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.
More than 200 results
Article
Epididymal appendix
Epididymal appendices, also known as appendix of the epididymis or appendix epididymis, are testicular appendages and are less common than appendix testes 4.
Epidemiology
Epididymal appendices are reported to occur at 12.5% (range 6-17.6%) on ultrasound and in ~33% of post-mortem studies 3,4.
...
Article
Empty notch sign (anterior cruciate ligament tear)
Empty notch sign is a direct sign of anterior cruciate ligament (ACL) tear/avulsion at its femoral attachment. It denotes a fluid signal at the expected ACL attachment site at the intercondylar notch (fossa) on axial and coronal fluid-sensitive MR images.
The proximal ACL is the second most com...
Article
Mesial temporal sclerosis
Mesial temporal sclerosis, also commonly referred to as hippocampal sclerosis, is the most common association with intractable temporal lobe epilepsy 2,3,5. It is seen in up to 65% of autopsy studies, although significantly less in imaging.
Clinical presentation
Most patients present with temp...
Article
Medial collateral ligament injury of the knee
Medial collateral ligament injuries of the knee comprise of sprains, partial and complete tears. Medial collateral ligament injuries are one of the most common ligamentous injuries of the knee.
Epidemiology
Medial collateral ligament injuries are very common in athletes 1-4 and it is likely th...
Article
Spina bifida occulta
Spina bifida occulta is the mildest form of spina bifida/spinal dysraphism and is a type of neural tube defect.
Terminology
While typically referring to asymptomatic posterior fusion defects, some authors 5 use it as a broad term that encompasses closed spinal defects such as:
diastematomyel...
Article
Adenoidal hypertrophy (children)
Adenoidal hypertrophy or enlargement in children is common and due to an increase in the size of the adenoids. For adenoidal enlargement in adults, which is much rarer and usually pathological, please see the separate article, adenoidal hypertrophy (adults).
Clinical presentation
nasal congest...
Article
Polo mint sign (venous thrombosis)
The polo mint sign is a description given to a venous thrombosis on contrast-enhanced CT imaging. When viewed in the axial plane, a thin rim of contrast persists around a central filling defect due to thrombus. This gives an appearance like that of the popular UK mint sweet, the Polo (figure 1)...
Article
Dinner fork deformity (wrist)
A dinner fork deformity, also known as a bayonet deformity, occurs as the result of a malunited distal radial fracture, usually a Colles fracture. The distal fragment is dorsally angulated, displaced and often also impacted. The term is descriptive, as the lateral view of the wrist is similar to...
Article
Coiled spring sign (bowel)
The coiled spring sign is a characteristic radiographic indicator on a contrast enema that strongly suggests the presence of intussusception. This sign results from a part of the intestine (intussusceptum) telescoping into an adjoining segment (intussuscipiens), causing obstruction and producing...
Article
Cottage loaf sign (liver)
The cottage loaf sign occurs as a result of a right-sided diaphragmatic rupture with partial herniation of the liver through the diaphragmatic defect. The herniated component is separated by a waist at the diaphragm from the larger intra-abdominal component. This shape is reminiscent of a cottag...
Article
Pneumoperitoneum
Pneumoperitoneum (aeroperitoneum is a rare synonym 12) describes gas within the peritoneal cavity, often due to critical illness. There are numerous causes and several mimics.
Pathology
The most common cause of pneumoperitoneum is the disruption of the wall of a hollow viscus. In children, the...
Article
Scaphoid impaction syndrome
Scaphoid impaction syndrome is a clinical syndrome characterized by pain or wrist tenderness caused by an impaction of the dorsal rim of the scaphoid against the dorsal lip of the radius in the setting of forced wrist hyperextension. It can occur as a consequence of repetitive stress or as a sin...
Article
Langerhans cell histiocytosis (gastrointestinal manifestations)
Gastrointestinal manifestations of Langerhans cell histiocytosis (LCH) involve the proliferation of Langerhans cells in the gastrointestinal tract 1-3. LCH usually occurs as part of multi-system disease (‘disseminated form’) in the pediatric population 4,5 but can also occur as a single-system d...
Article
Ureterocele
Ureteroceles represent abnormal congenital dilatation of the distal-most portion of the ureter. The dilated portion of the ureter may herniate into the bladder secondary to the abnormal structure of vesicoureteric junction (VUJ).
Epidemiology
A ureterocele occurs in about 1 in 5,000 to 1 in 12...
Article
Aberrant right subclavian artery
Aberrant right subclavian arteries (ARSA), also known as arteria lusoria, are among the commonest aortic arch anomalies.
Epidemiology
The estimated incidence is 0.5-2% 1.
Associations
as can be expected from the embryological development of the artery, the right recurrent laryngeal nerve is...
Article
Jones fracture
A Jones fracture is a fracture of the proximal metadiaphyseal junction of the fifth metatarsal bone that involves the 4th-5th metatarsal articulation.
Pathology
It is a transverse fracture at the base of the fifth metatarsal, 1.5 to 3 cm distal to the proximal tuberosity at the metadiaphyseal ...
Article
Calcaneal fracture
Calcaneal fractures are the most common tarsal fracture and can occur in a variety of settings.
Epidemiology
The calcaneus is the most commonly fractured tarsal bone and accounts for about 2% of all fractures 2 and ~60% of all tarsal fractures 3.
Pathology
Calcaneal fractures can be divided ...
Article
Pleural empyema
Pleural empyema refers to a collection of pus in the pleural cavity which may contain gas locules. Empyema is usually unilateral and most often occurs as a complication of pneumonia or perforated esophagus. The thickened pleura demonstrates contrast enhancement and the visceral and parietal comp...
Article
Horseshoe kidney
Horseshoe kidneys are the most common type of renal fusion anomaly. They render the kidneys susceptible to trauma and are an independent risk factor for the development of renal calculi and transitional cell carcinoma of the renal pelvis.
Epidemiology
Horseshoe kidneys are found in approximate...
Article
Sialolithiasis
Sialolithiasis refers to the formation of calculi (sialoliths) inside the ducts or parenchyma of salivary glands and most commonly occurs in the submandibular glands and their ducts.
Epidemiology
Sialolithiasis is the most common disease of salivary glands, accounting for approximately 50% of ...