- Poster presentation
- Open Access
The value of MRA images for identifying intraplaque hemorrhage in carotid plaque
© Qiao et al; licensee BioMed Central Ltd. 2010
- Published: 21 January 2010
- Independent Reader
- Mask Image
- Intraplaque Hemorrhage
- Hyperintense Region
- Standard Workup
MR angiography (MRA) has become a standard workup for carotid atherosclerosis, using either contrast-enhanced (CE) or time-of-flight (TOF) techniques. This provides a measure of narrowing but does not identify plaque components that indicate risk of rupture, such as the presence of intraplaque hemorrhage (IPH). CE and TOF techniques employ highly T1-weighted 3D gradient-echo sequences, and have the potential to detect IPH because of T1 short blood products.
We sought to determine whether IPH can be detected using either TOF or pre-contrast CEMRA (mask) images alone as part of the standard MRA workup, and if so, which is more reliable and accurate.
Carotid MRA scans were performed at 3 T on 10 patients (age range = 58-86 y, 80% male) scheduled for carotid endarterectomy (CEA) for stenosis. A 3D TOF MRA was acquired with the following parameters: TR/TE/flip angle, 23 msec/3.5 msec/25°; voxel size, 0.6 × 0.8 × 1 mm. A CEMRA was acquired before (mask image) and after contrast administration with the following parameters: TR/TE/flip angle, 6.0 msec/2.0 msec/30°; voxel size, 0.7 × 0.7 × 1 mm. The source images of both MRA sequences were reconstructed to a transverse plane. CEA specimens were matched to the MRI images and stained with glycophorin A and Mallory's stain to detect IPH. MR images were de-identified and reviewed randomly by two independent readers for IPH presence (identified as hyperintense regions compared to adjacent muscle (1)). The sensitivity, specificity, positive and negative predictive values (PPV and NPV) for IPH detection were calculated. Inter- and intra-observer agreements were determined by Cohen's kappa statistics.
Comparison of two MRA techniques for IPH detection
Positive Predictive Value (%)
Negative Predictive Value (%)
CEMRA mask images are highly accurate and reliable for identifying IPH, more so than the TOF sequence, and can provide valuable information about risk for rupture.