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
Gull-wing appearance (phalanges)
The gull-wing appearance, also known as seagull erosions or sawtooth appearance, is classically seen in erosive osteoarthritis, typically on posteroanterior radiographs of the hands, although has also been reported in psoriatic and rheumatoid arthritis. These erosions more commonly occur at the ...
Article
Thoracic aortic stenosis (differential)
The differential for thoracic aortic stenosis includes:
atherosclerosis
aortitis (especially Takayasu arteritis)
radiotherapy
coarctation
pseudocoarctation
Williams syndrome: supravalvular aortic stenosis
congenital rubella syndrome: supravalvular aortic stenosis
Article
Right lower lobe collapse
Right lower lobe (RLL) collapse forms a triangular opacity extending from the hilum to the diaphragm. There is less overlap with the heart shadow compared to left lower lobe collapse.
Findings of lower lobe collapse can be grouped together as they are almost identical on both sides.
For a gen...
Article
Bent bone dysplasias (differential)
Bent bone dysplasias are a class of skeletal dysplasia included in a 2010 classification of genetic skeletal disorders 1:
campomelic dysplasia
Stuve-Weidemann dysplasia
kyphomelic dysplasias, a diverse class, including
congenital bowing of the long bones
cartilage-hair hypoplasia (CHH; meta...
Article
Rib notching
Rib notching refers to deformation of the superior or inferior surface of the rib. It can affect a single rib (from trauma or solitary masses e.g. schwannoma) or can affect multiple ribs.
Differential diagnosis
The differentials differ according to whether it is the superior or inferior surfac...
Article
Bronchial stenosis
Bronchial stenosis, or bronchial strictures, are descriptive terms to denote regions of focal narrowing involving the bronchi. They can arise from a wide variety of etiologies.
Pathology
Etiology
It can arise from a large range of etiological factors, which include:
tracheobronchial malignan...
Article
Calcific axillary lymphadenopathy (differential)
Calcific axillary lymphadenopathy is in general, more concerning than axillary lymphadenopathy alone and is particularly so if it contains microcalcifications. While this is concerning for malignancy, it can also occur from occasional nonmalignant causes.
Pathology
Etiology
metastatic axillar...
Article
Echogenic renal pyramids (differential)
Echogenic renal pyramids in children can be due to many different causes.
Differential diagnosis
Nephrocalcinosis
Iatrogenic (most common cause)
furosemide (frusemide)
vitamin D
steroids
Non-iatrogenic
idiopathic hypercalcemia
Williams syndrome
hyperparathyroidism
milk-alkali syndrom...
Article
Medical devices in the thorax
Medical devices in the thorax are regularly observed by radiologists when reviewing radiographs and CT scans.
Extrathoracic devices
tubing, clamps, syringes, scissors, lying on or under the patient
rubber sheets, foam mattresses, clothing, hair braids, nipple piercings, etc., may also be visi...
Article
Endometrial microcalcifications
Endometrial microcalcifications can arise from a vast range pathologies but are usually of benign in etiology. They can also occur in the endocervical region (see - endocervical microcalcifications 1)
Epidemiology
They have an increased incidence with older age, postmenopausal state, atrophic ...
Article
Leave alone lesions - skull base
Leave alone lesions of the skull base refers to incidental findings that do not require treatment nor follow-up.
This article includes findings from brain CT, HRCT of the temporal bone, and MRI studies.
Do not touch:
arrested pneumatization of the skull base - sphenoid benign fatty lesion 1
...
Article
Pancreatic calcifications
Pancreatic calcifications can arise from many etiologies.
Punctate intraductal calcifications
chronic pancreatitis
alcoholic pancreatitis (20-40%) 2
intraductal, numerous, small, irregular
preponderant cause of diffuse pancreatic intraductal calcification
gallstone pancreatitis (2%) 2
m...
Article
Synovial enhancement
Synovial enhancement is an imaging feature typically observed on MRI imaging. It can occur in various forms and can be focal or diffuse.
Pathology
inflammatory
synovitis
transient synovitis of the hip
infective synovitis
inflammatory arthritides
septic arthritis
tuberculous septic arthri...
Article
Diffuse T1 bone marrow signal loss
Diffuse T1 vertebral bone marrow signal loss is associated with replacement of fatty marrow by edema or cellular tissue.
Radiographic features
MRI
T1-weighted imaging without fat suppression is one of the most important sequences for distinguishing between normal and abnormal bone marrow. Ab...
Article
Diffuse small bowel disease
Diffuse small bowel disease may be caused by a number of conditions may be generalized multisystem disorders or conditions that effect the bowel in a global fashion:
sprue
scleroderma
Whipple's disease
amyloidosis
hypoproteinemia
giardiasis
intramural hemorrhage
radiation enteritis
smal...
Article
Mandibular lesions
Mandibular lesions are myriad and common. The presence of teeth results in lesions that are specific to the mandible (and maxilla) and a useful classification that defines them as odontogenic or non-odontogenic. While it may often not be possible to make a diagnosis on imaging alone, this classi...
Article
Right paratracheal lymphadenopathy
Right paratracheal lymphadenopathy represents pathological involvement of any of the lymph nodes in the right upper (2R) and/or lower (4R) paratracheal nodal groups 1. These nodes are often also enlarged but this is not always the case.
The commonest causes are sarcoidosis, tuberculosis and lun...
Article
Erosive arthritis (differential)
Erosive arthritis has a broad differential:
erosive osteoarthritis
clinically an acute inflammatory attacks (swelling, erythema, pain) in postmenopausal women
typically the interphalangeal joints, 1st carpometacarpal joint 6, but not the metacarpophalangeal (MCP) joints and large joints
clas...
Article
Hypervascular splenic lesions
Hypervascular splenic lesions are findings that enhance more or similarly to the background splenic parenchyma on late arterial phase, on contrast-enhanced CT or MRI.
Vascular
mycotic aneurysm
Neoplastic
splenic hemangioma 2
most common primary benign neoplasm of the spleen
second most com...
Article
Patella baja
Patella baja, also known as patella infera, is an abnormally low lying patella, which is associated with restricted range of motion, crepitations, and retropatellar pain. If longstanding, extensor dysfunction may ensue with significant morbidity.
Pathology
It is seen in a variety of clinical s...