uncommon plasma cell tumour that is composed of monoclonal plasma cells arranged in clusters or sheets. The rate of progression to multiple myeloma (MM) varies from 10% to 30%. Epidemiology EMP occurs most commonly during the fourth through to seventh de...
Article

Extramural vascular invasion

Extramural vascular invasion (EMVI) is the direct invasion of a blood vessel (usually a vein) by tumour. In rectal cancer, this can occur on a macroscopic level and be detected on staging MRI. It is a significant prognostic factor, being a predictor of haematogenous spread.  Radiographic featur...
Article

Extrapleural haematoma

Extrapleural haematomas are uncommon and usually seen in the context of rib fracture, subclavian venous catheter traumatic insertion, and blunt chest injury. Pathology Extrapleural haematomas result from the accumulation of blood in the extrapleural space where the overlying extrapleural fat i...
Article

Extrapontine myelinolysis

Extrapontine myelinolysis (EPM) is one of the complications occurring secondary to rapid correction of hyponatraemia, and is, along with central pontine myelinolysis encompassed by the more recent term osmotic demyelination syndrome. In the vast majority of cases it is associated with central p...
Article

Extrapulmonary tuberculosis

Extrapulmonary tuberculosis (TB) refers to the haematogenous spread of Mycobacterium tuberculosis. Pathology Extrapulmonary tubercuosis can occur as a primary form of the disease, i.e. direct infection of an extrapulmonary organ without the presence of primary pulmonary tuberculosis or it can ...
Article

Extraskeletal Ewing sarcoma

Extraskeletal Ewing sarcoma (EES) is included in the Ewing sarcoma family of tumors (ESFT) along with Ewing sarcoma of bone, primitive neuroectodermal tumor (PNET), peripheral neuroepithelioma, and thoracopulmonary PNET (Askin tumour). When compared with Ewing sarcoma of bone, extraskeletal Ewin...
Article

Extra skeletal osteosarcoma

Extraskeletal osteosarcoma (ESOS) is a rare mesenchymal malignant tumour that occurs in the retroperitoneum and soft tissue of extremities without any attachment to bone. Epidemiology ESOS in contrast to other subtypes of osteosarcoma occurs infrequently in individuals under 40 years of age, m...
Article

Exudative retinitis

Exudative retinitis (also known as retinal telangiectasis or Coats disease) is a rare congenital disease affecting the eyes and is a cause of leukocoria. Epidemiology The exact aetiology is unknown and the disease is a non hereditary disorder.  It occurs predominantly in young males, with the ...
Article

Fabry disease

Fabry disease is a multisystem disorder which results from an X-linked inborn error of metabolism. The disease is characterised by a deficiency in hydrolase alpha-galactosidase activity with a resultant abnormal accumulation of globotriaosylceramide (Gb3) in various organ systems. In men, the co...
Article

Facial nerve choristoma

Facial nerve choristomas are rare, being characterised by non-neoplastic proliferation of smooth muscle cells and fibrous tissue. Facial nerve choristomas presumably can occur anywhere along the course of the facial nerve (CN VII), although the only cases reported are in the internal acoustic me...
Article

Factitious hyperthyroidism

Factitious hyperthyroidism or thyrotoxicosis factitia refers to precipitation of thyrotoxicosis due to exogenous ingestion of thyroid hormone (e.g. levothyroxine). It has been rarely associated with myocardial ischaemia 2. Radiographic features Ultrasound The hypervascularity which is seen wi...
Article

Faecaloma

A faecaloma is a mass of faeces most frequently noted in the rectum and sigmoid colon, that is much harder than a faecal impaction due to coprostasis. Pathology Usually, the faecal matter accumulates in the intestine, then stagnates and increases in volume until the intestine becomes deformed ...
Article

Falx ossification

In discussing mineralisation of the falx cerebri, many radiology textbooks use the term falx calcification and make no mention of falx ossification.  Epidemiology Ossification of dural folds is relatively unusual; one study suggested a prevalence of falx ossification of 0.7% 1. Even though, os...
Article

Familial adenomatous polyposis syndrome

Familial adenomatous polyposis syndrome (FAPS) is characterised by the presence of hundreds of adenomatous polyps in the colon. It is the most common of the polyposis syndromes. Terminology Familial polyposis coli, attenuated familial adenomatous polyposis and Gardner syndrome are all variants...

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