Kassem, Mohamed, de Kam, Soraya S., van Velzen, Twan J., van der Geest, Rob, Wagner, Benjamin, Sokolska, Magdalena, Pizzini, Francesca B., Nederkoorn, Paul J., Rolf Jäger, H., Brown, Martin M., van Oostenbrugge, Robert J., Bonati, Leo H., and Eline Kooi, M.
[Display omitted] • Intraplaque hemorrhage can be identified on the routine mask images of CE-MRA. • High interobserver agreement for detecting IPH on MPRAGE, mask and TOF images. • TOF and mask images of CE-MRA have a lower image quality than MPRAGE images. Carotid intraplaque hemorrhage (IPH) on MRI predicts stroke. Magnetization-prepared rapid acquisition gradient (MP-RAGE) is widely used to detect IPH. CE-MRA is used routinely to assess stenosis. Initial studies indicated that IPH can be identified on mask images of CE-MRA, while Time-of-Flight (TOF) images were reported to have high specificity but lower sensitivity. We investigated the diagnostic accuracy of detecting IPH on mask images of CE-MRA and TOF. Thirty-six patients with ≥ 50% stenosis enrolled in the ongoing 2nd European Carotid Surgery Trial underwent carotid MRI. A 5-point quality score was used. Inter-observer agreement between two independent readers was determined. The sensitivity and specificity of IPH detection on mask MRA and TOF were calculated with MP-RAGE as a reference standard. Of the 36 patients included in the current analysis, 66/72 carotid arteries could be scored. The inter-observer agreements for identifying IPH on MP-RAGE, mask, and TOF were outstanding (κ: 0.93, 0.96, and 0.85). The image quality of mask (1.42 ± 0.66) and TOF (2.42 ± 0.66) was significantly lower than MP-RAGE (3.47 ± 0.61). When T1w images were used to delineate the outer carotid wall, very high specificities (>95%) of IPH detection on mask and TOF images were found, while the sensitivity was high for mask images (>81%) and poor for TOF (50–60%). Without these images, the specificity was still high (>97%), while the sensitivity reduced to 62–71%. Despite the lower image quality, routinely acquired mask images from CE-MRA, but not TOF, can be used as an alternative to MP-RAGE images to visualize IPH. [ABSTRACT FROM AUTHOR]