Tuesday, August 30, 2011

MRI After Arthroplasty: Comparison of MAVRIC and Conventional Fast Spin-Echo Techniques

( I am on a business trip all week.  Will try my best to keep up my daily posts.  If I miss a day, apologies in advance.)

In prior posts, I have discussed the importance of choosing the right type of MRI in order to detect underlying issues with your hips that may not have YET resulted in pain or any obvious symptoms.  While a number of surgeons order the sonogram (in my mind completely useless in this instance), the surgeons who order MRIs, use the Mars protocol.   I traveled to NYC in order to have a Mavric protocol run in order to provide optimal resolution to any underlying issues.  This is the first publication I have found on the Mavric protocol.  Here is the URL to the prior post on this subject.  In fact, the same author (Hollis Potter MD, presented on  the panel I published on earlier-What do plain radiographs, ultrasound, MRI and CT offer the Depuy hip patient (6 of 7)- is also  a co author on the article below.)

I think you can see how well the Mavric protocal  recognizes underlying pathology that the customary Mars MRI might not pick up. My only suggestion is that you speak with your surgeon about using this protocol up front in conjunction with monitoring post replacement or revision with this protocal.

This protocol selection is VERY important for patients who are interested in understanding what underlying issues might be present without out any presenting signs or symptoms.

Source

Department of Radiology and Imaging, Hospital for Special Surgery, 535 E 70th St, New York, NY 10021.

Abstract

OBJECTIVE:

The goal of this study was to evaluate the quality of images obtained with a prototype imaging technique, multiacquisition variable-resonance image combination (MAVRIC), compared with fast spin-echo (FSE) images in the evaluation of patients who have undergone hip, shoulder, or knee arthroplasty.

MATERIALS AND METHODS:

MRI with metal-artifact reduction FSE and MAVRIC sequences was performed in the care of 122 patients who had undergone 74 hip, 27 shoulder, and 21 knee arthroplasties. The FSE and MAVRIC images were subjectively graded for visualization of the synovium, prosthesis-bone interface, and hip abductors or supraspinatus tendon. The presence of synovitis, osteolysis, or supraspinatus tendon tear was recorded.

RESULTS:

Visualization of the synovium was significantly better on MAVRIC images than on FSE images of the hip (p < 0.0001), shoulder (p < 0.01), and knee (p < 0.01). Synovitis was detected only on the MAVRIC images of nine subjects (12%) who had undergone hip arthroplasty and five subjects (18%) who had undergone shoulder arthroplasty. Visualization of the periprosthetic bone was significantly better on MAVRIC images of the hip (p < 0.0001), shoulder (p < 0.0001), and knee (p < 0.01). Osteolysis was detected only on the MAVRIC images of 12 subjects (16%) who had undergone hip arthroplasty, six (22%) who had undergone shoulder arthroplasty, and five (24%) who had undergone knee arthroplasty. Visualization of the supraspinatus tendon was significantly better on MAVRIC images (p < 0.0001). Supraspinatus tendon tears in 12 subjects (44%) were detected only on MAVRIC images.

CONCLUSION:

MAVRIC complements the information on FSE images after arthroplasty and is a useful additional sequence, particularly when there is concern about synovitis, periprosthetic osteolysis, or the presence of a supraspinatus tendon tear.

4 comments:

  1. What specific MRI system is being used ( we have a 3T, GE) and what are the specific planes and MRI parameters?


    Thank you

    Kathy Green

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    1. Hi Kathy,

      In order to get this information, you would have to have an MD call Hollis Potter MD at the Hospital for Special surgery in NYC. She has the protocals.

      Hope that helps

      Regards,

      Connie

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  2. I had a Johnson & Johnson Dupay hip Implant in 2004 w/ a bad infection (Mersa) for 18 weeks of IV Antibiotics ! I have had nothing but trouble with it from the beginning ! I have been to my Orthopedic doctor that doesn't know what to do anymore ! I've had shots, pills & lots of Physical Therapy, nothing has worked ! the last shot was a month ago into the hip joint & I felt immediate relief & it lasted for 4 days, than all the pain came back & its to the point where I have to wear my Tens Unite al the time & walk w/ a cane from the time I get out of bed until I go to bed! I'm the end of my wits, I don't know where to turn anymore . I have a Pain Doctor, who has given me shots in my hip & he has also taken fluid out but the shots DON'T WORK, NOTHING DOES ANYMORE except being off of my feet, sitting & laying down ! PLEASE GIVE ME SOME SUGGESTIONS ON WHAT I SHOULD DO NOW ! THANK YOU

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    Replies
    1. I have two suggestions:

      For problems like this that are out of control, I would suggest two consults:

      1. Make an appointment to go see Dr. Josh Jacobs who is the chief of Orthopedic surgery at Rush Presby in Chicago. He does not do phone consults so you would have to see him in person with your medical records for that consult.

      2. Make an appointment with an infectious disease (ID) physician at the closest medical center near you. ID physicians specialize in these types of problems. Mersa requires and expert to treat this. Pain killers is not likely your best answer. I am not a doctor so I can't advise you but I would go down both routes.

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