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 continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
336 results found
Article
Bone marrow
Bone marrow is ubiquitous throughout the skeleton, primarily composed of hematopoietic cells and fat cells between bony trabeculae and fibrous retinacula. It performs numerous physiological functions and dynamically changes during normal aging and in response to stressors and pathology. Although...
Article
Immune thrombocytopenia
Immune thrombocytopenia (ITP), historically known as idiopathic thrombocytopenic purpura, is an autoimmune disorder characterized by a decrease in platelet numbers to <100 x 109/L. In most cases it is a primary condition, i.e. no underlying cause is found.
Terminology
Historically, immune thro...
Article
Dengue fever
Dengue fever is a mosquito-borne acute systemic viral infection caused by any of the four serotypes of the dengue virus.
Epidemiology
Dengue virus infections occur predominately in tropical and subtropical regions 3.
Clinical presentation
The infection can lead to a broad spectrum of sympto...
Article
Chédiak-Higashi syndrome
Chédiak-Higashi syndrome is a rare, potentially lethal, multisystemic disorder, characterized by congenital immunocompromise with susceptibility to bacterial infections, a bleeding diathesis, partial albinism affecting the skin and eyes, and gradual neurological decline 2,3.
Epidemiology
The e...
Article
Primary myelofibrosis
Primary myelofibrosis is a myeloproliferative neoplasm in which the bone marrow is replaced with collagenous connective tissue resulting in progressive fibrosis. It is characterized by:
extramedullary hematopoiesis
progressive splenomegaly
anemia
variable change in the number of granulocytes...
Article
PET-CT indications
PET-CT is a combination of cross-sectional anatomic information provided by CT and the metabolic information provided by positron emission tomography (PET).
PET is most commonly performed with 2-[F-18]fluoro-2-deoxy-D-glucose (FDG). Fluorine-18 (F-18) is an unstable radioisotope and has a half-...
Article
Labeled imaging anatomy cases
This article lists a series of labeled imaging anatomy cases by body region and modality.
Brain
CT head: non-contrast axial
CT head: non-contrast coronal
CT head: non-contrast sagittal
CT head: non-contrast axial with clinical questions
CT head: angiogram axial
CT head: angiogram coronal
...
Article
Splenic hamartoma
Splenic hamartomas are very rare lesions commonly found incidentally on imaging. They are most often solitary but may be present as multiple nodules in patients with tuberous sclerosis or Wiskott-Aldrich syndrome.
Terminology
Sclerosing angiomatoid nodular transformation (SANT) of the spleen,...
Article
Waldenström macroglobulinemia
Waldenström macroglobulinemia is a subtype of lymphoplasmacytic lymphoma (LPL), a form of B-cell lymphoma.
Terminology
Waldenström macroglobulinemia is classified as a subtype of lymphoplasmacytic lymphoma with any level of an IgM paraprotein; these two conditions are not synonymous 10.
Epide...
Article
Splenic cyst
Splenic epithelial cysts, also known as splenic epidermoid cysts or primary splenic cysts, are unilocular fluid lesions with thin and smooth walls and no enhancement. They represent ~20% of cysts found in the spleen and are usually an innocuous incidental imaging finding.
Note that most (~80%) ...
Article
Neurolymphomatosis
Neurolymphomatosis is a rare cause of neuropathy due to infiltration of the peripheral nervous system by a hematologic malignancy, in the great majority a B-cell non-Hodgkin lymphoma.
It should be differentiated from non-tumor neuropathies associated with lymphoma, such as irradiation, chemothe...
Article
Rheumatoid arthritis
Rheumatoid arthritis (RA) is a chronic autoimmune multisystemic inflammatory disease that affects many organs but predominantly attacks the synovial tissues and joints.
Epidemiology
The overall prevalence is 0.5-1% and the disease is 2-3 times more common in women 1.
Onset is generally in adu...
Article
Bing-Neel syndrome
Bing-Neel syndrome is an extremely rare neurological complication of Waldenström macroglobulinemia where there is malignant lymphocyte infiltration into the central nervous system (CNS).
Epidemiology
The exact incidence is unknown, however, in one study of patients with Waldenström macroglobul...
Article
Lymph node imaging
Lymph node imaging is a useful technique, aiding the clinician in determining whether nodes are benign or malignant. Multiple modalities are used for the assessment and characterization of lymph nodes, each with its advantages and drawbacks.
Modalities
Ultrasound
size
number
shape
contour...
Article
Hemochromatosis (CNS manifestations)
Central nervous system manifestations of hemochromatosis are uncommon and can occur in either primary or secondary hemochromatosis.
For a general discussion, and for links to other system specific manifestations, please refer to the article on hemochromatosis.
Epidemiology
Studies reporting p...
Article
Lymphatic system
The lymphatic system (also known as the lymphoid system or systema lymphoideum in Terminologia Anatomica) is the collective term given to the lymphatic vessels and lymphoid tissues in the body 1,4.
Terminology
Occasionally the lymphatic system is considered with the reticuloendothelial system ...
Article
Autoimmune encephalitis
Autoimmune encephalitis, also known as autoimmune limbic encephalitis, is an antibody-mediated brain inflammatory process, typically involving the limbic system, although any part of the brain, and central nervous system more broadly, can be involved.
Autoimmune encephalitis can be divided broa...
Article
Pyrexia of unknown origin
A pyrexia of unknown origin, commonly shortened to PUO, and also known as a fever of unknown origin (FUO), was originally defined in 1961 as the condition in which the core body temperature is >38.3oC for a period of three weeks or more, with no diagnosis reached after one week of inpatient inve...
Article
Infectious mononucleosis
Infectious mononucleosis (also known as glandular fever) is the term for infection with Epstein-Barr virus (EBV). The infection classically occurs in teenagers and young adults, hence its popular name kissing disease. It is usually a clinical diagnosis, with confirmation by serum testing, but ma...
Article
Orbital lymphoma
Primary lymphoma of the orbit is one of the most common orbital tumors and accounts for as much as half of all orbital malignancies. It is a B-cell non-Hodgkin lymphoma, and in most cases arises from mucosa-associated lymphoid tissue (MALT).
Epidemiology
Orbital lymphomas account for only 2% o...