Articles

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16,825 results found
Article

Vertebra

The vertebra (plural: vertebrae) is the fundamental segmental unit of the vertebral column (also known as the spine). Gross anatomy Vertebrae, apart from those that are atypical, have a similar basic structure which can be described as an anterior vertebral body and a posterior neural (or vert...
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Rhodium (Rh)

Rhodium (chemical symbol, Rh) is a precious metal of atomic number 45 and atomic weight 102.90549 1. It belongs to Groups 8-10 and Periods 5 and 6 of the periodic table 1. Use in medical imaging Rhodium is important in medical imaging primarily for its use as a target (anode) and/or filter in ...
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Barbell sign (progressive multifocal leukoencephalopathy)

The barbell sign is a radiological sign present in progressive multifocal leukoencephalopathy (PML) on MRI brain. This describes confluent T2/FLAIR parieto-occipital abnormalities with a thin continuation of signal abnormality across the splenium 1,2. Given the lack of mass effect typically exh...
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Ball of wool sign (hydatid cyst)

The ball of wool sign, also referred to as the yarn sign or congealed water lily sign, is an ultrasound appearance, representing degeneration of hydatid cysts (WHO class CE 4). The inner side of the cyst detaches from the cyst wall and folds on itself, causing a change from anechoic (fluid) to a...
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Shiny corner sign (ankylosing spondylitis)

The shiny corner sign is a spinal finding in ankylosing spondylitis, representing reactive sclerosis secondary to inflammatory erosions at the superior and inferior endplates (corners on lateral radiograph) of the vertebral bodies, which are known as Romanus lesions. Eventually, the vertebral bo...
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EULAR-OMERACT ultrasound scoring system for synovitis in rheumatoid arthritis (RA)

The EULAR-OMERACT ultrasound scoring system for synovitis in rheumatoid arthritis (RA) is a standardized method for assessing synovial inflammation using ultrasound imaging. This scoring system was developed collaboratively by the European League Against Rheumatism (EULAR) and the Outcome Measu...
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Para-articular chondroma

Para-articular chondromas, also known as intracapsular chondromas, are one of the three variants of extraskeletal chondromas, the other two being synovial chondromatosis and soft tissue chondroma. These tumors arise from chondroid metaplasia of the joint capsule 1. Epidemiology These tumors ar...
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Rim rent tear of rotator cuff

A rim rent tear of the rotator cuff, also known as partial articular surface tendon avulsion, is a specific subtype of partial-thickness rotator cuff tear that involves the articular surface footprint at the site of tendon attachment into the greater tubercle of the humerus 2. Such small tears...
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Usual ductal hyperplasia

Usual ductal hyperplasia, also known as epithelial hyperplasia, is a benign proliferation of normal cells in breast ducts and lobules. Epidemiology The mean age of patients with epithelial hyperplasia is 54 years 1. Clinical presentation Epithelial hyperplasia is usually asymptomatic and fou...
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Cerebellar bottom-of-fissure dysplasia

Cerebellar bottom-of-fissure dysplasia is a rare grey matter dysplasia occurring in cerebellar hemispheres. Terminology Cerebellar bottom-of-fissure dysplasia is so named because it exclusively involves the cerebellar grey matter at the depths of the cerebellar fissures. Epidemiology To date...
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Chronic hypersensitivity pneumonitis (historical)

Chronic hypersensitivity pneumonitis is a legacy term not recommended in the most recent guidelines (c. 2020) 12. In chronic hypersensitivity pneumonitis, there is radiological evidence of fibrosis which represents the end-stage of repeated or persistent pneumonitis 7. Most of the manifestations...
Article

Hypodontia

Hypodontia, also known as oligodontia or adontia, refers to the developmental failure of one or more teeth, excluding the third molars. Terminology The phenomenon of non-development of teeth has been described using several terms including 'hypodontia', 'oligodontia' and 'adontia'. The descrip...
Article

Upper lobe bronchiectasis

Distribution of bronchiectasis can help in narrowing the differential diagnosis. Upper lobe bronchiectasis is typically seen in: cystic fibrosis tuberculosis Rarely it may be seen with non-tuberculous mycobacterial infection (e.g. MAC infection 2). Traction bronchiectasis in the upper lobes c...
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Bracket sign (disambiguation)

A bracket sign has been named in multiple contexts: bracket sign in CT brain of calcification in tubulonodular pericallosal lipoma bracket sign in MRI brain of of the superior most extent of the pars marginalis of the cingulate sulcus
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Radial bands sign (tuberous sclerosis)

The radial bands sign, also known as radial migration bands, refers to linear bands seen on MRI, radiating from the periventricular white matter to the subcortical region, thought to be specific for tuberous sclerosis 1,2. Pathology The exact pathogenesis of radial bands is uncertain, but they...
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Lymphomatoid granulomatosis

Lymphomatoid granulomatosis, also known as angiocentric lymphoma or angiocentric immunoproliferative lesion, is a rare type of non-Hodgkin lymphoma associated with Epstein-Barr virus infection.  Pathology There is a recognized association with antecedent infection with the Epstein-Barr virus (...
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Lymphomatoid granulomatosis (pulmonary manifestations)

Pulmonary manifestations of lymphomatoid granulomatosis are important since the lung is one of the most frequent sites of involvement in lymphomatoid granulomatosis. It falls under the group of pulmonary angiitis and granulomatosis. Pathology Some consider the condition to be midway between ov...
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Medical abbreviations and acronyms (L)

This article contains a list of commonly used medical abbreviations and acronyms that start with the letter L and may be encountered in medicine and radiology (please keep the main list and any sublists in alphabetic order). A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R ...
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Medical abbreviations and acronyms (R)

This article contains a list of commonly used medical abbreviations and acronyms that start with the letter R and may be encountered in medicine and radiology (please keep the main list and any sublists in alphabetic order). A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R ...
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Iliohypogastric nerve

The iliohypogastric nerve arises from the anterior ramus of the L1 nerve root of the lumbar plexus along with the ilioinguinal nerve. It is a sensory nerve that provides lateral and anterior cutaneous branches supplying the posterolateral gluteal skin and skin in the pubic region. Gross anatomy...

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