Severe injury to skeletal muscle can be significant enough to raise CK-MB levels above normal, but such injury doesnât usually cause a high relative index. If your doctor suspects injury to both heart muscle and skeletal muscle, troponin is a more accurate test for identifying a heart attack.
The radial smooth muscle layer (dilator pupillae) is responsible for dilating the pupil. Source(s): http://en.wikipedia.org/wiki/Iris_%28ana...http://en.wikipedia.org/wiki/Dilator_pup...LaughingMan Â· 8 years ago.he iris is composed of two smooth muscle layers, arranged radially and circularly.
Usually a dilated pupil is caused due to a stimulus to light, wherein the pupils constrict when light brightens and dilates when light dims. Pupils dilate to allow for more light to enter the eyes, so that one is able to see objects even in a poorly lit area.