MRI compatibility of silver based wound dressings
As silver dressings gain more widespread use, it is more likely that patients with silver-based dressings will also undergo magnetic resonance imaging (MRI).
In current practice, these dressings are removed prior to imaging due to concerns over heating and image distortion. As dressing changes can be painful, the need to remove dressings simply for MRI may increase pain and contribute to opioid dependency. To examine the need for dressing removal, American Society for Testing and Materials International standards for assessing device deflection and torque were performed on 5 silver containing and 3 non-silver control dressings.
Magnetically induced heating and image distortion were examined in a porcine hind limb wound dressed with control and test dressings. The limb was scanned in a clinical high field 3T MRI scanner using a series of standard MRI sequences (Survey, T 1 -weighted SE, T 1 -weighted IR TSE, T 2 -weighted TSE, DUAL TSE, and FLAIR). Deflection and torsion were not detected in control or silver-based dressings.
For all combinations of dressings and MRI scans, average heating was between 0–۰٫۲ C. Additionally, dressings, in dry and hydrated forms, caused no image distortion in any MRI scan performed. Evaluation of MRI safety and compatibility revealed no concerns for safety or image distortion in any of the silver-containing wound dressings tested thus it would be acceptable to leave these dressings intact during MRI. The ability to leave dressings in place during imaging will provide a significant benefit to patient care by reducing pain associated with dressing removal.
