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  • Hemangioma: Another type of blood vessel malformation that can occur in the brain or liver (different from AVMs) and not connected to HHT.
  • Hematemesis: Vomiting blood.
  • Hematocrit: A measurement of blood. A normal reading would be 36% - 46%.
  • Hemiparesis: A paralysis of one side of the body usually caused by a stroke.
  • Hemiplegia: Paralysis of one side of the body. Hemiparesis is milder, where there is weakness (not paralysis) of one side of the body.
  • Hemoglobin: The substance in the blood that carries oxygen from the lungs out to various parts of the body. A normal hemoglobin count would be about 12-15.
  • Hemoptysis: Coughing up blood.
  • Hemorrhagic: Heavy bleeding.
  • Hereditary: Transmitted from generation to generation by the genes.
  • HomonymousHemianopsia: Visual impairment or blind spot of one half of one’s visual field, for example left half of each visual field in each eye (not one eye).
  • Hormone: Naturally occurring chemical substance formed by the body and carried to another area where it has a specific effect, i.e., estrogen. Hormones can also be manufactured and administered.
  • Hypoxemia: A condition in which the amount of oxygen in the blood is reduced.