Contrast-enhanced ultrasound imaging improves diagnosis of cervical internal carotid artery pseudo occlusion.

OBJECTIVE

We aimed to assess the diagnostic effectiveness of contrast-enhanced ultrasound imaging for identifying pseudo occlusion and to compare disease-free survival (DFS) or recurrence-free survival (RFS) rates between surgical and nonsurgical interventions.

METHODS

We retrospectively analyzed data of 522 hospitalized patients with internal carotid artery occlusion diagnosed by cervical computed tomography angiography across four participating centers. In total, 149 participants who underwent contrast-enhanced ultrasound imaging and digital subtraction angiography were analyzed. The diagnostic performance of contrast-enhanced ultrasound imaging was evaluated using digital subtraction angiography as the reference standard. DFS or RFS rates were compared between true occlusion and pseudo occlusion and between surgical and nonsurgical cases in true occlusion and in pseudo occlusion, respectively.

RESULTS

Among 149 patients (median age, 66 [interquartile range, 60-72] years), comprising 127 (85.2%) male patients and 22 (14.8%) female patients, 84 had pseudo occlusion and 65 had true occlusion. Contrast-enhanced ultrasound imaging correctly identified pseudo occlusion in 78 patients, yielding an area under the curve of 0.810 (95% confidence interval, 0.747-0.872), a sensitivity of 92.9% (95% confidence interval, 87.0%-97.7%), and a specificity of 69.2% (95% confidence interval, 58.0%-80.3%). Key contrast-enhanced ultrasound findings included the "string sign" and "sponge-like sign" for pseudo occlusion and the "truncation sign" for true occlusion. DFS or RFS rates did not differ between true occlusion and pseudo occlusion (P = .413). Among pseudo occlusion cases, surgery improved DFS or RFS rates (P = .014), but not in true occlusion (P = .938).

CONCLUSIONS

Contrast-enhanced ultrasound imaging is a reliable imaging modality for differentiating pseudo occlusion from true occlusion in the cervical internal carotid artery. In addition, surgical intervention is associated with superior long-term outcomes in patients with pseudo occlusion.