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.
16,875 results found
Article
Kyphosis
Kyphosis (plural: kyphoses), much less commonly kyphus, is a term used to describe the sagittal curvature of the thoracic spine. Hyperkyphosis is when the kyphosis angle is above the normal range 5,7.
Pathology
Kyphosis increases with age, with a kyphosis angle of ~25° (range 20-29°) in adoles...
Article
Straight back syndrome
Straight back syndrome refers to decreased thoracic kyphosis ("flattening") and decreased anteroposterior thoracic diameter, such that there is compression of cardiovascular or bronchial structures.
Terminology
Straight back syndrome should not be confused with flat back syndrome, which refer...
Article
Sagittal balance
Sagittal balance, along with coronal balance, reflects the innate neutral standing position with C7 positioned over S1 1. Sagittal balance can change depending on various factors, including spinal deformities such as a loss of lumbar lordosis 1. Sagittal imbalance predicts higher rates of pain a...
Article
Sagittal vertical axis
Sagittal vertical axis/alignment (SVA) is one of the simplest and most widely used methods to assess sagittal balance 1-3.
Measurement
This measurement is performed on lateral standing full-length spine x-rays. A plumb line is drawn vertically from the middle of the C7 vertebral body 1,2 or th...
Article
Spinopelvic balance
Spinopelvic balance is an important concept in adult spinal deformities. There are numerous ways of assessing spinopelvic balance, using various bony landmarks and angles to evaluate whether or not a normal distribution of weight and stresses is present through the axial skeleton, some incorpora...
Article
Zabramski classification of cerebral cavernous malformations
The Zabramski classification of cerebral cavernomas has been proposed as a way of classifying cerebral cavernous malformations, and although not used in clinical practice it is useful in scientific publications that seek to study cavernous malformations.
The classification was proposed in 1994 ...
Article
Myxoid degeneration of a leiomyoma
Myxoid degeneration of leiomyoma is one of the rarer types of degeneration that can occur in a uterine leiomyoma. This term is related but not identical to the term myxoid uterine leiomyoma.
Epidemiology
While this type of degeneration is generally considered rare, the highest prevalence for t...
Article
Internal pudendal artery
The internal pudendal artery is a branch of the anterior division of the internal iliac artery and is the primary supply of the perineum. It is a larger vessel in males than in females and is usually the smallest branch of the anterior division of the internal iliac artery.
Summary
origin: ant...
Article
Diffuse midline glioma, H3 K27-altered
Diffuse midline glioma, H3 K27-altered is a specific entity that represents the majority of diffuse intrinsic pontine gliomas, although identical tumors are also found elsewhere in the midline (e.g. brainstem, spinal cord and thalamus) 1. They are aggressive tumors with a poor prognosis and are ...
Article
Diffuse brainstem glioma (historical)
Diffuse brainstem gliomas or diffuse intrinsic pontine gliomas was a term used to describe infiltrating astrocytomas arising in the brainstem, usually in children. It is no longer recognized as a distinct entity, removed from the 2016 update to the WHO classification of CNS tumors replaced by a ...
Article
Yasargil classification of vein of Galen aneurysmal malformations
The Yasargil classification is one of the two common systems for classifying vein of Galen malformations that is currently in use at the time of writing (mid 2024).
Classification
type I: small pure cisternal fistula between the vein of Galen (voG) and either the pericallosal arteries (anteri...
Article
Lasjaunias classification of vein of Galen aneurysmal malformations
The Lasjaunias classification, at the time of writing (mid 2024), is one of the two commonly used systems for classifying vein of Galen malformations. It relies on dividing the entity into choroidal or mural types, depending on the number and origin of feeding arteries.
Classification
choroid...
Article
Trastuzumab deruxtecan related interstitial lung disease
Trastuzumab deruxtecan related interstitial lung disease (T-Dxd ILD) is a form of drug induced lung disease which can rarely occur with the antibody-drug conjugate trastuzumab deruxtecan (T-DXd).
It can cause a fatal pneumonitis and therefore its recognition is important.
Radiographic features...
Article
Penia vs paenia (suffixes)
The suffix "-penia" as commonly seen in words such as thrombocytopenia, leucocytopenia, lymphopenia, etc. is commonly incorrectly spelled "-paenia" or even occasionally "-poenia" (incorrect derived forms using the suffix "-paenic" are also seen). This derives from the mistaken belief that the su...
Article
Posterior right subhepatic space
The posterior right subhepatic space (also known as the hepatorenal fossa or Morison pouch) separates the liver from the right kidney. It is a potential space that is not filled with any fluid in normal conditions.
Gross anatomy
The posterior right subhepatic space is a subcompartment of the s...
Article
Lambda sign (disambiguation)
There are two described lambda (λ) signs:
lambda sign (twin pregnancy)
lambda sign (sarcoidosis)
Article
Animal and animal produce inspired signs
Animal and animal produce inspired signs may sound a little silly, but the radiology literature is replete with such signs, some more fanciful than others.
Fish and marine life
cluster of black pearls sign
endosteal scalloping: medullary cavity masses, e.g. multiple myeloma
fish vertebra (al...
Article
Bird beak sign (disambiguation)
Bird beak sign is used in many contexts to denote a rapid tapering to a point, reminiscent of a bird's beak. Described bird beak signs include:
baby bird's beak sign (fetal TGA)
beak sign (arterial dissection)
beak sign (gallbladder)
beak sign (ovary)
beak sign (pyloric stenosis)
bird bea...
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 1-3.
In these cases, the pulmonary artery bifurcation and abnormal outflow tracts mimic the head of a bab...
Article
Generative adversarial network
Generative adversarial networks (GANs) are an elegant deep learning approach to generating artificial data that is indistinguishable from real data. Two neural networks are paired off against one another (adversaries). The first network generates artificial data to reproduce real data. The secon...