Category: O

  • Optic vesicle

    A hollow outgrowth from the lateral aspects of the embryonic brain. The retinae and optic nerves develop from these paired vesicles.  

  • Ocular vertigo

    Vertigo caused by disease of the eye.  

  • Objective vertigo

    Vertigo in which stationary objects appear to be moving. Vertigo where the person perceives themselves as stationary while their surroundings seem to move around them.  

  • Ovarian vein

    Either of two veins (left and right) that drain blood from the ovaries. The left ovarian vein joins the left renal vein; the right ovarian vein joins the inferior vena cava.  

  • Ovarian varicocele

    Varicosity of the veins of the ovarian or pampiniform plexus of the broad ligament.  

  • Obstructive uropathy

    Any disease that blocks the flow of urine (e.g., prostatic hyperplasia).  

  • Open tuberculosis

    Tuberculosis in which the tubercle bacilli are present in bodily secretions that leave the body. Tuberculosis that is in an active state and contagious to others.  

  • Olfactory trigone

    A small triangular eminence at the root of the olfactory peduncle and anterior to the anterior perforated space of the base of the brain.  

  • Occipital triangle of the neck

    The triangle bounded by the sternocleidomastoid, the trapezius, and the omohyoid muscles.  

  • Ooplasmic transfer

    Insertion of a donor egg’s cytoplasm, along with donor sperm, into the egg of another woman. Ooplasmic transfer is used to treat infertility and results in the development of embryos with two different sources of maternal mitochondrial DNA.