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.
16,916 results
Article
Thyroid gland
The thyroid gland is a single midline endocrine organ in the anterior neck responsible for thyroid hormone production which lies in the visceral space completely enveloped by pretracheal fascia (middle layer of the deep cervical fascia).
Gross anatomy
The thyroid extends from C5 to T1 and lies...
Article
Congenital megaureter
A congenital (primary) megaureter encompasses causes of an enlarged ureter which are intrinsic to the ureter, rather than as a result of a more distal abnormality; e.g. bladder, urethra (see secondary megaureter). It includes:
obstructed primary megaureter
refluxing primary megaureter
althoug...
Article
Trapezius muscle
The trapezius muscle is a large, broad superficial muscle of the posterior neck and back. It gains its name from its diamond shape. Along with sternocleidomastoid muscle, it is invested by the superficial layer of the deep cervical fascia, which splits around it.
Summary
origin: superior nuch...
Article
Ciliated hepatic foregut cyst
Ciliated hepatic foregut cysts are a very rare type of hepatic cyst, with non-specific radiological features. They are usually benign, but rare cases of malignant degeneration (to squamous cell carcinoma) have also been reported.
Epidemiology
They are more often seen in adults, although a few...
Article
Focal cemento-osseous dysplasia
Focal cemento-osseous dysplasia is a subtype of cemento-osseous dysplasia. It occurs in the posterior aspect of the jaw, namely in the mandibular molar region, away from the periapical aspect of the teeth.
Epidemiology
Most common in the 4th and 5th decades of life. Strong female predilection ...
Article
Pinned images
Pinned images are added to a file and can be used to add a case to an article. This is useful when you come across a particularly good example of a condition, an unusual feature or a rare condition that is under-represented.
To pin an image, go to the three dots at the top right of the image an...
Article
Pectoralis minor muscle
The pectoralis minor muscle is a muscle of the pectoral region lying deep to and completely covered by the pectoralis major muscle.
It is an important anatomical landmark in two senses:
it arbitrarily divides the axillary artery into 3 parts
it arbitrarily divides the axillary lymph nodes in...
Article
Subclavius muscle
The subclavius muscle is a small triangular muscle of the pectoral region which depresses the shoulder.
Summary
origin: 1st costochondral joint
insertion: subclavian groove on the inferior aspect of the middle third of the clavicle
innervation: nerve to subclavius (from nerve roots C5-C6)
a...
Article
Pectoralis major muscle
The pectoralis major muscle is a large fan-shaped muscle of the pectoral region, overlying the anterior chest wall but often considered an upper limb muscle due to its function.
Summary
origin: medial clavicle, sternum, costal cartilages, and external oblique aponeurosis
insertion: lateral l...
Article
Line focus principle
The line focus principle in radiography explains the relationship between the actual focal spot on the anode surface and the effective focal spot size.
Basic concept
The focal spot is the area of the target upon which the electron beam strikes. The energy of the electrons in the electron beam ...
Article
Crossed renal ectopia
Crossed renal ectopia is said to be present when the kidney is seen in the opposite retroperitoneal space. It is more common for the left kidney to be ectopically located on the right side. More than 85% of these get fused resulting in crossed fused renal ectopia. Less than 15% cases are non-fus...
Article
Q-Factor
The Q-factor is the ratio of the center frequency (f0) to the bandwidth.
High Q-factor transducer indicates a narrow bandwidth and a long spatial pulse length with low damping and narrow bandwidth. This commonly used in doppler ultrasound where a narrow bandwidth is needed to accurately quantif...
Article
Binning
Binning is a term which at its most abstract implies combining and organizing various elements of data, but in terms of radiology usually implies a technique by which signals arriving from adjacent physical elements of an electronic detector are combined to produce a larger pixel/voxel.
This pr...
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
Chronic exertional compartment syndrome
Chronic exertional compartment syndrome (CECS), previously known as anterior tibial syndrome, is a type of compartment syndrome that is brought on by exercise.
Epidemiology
The exact prevalence is not known since sufferers may modify the way they exercise and therefore never present. CECS can ...
Article
Zenker diverticulum
Zenker diverticulum, also known as a pharyngeal pouch, is a posterior outpouching of the hypopharynx, just proximal to the upper esophageal sphincter through a weakness in the muscle layer called the Killian dehiscence.
Epidemiology
More than 50% of the affected patients present in 60-80 years...
Article
MRI of the wrist (an approach)
MRI of the wrist is a fairly frequent examination in musculoskeletal radiology practice and not quite as common in general radiological practice. This approach is an example of how to create a radiological report of an MRI of the wrist with coverage of the most common anatomical sites of possibl...
Article
Lunotriquetral ligament
The lunotriquetral ligament joins the lunate and triquetrum of the carpals.
Gross anatomy
The lunotriquetral ligament arises from the volar aspect of the distal lunate and triangular fibrocartilage to distally attach to the medial margin of the hamate. Similar to the scapholunate ligament, it ...
Article
Radiocarpal joint
The radiocarpal joint is an articulation between the distal radius and the proximal carpal row of the wrist. It is a major synovial joint of the wrist and is an example of a condyloid joint.
Gross anatomy
Location
The joint occurs proximally between the concave surface of the distal end of t...
Article
Dorsal intercarpal ligament
The dorsal intercarpal ligament is one of the extrinsic wrist ligaments.
Gross anatomy
The dorsal intercarpal ligament has a horizontal orientation, however, together with the dorsal radiotriquetral ligament, it is said to have a zig-zag configuration.
It runs from the dorsal tubercle of the ...