Left frame shows magnetic eyelashes attached by single strings diagonally within container used as phantom to avoid merged artifact on imaging. Right frame is a susceptibility-weighted image showing large artifact arising from magnetic eyelashes. Images courtesy of American Journal of Roentgenology (AJR)
A new cosmetic product, magnetic eyelashes, should be of interest and concern to radiology professionals working in the MRI environment, according to a group of US researchers (Slonimsky E & Mamourian A. Magnetic Eyelashes: A New Source of MRI Artifacts. AJR Am J Roentgenol. 2019 Jul 24:1-3. doi: 10.2214/AJR.19.21550). False eyelashes are a growing segment of the cosmetics industry. In addition to the usual offerings, a new version uses magnets rather than glue to adhere the false eyelashes to the native lashes. Although the staff of the research group had little to no awareness of the existence of magnetic eyelashes, the Wall Street Journal has reported that instruction on their use and application was the top trending beauty-related search on Google in 2018. Einat Slonimsky and Alexander Mamourian at Penn State Health used a phantom to show that magnetic eyelashes worn during MRI can cause substantial artifacts “Our purpose was to evaluate the magnitude of the susceptibility artifacts created by magnetic eye-lashes on multiple standard imaging sequences and compare these artifacts with those created by aneurysm clips, which are a common source of image distortion,” wrote Slonimsky and Mamourian. Using two sets of magnetic eyelashes from the same manufacturer that were randomly selected and purchased online, a phantom was created by drilling multiple 2-mm holes in a plastic container and then running monofilament line through these holes to create a grid. The two sets of eyelashes were attached to single nylon strings, placed diagonally within the phantom. The phantom was then submerged in a container filled with distilled water, covered with a layer of plastic film to prevent free movement of the lashes, should they detach.
MRI was performed using a 3-T scanner with T2-weighted images, FLAIR images, T1-weighted images, susceptibility-weighted images, DW images, T1-weighted magnetization-prepared rapid-acquisition gradient-echo images, and T2-weighted sampling perfection with application-optimized contrasts using different flip-angle evolutions.
Ultimately, the magnetic eyelashes evidenced an artifact much larger than that created by the aneurysm clips (two made of cobalt alloy, one made of titanium) using the same sequences–measuring 7 × 6 cm maximal on susceptibility-weighted images, obscuring the entire phantom. Although the eyelashes stayed attached to the strings during the scan, upon removal of the phantom from the bore, one set of eyelashes detached from its string. Restrained by the plastic covering, it became attracted to the other eyelashes still attached to the phantom.
“Although friction and adhesion may differ from patient to patient, depending on the width and character of the native eyelashes of an individual,” Slonimsky and Mamourian wrote, “we strongly recommend inserting a line about magnetic eyelashes in the MRI safety questionnaire and adding stops in the screening system to prevent the entry of anyone with these lashes, including staff, into the MRI scanner room.” doi: 10.2214/AJR.19.21550