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.
Triquetra (Triqueta, Trinity Knot) The triquetra (sometimes, triqueta) is a tripartate symbol composed of three interlocked vesica pisces, marking the intersection of three circles. The triqueta symbol predates Christianity and was likely a Celtic symbol of the Goddess, and in the North, a symbol of the god Odin.