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.

1,793 results found
Article

Globe rupture

Globe rupture is an ophthalmologic emergency. A ruptured globe or an open-globe injury must be assessed in any patient who has suffered orbital trauma because open-globe injuries are a major cause of blindness. In a blunt trauma, ruptures are most common at the insertions of the intraocular mus...
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Globus pharyngeus

Globus pharyngeus is the subjective feeling of a lump in the throat which can have a variety of causes. In modern practice globus is often evaluated by flexible nasoendoscopy in the first instance since many patients present to otolaryngology services. If no cause is identified or if nasoendosco...
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Glomus tympanicum paraganglioma

Glomus tympanicum paragangliomas (chemodectomas) are the most common middle ear tumour.  Epidemiology There is a female predominance (M:F = 1:3); presentation is most common when patients are more than 40 years old 1,2.  Clinical presentation May be incidental but symptomatic masses produce ...
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Glucagonoma

Glucagonomas are pancreatic endocrine tumours that secrete glucagon. Most lesions are malignant. Epidemiology They are rare with an incidence of 0.000005%. Equal incidence in middle-aged men and women.  Clinical presentation Most patients present with a necrolytic migratory rash and various ...
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Gluteal injection site granuloma

Gluteal injection site granulomas are a very common finding on CT and plain radiographs. They occur as a result of subcutaneous (i.e. intra-lipomatous) rather than intramuscular injection of drugs, which cause localised fat necrosis, scar formation and dystrophic calcification. Once familiar wi...
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Gnathic osteosarcoma

Gnathic osteosarcoma is a subtype of osteosarcoma that primarily affects the mandible (horizontal ramus) and maxilla (alveolar ridge, sinus floor, and palate). Epidemiology represents ~6% of osteosarcomas 3  60% in males has an older onset (~30 years) and a peak incidence: 30-40 years Clini...
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Goitre

Goitre refers to enlargement of the thyroid gland. It can occur from multiple conditions. The definition of a goitre depends on age and sex; below are the upper limits of normal for thyroid gland volume 1: adult males: 25 mL adult females: 18 mL 13-14 years: 8-10 mL 3-4 years: 3 mL neonate...
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Gosselin fracture

The Gosselin fracture is a fracture of distal tibia with a V-shaped fractured fragment and intraarticular involvement. History and etymology It is named after Leon Athanese Gosselin (1815–1887), a French surgeon.
Article

Gossypiboma

A gossypiboma, also called textiloma or cottonoid, refers to a foreign object, such as a mass of cotton matrix or a sponge, that is left behind in a body cavity during an operation. It is an uncommon surgical complication. The manifestations and complications of gossypibomas are so variable tha...
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Gout

Gout is a crystal arthropathy due to deposition of monosodium urate (MSU) crystals in and around the joints. Epidemiology Typically occurs in those above 40 years. There is a strong male predilection of 20:1. Pathology Characterised by monosodium urate crystals deposition in periarticular so...
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Graft versus host disease

Graft versus host disease (GvHD) is a frequent complication of allogeneic post haematopoietic stem cell transplantation (HSCT), commonly known as bone marrow transplantation. Anti-rejection drugs have reduced the incidence, although it does still frequently occur.  Pathology GvHD can present e...
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Graft versus host disease (pulmonary manifestations)

Pulmonary graft versus host disease (GvHD) is one of the thoracic manifestations that can complicate haematopoetic stem cell transplantation. Pulmonary GvHD can be broadly divided into acute and chronic disease 1-4: acute pulmonary GvHD pulmonary involvement is rare the median time of onset o...
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Granular cell tumour of the breast

A granular cell tumour (GCT) of the breast is an uncommon, usually benign tumour which is possibly of neural origin. Epidemiology They tend to occur at a younger age than other types of breast cancer 4. The age range of presentation, however, can be very variable although they occur more commo...
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Granular cell tumour of the pituitary region

Granular cell tumour of the pituitary region, also known as a pituitary choristoma, are rare low-grade tumours of the posterior pituitary and infundibulum.  Terminology Care must be taken when reading older literature as granular cell tumours of the pituitary region, and alternative names incl...
Article

Granulocytic sarcoma

Granulocytic sarcoma (also called myeloid sarcoma and chloroma) is a rare neoplasm comprised of myeloid precursor cells. It can occur in association with: acute myeloid leukaemia (AML) chronic myeloid leukaemia (CML) other myeloproliferative disorders such as myelofibrosis with myeloid meta...
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Granuloma annulare

Granuloma annulare is a benign idiopathic inflammatory disorder of the dermis, characterised by formation of dermal papules in young children. Clinical presentation Granuloma annulare has various clinical presentations: three cutaneous forms erythematous perforating generalised one subcut...
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Granulomatosis with polyangiitis

Granulomatosis with polyangiitis (GPA), previously known as Wegener granulomatosis, is a multisystem systemic necrotising non-caseating granulomatous vasculitis affecting small to medium sized arteries, capillaries and veins, with a predilection for the respiratory system and kidneys 3. This ar...
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Granulomatosis with polyangiitis (breast manifestations)

Breast involvement in granulomatosis with polyangiitis is seen in patients with avid systemic manifestations.  Clinical presentation Clinically they can mimic carcinoma as a palpable, tender mass. Pathology Granulomatosis with polyangiitis (or formerly known as Wegeners granulomatosis) is a ...
Article

Granulomatosis with polyangiitis (orbital manifestations)

Ophthalmologic manifestations of granulomatosis with polyangiitis (GPA) (previously known as Wegener's granulomatosis), both ocular and orbital, have been reported in 40-50% of GPA patients 1-3 and can occur in either the classic or limited form of the disease. 4 Ophthalmologic disease occasiona...
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Granulomatosis with polyangiitis (pulmonary manifestations)

This article discusses the pulmonary manifestations of granulomatosis with polyangiitis (previously known as Wegener's granulomatosis). It is classified as a type of pulmonary angiitis and granulomatosis. For a general discussion of the condition, please refer to the main article on granulomato...
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Granulomatosis with polyangiitis (renal manifestations)

The renal manifestations of granulomatosis with polyangiitis (GPA) (previously known as Wegener's granulomatosis) are occult on imaging, especially when compared to the pulmonary changes. Approximately half of GPA patients have kidney disease at presentation. Granulomatosis with polyangiitis (We...
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Granulomatosis with polyangiitis (upper respiratory tract manifestations)

The upper respiratory tract manifestations of granulomatosis with polyangiitis (GPA) (previously known as Wegener's granulomatosis) are common and affect most patients. . Granulomatosis with polyangiitis (Wegener granulomatosis), is a multi-system systemic necrotizing non-caseating granulomatous...
Article

Granulomatous invasive fungal sinusitis

Granulomatous invasive fungal sinusitis, sometimes termed granulomatous invasive fungal sinusitis, is a form of invasive fungal sinusitis. Reports describing the imaging findings have been uncommon 1. Epidemiology It is rare and been mainly reported in Sudan, India, Pakistan and sometimes in t...
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Granulomatous lung disease

Granulomatous lung disease refers a broad group of infectious and well as non infections conditions characterised by formation of granulomas. The spectrum includes infectious mycobacterial pulmonary tuberculosis pulmonary non tuberculous mycobacterial infection fungal pulmonary coccidioid...
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Granulomatous mastitis

Granulomatous mastitis is a very rare breast inflammatory disease of unknown origin that can clinically mimic carcinoma of the breast. Clinical presentation The condition generally manifests as a distinct, firm to hard mass that may involve any part of the breast. The subareolar regions may be...
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Granulomatous prostatitis

Granulomatous prostatitis is a nodular form of chronic prostatitis. It is usually diagnised by biopsy. Pathology Causes idiopathic infection iatrogenic: (BCG,post radiation) systemic disease such as sarcoidosis  autoimmune diseases Subtypes One form of classificiations is as nonspecif...
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Graves disease

Graves disease is an autoimmune thyroid disease and is the most common cause of thyrotoxicosis (up to 85%). Epidemiology There a strong female predilection with the F:M ratio of at least 5:1. Typically presents in middle age. Clinical presentation Patients are thyrotoxic. Extra-thyroid manif...
Article

Growth arrest lines

Growth arrest lines (also known as growth resumption lines or Harris lines) are alternating transverse rings of sclerosis at the metaphysis of a long bone. Pathology The radiographic finding occurs from alternating cycles of osseous growth arrest and growth resumption. This appears to result f...
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Gymnast wrist

Gymnast wrist is defined as a chronic stress fracture (Salter Harris type I) of the distal radial (and less commonly ulnar) growth plate. It is most commonly seen in young individuals involved in gymnastics. Radiographic features physeal plate irregularity physeal plate widening cystic chang...
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H1N1 influenza

H1N1 influenza is a strain of influenza that notably resulted in a pandemic in 2009. Pathology It is type of influenza A virus of swine origin. Clinical presenation There can be a wide spectrum of clinical syndromes with patient's ranging from being asymptomatic to having fulminating viral p...
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Haemangiopericytoma

Haemangiopericytoma is a term formerly used to describe a continuum of mesenchymal tumours with elevated cellularity found throughout the body in soft tissue and bone. After many years of controversy, haemangiopericytomas have been shown to not only share histological features similar to solitar...
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Haemangiopericytoma of the spleen

Haemangiopericytomas of the spleen are a very rare vascular neoplasm with only a few case reports available at the time of writing. Clinical presentation Splenic haemangiopericytomas are typically asymptomatic or can result in splenomegaly. Pathology These are a soft tissue vascular neoplasm...
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Haemarthrosis

Haemarthosis is haemorrhage into a joint space and can be regarded as a subtype of a joint effusion. Trauma is by far the most common cause of a haemarthosis. Other causes include bleeding disorders, neurological deficits, arthritis, tumours and vascular damage. Lipohaemarthrosis is a result o...
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Haematuria (adult)

Haematuria occurs when blood enters the urinary collecting system. There are many aetiologies for haematuria, and they range from benign and transient to gravely concerning. Haematuria can derive from the kidneys, ureters, bladder, prostate (in men), or urethra. Imaging can often be useful to de...
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Haemochromatosis (cardiac manifestations)

Cardiac involvement in haemochromatosis typically occurs with primary haemochromatosis, as the organ is usually spared in the secondary form of the disease. Epidemiology Cardiac involvement occurs in approximately 15-20% of the patients with haemochromatosis.  Clinical presentation Manifesta...
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Haemochromatosis (pancreatic manifestations)

Pancreatic manifestations of haemochromatosis typically occur with primary haemochromatosis, as the organ is usually spared in the secondary form of the disease.  Pathology Iron deposition can occur in the pancreas with primary hemochromatosis. Pancreatic involvement is uncommon in patients wi...
Article

Haemopericardium

Haemopericardium refers to the presence of blood within the pericardial cavity, i.e. a sanguineous pericardial effusion. If enough blood enters the pericardial cavity, then a potentially fatal cardiac tamponade can occur.  Pathology Aetiology There is a very long list of causes 1,4 but some o...
Article

Haemophilia

Haemophilia is an inherited bleeding disorder which is X-linked recessive and therefore occurs almost exclusively in males. There are two subtypes - haemophilia A (80%) and haemophilia B (20%).  Epidemiology The incidence of haemophilia A is around 1 in 5000 male births, and the incidence of h...
Article

Haemophilic arthropathy

Haemophilic arthropathy refers to permanent joint disease occurring in haemophilia sufferers as a long-term consequence of repeated haemarthrosis.  Around 50% of patients with haemophilia will develop a severe arthropathy. Epidemiology Haemophilia is an x-linked recessive disease affecting mal...
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Haemophilic pseudotumour

Haemophilic pseudotumour is a rare complication of haemophilia consisting of a progressive cystic swelling of muscle and/or bone, occurring in less than 2% of haemophiliacs.  Epidemiology It is reported in 1-2% of haemophiliacs patients.  Pathology Most develop in the muscles of the pelvis a...
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Haemorrhagic cholecystitis

Haemorrhagic cholecystitis refers to an inflammatory process of the gallbladder, complicated by haemorrhage into the lumen.  Clinical presentation The presenting features may mimic non-haemorrhagic acute cholecystitis, with right upper quadrant pain being a dominant feature. If the blood is pa...
Article

Haemorrhagic ovarian cyst

Haemorrhagic ovarian cysts (HOCs) usually result from haemorrhage into a corpus luteum or other functional cyst. Radiographic features are variable depending on the age of the haemorrhage. They typically resolve within eight weeks.  Clinical presentation Patients may present with sudden-onset ...
Article

Haemorrhagic pancreatitis

Haemorrhagic pancreatitis is a possible uncommon complication that can occur with pancreatitis and is characterised by bleeding within or around the pancreas. It is usually considered a late sequela of acute pancreatitis. Pathology Haemorrhage can occur in patients with severe necrotising panc...
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Haemosuccus pancreaticus

Haemosuccus pancreaticus, also known as pseudohaemobilia or haemoductal pancreatitis, is defined as upper gastrointestinal tract haemorrhage originating from the pancreatic duct into the duodenum via the ampulla of Vater, or major pancreatic papilla. Epidemiology male:female ratio is 7:1 high...
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Haggitt level

The Haggitt level is a histopathological term used for describing the degree of infiltration from a malignant polypoidal lesion. Levels of invasion 0: carcinoma in situ or intramucosal carcinoma 1: invasion of the submucosa, but limited to the head of the polyp 2: invasion extending into the...
Article

Halitosis

Halitosis refers to the symptom of foul oral odour, commonly termed "bad breath", that patients can present with, usually to dental services. Pathology It is thought to be caused by the presence of volatile sulphur compounds that are produced by bacteria. Although the underlying cause can be s...
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Hallux rigidus

Hallux rigidus (osteoarthrosis with restricted motion) is the second most common disabling deformity of the first metatarsophalangeal joint after hallux valgus. Epidemiology It is most commonly seen in middle-aged patients, but can develop during adolescence. Unlike a hallux valgus, males appe...
Article

Hand-Schüller-Christian

Hand-Schüller-Christian disease is a clinically intermediate form of a spectrum of histiocytic disorders, which ranges from acute fulminant to chronic indolent disease. It primarily affects children, less often young adults, and rarely older adults. Hand-Schüller-Christian disease has been desc...
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Hashimoto thyroiditis

Hashimoto thyroiditis, also known as lymphocytic thyroiditis or chronic autoimmune thyroiditis, is a subtype of autoimmune thyroiditis. It is one of the most common thyroid disorders.  Epidemiology Typically affects middle aged females (30-50 year age group with a F:M ratio of 10-15:1).  Clin...
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Head and neck squamous cell carcinomas

Head and neck squamous cell carcinomas (HNSCC) refer to SCCs of the aerodigestive tract of the head and neck rather than cutaneous SCCs. SCC is the most common tumour of the mucosa of the upper aerodigestive tract, and can occur anywhere there is squamous cell mucosa.  Epidemiology, risk factor...
Article

Heberden node

Heberden nodes are a clinical examination sign related to the hands, most commonly found at the dorsolateral aspect of the distal interphalangeal joint (DIPJ) and are a moderate-to-strong marker of osteoarthritis 1-2.   Previously Heberden nodes and DIP osteophytes were thought to be synonymous...
Article

Hemifacial hypertrophy

Hemifacial hyperplasia or hemifacial hypertrophy is a rare developmental anomaly characterised by asymmetric growth of hard and soft tissues of the face 1. Epidemiology These asymmetries are often noted at birth and are usually accentuated with increasing age, especially around puberty 2. The...
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Hemimegalencephaly

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

Hepascore is a biochemical severity scoring system based on liver function tests in predicting the extent of liver fibrosis/cirrhosis in patients with hepatitis C infection. Hepascore may also be applicable to other liver diseases and is being trialed for fatty liver disease and hepatitis B infe...
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Hepatic and splenic tuberculosis

Hepatic and splenic tuberculosis refers to tuberculosis affecting liver and spleen. It generally occurs due to spread from primary site of infection, commonly from pulmonary tuberculosis. Pathology Two types of lesions are known: micronodular (common) macronodular (rare) Radiographic featur...
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Hepatic angiomyolipoma

Angiomyolipoma (AML) is an uncommon benign hamartomatous hepatic mass lesion, containing blood vessel (angioid), smooth muscle (myoid) and mature fat (lipoid) components. There is an association with tuberous sclerosis, although this is less strong than for renal AMLs. Clinical presentation Mo...
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Hepatic angiosarcoma

Hepatic angiosarcoma is a rare malignancy but is still the third most common primary liver tumour. They have a variable appearance on both CT and MRI reflecting the pleomorphic histological nature. Prognosis is very poor, with survival uncommon beyond one year from diagnosis.  Terminology Hepa...
Article

Hepatic carcinoid

Primary hepatic carcinoid is an extremely rare type of carcinoid tumor, with somewhere between 60-90 cases reported in the literature. Metastatic carcinoid tumor from the gastrointestinal tract to the liver is far more common. Clinical presentation Some patients present with carcinoid syndrome...
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Hepatic carcinosarcoma

Hepatic carcinosarcoma is a very rare tumour that is defined by mixed histological features.  Terminology This tumour has also been referred to as malignant mixed tumour, spindle cell carcinoma, pseudosarcoma or sarcomatoid carcinoma 1,2.  Pathology Hepatic carcinocarcinoma contain a mixture...
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Hepatic encephalopathy

Hepatic encephalopathy (also known as portosystemic encephalopathy) refers to a spectrum of neuropsychiatric abnormalities occurring in patients with liver dysfunction and portal hypertension. It results from exposure of the brain to excessive amounts of ammonia. Terminology Hepatic encephalop...
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Hepatic haemangioma

Hepatic haemangiomas, also known as hepatic venous malformations, are benign non-neoplastic hypervascular liver lesions. They are frequently diagnosed as an incidental finding on imaging, and most patients are asymptomatic. From a radiologic perspective, it is important to differentiate haemangi...
Article

Hepatic haemosiderosis

Hepatic haemosiderosis refers to the deposition of haemosiderin in the liver. Pathology Hepatic iron overload can be in the form of 7 diffuse heterogeneous segmental focal hypersiderosis intralesional siderosis periportal siderosis. In the absence of genetic haemochromatosis and system...
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Hepatic inflammatory pseudotumour

Hepatic inflammatory pseudotumours (IPT) are rare benign hepatic lesions. Epidemiology Most common in young adults with males affected more than females 7.  Pathology Aetiology is unknown 7.  Macroscopic appearance Hepatic IPT is often seen as a well-circumscribed, encapsulated inflammator...
Article

Hepatic leiomyosarcoma

Hepatic leiomyosarcomas are rare primary malignant tumors derived from smooth muscle cells in the liver. Epidemiology Hepatic leiomyosarcoma is rare 1. An equal sex distribution and a broad age range (5 months-66Y) has been reported. Some have suggested an associated with AIDS 2. Pathology T...
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Hepatic lymphoma

Hepatic lymphoma is a rather broad term given to any form of hepatic involvement with lymphoma. This can be broadly divided into: secondary hepatic involvement with lymphoma: most common by far, many tend to be non-Hodgkin lymphoma (NHL) 1 primary hepatic lymphoma: extremely rare Pathology R...
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Hepatic mesenchymal hamartoma

Hepatic mesenchymal hamartoma is an uncommon benign hepatic tumour. Some authors even consider this to be a developmental anomaly rather than a cystic neoplasm 9,12. Epidemiology It typically occurs in children and neonates, with most cases presenting within the first two years of life 3. Ther...
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Hepatic peliosis

Hepatic peliosis is a rare benign vascular condition characterised by dilatation of sinusoidal blood filled spaces within the liver.  There may be involvement of other organs, most commonly the spleen and bone marrow.  It can be seen in a variety of settings and is important as appearances may m...
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Hepatic solitary fibrous tumour

Hepatic solitary fibrous tumours (hepatic SFTs) are rare mesenchymal tumours. Epidemiology Fewer than 60 cases have been reported in the literature. Female predominance (~70%). There is a mean age of 52 years at presentation, but a wide range of incidence (16-84 years). Clinical presentation ...
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Hepatic veno-occlusive disease

Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), is a condition arising from occlusion of hepatic venules. Clinical presentation right upper quadrant pain painful hepatomegaly ascites abnormal liver function tests Pathology Toxic injury to liver s...
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Hepatisation of the gallbladder

Hepatisation of the gallbladder is a sonographic entity in which the gallbladder lumen is entirely filled with tumefactive sludge giving the gallbladder a similar appearance to liver parenchyma. It is one of the causes of non-visualisation of the gallbladder on sonography. Pathology In the set...
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Hepatoblastoma

Hepatoblastoma is the most common primary malignant liver tumour in children under four years of age who usually present with painless abdominal mass and raised AFP. It is tumour of embryonic origin. Epidemiology Most cases are seen during the first 18 months of life and diagnosis in adulthood...
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Hepatoblastoma histological classification

Although hepatoblastomas can be histologically classified into a variety of sub types, it is important to remember that with the possible exception of small cell undifferentiated sub type, prognosis is independent of histology when adjusted for stage gender and age 1. major categories epitheli...
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Hereditary breast and ovarian cancer syndrome

Hereditary breast and ovarian cancer (HBOC) syndrome is caused by mutation to either BRCA1 or BRCA2 genes. These patients have an increased risk of breast cancer, ovarian cancer, pancreatic cancer and prostate cancer. However, these gene mutations are not the only cause of hereditary breast canc...
Article

Hereditary haemorrhagic telangiectasia

Hereditary haemorrhagic telangiectasia (HHT) is also known as Osler-Weber-Rendu syndrome. Epidemiology Worldwide prevalence ~1.5 per 100,000. Wide geographic variability with much higher incidence in certain regions, e.g. 1 in 200 in Dutch Antilles, 1 in 3500 in France. Clinical presentation ...
Article

Hereditary non-polyposis colorectal cancer

Hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome, is an inherited condition which predisposes to a host of malignancies, including colorectal carcinoma. It is considered the most frequent form of hereditary colorectal cancer. Diagnosis requires evaluation using cl...
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Hereditary pancreatitis

Hereditary pancreatitis is a rare subtype of chronic pancreatitis that has an autosomal dominant inheritance. As a congenital condition, presentation with acute pancreatitis attacks typically occurs in childhood, and features of chronic pancreatitis with parenchymal and ductal calcifications and...
Article

Heroin induced pulmonary oedema

Heroin induced pulmonary oedema is an aetiological subtype of non cardiogenic pulmonary oedema. It may be prevalent in up to 40% of patients admitted with a heroin overdose 2. It is defined by some authors as a syndrome in which a patient develops significant hypoxia (room air saturation< 90% w...
Article

Herpes oesophagitis

Herpes oesophagitis is one of the infectious oesophagitis that usually affects immunocompromised patients.  Epidemiology  It occurs as an opportunistic infection in immunocompromised patients, particularly those with AIDS. It has also been described in immunocompetent individuals 3. Pathology...
Article

Hibernoma

Hibernomas are rare benign fatty tumours that arise from the vestiges of fetal brown fat and are named “hibernoma” because of their resemblance to the brown fat in hibernating animals 1. Epidemiology Hibernomas usually occur between the ages of 20 and 40 and have a slightly increased incidence...
Article

Hidradenitis suppurativa

Hidradenitis suppurativa is an inflammatory skin disease of unknown cause. It has an autosomal dominant inheritance pattern, and androgen excess have been postulated. The disease is associated with Crohn disease and Dowling Degos disease.  Epidemiology Up to 4% of the general population are af...
Article

High-grade appendiceal mucinous neoplasms

High-grade appendiceal mucinous neoplasms (HAMN) are rare mucinous tumours of the appendix showing high-grade cytologic atypia, c.f. low-grade appendiceal mucinous neoplasms (LAMN). The distinction between both LAMN and HAMN is done on a histologic ground and those tumours basically look the sam...
Article

Hirschsprung disease

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

Histological stains

Histological stains are chemicals dyes used to treat histological specimens to make tissues more readily visible by light microscopy and demonstrate underlying characteristics of the tissue. There are many stains, some with very specific uses, whereas other (e.g. hematoxylin and eosin stain (H&E...
Article

HIV oesophagitis

HIV oesophagitis is a possible cause of odynophagia in immunosuppressed patients with HIV. Epidemiology The actual incidence and prevalence of Idiopathic oesophagitis of HIV are unknown. Most of the patients have acquired immunodeficiency syndrome (AIDS) and CD4 count <100 3. Clinical present...
Article

HIV-associated nephropathy

HIV-associated nephropathy (HIVAN) is commonly seen in patients with HIV/AIDS and leads to end stage renal disease (ESRD). The diagnosis is not imaging-based and must be confirmed by renal biopsy. Epidemiology HIVAN is seen in patients at advanced stages of HIV and AIDS, but it can also be see...
Article

HIV/AIDS

Acquired immunodeficiency syndrome (AIDS) is an immunosuppressed state, caused by infection with the human immunodeficiency virus (HIV). It is characterised by opportunistic infections, neoplasms and neurological manifestations. Epidemiology According to the United Nations programme on HIV/AID...
Article

HNF 1 alpha mutated hepatic adenoma

HNF 1 alpha mutated hepatic adenomas are a genetic and pathologic subtype of hepatic adenoma. Their appearance and prognosis is different than other subtypes. Epidemiology They are the second most common (30-35%) hepatic adenoma, after the inflammatory subtype. They occur only in female patien...
Article

Hodgkin lymphoma

Hodgkin lymphoma or Hodgkin disease (HD) is a type of lymphoma and accounts for ~1% of all cancers. HD spreads contiguously and predictably along lymphatic pathways and is curable in ~90% of cases, depending on its stage and sub-type. Epidemiology There is a bimodal distribution in the age of ...
Article

Hodgkin lymphoma (pulmonary manifestations)

Pulmonary manifestations of Hodgkin lymphoma are relatively rare, present in  5-12% of patients at the time of diagnosis. It is relatively more common with the nodular sclerosing subtype. Pulmonary involvement usually indicates stage IV disease.  Radiographic features Bilateral involvement is ...
Article

Homer Wright rosettes

Homer Wright rosettes are differentiated tumour cells grouped around a central region containing neuropil (therefore its association with tumors of neuronal origin). Pathology Examples of tumours where these can be seen include: medulloblastoma (the presence of Homer Wright rosettes in a post...
Article

Horseshoe adrenal gland

An horseshoe adrenal gland is very rare anomaly. It is also sometimes called a butterfly adrenal gland, fused adrenal gland or midline adrenal gland. It is the solitary adrenal gland that is present in the midline with the fused portion either passing between the aorta and the inferior vena cav...
Article

Horseshoe lung

Horseshoe lung is one of the rare congenital anomalies of the lung. A band of pulmonary parenchyma is formed extending between the right and left lungs. The pulmonary tissue can be seen either anterior to the aorta or posterior to the pericardium at the caudal end. Pathology Associations card...
Article

Hourglass biceps tendon

An hourglass biceps tendon refers to severe enlargement of the intra-articular portion of the biceps tendon which can entrap inside joint during flexion and become symptomatic. It can be associated with accumulation of fluid in tendon sheath within the bicipital groove.  

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