Articles

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16,873 results found
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Azygos vein

The azygos vein is a unilateral vessel that ascends in the thorax to the right of the vertebral column, carrying deoxygenated blood from the posterior chest and abdominal walls. It forms part of the azygos venous system. Terminology The spelling azygous when referring to the vein is incorrect,...
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Primary cutaneous melanoma

Primary cutaneous melanoma is the most common subtype of melanoma, a malignant neoplasm that arises from melanocytes. Melanocytes predominantly occur in the basal layer of the epidermis but do occur elsewhere in the body. Primary cutaneous melanoma is by far the most common type of primary melan...
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Stove-in chest

A stove-in chest is a rare and complex type of flail chest injury where the flail segment collapses into the chest. It is usually due to severe blunt trauma to the chest wall and is rarely encountered in imaging or emergency medicine due to the high mortality at the scene. It may evolve over day...
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Peripartum/postpartum cardiomyopathy

Peripartum/postpartum cardiomyopathy is a dilated cardiomyopathy that may occur in the last trimester of pregnancy through the first several months postpartum. Epidemiology The estimated incidence in the United States ranges from one in 900 to one in 4000 live births, with an increased inciden...
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Unroofed coronary sinus

An unroofed coronary sinus, a.k.a. coronary sinus type ASD, is a rare variant of atrial septal defect (ASD). The atrial wall between the coronary sinus and left atrium is either partially or completely absent, resulting in a right-to-left shunt. It is associated with persistent left-sided super...
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Hair artifact

Hair artifact and hair-product artifacts are artifacts produced by the presence of the patient's hair, hair accessories (e.g. hair clip) and hair products (e.g. shampoo) within the field of view during acquisition of an image, which can affect all modalities to varying degrees. For example, in m...
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Excretory phase

The excretory phase also known as the urographic phase is a postcontrast injection time range in which there is an optimal enhancement of the renal collecting systems. Technique The acquisition time depends on the intravenous device (central or peripheral), the concentration of the contrast me...
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Ring of fire sign (adnexa)

The ring of fire sign, also known as ring of vascularity, signifies a hypervascular lesion with peripheral vascularity on color or pulsed Doppler examination of the adnexa due to low impedance high diastolic flow 1. This sign can be seen in: corpus luteum cyst (more commonly) ectopic pregnancy
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Omphalomesenteric fistula

Omphalomesenteric fistula occurs as a result of failure of obliteration of the omphalomesenteric duct. It is one of the congenital fistulas of the gastrointestinal tract. The treatment of choice is often a partial transumbilical resection with umbilical restitution. See also gut fistulation
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Transverse sinus

The paired left and right transverse sinuses, or lateral sinuses, are major dural venous sinuses and arise from the confluence of the superior sagittal, occipital and straight sinuses at the torcular herophili (confluence of sinuses). On each side, the transverse sinus then runs in the lateral ...
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Periodontitis

Periodontitis is an inflammatory disease affecting the supporting tissues of the teeth. It is a common cause of tooth loss, particularly in the adult population. Terminology Different forms of periodontitis are recognized. The terms 'chronic periodontitis' and 'aggressive periodontitis' have b...
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Yttrium-90 ibritumomab tiuxetan

Yttrium-90 ibritumomab tiuxetan, also known by the trade name Zevalin (Acrotech Biopharma LLC, USA), is a theranostic radiopharmaceutical approved for the treatment of patients with relapsed or refractory low grade or follicular non-Hodgkin lymphoma (NHL). More specifically, it is a radioimmunot...
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Intradural spinal lipoma

Intradural lipomas are a subset of spinal lipomas. They are typically intradural, subpial, juxtamedullary lesions 1 although they have occasionally been reported as entirely intramedullary lesions 2. Mature fatty tissue within the spinal dura can be seen in a number of entities: lipomyelo...
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Typical pulmonary carcinoid tumors

Typical pulmonary carcinoid tumors are considered the more common and more benign low grade form of peripheral pulmonary carcinoid tumors. There is little or no known association between typical carcinoid tumors and tobacco use or exposure to other carcinogens which contrasts to atypical carcino...
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De Quervain thyroiditis

De Quervain thyroiditis, or subacute granulomatous thyroiditis, is a form of self-limited subacute thyroiditis usually preceded by an upper respiratory tract viral infection such as mumps, measles, coxsackie virus, adenovirus, and influenza viruses. Epidemiology It usually affects middle-aged ...
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Colonic transit study

The colonic transit study is an older technique to estimate colonic transit time.  Terminology Various names are used for this type of study including shapes study, colon motility test, Sitz marker study and Transit-Pelletsmethod, and variations thereof.  Indications In constipation, it can ...
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Midgut volvulus

Midgut volvulus is a complication of bowel malrotation usually seen in neonates and infants. Presentation is usually with proximal small bowel obstruction and bilious vomiting. Without prompt treatment, there is a real and significant risk of small bowel ischemia, significant associated morbidit...
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Neurofibroma

Neurofibromas are benign (WHO grade 1) peripheral nerve sheath tumors that are usually solitary and sporadic. There is, however, a strong association with neurofibromatosis type 1 (NF1), particularly for the plexiform subtype.  Neurofibromas are generally divided into five morphological forms 1...
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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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Sutural diastasis

Sutural diastasis is an abnormal widening of the skull sutures. It may be physiological in a neonate during a growth spurt.  Pathology In non-traumatic scenarios accelerated growth of the sutural connective tissue without concurrent ossification is the underlying pathology.  Etiology trau...

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