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.
1,129 results
Article
Dedifferentiated chondrosarcoma
Dedifferentiated chondrosarcomas (DCS) are malignant high-grade chondrosarcomas with a poor prognosis. They have a bi-morphic histomorphology of conventional chondrosarcoma and a non-cartilaginous high-grade sarcoma.
Epidemiology
Dedifferentiated chondrosarcomas can develop in 10-15% of centra...
Article
Renal lymphoma
Renal lymphoma is usually a part component of multi-systemic lymphoma. Primary renal lymphoma is defined as lymphoma involving the kidney exclusively without any manifestation of extra-renal lymphatic disease 3-5. Typical imaging findings are multiple bilateral hypodense or infiltrative renal ma...
Article
Chondroblastoma vs clear cell chondrosarcoma
Distinguishing between a chondroblastoma and epiphyseal clear cell chondrosarcoma can be difficult and differences are listed.
Epidemiology
Both bone tumors have been reported at any age, but chondroblastomas are usually seen in the 2nd and early 3rd decade whereas clear cell chondrosarcomas h...
Article
CT abdomen-pelvis (protocol)
The CT abdomen-pelvis protocol serves as an outline for an examination of the whole abdomen including the pelvis. It is one of the most common CT protocols for any clinical questions related to the abdomen and/or in routine and emergencies. It forms also an integral part of trauma and oncologic ...
Article
Primary mediastinal large B-cell lymphoma
Primary mediastinal large B-cell lymphoma is a distinct entity, recognized in the WHO classification of lymphoma.
Epidemiology
Primary mediastinal large B-cell lymphoma accounts approximately 5% of large B-cell lymphoma, which is usually disseminated or found in the abdomen. There appears to b...
Article
Tumors of the small intestine
The small intestine is rarely the site of malignant tumors, although it accounts for ~75% of the entire length of the GI tract and more than 90% of the mucosal surface. Approximately 40 different histologic tumor types have been described.
In this article, an overview will be given of the most...
Article
HIV associated neoplasms
HIV-associated neoplasms are numerous and can be broadly divided into two groups:
AIDS-defining malignancies
associated but not AIDS defining malignancies
AIDS-defining malignancies
The development of these malignancies in HIV affected individuals generally implies progression to AIDS 4:
Ka...
Article
Bilateral testicular lesions
Bilateral testicular lesions have a relatively limited differential diagnosis.
Differential diagnosis
Neoplastic
lymphoblastic leukemia (acute or chronic)
lymphoma (non-Hodgkin's)
primary testicular lymphoma is rare but the testes are often the site of lymphoma/leukemia recurrence due to ...
Article
Skull metastases
Metastases to the skull are very common in patients with disseminated skeletal metastatic disease, although they are often asymptomatic. For a more detailed general discussion please refer to the article on skeletal metastatic disease.
Epidemiology
Skull metastases are seen in ~20% (range 15-2...
Article
Dysembryoplastic neuroepithelial tumor
Dysembryoplastic neuroepithelial tumors (DNET) are benign (WHO Grade 1) slow growing glioneuronal tumors arising from either cortical or deep grey matter. They are considered part of the heterogeneous group of tumors known as long-term epilepsy-associated tumors (LEATs).
The vast majority of DN...
Article
Hemangioblastoma (central nervous system)
Hemangioblastomas are tumors of vascular origin and occur both sporadically and in patients with von Hippel Lindau disease. They are WHO grade 1 tumors, which can occur in the central nervous system or elsewhere in the body, including kidneys, liver, and pancreas.
These tumors generally present...
Article
High-grade astrocytoma with piloid features
High-grade astrocytoma with piloid features (HGAP) is a rare tumor most commonly encountered in the posterior fossa of adults, especially those with neurofibromatosis type 1. It appears heterogeneous and has a relatively poor prognosis.
Epidemiology
Due to the small number of patients reporte...
Article
Choledochal cyst
Choledochal cysts represent congenital cystic dilatations of the biliary tree. Diagnosis relies on excluding other conditions as a cause of biliary duct dilatation, e.g. tumor, gallstone, inflammation.
Epidemiology
Choledochal cysts are rare, with an incidence of 1:100,000-150,000. Although th...
Article
Brachytherapy
Brachytherapy, also known as sealed source radiotherapy or endocurietherapy, is a form of radiotherapy where a radioactive source is placed, under the guidance of imaging, within or next to the area requiring treatment. This provides localized targeted internal radiation.
Brachytherapy has been...
Article
Soap bubble appearance (differential diagnosis)
Soap bubble appearance describes a multi-loculated bubbly appearance of lesion or structure.
A soap bubble appearance of a bone lesion refers to:
an expansile lytic lesion with internal trabeculations and preserved cortex, usually of benign nature
but may be used to describe more aggressive ...
Article
Renal osteodystrophy
Renal osteodystrophy, also known as uremic osteopathy, is a constellation of musculoskeletal abnormalities that occur in patients with chronic renal failure, due to concurrent and superimposed:
osteomalacia (adults) or rickets (children)
secondary hyperparathyroidism: abnormal calcium and phos...
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
Omental cake
Omental cake refers to infiltration of the omental fat by material of soft-tissue density. The appearances refer to the contiguous omental mass simulating the top of a cake. Masses on the peritoneal surfaces and malignant ascites may also be present.
Pathology
The most common cause is metasta...
Article
External beam radiotherapy
External beam radiotherapy (EBRT) (also known as teletherapy) is a form of ionizing radiation therapy delivered by a medical linear accelerator (or historically a cobalt-60 source) to a patient lying on a treatment bed. Megavoltage x-rays (4-25 MV) are the most commonly used. Alternative forms o...
Article
Rotational/helical/arc intensity-modulated radiation therapy
Rotational/helical/arc intensity-modulated radiation therapy (IMRT) is the most advanced form of IMRT is conceptually similar to helical or cone-beam CT 1. The radiation beam remains turned on throughout the treatment while the gantry is moved around the patient at variable speed and the multi-l...
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