Articles

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More than 200 results
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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 ...
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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
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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...
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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...
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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...
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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...
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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...
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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...
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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...
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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 ...
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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 ...
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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...
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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...
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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...
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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...
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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...
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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...
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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...
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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...
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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...