Images Dated 2nd July 2002

False-colour SEM of a human blood clot

False-colour scanning electron micrograph (SEM) of a human blood clot (thrombus), showing strands of fibrin around red blood cells. Blood clots or thrombi form inside blood vessels when there is a defect in the normal haemostatic mechanism. A thrombus composed of red blood cells trapped in a network of fibrin stands is typically formed in areas of stasis (no blood flow) and is known as a coagulation thrombus. Such thrombi are commonly formed in the legs of patients confined to bed in hospital. They may be treated with drugs that interfere with fibrin formation (anticoagulants) or with fibrinolytic drugs that digest fibrin. Mag: x3, 000 at 35mm, x6, 000 at 6x7cm size. RBCs coloured light blue, fibrin pink

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