This project aims to provide routine MRI of subjects with total joint replacements by reducing the severe image artifacts near metal, while offering highly efficient patient-specific scans that can detect bone loss, infection, and temparature changes near the implant in clinically feasible scan times. Relevance: Total joint replacements are one of the most successful orthopedic procedures, used annually to reduce pain from joint diseases in about one million patients in the United States (a number projected to double by 2030). However, about 10% of joint replacements fail in 5-10 years due to bone loss (osteolysis), infection, or other complications, often leading to revision surgery. Accurate, early non-invasive assessment of complications remains limited, but would offer earlier and less invasive treatments, reduce unnecessary surgery, or allow better surgical planning. Approach: We have previously developed novel MRI techniques that allow visualization of pathology adjacent to metallic implants, and together with other groups have successfully applied them to imaging of patients with devices including joint replacements and spinal fixation hardware. However these methods remain slow, have limited spatial resolution, and are challenging to use routinely. Therefore our aims are (1) to provide patient- specific scans that increase imaging efficiency for different types of implant, (2) to further accelerate scans with advanced sampling and image reconstruction, (3) to offer non-invasive temperature measurement near implants during MRI and (4) to validate all methods at 3T in patients with total joint replacements to measure imaging improvements as well as to assess diagnostic accuracy and the role of our new MRI methods in patient evaluation prior to revision surgery. Summary:
We aim to offer comprehensive MRI techniques for patients with joint replacements with compa- rable scan times and resolution to conventional MRI, but with complete correction of image artifacts. These techniques will allow routine, non-invasive evaluation for earlier and more accurate detection and treatment of complications in these patients, as well as numerous other applications of MRI near metal implants.
There is a growing need for accurate diagnosis of complications surrounding joint arthroplasty, where MRI would provide excellent contrast if not for the fact that the presence of metal severely degrades images. Building on recent ideas, we propose to develop practical methods for routine clinical imaging of patients with metal implants by increasing speed as well as offering image contrast that shows infection and other complications near the metal devices. Ultimately these methods will be tested and offered for widespread use to enable earlier and better treatment of complications resulting from arthroplasty, as well as for better understanding of the implications of different devices.
|Gutierrez, Luis B; Do, Bao H; Gold, Garry E et al. (2015) MR imaging near metallic implants using MAVRIC SL: initial clinical experience at 3T. Acad Radiol 22:370-9|