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 edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

10 results found

Alpha fetoprotein

Alpha fetoprotein (AFP) is an important plasma protein synthesized by the yolk sac and fetal liver. In adults its main utility is as a tumor marker, primarily for hepatocellular carcinoma or teratoma. Functionally it is the fetal homologue of albumin i.e. it acts as a major carrier protein in th...


Congestion is a pathological term referring to reduced blood flow out from tissues, which may be localized or systemic 1. Clinical presentation Congestion commonly presents with increased swelling and edema of tissues where blood flow is reduced. With prolonged congestion, the tissues may beco...


A fistula (plural: fistulae) is an abnormal connection between two epithelial surfaces such as between hollow organs, skin or vessels. Conventionally, the name of a specific fistula type is a combination of the two organs For discussions of specific fistulae please refer to individual articles....


Hematomas are the name given to localized collections of blood and they can form virtually anywhere in the body. They often form secondary to trauma or surgery but spontaneous formation is also not uncommon, especially in those with coagulation disorders or on anticoagulant therapy. Hematomas m...

Hernia (general)

Hernias (or herniae) are a common pathological entity, in which an anatomical structure passes into an abnormal location via an opening. The opening may be a normal physiological aperture (e.g. hiatus hernia: stomach passes through the diaphragmatic esophageal hiatus) or pathological. Iatrogeni...

Histology of blood vessels

Blood vessels, namely arteries and veins, are composed of endothelial cells, smooth muscle cells and extracellular matrix (including collagen and elastin). These are arranged into three concentric layers (or tunicae): intima, media and adventitia. the intima (or tunica intima) inner layer abut...

Intracranial arteries

Intracranial arteries have unique structure when compared to extracranial vessels of similar size: see general histology of blood vessels entry. Proximal larger arteries The proximal arteries, arising from the internal carotid and vertebral arteries have differing distribution of elastic fiber...


Lipohyalinosis is a disease affecting the small cerebral arteries associated with lacunar infarction and deep white matter changes related to small vessel chronic ischemia. Pathology The histopathological landmarks of lipohyalinosis are irregular fibrosis and hyaline of small cerebral arteries...

Liquefactive necrosis

Liquefactive necrosis is a form of necrosis where there is transformation of the tissue into a liquid viscous mass. Pathology In liquefactive necrosis, the affected cell is completely digested by hydrolytic enzymes leading to a soft, circumscribed lesion which can consist of fluid with remains...


Lymph (also known as lymphatic fluid) is the name given to the interstitial fluid once it has passed into the lymphatic vessels. Formation As blood passes through capillary beds a significant proportion of the plasma is filtered into the extracellular space. Most of this filtered tissue fluid ...

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.