Echography and Doppler of the Brain

Foreword
Foreword
Acknowledgements
Contents
List of Videos
Part I: Technology, Views and Normal Echo Anatomy
1: Principles of Transcranial Doppler Ultrasonography
1.1 Introduction
1.2 Transcranial Doppler Ultrasonography
1.3 Transcranial Colour-Coded Duplex Ultrasonography
1.4 Final Remarks
References
2: Basic Anatomy with TCCD and Vessels
2.1 Introduction
2.2 Vascular Anatomy
2.2.1 The Circle of Willis
2.2.2 Vascular Anatomy Through the Temporal Window
2.2.3 Vascular Anatomy Through the Transorbital Window
2.2.4 Vascular Anatomy Through the Suboccipital Window
2.2.5 Vascular Anatomy Through the Submandibular Window
2.2.6 Sonography of Cerebral Veins and Sinus
2.3 Brain Anatomy with Ultrasonography
2.3.1 Anatomic Landmarks
2.3.2 Clinical Implications
2.3.2.1 Intracranial Hemorrhage
2.3.2.2 Epidural/Subdural Hematomas
2.3.2.3 Brain Midline Shift
2.3.2.4 Hydrocephalus
2.3.2.5 Stroke
2.4 Conclusion
References
3: Windows and the Practical Approach: The MOTOr
3.1 Introduction
3.2 Anatomy Abnormalities
3.3 Measurements and Basic Calculations
3.4 Setup
3.5 The MOTOr Approach
3.5.1 Mandibular
3.5.2 Occipital
3.5.3 Transtemporal
3.5.4 Orbital
3.5.4.1 Optic Nerve Sheath
3.6 Troubleshooting
3.7 Summary
References
4: Optic Nerve Sheath Diameter
4.1 Introduction
4.2 Anatomical Background
4.3 Technology and Methods
4.3.1 Technology
4.3.2 Methods
4.3.3 Normal Views
4.3.4 Feasibility and Reproducibility
4.4 Limits and Safety Issues
4.4.1 Limits
4.4.2 Safety
4.5 Recent Innovation and Future Perspectives
4.6 Conclusion
References
5: Limitations and Pitfalls
5.1 Introduction
5.2 Technical Considerations
5.2.1 Acquisition of Images
5.2.2 Accuracy of Quantitative Measurements
5.2.3 Ultrasound-Related Artifacts
5.3 Anatomical Considerations
5.4 Clinical Considerations
5.4.1 Harmful Effects of Ultrasound Exposure
5.4.2 Systemic Factors Related to Patients’ Cardiopulmonary State
5.4.3 Waveform Analysis in Acute Cerebrovascular Pathology
5.4.4 Cerebral Circulatory Arrest
5.5 Summary
References
6: The Minimal, Intermediate, and Advanced Skills: How to Boost Your Competencies
6.1 Introduction
6.2 TCD and TCCD
6.3 Training Strategies
6.4 Learning Through Technological Aid
6.5 Learning Through Guidelines and Practice Standards
6.6 Competence
References
Part II: Basic and Advanced Parameters
7: Flow Velocity, Pulsatility Index, Autoregulation, and Critical Closing Pressure
7.1 Introduction
7.2 Flow Velocity
7.3 Pulsatility Index
7.4 Critical Closing Pressure
7.5 Autoregulation
7.5.1 Static Autoregulation
7.5.2 Dynamic Autoregulation
7.5.3 Continuous Monitoring of Autoregulation
References
8: Transcranial Doppler and Optic Nerve Ultrasonography for  Non-invasive ICP Assessment
8.1 Introduction
8.2 TCD-Derived Pulsatility Index
8.3 Methods Based on the Calculation of Non-invasive CPP (nCPP)
8.3.1 Aaslid et al. [12] (nICPAaslid)
8.3.2 Czosnyka et al. [14] (nICPFVd)
8.3.3 Edouard et al. [16] (nICPEdouard)
8.3.4 Varsos et al. [18] (nICPCrCP)
8.3.5 Abecasis and Cardim et al. (Spectral nCPP) [24]
8.4 Methods Based on Mathematical Models Associating Cerebral Blood Flow Velocity and Arterial Blood Pressure
8.4.1 Black-Box Model for ICP Estimation (nICPBB)
8.4.2 Cerebrovascular Dynamics Model for Estimation of ICP [28, 32] (nICPHeldt)
8.4.3 Models Based on Non-linear Models Between Arterial Blood Pressure and Cerebral Blood Flow Velocity
8.4.3.1 Modified nICPBB
8.4.3.2 Data Mining
8.4.4 Semi-supervised Machine Learning
8.5 Optic Nerve Sheath Diameter Measurement
8.6 Take-Home Message for Clinicians
8.7 Final Remarks
References
9: Cerebral Perfusion: Practical Contributions of Transcranial Doppler at Bedside
9.1 Introduction
9.2 TCD: Velocity or Flow?
9.3 Detection of Conditions That Affect Cerebral Perfusion
9.3.1 Noninvasive Estimation of Intracranial Pressure (ICP)
9.3.2 Cerebral Vasospasm
9.3.3 Hyperperfusion
9.3.4 Hypoperfusion
9.3.5 Brain Death
9.4 Applications of TCD Evaluating Cerebral Perfusion in Common ICU Pathologies
9.4.1 Acute Stroke
9.4.2 Severe Traumatic Brain Injury
9.4.3 Post-out-of-hospital Cardiac Arrest Syndrome
9.4.4 Acute Liver Failure
9.5 Conclusion
References
Part III: Pathology and Clinical Applications: Emergency Department
10: Emergency Department and Prehospital Brain US as Part of POCUS and US Multiorgan Evaluation
10.1 Introduction
10.2 BUS in Stroke
10.3 BUS Within Whole-Body Ultrasound in Cardiac Arrest and the Post-resuscitation Syndrome
10.4 BUS Within Whole-Body Ultrasound in Multiple Trauma
References
Part IV: Pathology and Clinical Applications: General ICU
11: Sepsis, Liver Failure
11.1 Introduction
11.2 Sepsis
11.3 Liver Failure
11.4 Conclusion
References
12: Stroke
12.1 Introduction
12.2 Acute Ischemic Stroke
12.2.1 Diagnosis of Stroke Etiology
12.2.2 Diagnosis of Large Vessel Occlusion
12.2.3 Monitoring of Recanalization
12.2.4 Cerebral Autoregulation
12.2.5 Hemorrhagic Transformation
12.2.6 Midline Shift
12.2.7 Multimodal Neuromonitoring Approach
12.2.8 Sonothrombolysis
12.3 Conclusions
References
13: Cardiac Arrest
13.1 Introduction
13.2 TCD During Cardiopulmonary Resuscitation
13.3 Post-resuscitation Care and Neuro-Prognostication
13.4 Conclusions
References
14: Severe Respiratory Failure: ARDS and ECMO
14.1 Introduction
14.2 Brain Ultrasonography
14.2.1 PEEP and Recruitment Maneuvers
14.2.2 Prone Positioning
14.2.3 ECMO
14.2.4 Identification of Right-to-Left Shunt with TCD
14.3 General Ultrasonography
14.3.1 Lung Ultrasound
14.3.2 Cardiac Ultrasound
14.4 Conclusion
References
Part V: Pathology and Clinical Applications: Neuro-ICU
15: Intracerebral Hematomas, Midline Shift, Hydrocephalus
15.1 Introduction
15.2 Cerebral Hemodynamics
15.2.1 Pulsatility Index, Blood Flow Velocities, and Cerebral Autoregulation
15.3 Intracerebral Hematoma
15.4 Midline Shift
15.5 Other Parameters and Applications
15.5.1 Hydrocephalus
15.5.2 Subdural Hematomas
15.5.3 Cerebral Venous Drainage Assessment
15.6 Conclusions
15.7 Future Directions
References
16: Vasospasm After Subarachnoid Hemorrhage
16.1 Introduction
16.2 Pathophysiology of Cerebral Vasospasm and Delayed Cerebral Ischemia
16.3 Diagnosis of Cerebral Vasospasm and Delayed Cerebral Ischemia
16.4 Transcranial Doppler Principles
16.5 Other Diagnostics of Cerebral Vasospasm
16.6 Prevention of Vasospasm/Delayed Cerebral Ischemia
16.7 Management of Symptomatic Vasospasm
16.8 Conclusions
References
17: Brain US in the Neurological Settings
17.1 Introduction
17.2 Pseudotumor Cerebri Syndrome
17.3 Low-Pressure Syndromes, Cerebrospinal Fluid (CSF) Leaks, and Therapeutical Approaches: Intracranial Hypotension, Patch Test
17.4 Posterior Reversible Encephalopathy Syndrome (PRES)
17.5 Acute Mountain Sickness (AMS)
17.6 Optic Neuritis and Non-arteritic Ischemic Optic Neuropathy
17.7 Hydrocephalus
17.8 Infections of Central Nervous System
17.9 Intracranial Stenosis and Systemic Vasculitis
17.10 Parenchymal B Sonography in Neurodegenerative Diseases
17.11 Conclusion
References
18: Brain Death
18.1 Pathophysiology of Brain Death
18.2 Diagnosis
18.3 TCD Procedure
18.3.1 False-Positive and False-Negative Results
18.3.2 Other Tests
18.3.2.1 Cervical Colour Doppler
18.3.2.2 Optic Nerve Sheath Diameter
References
Part VI: Pathology and Clinical Applications: Applications in Neurosurgery
19: Intraoperative Echo in TBI
19.1 Introduction
19.2 Utility of ioUS in TBI
19.2.1 Intraoperative Use of US
19.2.2 Possible Scenarios
19.2.3 Explanatory Cases
19.2.3.1 Case n. 1
19.2.3.2 Case n. 2
19.3 Future Perspectives
References
20: Neurosonology in Tropical Medicine
20.1 Introduction
20.2 Neurosonology in Neurological Infections in the Tropics
20.3 Human Immunodeficiency Virus
20.4 Tuberculous Meningitis
20.4.1 Intracranial Hypertension in TBM
20.4.2 Tuberculous Meningitis-Related Vasculopathy
20.5 Cryptococcal Meningitis
20.5.1 Intracranial Hypertension in CrM
20.5.2 Vasculopathy in CrM
20.6 Neurocysticercosis
20.6.1 Intracranial Hypertension in Neurocysticercosis
20.6.2 Vasculopathy in NCC
20.7 Cerebral Malaria
20.7.1 Raised Intracranial Pressure in Paediatric CM
20.7.2 Transcranial Doppler in Paediatric CM
20.8 Neurosonology in Non-infectious Diseases in Tropical Regions
20.8.1 Sickle Cell Anaemia
20.8.2 Hydrocephalus
20.8.3 Traumatic Brain Injury
20.9 Implementation of Neurosonology in Health Systems in Low- and Middle-Income Countries
References
Part VII: Pathology and Clinical Applications: Specific Considerations
21: Pediatric Population (Pathology and Clinical Applications: Specific Considerations)
21.1 Introduction
21.2 Diagnostic Techniques
21.2.1 Transcranial Doppler Sonography (TCD)
21.2.2 Transorbital Imaging
21.2.3 Transcranial Imaging
21.3 Image-Guided Therapeutic Interventions
21.4 Intraoperative Navigation
References
22: Brain Ultrasound in the Critically Ill Pregnant and Puerperium Women
22.1 Introduction
22.2 Brain Ultrasound
22.3 Normal Cerebral Physiology in Pregnancy
22.4 Unique Brain Diseases of Pregnancy and Puerperium
22.4.1 Preeclampsia and Eclampsia
22.4.1.1 Role of BUS
22.4.2 Postpartum Angiopathy
22.4.2.1 Role of BUS
22.4.3 Cerebral Venous Sinus Thrombosis
22.4.3.1 Role of BUS
22.5 Conclusions
References
Part VIII: Pathology and Clinical Applications: Intraoperative Applications
23: Intraoperative Application of Brain Ultrasound in Non-cardiac Surgery
23.1 Introduction
23.2 Techniques and Methods
23.2.1 Assessment of CBF: TCD and TCCD
23.2.2 Estimation of CPP and ICP
23.2.3 Embolism Detection
23.3 Clinical Applications
23.3.1 Vascular Surgery: Carotid Endarterectomy
23.3.2 Pneumoperitoneum and Prone Position
23.3.2.1 How Can We Monitor ICP?
23.3.3 Beach Chair Position and Orthopaedic Surgery
References
24: Cardiac Surgery
24.1 Introduction
24.2 Basic POCUS-B in Cardiac Surgery
24.3 Brain Ultrasound Monitoring in Paediatric Cardiac Surgery
24.3.1 Usefulness of Preoperative Brain Ultrasonography in Paediatric Cardiac Surgery
24.3.2 Usefulness of Intraoperative Brain Ultrasonography in Paediatric Cardiac Surgery
24.3.2.1 Transcranial Doppler in Paediatric CHD Surgery
24.3.2.2 Role of TCD During Deep Hypothermic Cardiopulmonary Bypass (DHCPB), Deep Hypothermic Circulatory Arrest (DHCA) and Low-Flow Cardiopulmonary Bypass
24.3.2.3 Role of TCD During Regional Low-Flow Perfusion (RLFP) for Neonatal Aortic Arch Reconstruction
24.3.2.4 Role of TCD for Detecting Cerebral Emboli
24.4 Brain Ultrasound Monitoring in Adult Cardiac Surgery
24.4.1 Preoperative Transcranial Doppler
24.4.1.1 Preoperative Transcranial Doppler and Short-Term POCD
24.4.1.2 Preoperative Transcranial Doppler and Long-Term POCD
24.4.1.3 Preoperative Transcranial Doppler and Cerebral Autoregulation Before Cardiac Surgery
24.4.1.4 Preoperative Transcranial Doppler and Right-to-Left Intra-cardiac Shunt
24.4.2 Intraoperative Use of Transcranial Doppler
24.4.2.1 Transcranial Doppler for Evaluation of Cerebral Autoregulation (CA)
24.4.2.2 Transcranial Doppler to Monitor Cerebral Perfusion During Cardiac Surgery
Detection of Cerebral Hypotension During Off-Pump Versus On-Pump CABG
Detection of Cerebral Hyperperfusion During Cardiac Surgery
Detection of Efficacy of Selective Cerebral Perfusion During Deep Hypothermic Circulatory Arrest
24.4.2.3 Transcranial Doppler to Detect Cerebral Emboli During Cardiac Surgery
Technique
TCD Versus TEE for Detection of Cerebral Embolism
TCD-Detectable Cerebral Embolism and Aortic Atheroma
TCD-Detectable Emboli and Timing of Embolic Events During Cardiac Surgery
TCD-Detectable Cerebral Emboli and CPB Techniques During Cardiac Surgery and ECMO
TCD and Cerebral Embolus Differentiation (Particulate or Gaseous)
24.5 Multimodal Neurologic Monitoring in Cardiac Surgery
24.6 Limitations of Transcranial Doppler in Cardiac Surgery
24.7 Conclusions
References
Part IX: Clinical Cases
25: Case 1: Vasospasm Treated with Intra-Arterial Nimodipine
26: Case 2: Vasospasm Treated with Ballooning Angioplasty
27: Case 3: Vasospasm Treated with Ballooning Angioplasty
28: Case 4: aSAH during Pregnancy
29: Case 5: Intracranial Hypertension and Decompressive Craniectomy in Severe aSAH
30: Case 6: Brain Ultrasound for EVD Weaning
31: Case 7: Posterior Cranial Fossa Brain Tumor in a Pediatric Patient
32: Case 8: Cerebral Circulatory Arrest
33: Case 9: Intracranial Hypertension and Hydrocephalus
34: Case 10: Intracranial Hypertension and Decompressive Craniectomy
35: Case 11: Hydrocephalus with Ventricular Vegetations
36: Case 12: Intracranial Hypertension after Ischemic Stroke