This book provides a comprehensive and concise, review of the fundamental concepts and clinical indications for Transcranial Doppler (TCD) imaging. An overview of the physics of ultrasonography as it pertains to TCD is presented, as well as neuroanatomy and cerebrovascular physiology in healthy and diseased states. Recommended protocols for neuroimaging are reviewed and serves as a guide for existing neurovascular laboratories and medical systems seeking to develop laboratories that are in need of a guide to establish their own protocols.
The most common, relevant and challenging clinical conditions where TCD is incorporated to assist with patient management are discussed. In addition, chapters provide a framework for building a neurovascular laboratory, including necessary equipment, steps to obtain national accreditation by accrediting bodies, and reimbursement procedures for tests performed. The book concludes with “clinical pearls” and “tricks of the trade”, which serve as a commentary to guide physicians and neurosonologists on best-practices for TCD acquisition and interpretation.
Author(s): Wendy C. Ziai, Christy L. Cornwell
Publisher: Springer
Year: 2022
Language: English
Pages: 538
City: Cham
Foreword
Preface and Acknowledgments
Contents
Contributors
Principles of Transcranial Doppler Sonography
Introduction
Ultrasound
Sound
Wave Parameters (Fig. 2)
Propagation Speed
Impedance
Reflection and Scatter
Scattering
Introduction to Doppler Ultrasound
Transducer
Ultrasound Beam
Attenuation
Methods of Compensating for Attenuation
Doppler Effect
Blood as Moving Scatterers
Doppler Equation
Doppler Angle
Pulsed-Wave Doppler
Range Gating
Additional Parameters Inherent to Pulsed-Wave Doppler
Pulse Duration and Spatial Pulse Length
Pulse Repetition Frequency, Pulse Repetition Period and Duty Factor
Pulse Repetition Frequency (PRF)
Range Ambiguity
Doppler Processes and Instruments
Audio
Spectral Analysis
Additional Methods of Doppler Signal Processing
Transcranial Color Doppler Imaging (TCDI)
Two Channel TCD
Power M-mode
Multi-depth
Safety
Mechanical Index (MI)
Thermal Index (TIS, TIB, TIC)
Conditions Specific to Transcranial Doppler
Transorbital Approach
References
Overview of Pertinent Cerebral Vascular Anatomy
Anatomical Variations
Internal Carotid Artery Segments [4] (Fig. 3)
Middle Cerebral Artery
Anterior Cerebral Artery (Proximal Segments)
Basilar Artery
Posterior Cerebral Artery [7]
Venous System
Locations for Transcranial Doppler Probes
Identifying Intracranial Vessels
Evaluating Collateral Circulations
References
Cerebral Waveforms for Hemodynamic Assessment
References
Transcranial Doppler for Monitoring in the Neurocritical Care Unit
Introduction
Transcranial Doppler
Transcranial Color-Coded Ultrasound
Future Perspectives
Conclusion and Recommendations
References
Transcranial Doppler in Subarachnoid Hemorrhage
Introduction to Subarachnoid Hemorrhage
Cerebral Vasospasm in SAH
Detection of Cerebral Vasospasm
The Role of TCD in Cerebral Vasospasm Detection and Management Following SAH
TCD and Cerebral Autoregulation in SAH
TCD and Emboli Detection
Conclusions
References
Reversible Cerebral Vasoconstriction Syndrome (RCVS) and Vasculitis
Introduction
Literature Review
TCD to Detect Stenosis and Occlusion
Anterior Circulation
Posterior Circulation
Vasospasm and SAH
Hemodynamic Effects in Vasospasm
RCVS
RCVS v Vasculitis
Vasculitis
TCD Findings in Vasculitis
Suggested Protocol
Technical Considerations
References
Monitoring for Emboli Detection (Without and With Microbubbles)
Monitoring for Emboli Detection (Without Micro-Bubbles Injection)
Monitoring for Emboli with Micro-Bubble Injection
Conclusion
References
Evaluation of Cerebral Circulatory Arrest
Development
Conclusions
Personal Perspectives
References
Intracranial Stenosis
Definition
Etiology
Complications
Differential Diagnosis
Transcranial Doppler Results
Other Procedures
Treatment
Conclusions
Personal Perspectives
References
Therapeutic TCD for Patients with Acute Cerebral Ischemia
Criteria and References
Conclusions
Personal Perspectives
References
Clinical Application of Cerebrovascular Physiology
Introduction
Cerebrovascular Anatomy and Physiology: An Overview
Cerebral Blood Flow and Autoregulation
Effect of Blood Pressure on Autoregulation
Carbon Dioxide and Autoregulation
Autoregulatory Processes During Acute Stroke
Subarachnoid Hemorrhage and Cerebral Autoregulation
Conclusion
References
Adult Traumatic Brain Injury
Introduction
Epidemiology
Pathophysiology
Defining the Disease
Mild – Moderate TBI
Severe TBI
Signs and Symptoms
Complications
Differential Diagnosis
TCD Findings
Other Imaging
Computed Tomography (CT)
Magnetic Resonance Imaging (MRI)
Positron Emission Tomography (PET)
Electroencephalography (EEG)
Treatment
Summary
References
Traumatic Brain Injury – Pediatric
Non-invasive Estimate of ICP
Non-invasive Estimate of CPP
Autoregulation and Continuous Monitoring of TCD Signals
Detect Regional Variations on Cerebral Hemodynamics
Diagnosis of Brain Death
Conclusions
References
Cerebrovascular Reactivity Assessments in Traumatic Brain Injury
Introduction
Current Standard Monitoring of Cerebrovascular Reactivity in TBI
Application of TCD for Cerebrovascular Reactivity Monitoring in TBI
Intermittent Methodologies
Continuous Methodologies
Recent Advances in Continuous Cerebrovascular Reactivity Monitoring
TCD Derived Indices in Adult TBI
Association with Global Outcome
Which Component of TCD Flow Velocity Is Best?
Future for Entirely Non-invasive Means of Continuous Cerebrovascular Reactivity Monitoring
Conclusions
References
Transcranial Doppler Protocols and Procedures: Vasomotor Reactivity
Introduction
Indications for Vasomotor Reactivity and Breath-Holding [1, 2, 3]
CO2 Delivery System Set Up: (Courtesy of Cedars-Sinai Medical Center)
Procedure
Alternate Procedure Without Capnometry
Calculations [3]
Results
Breath-Holding Method
Procedure [2]
Calculations [2]
Results
References
Continuous Cerebral Autoregulation Monitoring Using TCD
Background
Step by Step Using Analog Hemodynamic Monitors (Fig. 1)
Step by Step with Digital Hemodynamic Monitors
Limitations
References
Optic Nerve Sheath Diameter for Increased Intracranial Pressure
Introduction
The Physiology Supporting ONSD Measurements
Clinical Application of ONSD Measurements
Equipment and Supplies Needed to Obtain ONSD Measurements
Interpretation of ONSD Measurements for Adult Patients
Interpretation of ONSD Measurements for Pediatric Patients
Limitations
Conclusion
References
Cranial Ultrasound
Cranial Anatomy on B Mode Ultrasound
References
Applications of Transcranial Doppler Ultrasonography in Sickle Cell Disease, Stroke, and Critical Illness in Children
Background
Childhood Stroke and Arteriopathies
Sickle Cell Disease (SCD) in Children
Other Childhood Arteriopathies
Pediatric Critical Care Applications
Moderate to Severe TBI
Cerebral Vasospasm
Monitoring During ECMO
Brain Death
Other Conditions
Conclusions
References
Point of Care Transcranial Doppler
Introduction
References
Cerebrovascular Physiology in the Setting of Temporary and Durable Mechanical Circulatory Support
Introduction
Structural Components and Design of Left Ventricular Assist Devices
Stroke Incidence in the Setting of Durable Mechanical Circulatory Support
Blood Pressure Considerations and Impact on Cerebrovascular Physiology and Outcomes
Stroke Mechanisms Among Patients Supported by CF-LVADS
Impact of CF-LVAD Support on Cerebrovascular Physiology
Cerebral Microembolic Events in the Setting of CF-LVAD Support
Extracorporeal Membrane Oxygenation, Cerebrovascular Physiology, and Outcomes
Conclusion
Personal Perspective
References
Electroencephalography Versus Transcranial Doppler Ultrasonography; Indications and Applications for Intracranial Monitoring
Introduction
TCD Versus EEG in Common Clinical Scenarios
Conclusion
Quality of Level Rating
Strength of Recommendation Rating
References
Moyamoya Disease
Epidemiology
Etiology
Clinical Features
Differential Diagnosis
Role of Transcranial Doppler
Internal Carotid Artery
Middle Cerebral Artery
Posterior Cerebral Artery
Microembolic Signals (MES) in Moyamoya
Autoregulation and Vasomotor Reactivity
Other Procedures
Treatment
Case 1
Case 2
References
Vertebral Steal
Introduction
Brief Anatomy of the Vertebrobasilar Arterial System and Antegrade Flow
Subclavian-Vertebral Artery Steal Syndrome (SSS)
Conclusions
References
Transcranial Doppler in Acute Bacterial Meningitis
Cerebral Metabolism in Acute Bacterial Meningitis
Cerebral Blood Flow in Acute Bacterial Meningitis
Transcranial Doppler and Evaluation of Cerebrovascular Involvement
Cerebral Autoregulation in Acute Bacterial Meningitis
Vasoreactivity in Acute Bacterial Meningitis
Summary
References
TCD Equipment, Lab Accreditation, Reimbursement, and Practice Issues
Introduction
TCD
TCCD
Image Storage and Retrieval
Reporting
Examination
Accreditation
Reimbursement
Certification of Interpreting Physicians
Conclusions
References
Use of Transcranial Doppler in the Outpatient Ultrasound Lab
TCD in the Dedicated Neurovascular Ultrasound Lab
An Indispensable Tool for Clinical and Academic Medical Center Research
A’s TCD Narrative
ESUS and Cryptogenic Stroke
References
Part I: Protocols
Transcranial Doppler Non-Imaging for Adults
Introduction
Indications for Transcranial Doppler
Equipment
Limitations
Procedure
Patient Positioning
TCD Acoustic Windows
Begin Procedure with Insonation of the Middle Cerebral Artery (MCA)
ACA/MCA Bifurcation
Anterior Cerebral Artery (ACA)
Terminal Internal Carotid Artery (tICA)
Posterior Cerebral Artery (PCA)
Obtain Lindegaard Ratio
Vertebral Arteries and Basilar Artery Can Be Insonated in the Suboccipital Window
Transorbital Window for Insonation of the Ophthalmic Artery and Carotid Siphon
Vasospasm
Documentation
Review of the Diagnostic Exam Findings
Spectral Doppler Waveform Examples
References
Transcranial Color Doppler Imaging for Adults
Introduction
Procedure and Purpose
Indications
Limitations
Equipment
Supplies
Equipment Quality and Control
Patient Assessment and Communication
Performance Protocol and Technique
Comments on Angle Correction
Finding the Temporal Bone Window
The Bifurcation Landmark
Finding the Transorbital Window
Considerations
Finding the Submandibular Window
Documentation
Diagnostic Findings (Fig. 11)
Report Example
References
TCD Procedures and Protocols: Protocol for Monitoring for Emboli Detection (and With Microbubbles)
Reporting
Agitated Saline Protocol: TCD Bubble Study
Reporting
Protocol for Procedures: How to Obtain Measurements of the Optic Nerve Sheath Diameter in Adults and Children Utilizing Point-of-Care Ophthalmic Ultrasonography
Introduction
Suggested Training for Obtaining Ultrasound Guided ONSD Measurements
How to Set Up the Ultrasound and the Patient
How to Obtain Optic Nerve Sheath Diameter Images
How to Measure the ONSD from Saved Images
Interpretation of ONSD Measurements for Adult Patients
Interpretation of ONSD Measurements for Pediatric Patients
Conclusion
References
Protocol for Extracranial Carotid Examination
Introduction
The Carotid Arterial Examination
Indications
Equipment
Description of Procedure
Anatomic Variations
Documentation
Interpretation
References
Index
