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.
1,114 results found
Article
Duodenal filling defects
Duodenal filling defects may be caused by a wide variety of duodenal pathology which may be divided by their location and pathological process.
Extrinsic
gallbladder impression
common bile duct impression
gas-filled diverticulum
Intrinsic
Note: please refer to duodenal mucosal nodular fill...
Article
Well-defined breast cancers (differential)
Certain well-defined breast cancers tend to lack the characteristic spiculation and can give false reassurance of more benign entities on both ultrasound and mammography. These include:
certain high grade invasive ductal carcinomas: not enough time for a desmoplastic reaction to form spiculatio...
Article
Yttrium-90
Yttrium-90 (90Y) is a radioisotope derived from the decay of 90Sr.
Yttrium-90 decays due to the emission of β- particles, with a half-life of 2.67 days 5. It has no gamma energy emission, but may be imaged through the use of bremsstrahlung interactions with planar or SPECT imaging. A small amou...
Article
Kaposiform hemangioendothelioma
Kaposiform hemangioendotheliomas are rare, locally invasive vascular tumors that often present in infancy, most commonly as an enlarging cutaneous mass 1,2. They are currently classified as distinct from tufted angiomas in the ISSVA classification of vascular anomalies. However, some consider it...
Article
Benign and malignant characteristics of breast lesions at ultrasound
Benign and malignant characteristics of breast lesions at ultrasound allow the classification as either malignant, intermediate or benign based on work published by Stavros et al. in 1995.
Radiographic features
Ultrasound
Malignant characteristics (with positive predictive values)
sonog...
Article
Ischemic colitis
Ischemic colitis refers to inflammation of the colon secondary to vascular insufficiency and ischemia. It is sometimes considered under the same spectrum as intestinal ischemia. The severity and consequences of the disease are highly variable.
Epidemiology
Ischemic bowel is typically a disease...
Article
Chordoma
Chordomas are uncommon malignant tumors of the axial skeleton that account for 1% of intracranial tumors and 4% of all primary bone tumors.
They originate from embryonic remnants of the primitive notochord (earliest fetal axial skeleton, extending from the Rathke's pouch to the tip of the cocc...
Article
Neuroblastoma
Neuroblastomas are tumors of neuroblastic origin. Although they may occur anywhere along the sympathetic chain, the vast majority arise from the adrenal gland.
They represent the most common extracranial solid childhood malignancy and are the third commonest childhood tumor after leukemia and b...
Article
Meningeal hemangiopericytoma (historical)
Hemangiopericytomas of the meninges are rare tumors of the meninges, now considered to be an aggressive form of solitary fibrous tumors of the dura. They often present as large and locally aggressive dural masses, frequently extending through the skull vault. They are difficult to distinguish on...
Article
Malignant transformation
Malignant transformation is the term given to the process whereby either normal, metaplastic, or benign neoplastic tissue, becomes a cancer. The process usually occurs in a series of steps and the affected tissue gradually accumulates the genetic mutations that express a malignant phenotype. The...
Article
Adrenal metastasis
Adrenal metastases are the most common malignant lesions involving the adrenal gland. Metastases are usually bilateral but may also be unilateral. Unilateral involvement is more prevalent on the left side (ratio of 1.5:1).
Epidemiology
They are present at autopsy in up to 27% of patients with ...
Article
Ovarian-Adnexal Reporting and Data System Ultrasound (O-RADS US)
The Ovarian-Adnexal Reporting and Data System Ultrasound (O-RADS US) forms the ultrasound component of the Ovarian-Adnexal Reporting and Data System (O-RADS). This system aims to ensure that there are uniform unambiguous sonographic evaluations of ovarian or other adnexal lesions, accurately ass...
Article
Neoplasm
Neoplasms, also known as tumors, are pathological masses, caused by cells abnormally proliferating and/or not appropriately dying. Neoplasms may be either benign or malignant. Malignant neoplasms are synonymous with cancers.
Benign neoplasms
clear origin (unless very large)
slow growth
usua...
Article
Basal cell carcinoma
A basal cell carcinoma (BCC) is one of the commonest non-melanocytic types of skin cancer.
Epidemiology
Typically present in elderly fair-skinned patients in the 7th to 8th decades of life. There may be an increased male predilection.
Associations
Multiple basal cell carcinomas may be prese...
Article
Retiform hemangioendothelioma
Retiform hemangioendotheliomas or hobnail hemangioendotheliomas are intermediate locally aggressive and rarely metastasizing vascular neoplasms with a distinctive hobnail endothelial cell morphology.
Epidemiology
Retiform hemangioendotheliomas are rare with <100 cases reported in the literatur...
Article
Superscan
A superscan is an imaging appearance on a Tc-99m diphosphonate bone scan which occurs as a result of a high ratio of bone to soft tissue tracer accumulation. Intense osteoblastic activity in the bones causes diminished renal and background soft tissue uptake.
Pathology
Etiology
This appearanc...
Article
Kimura disease
Kimura disease, also known historically as eosinophilic hyperplastic lymphogranuloma, is a rare benign inflammatory disease that characteristically manifests as enlargement of cervical lymph nodes and salivary glands.
Epidemiology
Kimura disease typically affects males (80%) between 20-40 year...
Article
Lung cancer (staging - IASLC 7th edition) (historical)
The IASLC (International Association for the Study of Lung Cancer) 7th edition lung cancer staging system was proposed in 2010 and has now been updated and superseded by the 8th edition, published in 2016.
Small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) used to be staged di...
Article
Primary cutaneous melanoma
Primary cutaneous melanoma is the most common subtype of melanoma, a malignant neoplasm that arises from melanocytes. Melanocytes predominantly occur in the basal layer of the epidermis but do occur elsewhere in the body. Primary cutaneous melanoma is by far the most common type of primary melan...
Article
Yttrium-90 ibritumomab tiuxetan
Yttrium-90 ibritumomab tiuxetan, also known by the trade name Zevalin (Acrotech Biopharma LLC, USA), is a theranostic radiopharmaceutical approved for the treatment of patients with relapsed or refractory low grade or follicular non-Hodgkin lymphoma (NHL). More specifically, it is a radioimmunot...