“Estimation of patent foramen ovale size using transcranial Doppler ultrasound in patients with ischemic stroke.” Grisold A, Rinner W, Paul A, Gabriel H, Klickovic U, Wolzt M, et al. Journal of Neuroimaging. 2021;1–7. https://lnkd.in/gwxTeQTi
These clinicians and researchers from the Medical University of Vienna, Austria, demonstrate that “TCD with step-wise barometric standardization allows an estimation of PFO size with good accuracy.” This article provides clinical evidence and direction for continuing ongoing efforts to delineate the role of PFOs in embolic strokes of undetermined source.
In their thought-provoking discussion, however, there is an issue that should be both controversial and fruitful for determining the next steps in clinical research. The authors argue that “…Although TCD is a clinically useful and highly sensitive screening tool, TEE justifiably represents the current gold standard for PFO diagnosis. In view of the more detailed anatomical assessment, TEE can be expected to remain the method of choice in the future.” Some stroke specialists are likely to modify that assessment with a “not so fast!”
The authors explain that “TCD might even be more sensitive than TEE for the detection of RLS…. without differentiating between a cardiac and an extracardiac shunt origin. As a result, TEE should be performed in case of a positive TCD indicating RLS. On the other hand, given the high sensitivity, one may argue that a negative TCD may be sufficient to exclude a clinically relevant RLS.” This should be further examined, as the authors’ work with step-wise barometric pressures gives an important insight and tool to refine technique and prognostications.