Transcranial Doppler Ultrasound (TCD) and Intraoperative TCD Monitoring: Perspective

Abstract

Today it seems prudent to reconsider how ultrasound technology can be used for providing intra-operative
neurophysiologic monitoring that will result in better patient outcomes and decreased length and cost of hospitalization.
An extensive and rapidly growing literature suggests that the essential hemodynamic information provided by
transcranial Doppler (TCD) ultrasonography monitoring will provide effective neuromonitoring for improving
outcomes after different types of cardiovascular, cardiothoracic, and some endovascular interventional or diagnostic
procedures, like cardiac catheterization or cerebral angiography. Understanding, avoiding and preventing peri- or
postoperative complications, including neurological deficits following abovementioned surgeries or endovascular
intervention or diagnostic procedures represents an area of great public and economic benefit for society, especially
considering the aging population. At present, experience with TCD technique includes the ability to measure
cerebral blood flow velocity and identify cerebral microemboli. Continuous TCD monitoring along with systemic
hemodynamics will provide a better understanding of mechanisms of cerebral ischemic events that may occur during
or after surgical or endovascular procedures. Neuroprotective interventions based on multimodal neurological
monitoring that includes TCD modality would ideally eliminate postoperative cerebral ischemic events and improve
patient outcomes. However, widespread TCD monitoring clinical application in Operating Room or angiographic
unit settings is currently hindering by the absence of specific CPT (Current Procedural Terminology) code for its
utilization. Therefore, there is a critical need for creation of new CPT code for TCD monitoring in Operating Room
or during endovascular diagnostic and therapeutic procedures that will prevent cerebral adverse events during or after
abovementioned procedures.