20/01/2021

MRI Knee

For Members:

  • What is MRI?
    • Magnetic Resonance Imaging (MRI) is a type of scan that uses strong magnetic fields and radio waves to produce detailed images of the inside of the body. MRI scanner is a large tube that contains powerful magnets, you lie on a flatbed that’s moved into the scanner tube.
    • You will be provided earplugs or headphones to wear because inside the MRI scanner tube it is bit noisy. It is extremely important that you stay still during the scanning, otherwise the scan can take longer.
    • You will be provided with an intercom to communicate with your radiologist during the scanning.
    • The magnetic fields and radio waves used during MRI scan are not harmful. Multiple Researches has confirmed that MRI scans are one of the safest medical procedures available. It is a painless and safe procedure.
    • An X-ray takes pictures of your bones, whereas knee MRI lets your Physician see your bones, cartilage, tendons, ligaments, muscles, and even some blood vessels. The test can show a range of problems, including: Damaged cartilage, Torn tendons or ligaments, Bone fractures, Osteoarthritis, Infections, and Tumors etc.
    • This investigations also helps in deciding if the surgery is required for the knee or if you are healing efficiently with a treatment prescribed by your physician.
    • It can be performed with or without contrast (dye). Usually, contrast agents are used to highlight vascular structures and to help characterize inflammation and tumors. Your Physician will inform you if contrast is being used and an allergy test might be performed for contrast before the MRI.

 

  • What are the General Indications for MRI Knee?
    • Painful Swelling or clicking or Locking in the knee for more than 4-6 weeks.
    • If there is clinical suspicion of internal derangement.
    • When plain X-ray has excluded fracture, osteoarthritis and osteochondral defects.
    • Prolonged, refractory, or unexplained knee pain.
    • Patients with recurrent, residual, or new symptoms following knee surgery.
    • Detection, staging, and post-treatment evaluation of tumor of the knee.
    • Persistent knee pain/swelling and/or instability (giving way) not associated with an injury and not responding to at least 3 weeks of medical treatment.
    • Persistent knee pain/swelling and/or instability (giving way) secondary to an injury and not responding to conservative therapy when multi-view x-rays have ruled out a fracture or loose body in the knee and the clinical picture remains uncertain.
    • Persistent true locking of the knee indicative of a torn meniscus or loose body.
    • Suspected bone infection (i.e., osteomyelitis).
    • To diagnose or evaluate rheumatoid arthritis or degenerative joint disease.
  • What are the Specific Indications for MRI Knee:
    • ACUTE (FOUR TO SIX WEEKS):
    • Traumatic injury with inability to fully extend the knee, younger patient (rule out bucket-handle meniscus tear).
    • Anterior cruciate ligament tear suspected, young athlete (may have other injuries such as meniscus tear).
    • CHRONIC (TWO TO THREE MONTHS):
    • Continued knee pain with suspected surgical pathology, older patient.
    • Persistent unexplained knee pain (rule out surgical pathology).
  • When MRI Knee is NOT indicated in:
    • In the assessment of the acutely painful knee or where careful examination does not reveal signs of cruciate or collateral ligament or meniscal injury.
    • MRI does not usually provide additional information where degenerative joint disease is evident on plain X-rays.
    • Patients who have a heart pacemaker may not have an MRI scan.
    • Patients who have had metallic devices placed in their legs or back (such as pedicle screws or anterior interbody cages) can have an MRI scan, but the resolution of the scan is often severely hampered by the metal device and the spine is not well imaged.
    • Patients with severe claustrophobia may not be able to tolerate an MRI scan, although more open scanners are now available, and medical sedation is available to make the test easier to tolerate.
    • MRI scans aren’t usually recommended for pregnant women.

 

  

 For Healthcare Providers:

 

  • All MRI require pre-approval from Nextcare.
  • In rare situations (Meniscal injury, ACL injury, articular cartilage injury, collateral ligaments injury), MRI can be approved for both knees, when it is suspected during clinical examination and after excluding osteoarthritis by x-ray,
  • Always submit detailed history of the sign & symptoms with onset and duration of the disease.
  • Laboratory findings and Plain x-ray report must be submitted.
CPT Description
73721 Magnetic resonance (e.g., proton) imaging, any joint of lower extremity; without contrast material.
73722 MRI Without contrast material(s).
73723 MRA Without contrast material(s), followed by contrast material(s) and further sequences.

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