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.
16,873 results found
Article
Glomangioma
Glomangiomas, also known as glomus tumors, are benign vascular tumors typically seen at the distal extremities. On imaging, they characteristically present as small hypervascular nodules under the fingernail.
Terminology
These tumors should not be confused with paragangliomas, which were form...
Article
Calponin
Calponin is an actin-binding protein regulating actin/myosin interaction in smooth muscle and non-muscle cells 1,2. It inhibits actin-activated myosin ATPase and stabilizes the actin cytoskeleton. It also serves as a target in immunohistochemistry where it can be used for the identification of m...
Article
Cervical cancer (staging)
Staging of cervical cancer can either be based on the TNM or FIGO system.
Classification
Revised FIGO staging of cervical carcinoma (2018)
FIGO no longer includes stage 0 (Tis)
I: confined to cervix uteri (extension to the corpus should be disregarded)
IA: invasive carcinoma only diagnosed ...
Article
Baby bird’s beak sign
The baby bird's beak sign is an antenatal ultrasound appearance formed by the pulmonary artery abnormally arising from the left ventricle in fetuses with transposition of the great arteries.
In these cases, the pulmonary artery bifurcation and abnormal outflow tracts mimic the head of a baby bi...
Article
Choledocholithiasis
Choledocholithiasis denotes the presence of gallstones within the bile ducts (including the common hepatic duct/common bile duct).
Epidemiology
Choledocholithiasis is relatively common, seen in up to 20% of patients undergoing cholecystectomy for gallstone-related complaints 2.
Clinical prese...
Article
Pineoblastoma
Pineoblastomas are tumors that are best thought of as small round blue cell tumors located in the pineal region and thus, they closely resemble (both on imaging and on histology) medulloblastomas and retinoblastomas. They are the most aggressive and highest grade tumor among pineal parenchymal t...
Article
Septic arthritis
Septic arthritis is a destructive arthropathy caused by an intra-articular infection which usually manifests as severe symptoms such as pain and decreased range of motion. This condition requires prompt treatment aiming to avoid permanent damage to the joint, which may result in chronic deformit...
Article
Brown tumor
A brown tumor, also known as osteitis fibrosa cystica and rarely as osteoclastoma, is one of the manifestations of hyperparathyroidism. It represents a reparative cellular process, rather than a neoplastic process. Histologically brown tumors are identical to giant cell tumors (both are osteocla...
Article
Hand (bilateral PA view)
The bilateral PA view is merely a single film that includes both hands, side by side. Although convenient, research in 2023 showed that the distortion due to divergent rays when imaging bilaterally can impact diagnosis and x-raying the hands individually is preferred at a minimal dose increase 1...
Article
Dysmyelinating disorders
Dysmyelinating disorders are a subset of white matter disorders characterized by abnormal myelination 1. They include numerous inherited conditions that are characterized by a defective structure and function of the myelin sheath 2.
Terminology
Dysmyelinating disorders are often thought of be...
Article
Papez circuit
The Papez circuit is a fundamental component of the limbic system. It is closed neural circuitry that starts and ends in the hippocampus. It is also known as the medial limbic circuit.
Gross anatomy
The Papez circuit involves different structures of the brain including 2:
hippocampus and adja...
Article
Rib fractures
Rib fractures are a common consequence of trauma and can cause life-threatening complications.
Epidemiology
Associations
Rib fractures are often associated with other injuries and the greater the number of rib fractures the more likely are associated injuries 1,3:
brachial plexus or subclavi...
Article
Strain elastography
Strain elastography (also known as tissue strain elastography/static elastography/compression elastography) is a developing form of ultrasound that assesses tissues' macroscopic structure through the strain modulus. This is different from normal B-mode grayscale ultrasound which characterizes a ...
Article
Air gap technique (general radiography)
The utilization of the air gap technique in general radiography is limited due to the need for equipment facilitation to create the air gap when it is not inherent in the standard technique.
Horizontal-beam lateral hip
There are many different methods of performing the horizontal beam lateral ...
Article
AAST spleen injury scale
The American Association for the Surgery of Trauma (AAST) splenic injury scale, revised in 2018, is the most widely used grading system for splenic trauma.
The 2018 update incorporates "vascular injury" (i.e. pseudoaneurysm, arteriovenous fistula) into the imaging criteria for visceral injury 4...
Article
Tesla (SI unit)
The tesla (symbol T) is the derived SI unit of magnetic flux density, which represents the strength of a magnetic field. One tesla represents one weber per square meter. The equivalent, and superseded, cgs unit is the gauss (G); one tesla equals exactly 10,000 gauss.
Medical magnetic resonance ...
Article
Congenital infiltrating lipomatosis of the face
Congenital infiltrating lipomatosis of the face is a very rare congenital, non-hereditary disease manifesting with prominent unilateral facial overgrowth and deformity.
Clinical presentation
Facial asymmetry is always noted at birth. Other findings on the affected side include:
unilateral ske...
Article
Hysterosalpingogram
A hysterosalpingogram (HSG) is a fluoroscopic examination of the uterus and the fallopian tubes, most commonly used in the investigation of infertility or recurrent spontaneous abortions.
Indications
infertility: to assess uterine morphology and tubal patency
Contraindications
pregnancy
act...
Article
Adult fibrosarcoma
Adult fibrosarcomas are rare, malignant and highly aggressive fibroblastic soft tissue tumors. They constitute a diagnosis of exclusion.
Epidemiology
Adult fibrosarcomas by definition are rare and make up around 1% of soft tissue sarcomas. They are mostly seen in middle-aged people within the ...
Article
Rectal cancer response assessment
Assessment of rectal cancer response to therapy, which may be chemotherapy, radiotherapy, or a combination, relies on the synthesis of clinical, endoscopic and radiologic evaluation.
The purpose of neoadjuvant therapy is to downstage the tumor, to facilitate surgical resection, and reduce loca...