LAUSR

BACKGROUND It is unknown whether contrast transcranial color-coded sonography of vertebral artery monitoring via the foramen magnum window (cTCCS-VA) is useful to detect right-to-left shunt (RLS). We investigated whether cTCCS-VA can be proposed as an alternative to middle cerebral artery monitoring via the temporal bone window (cTCCS-MCA) for RLS detection, as compared with contrast transesophageal echocardiography (cTEE). METHODS We evaluated 112 patients with ischemic stroke or transient ischemic attack. We compared the sufficiency of both acoustic windows in each age tertile. Then, we analyzed the accuracy of cTCCS in diagnosing an RLS for a patent foramen ovale (PFO) detected by cTEE. RESULTS In the higher-age tertile, the foramen magnum window was significantly more sufficient than the temporal bone window (100% vs. 71%, p<0.001). In 94 patients having both windows, diagnosis of an RLS using cTCCS-MCA revealed a specificity of 42%, and a sensitivity of 84%. Diagnosis of an RLS using cTCCS-VA revealed a specificity of 40%, and a sensitivity of 91%. Analysis of the subgroup with large PFOs revealed a specificity of 71% using both cTCCS-MCA and cTCCS-VA. CONCLUSIONS cTCCS-VA should play an important role in detecting an RLS, especially in elderly stroke patients having large PFOs.