Neurovascular Sonography

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