Vertebrobasilar Recording with Contrast Transcranial Doppler in Right-to-Left Shunt Diagnosis

Comparison of Vertebral Artery and Middle Cerebral Artery Monitoring for Right-to-left Shunt Detection by Contrast-enhanced Transcranial Doppler

“…Monitoring at the carotid artery might be considered a possible alternative method, but it has not been included in broad clinical practice 7 8 . c-TCD with vertebrobasilar monitoring has also been considered and compared for detecting RLS 9 10 . The aim of our study was to further establish whether c-TCD with vertebral artery (VA) monitoring is as effective as middle cerebral artery (MCA) monitoring for RLS detection in a Chinese population.…”

Alternative Ultrasound Windows and Sensitivity of Contrast Transcranial Doppler in Patients with Patent Foramen Ovale

“…For this purpose, transorbital insonation of the carotid siphon was used in this study [1] . Likewise, cervical insonation of the common carotid artery [4] submandibular insonation of the internal carotid artery [5] , transforaminal insonation of vertebral and basilar arteries [6][7][8] or even insonation of more peripheral arteries, such as the contralateral brachial or femoral arteries [9] , can be performed. However, none of the studies tested the utility of these techniques in patients with insufficient transtemporal bone windows.…”

Reply to the Letter by Morelli et al: Vertebrobasilar Recording with Contrast Transcranial Doppler in Right-to-Left Shunt Diagnosis

“…However, the high sensitivity for the detection of medium to large shunts may indicate that this technique can reliably detect clinically significant shunts. We would still advocate the use of the common femoral artery when a temporal window is absent, as this is a simple sensitive alternative with a high positive predictive value of 92.3% for detection of a patent foramen ovale [2] .We thank Morelli et al [1] for their interest in our paper on peripheral artery detection of a venous-to-arterial circulation shunt [2] .The use of an occipital window is not a technique that we have tried when investigating shunts. We found that there was too much interference when we tried to use two 2-MHz probes to insonate the middle cerebral artery and the common carotid artery.…”

“…We found that there was too much interference when we tried to use two 2-MHz probes to insonate the middle cerebral artery and the common carotid artery. This could be a problem with insonation of the basilar artery, and we wonder whether Morelli et al [1] used two probes with different frequencies. We had considerable difficulty in holding the probe on the common carotid, especially during provocation with coughing and the Valsalva maneuver.…”