Phlebothrombosis occurs when a blood clot in a vein forms independently from the presence of inflammation of the vein (phlebitis). Thrombophlebitis is phlebitis (vein inflammation) related to a thrombus (blood clot). These conditions are usually of the superficial veins and are generally mild and uncomplicated as opposed to deep vein thromboses, which can be life-threatening.
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Phlebothrombosis Wikipedia(Text) CC BY-SA