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.
ostium priÂ´mum an opening in the lower portion of the membrane dividing the embryonic heart into right and left sides. ostium secunÂ´dum an opening high in the septum of the embryonic heart, approximately where the foramen ovale will later appear.