Published online before print January 3, 2008, doi: 10.1161/STROKEAHA.107.507095
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(Stroke. 2008;39:e45.)
© 2008 American Heart Association, Inc.
Letters to the Editor |
Response to Letter by Vatankhah et al
Department of Neurosciences, Ophthalmology and Genetics, University of Genova, Genova, Italy
Response:
We read with great interest Dr Vatankhah et al’s considerations on a possible alternative approach for right-to-left shunt diagnosis by means of common carotid duplex recording. In fact there are some reports on this technique, suggesting this possibility.1,2 Nevertheless, we think that there are at least 3 reasons to prefer a transoccipital approach in case of insufficient temporal window: neurologists are interested in the amount of contrast medium reaching the brain, both on anterior or posterior circulation; moreover, as the test has to be done during Valsava maneuver, it is very difficult to obtain a correct maneuver without moving the probe on the neck. Finally, there is no study comparing the test on middle cerebral artery with the test on common carotid artery; thus, it is impossible to quantify the amount of shunt that is of crucial importance for the stratification of embolic risk.
It would be interesting to plan a study comparing the test monitoring middle cerebral and common carotid arteries, in terms of sensitivity, specificity and possibility to give a quantification of the shunt.
Acknowledgments
Disclosures
None.
References
1. Teague SM, Sharma MK. Detection of paradoxical cerebral echo cointrast embolization by transcranial Doppler ultrasound. Stroke. 1991; 22: 740–745.
2. Draganski B, Blersch W, Holmer S, Koch H, May A, Bogdahn U, Hölscher T, Schlachetzki F. Detection of cardiac right-to-left shunts by contrast-enhanced harmonic carotid duplex sonography. J Ultrasound Med. 2005; 24: 1071–1076.
Related Article:
Stroke 2008 39: e44.
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