CEA test: Carcinoembryonic antigen test is to detect response to therapy in cancer patients, especially colon cancer, with normal range of less than 2.5 (less than 5 in heavy smokers). Note that a positive test may not always be indicative of cancer.
Os Trigonum Syndrome. An Os Trigonum is a small, extra bone found at the back of the ankle in approximately 5-10% of people. Often it goes completely unnoticed, not causing any problems.
Aries Trigon. The Fire Signs were originally known as the Aries Trigon. The three signs belonging to this Trigon are Aries, Leo and Sagittarius. A Trigon is a group of three signs that are equidistant from one another when one measures around the circle of the Zodiac.