Experts recommend MSK Ultrasound First before MRI
In 2013, a consensus panel of experts determined that ultrasound should be the primary means of imaging evaluation of the rotator cuff.
55 year old union carpenter. History of chronic overhead labor and a recent pop in the shoulder followed by weakness and pain. The patient’s insurance initially denied the physician’s request for MRI and the patient had an ultrasound showing a full thickness retracted supraspinatus tear.
The patient was refered to surgery and the surgeon obtained preop MRI for evaluation of the shoulder.
The insurance company refused to pay for the MRI. Ultrasound shows the tear in higher resolution than the MRI. The MRI cost on around $600. The msk ultrasound was less that one quarter of that cost. MRI was subsequently obtained by the orthopedic surgeon to look at the labrum.
Rotator Cuff Ultrasound is the Obvious Winner
Even to the untrained eye, seeing comparison images between a 1.5 tesla MRI versus a high resolution MSK ultrasound shows obvious differences. Ultrasound has much higher resolution. The contrast is also much better.
Actual rotator cuff tear
Look at the obvious rotator cuff tear of this patient compared to the opposite shoulder which is normal.
Rotator Cuff Ultrasound has many advantages over MRI that increases confidence.
Rotator cuff tears can be confirmed on musculoskeletal ultrasound with multiple techniques that include dynamic imaging, compression imaging, acoustic enhancement, measurement of blood flow, more accurate measurements, comparison with the opposite shoulder, and with basic better resolution.
Ultrasound is Easier on the patient
An ultrasound of the shoulder performed by an expert can take between 8 and 20 minutes depending on the complexity of the findings. A normal shoulder would be closer to 8 minutes. MRI of the shoulder takes at least 20-30 minutes of time scanning (patient laying still on the table). Plus the time to intake the patient, screen for MRI contraindications, change the patient so that no metal is present and then put them on the table and place the coil.
Additional disadvantages of MRI
- Claustrophobic. Even if done in open MRI, patients can still struggle. Open MRI is also less powerful that a closed MRI.
- Metal: If a patient has a BB, shrapnel, foreign body they may not be safe to get an MRI. This is especially true for iron near critical structures such as veins or arteries or near skin. Some dental implants can also burn the soft tissue
- Medical device: VP shunts, cardiac pacing devices, nerve stimulators, heart valves, have limitations for MRI. Most are MRI conditional or contraindicated which means they can’t be scanned in just any MRI due to strength or field shape. All require research by the doctor and the MRI facility to approve which can delay imaging. There are safe devices or devices that can go to specific machines so check with your radiologist.
- Pain/discomfort: patients must lay still in on the their back or side or stomach for 30 minutes on average. Patients with pain due to injuries, especially back pain struggle. Patients with breathing problems also have to hold their breath for certain sequences and heavy breathing interferes with the test
- Tremors/restless leg syndrome: Motion may make the MRI not readable.
- Cost an MRI can cost between 300-1500 dollars depending on where and what it is done for. Sometimes more expensive. An ultrasound is under $200 for most things.