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.
16,688 results found
Article
Anomalous origin of one pulmonary artery
Anomalous origin of one pulmonary artery from the aorta (AOPA) represents a rare congenital cardiovascular anomaly. One pulmonary artery originates from the aorta and the other from the right ventricular outflow tract 1-3. It more often involves the right pulmonary artery than the left pulmonary...
Article
Scintillator (gamma camera)
The scintillator is the component of a gamma camera which receives the gamma rays emitted from a radionuclide in a nuclear medicine scan and converts it to visible light photons. It is located just behind the collimator device.
A scintillator crystal may have properties of phosphorescence, wher...
Article
D-dimer
D-dimer is a commonly tested biological marker which is produced by the enzymatic breakdown of cross-linked fibrin which forms the fibrous mesh of a blood clot. The measurement of D-dimer in the circulation acts as a marker of coagulation and fibrinolysis, which can be useful in the diagnosis of...
Article
Buphthalmos
Buphthalmos is a descriptive term which simply means an enlarged eyeball or ocular globe due to increased intraocular pressure (glaucoma), without deformation or intrinsic mass lesion.
Epidemiology
It typically manifests in infants and young children.
Pathology
In the majority of cases it in...
Article
Mononeuritis multiplex
Mononeuritis multiplex, also known as mononeuropathy multiplex, is a disorder involving two or more asymmetric peripheral nerves and is usually seen as a complication of an underlying condition 1-7. It has an acute or subacute onset and can progress to involve more nerves and develop into a poly...
Article
Skull vault hemangioma
Skull vault hemangiomas (SVH), or hemangiomas of the calvaria, are benign slow-growing vascular lesions affecting the skull diploe in any location. They have been more recently renamed osseous venous (low-flow) vascular malformations given their nonneoplastic nature, but "hemangioma" remains com...
Article
Papillary glioneuronal tumor
Papillary glioneuronal tumors are rare well circumscribed complex solid cystic supratentorial lesion with an indolent clinical course.
Epidemiology
These tumors typically are diagnosed in younger patients (median age at diagnosis 23 years) but are reported essentially in all ages 4. No sex pre...
Article
Sjögren syndrome
Sjögren syndrome, or Sjögren disease, is an autoimmune condition of the exocrine glands that produce tears and saliva.
Epidemiology
Sjögren syndrome is the second most common autoimmune disorder after rheumatoid arthritis. There is a recognized female predilection with F:M ratio of ~9:1. Patie...
Article
Peripherally inserted central catheter
Peripherally inserted central catheters (PICCs), often incorrectly tautologically termed PICC lines, are a type of central venous catheter predominantly used amongst oncology patients and those with chronic diseases (e.g. cystic fibrosis).
They offer the ability to have long-term central venous...
Article
Paraumbilical hernia
Paraumbilical hernias (alternative plural: herniae) are a type of midline ventral abdominal hernia.
Pathology
Paraumbilical hernias occur near the umbilicus when abdominal contents protrude through a defect in the linea alba and can be quite large. They are usually related to rectus abdominis ...
Article
Hepatic abscess
Hepatic abscesses, like abscesses elsewhere, are localized collections of necrotic inflammatory tissue caused by bacterial, parasitic, or fungal agents.
Epidemiology
The frequency of individual infective agents as causes of liver abscesses are intimately linked to the demographics of the affe...
Article
Umbilical venous catheters
Umbilical venous catheters (UVCs) are commonly used in neonates for vascular access and should be carefully assessed for position on all neonatal films.
Position
An umbilical venous catheter generally passes directly superiorly and remains relatively anterior in the abdomen. It passes through...
Article
Developmental anomalies of the kidney and ureter
Developmental anomalies of the kidneys and ureters are numerous and not only potentially render image interpretation confusing but also, in many instances, make the kidneys more prone to pathology:
number
renal agenesis
supernumerary kidney
fusion
horseshoe kidney: most common
cross fused ...
Article
Umbilical hernia
Umbilical hernias (alternative plural: herniae) are the most common ventral abdominal wall hernia and occur in the midline through the umbilicus.
Epidemiology
Ten times more common in females 2 and represent ~5% of all abdominal hernias 4.
Clinical presentation
Umbilical hernias may present ...
Article
Anterior suprapatellar fat pad impingement syndrome
Anterior suprapatellar (quadriceps) fat pad impingement syndrome is a controversial cause of anterior knee pain although anterior suprapatellar fat pad edema may often, and possibly more commonly, be incidental or considered an anatomical variant 1,2,11.
Clinical presentation
Patients present...
Article
Ortner syndrome
Ortner syndrome, also known as cardiovocal syndrome, is characterized by hoarse voice resulting from left recurrent laryngeal nerve palsy secondary to a cardiovascular disorder.
Pathology
Left recurrent laryngeal nerve palsy in this condition is due to traction or compression of the nerve betw...
Article
Dromedary hump
Dromedary humps are prominent focal bulges on the lateral border of the left kidney. They are normal variants of the renal contour, caused by the splenic impression onto the superolateral left kidney.
Dromedary humps are important because they may mimic a renal mass, and as such is considered a...
Article
Renal pseudotumor
Renal pseudotumors simulate a tumor on imaging but are composed of non-neoplastic tissue.
Differential diagnosis
There are many examples 1-3:
Developmental
prominent column of Bertin
persistent fetal lobulation
dromedary hump
splenorenal fusion
cross-fused renal ectopia
renal hilar lip...
Article
Hematocolpos
Hematocolpos is a term given to a blood-filled dilated vagina due to menstrual blood in the setting of an anatomical obstruction, usually an imperforate hymen. When there is concurrent uterine distention, the term hematometrocolpos is used.
Clinical presentation
Patients may present with ameno...
Article
Vaginal stenosis
Vaginal stenosis refers to a narrowing of the vagina, it can be congenital or acquired.
Clinical presentation
dyspareunia
painful pelvic examination
Complications
retrograde menstruation
Pathology
Causes
Acquired causes include:
iatrogenic
scarring from prior pelvic irradiation - brach...