Diagnostic value of acoustic radiation force impulse imaging combined with contrast-enhanced ultrasound in patients with acute cerebral ischemia / 中国中西医结合急救杂志

ABSTRACT

Objective To investigate the value of acoustic radiation force impulse imaging (ARFI) combined with contrast-enhanced ultrasound (CEUS) in diagnosis of acute cerebral ischemia (ACI) in patients with carotid artery vulnerable plaque (VP). Methods One hundred and ten patients with carotid artery VP diagnosed by routine ultrasound admitted to Renhe Hospital Affiliated to Three Gorges University from October 2017 to January 2019 were selected as subjects, including 59 patients with ACI (ACI group) and 51 patients with non-ACI (non-ACI group) confirmed by magnetic resonance imaging (MRI). All patients underwent routine ultrasound, CEUS and ARFI examinations, the differences in sizes of VP, shear wave velocity (SWV) and enhancement intensity (EI) were compared, and the diagnostic values of SWV and EI were evaluated by the analyses of receiver operating characteristic curve (ROC). Results Two hundred and ten VPs were found in 110 patients, including 112 grade 1 plaques, 53 grade 2 plaques, and 45 grade 3 plaques, compared with grade 1 plaques, the proportion of mixed echo (MP) and strong echo (SP) in grade 2 plaques, and the proportion of all echo types in grade 3 plaques were all significantly different from that of grade 1 plaques (all P < 0.05); compared with grade 1 plaques, the proportion of grade 2 plaques with thickness ≤ 2.0 mm, and the proportion of grade 3 plaques with thickness ≤ 2.0 mm and more than 3.1 mm were all significantly different from that of grade 1 plaques (all P < 0.05). SWV in ACI group was obviously lower than that in non-ACI group (m/s 1.91±0.54 vs. 2.41±0.57), and EI in ACI group was significantly higher than that in non-ACI group (dB 3.62±1.13 vs. 2.81±1.05), the difference being statistically significant (both P < 0.05). The area under the ROC curve (AUC) of SWV was 0.681 and the cutoff value was 2.21 m/s, sensitivity, specificity, positive predictive value and negative predictive value were 83.05%, 80.39%, 83.05%, 80.39%; the AUC of EI was 0.638, and the cutoff value was 3.71 dB, sensitivity, specificity, positive predictive value and negative predictive value were 79.66%, 74.51%, 78.33%, 76.00%. AUC of SWV combined with EI was 0.812, sensitivity, specificity, positive predictive value and negative predictive value were 93.22%, 94.12%, 94.83%, 92.31%, significantly higher than those of SWV or EI alone (all P < 0.05). Conclusion In ACI patients, the SWV of VP decreases and EI of VP increases, the detection efficacy of SWV combined with EI for diagnosis of ACI has relatively high clinical value, as the combined diagnostic efficiency is significantly higher than that of either SWV or EI alone.