Power M-Mode Transcranial Doppler for Diagnosis of Patent Foramen Ovale and Assessing Transcatheter Closure

Abstract

pmTCD provides greater sensitivity to contrast bubble emboli than does sgTCD. Among candidates for transcatheter closure, pmTCD provides an improved noninvasive method for diagnosing PFO and evaluating transcatheter closure.

Guidelines for the Echocardiographic Assessment of Atrial Septal Defect and Patent Foramen Ovale: From the American Society of Echocardiography and Society for Cardiac Angiography and Interventions

“…The results are reported referenced to a six-level Spencer logarithmic scale, and higher grades have been associated with larger right-to-left shunts. 111,112 The advantages of TCD over TEE and TTE include increased patient comfort (compared with TEE), semiquantitative assessment of shunt size, and the ability to identify extracardiac and intracardiac shunting. The identification of extracardiac shunts is also a limitation of TCD, because no anatomic information is provided regarding the location of the shunt or associated abnormalities.…”

The relationship between migraine and right-to-left shunt in children

“…The TCD was used to study the temporal window and specifically determining the presence/absence of RLS as described by other authors [13,19,28]. Briefly, agitated saline achieving a microbubble emulsion was injected as a bolus through an antecubital venous access, while recording the flow velocity of the middle cerebral artery, insonated through the temporal window on the right side at a depth of 20 mm.…”

Patent foramen ovale: A new disease?

“…In addition, it allows for reliable exclusion of other potential cardiac sources of embolism. TCD has recently been augmented by power Mmode, a new technology allowing power display with Doppler velocity and frequency signals over selectable depth ranges along the transducer beam [93]. Transcranial Doppler M-mode enhances sensitivity to contrast bubble emboli over single-gated TCD examination [94].…”