A diagnostic MRI of the knee does not require the use of contrast dye to identify a meniscus tear, according to WebMD. Contrast dye is sometimes used during an MRI to highlight areas of infection or inflammation, locate certain types of tumors or check blood flow.
The menisci are C-shaped pieces of cartilage that act as cushion between the bones of the upper and lower leg, and are located on the inner and outer sides of the knee, states WebMD. They stabilize the knee by balancing body weight.
Tearing of a meniscus occurs during forceful rotation of the knee, squatting, heavy lifting or with age-related degenerative changes in the knee, states WebMD. Meniscus tears are classified as minor, moderate or severe, and are diagnosed using a combination of physical examination, x-rays, ultrasound imaging, MRI and diagnostic arthroscopic surgery.
Initial treatment of a torn meniscus includes rest to reduce the pressure placed upon the injured knee, ice to reduce pain and swelling, and over-the-counter pain medication. Physical therapy is beneficial to strengthen the muscles surrounding the knee and in the leg to provide added stabilization to the joint. Severe tears in the meniscus can require repair through arthroscopic surgery to remove pieces of the meniscus that are detached, or to trim and remove the torn section of cartilage, as stated by Mayo Clinic.