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.
16,876 results found
Article
Magnetically controlled growing rods
The method of magnetically controlled growing rods (MCGR) was introduced to avoid the morbidity of recurrent lengthening procedures, which are the basis of the treatment in traditional growing rods.
Procedure
As with traditional growing rods, they use spinal anchors (pedicle screws and hooks)....
Article
Volume doubling time
The volume doubling time (VDT) is an important volumetric parameter primarily used in lung cancer screening and follow-up by chest CT. Volume doubling time is defined as the time required for a growing nodule to double its volume. A longer VDT suggests a more benign course, whilst a short VDT is...
Article
Pulseless electrical activity
The diagnosis of pulseless electrical activity (PEA), also known as electromechanical dissociation (EMD), refers to the presence during cardiac arrest of electrical activity of the heart, in the absence of a ventricular tachyarrhythmia, but no measurable cardiac output 1,2. PEA is one of the non...
Article
Transfer learning
The concept of transfer learning in artificial neural networks is taking knowledge acquired from training on one particular domain and applying it in learning a separate task.
In recent years, a well-established paradigm has been to pre-train models using large-scale data (e.g., ImageNet) and t...
Article
Oropharyngeal squamous cell carcinoma
Oropharyngeal squamous cell carcinoma (OPSCC) is the most common type of head and neck cancer in the Western world 1. Typically it will be further categorized based on the specific anatomical location involved within the oropharynx, as this may affect prognosis and modality of treatment.
Epide...
Article
Rectal MRI (an approach)
Rectal MRI is a key imaging investigation in the diagnosis, staging and follow up of rectal cancer. An increase in the utility of rectal MRI as been driven by the recognition of the mesorectum as a distinct anatomic compartment containing and limiting the margins of the rectum, and forming a sur...
Article
Fetal lung interstitial tumor
Fetal lung interstitial tumor (FLIT) is a proposed designation for a rare primary lung mass detected prenatally or when the patient is up to 3 months old.
Epidemiology
Fetal lung interstitial tumors have a slight predominance in boys 1.
Clinical presentation
It can present with varying degre...
Article
B-Flow
B-Flow is a type of ultrasound imaging that allows visualization of blood flow by selectively enhancing the signal from moving blood cells while simultaneously suppressing tissue signal 1. Unlike color Doppler, it does not show flow direction or amplitude.
B-flow is used clinically to image the...
Article
Flashlight sign (B-flow)
The flashlight sign is a B-flow vascular ultrasound sign caused by wall adherent and floating thrombi and emboli in arteries, which appear as bright spots on imaging.
Radiographic features
The flashlight sign is described as a moving, very bright intraluminal focus of signal on B-flow 1.
Prac...
Article
Noise power spectrum
The noise power spectrum (NPS), also known as the power spectral density, of a signal, is the Fourier transform of the noise autocorrelation. It gives the intensity of noise as a function of spatial frequency. It is used in all the main radiological modalities, most commonly x-ray-based, i.e. ra...
Article
Coronary artery bypass graft
A coronary artery bypass graft (CABG or CAG) is placed during a surgical procedure to increase blood flow to the myocardium due to coronary stenoses, usually caused by coronary artery disease. Arteries or veins can be grafted during this procedure.
Long term outcome of coronary artery bypass gr...
Article
Heparin-induced thrombocytopenia
Heparin-induced thrombocytopenia (HIT) is a paradoxical thrombotic state resulting from an immune response to heparin, although the condition can rarely and atypically occur without heparin exposure.
Terminology
Heparin-induced thrombocytopenia and immune thrombocytopenia (ITP) are unrelated c...
Article
Stiff person syndrome
Stiff person syndrome, previously known as stiff man syndrome, is a very rare neuromuscular disease.
Epidemiology
Onset is usually between 30 and 50 years of age.
Associations
An association with autoimmune disease, in particular type 1 diabetes mellitus, and various malignancies is describe...
Article
Annulus fibrosus
The annulus fibrosus (plural: annuli fibrosi) surrounds the nucleus pulposus and together they form the intervertebral disc.
Terminology
Anulus fibrosus is the official spelling indicated by Terminologia Anatomica 6. The commonly used English word annulus is a misspelling of its Latin root ānu...
Article
Camptocormia
Camptocormia, also known as bent spine syndrome or cyphose hystérique, is a rare syndrome characterized by involuntary flexion of the thoracolumbar spine with weight-bearing which reduces when lying down, and is due to isolated atrophy of the paraspinal muscles.
Epidemiology
In a small case se...
Article
Empyema necessitans
Empyema necessitans (also sometimes spelled as empyema necessitatis) refers to the extension of an empyema out of the pleural space and into the neighboring chest wall and surrounding soft tissues.
Pathology
It may either occur due to the virulence of the organism or may be facilitated by prev...
Article
Prostate MRI (an approach)
Prostate MRI has become an increasingly frequent examination faced in daily radiological practice and is mainly conducted for the detection, active surveillance and staging of prostate cancer. This approach is an example of how to create a radiological report of a prostate MRI (usually mpMRI) wi...
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
St. Anne-Mayo grading system of astrocytomas (historical)
The St. Anne-Mayo grading system, also known as the Daumas-Duport grading system, introduced in 1988 was for a time a popular system for grading diffuse astrocytomas but has now been replaced by the WHO grading system which, however, was derived from the St Anne-Mayo system and thus shares many ...
Article
WHO grading system for diffuse astrocytomas
The WHO grading system is the most widely used system for grading diffuse astrocytomas (c.2022). It is an adaptation of the now-superseded St Anne-Mayo grading system (also known as the Daumas-Duport grading system).
Classification
Grade 1 is reserved for localized astrocytomas (see WHO class...