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.
Icon (Microsoft Windows 3.x). ICO is an image file format for icons on Windows. ICO file format was first introduced with Windows 1 in 1985. ICO is used to store files, programs and folders. ICO file format is very similar to .CUR files, which are used for mouse cursors. The only main difference between the two is the identification byte in the header. ICO file format is also similar to the .ICNS file format that is used for icons on Macs. An icon library can be made to package .ICO files by creating a file with an .ICL extension.