Duplex sonography of the brain-supplying arteries

Preface to the Seventh Edition
Notes on the Use of the Book
Contents
Editors and Authors
Part I: Basics
1: Anatomical Basics
1.1 Classification of Supraaortic Arteries
1.2 Aortic Arch Branches
1.2.1 Normal Anatomy
Note
Practical Tips
1.2.2 Anatomical Variations
Note
Summary
1.3 Extracranial Course of the Carotid Arteries
1.3.1 Normal Anatomy
Practical Tips
1.3.2 Anatomical Variations
Bifurcation Variants
Variants of the Carotid Bulb
Practical Tips
Kinkings and Coilings
Background Information
Practical Tips
Additional Carotid Artery Branches
Practical Tips
Variations of the Vessel Diameter
Summary
1.4 Cervical Course of the Vertebral Artery
1.4.1 Normal Anatomy
Practical Tips
1.4.2 Anatomical Variations
Summary
1.5 Intracranial Course of the Internal Carotid Artery
1.5.1 Normal Anatomy
Practical Tips
1.5.2 Anatomical Variations
Practical Tips
Summary
1.6 Vertebrobasilar Arteries
1.6.1 Normal Anatomy
1.6.2 Anatomical Variations
Summary
1.7 Intracerebral Arteries
1.7.1 Normal Anatomy
1.7.2 Anatomical Variations
Practical Tips
Summary
1.8 Collateral Connections
1.8.1 Extracranial Collaterals to the Anterior Cerebral Circulation
Practical Tips
Background Information
1.8.2 Extracranial Collaterals to the Posterior Cerebral Circulation
Background Information
1.8.3 Intracranial Collateral Connections
Practical Tips
1.8.4 Collaterals in Subclavian Artery Occlusions
Summary
1.9 Cerebrovascular Territories
1.9.1 Normal Anatomy
1.9.2 Anatomical Variations
References
2: Physiological Basics
2.1 Regulation of Arterial Blood Flow
2.1.1 Demand Regulation
2.1.2 Autoregulation
Summary
2.2 Cerebral Blood Flow Characteristics
2.2.1 Cerebral Blood Supply
Background Information
Note
2.2.2 Regulation of Cerebral Blood Flow
Background Information
Oxygen Extraction Rate
Note
2.2.3 Cerebral Perfusion Pressure
Summary
2.3 Arterial Flow
Summary
2.4 Flow Disturbance
2.4.1 Turbulence
Background Information
2.4.2 Flow Separation
Practical Tips
Summary
2.5 Pulsatile Flow in Arteries
Practical Tips
Summary
Reference
3: Basics of Ultrasound Technology
3.1 Basic Concepts of Diagnostic Ultrasound
3.1.1 Ultrasound Frequencies
3.1.2 Methods of Sound Transmission
3.1.3 Sound Probes
Background Information
3.1.4 Ultrasound Investigations
Background Information
Summary
3.2 Biological Ultrasound Parameters
3.2.1 Reflection
3.2.2 Scattering
Practical Tips
3.2.3 Attenuation
Note
Background Information
Summary
3.3 Technical Parameters of Diagnostic Ultrasound
3.3.1 Parameters of the Pulse-Echo Technique
3.3.2 Resolution
Practical Tips
3.3.3 Measures to Improve Ultrasound Image Quality
Background Information
Practical Tips
Practical Tips
3.4 Contrast-Assisted Procedures
3.4.1 Signal Amplified Doppler and Duplex Sonography
3.4.2 Contrast Harmonic Imaging
3.4.3 Stimulated Acoustic Emission (SAE)
Summary
3.5 Safety Aspects of Ultrasound Diagnostics
3.5.1 Thermal Effects
Technical Risk Factors
Biologically Induced Risk Factors
Practical Tips
3.5.2 Mechanical Effects (Cavitation)
Summary
References
4: Basics of Sonographic Flow Detection
4.1 Doppler Dependent Procedures
4.1.1 Doppler Effect
4.1.2 Application of the Doppler Effect to Blood Vessels
Practical Tips
4.1.3 Doppler Techniques
4.1.4 Acoustic Presentation of Doppler Signals
Background Information
Summary
4.2 Doppler Independent Techniques
4.2.1 B-Flow Technique
4.2.2 Possible Applications of B-flow Technique
Summary
4.3 Diagnostically Relevant Flow Parameters
5: Flow Assessment Using the Doppler Spectrum
5.1 Methodology of Spectrum Analysis
5.1.1 Fast Fourier Transformation (FFT)
Summary
5.2 Diagnostic Parameters of the Doppler Spectrum
5.2.1 Detection of Flow Direction
Practical Tips
5.2.2 Detection of Flow Velocity
Background Information
Systolic Maximum Frequency
End Diastolic Maximum Frequency
Mean Value
Systolic Maximum Frequency
End Diastolic Maximum Frequency
Mean Value
Practical Tips
5.2.3 Flow Disturbances
Note
5.2.4 Flow Characteristics (Pulsatility)
Practical Tips
Resistance Index (RI)
Pulsatility Index (PI)
Diastolic Ratio
Practical Tips
Practical Tips
Summary
5.3 Special Features of Pulsed Doppler Technology
5.3.1 Flow Assessment at Defined Tissue Depths
Size of the Sample Volume
Practical Tips
3D-Extension of the Sample Volume
5.3.2 Measurement of Flow Velocity
Note
``Unfavorable´´ Insonation Angle
Vessel Displayed Too ``short´´
Note
Poststenotic Flow Disturbances
Note
Elongations and Kinkings
Eccentrically Running Stenoses
Practical Tips
5.3.3 Measurement of Flow Volume
Background Information
Alternative to rCBF Measurements
``Abnormal´´ Vessel Diameters
Note
Problem of Vascular Pulsations
Problem of Vascular Borders
Problem of Cross Section Calculation
Problem of the Resolution
Note
Note
Practical Tips
5.3.4 Problems with the Aliasing Effect
Note
Summary
References
6: Flow Assessment Using Color Coding
6.1 Technical Principles of Color Coded Imaging
6.1.1 Color Coded Flow Detection
6.1.2 Parameters of the ``color window´´
6.1.3 Methods of Color Coded Presentation
6.1.4 Resolution of Color Coded Imaging
Axial Resolution
Lateral Resolution
Note
6.1.5 Special Methods of Color Coded Image Processing
Summary
6.2 Influencing Variables on Color Coded Flow Imaging
6.2.1 The Insonation Angle
6.2.2 Aliasing
Note
Practical Tips
6.2.3 Lower Cut-Off Frequency (Wall Filter)
6.2.4 Frame Rate
Background Information
6.2.5 Color Gain and Color Balance
Summary
6.3 Basic Techniques of Color Coded Duplex Examination
6.3.1 Optimized Vessel Imaging (``Low-flow setting´´)
Possibilities for Improving the ``color filling´´ of Vessels (``Low-Flow Setting´´)
Practical Tips
6.3.2 Optimized Flow Imaging
Summary
Part II: Investigation Techniques
7: Extracranial Doppler Sonography
7.1 Indications
Indications for CW Doppler Sonography of the Extracranial Arteries Supplying the Brain
7.2 Technical Settings
7.3 Examination of the Periorbital Arteries
7.3.1 Physiological Principles
7.3.2 Examination Procedure
Practical Tips
Practical Tips
7.3.3 Criteria for the Evaluation of Findings
Antegrade Signal with Enddiastolic Flow
Antegrade Signal Without Enddiastolic Flow
(Approximate) Zero Flow
Practical Tips
Retrograde Signal
Practical Tips
Increase in Flow
Decrease in Flow
Background Information
7.3.4 Possible Errors
Summary
7.4 Examination of the Carotid Bifurcation
7.4.1 Sound Distribution Levels
7.4.2 Examination Procedure
Practical Tips
Location
Pulsatility
Compression Maneuvers
Practical Tips
7.4.3 Diagnostic Criteria
7.4.4 Possible Errors
Summary
7.5 Examination of the Vertebral Artery
7.5.1 Examination Procedure
7.5.2 Diagnostic Criteria
Summary
7.6 Examination of the Subclavian Artery
7.6.1 Examination Procedure
7.6.2 Diagnostic Criteria
7.6.3 Possible Errors
Summary
8: Extracranial Duplex Sonography
8.1 Indications
Practical Tips
Indications for Extracranial Duplex Examination
8.2 Device Settings
Practical Tips
8.2.1 Ultrasound Transducers
8.2.2 B-mode Imaging
8.2.3 Color Coded Imaging
Note
8.2.4 Doppler Spectrum
Practical Tips
Practical Tips
Practical Tips
Recommended ``default settings´´ of the Duplex Device for the Examination of Extracranial brain Arteries
8.3 Examination of the Carotid Bifurcation
8.3.1 Diagnostic Sections
8.3.2 Examination Procedure
Practical Tips
Unclear Findings in Longitudinal Section
Quantification of Stenoses
Practical Tips
8.3.3 Diagnostic Criteria Using B-mode Imaging
Note
Practical Tips
8.3.4 Diagnostic Criteria Using Color Coded Imaging
Practical Tips
8.3.5 Diagnostic Criteria Using the Doppler Spectrum
Practical Tips
Practical Tips
Summary
8.4 Examination of the Vertebral Artery
8.4.1 Examination Procedure
Practical Tips
Practical Tips
Prevertebral Course (V1 Segment)
Vertebral Origin (V0 Segment)
Atlas Loop (V3 Segment)
8.4.2 Diagnostic Criteria
Practical Tips
Practical Tips
Flow Disturbances
Practical Tips
Summary
8.5 Error Sources
8.5.1 B-mode Imaging
Practical Tips
8.5.2 Doppler Spectrum
The Most Important Sources of Error When Determining Angle-Corrected Flow Velocity
8.5.3 Color Coded Imaging
Summary
9: Transcranial Doppler Sonography
9.1 Indications
9.2 Device Settings
9.2.1 Standard Setting
9.2.2 Insufficient Temporal Bone Window
9.3 Examination Procedure
9.3.1 Transtemporal Access
Practical Tips
Practical Tips
Middle Cerebral Artery
Posterior Cerebral Artery
9.3.2 Transorbital Access
Practical Tips
9.3.3 Transnuchal Access
Summary
9.4 Diagnostic Criteria
9.4.1 Doppler Frequencies
Additional Information
9.4.2 Flow Disturbances
9.4.3 Pulsatility
Summary
Reference
10: Transcranial Duplex Sonography
10.1 Indications
10.2 Device Settings
Practical Tips
10.2.1 Transducers
10.2.2 B-mode Imaging
10.2.3 Color Coded Imaging
Practical Tips
10.2.4 Doppler Spectrum
Practical Tips
Practical Tips
Recommended ``default settings´´ of the Duplex Device on the Intracranial Arteries Supplying the Brain
10.3 B-mode Sonography of the Brain
10.3.1 Ultrasonic Anatomy of the Brain
10.3.2 Ventricle Width Measurements
Summary
10.4 Color Coded Examination
Transcranial Duplex Examination in Non-Pathological Cases
10.4.1 Transtemporal Access
Practical Tips
Carotid T
Practical Tips
Top of Basilar Artery
Practical Tips
10.4.2 Transnuchal Access
Practical Tips
Curved Vessel Course
Vessel Course Outside the Insonation Plane
Summary
10.5 Diagnostic Criteria
10.5.1 B-mode Imaging
10.5.2 Color Coded Imaging
10.5.3 Dopppler Spectrum Analysis
Practical Tips
10.5.4 MCA/ICA Index (Lindegaard Index)
10.5.5 Asymmetry Index (Zanette Index)
10.5.6 Flow Disturbances
Practical Tips
10.5.7 Pulsatility
Summary
10.6 Duplex Sonography of the Intracranial Veins
References
11: Assessment of Intracranial Collateral Pathways
11.1 Indications
Indications for Assessment of Intracranial Collateral Pathways
11.1.1 Assessment of Existing Collateral Channels
11.1.2 Assessment of Future Collateral Pathways
11.2 Examination Procedure and Criteria
11.2.1 Localization of Collateral Vessels
Practical Tips
11.2.2 Functional Assessment of Collateral Pathways
Practical Tips
Summary
11.3 Findings in Different Collateral Pathways
11.3.1 Extra-Intracranial Collaterals
11.3.2 Circle of Willis
Note
11.3.3 Leptomeningeal Anastomoses
Sonographic Evidence of Collateral Pathways in the Closure of the Extracranial Internal Carotid Artery
Summary
References
12: Cerebrovascular Reserve Capacity
12.1 Indications
Practical Tips
12.2 Examination Procedure and Criteria
Background Information
Practical Tips
Practical Tips
Hyperventilation-Apnea Test
Practical Tips
Practical Tips
Summary
References
Part III: Findings in Stenoses and Occlusions
13: Stenoses and Occlusions of the Extracranial Carotid Artery
13.1 Stenoses of the Internal Carotid Artery
13.1.1 Definition of the Degree of Stenosis
Note
Practical Tips
Background Information
13.1.2 Main Criteria for Stenosis Grading
Practical Tips
Resolution Problems of Color Coding
Color Artifacts
Practical Tips
Background Information
Filiform Stenoses
Contralateral Carotid Occlusions
Short-/Long-Distance Stenoses
Tandem Stenoses
Narrow Vessels
Carotid Dissection
Collapsed Vessel
Note
Expected Poststenotic Velocities
Comparison with Intrastotic Flow Velocity
13.1.3 Additional Criteria for Stenosis Grading
Note
Progress Observations
Tandem Stenoses
Hyperperfusion
Maximum of a Stenosis Not Detected
Heavily Curved Vessel Course
13.1.4 Comparison with Other Methods
13.1.5 Follow-up Monitoring
13.1.6 Possible Errors
Short-Distance Stenosis
Acoustic Shadow
Tandem Stenosis
Collateralisation
Primary Slim Vessel
Eccentric Stenosis
Incorrect Insonation Angle
Overestimating Color Coding
Note
Summary
13.2 Stenoses of the Internal Carotid Artery Close to the Skull Base
Practical Tips
13.2.1 Diagnostic Criteria
Prestenotic Flow Velocity
Search for Multiple Stenoses
Practical Tips
13.2.2 Possible Errors
Note
13.3 Occlusions of the Internal Carotid Artery
13.3.1 Main Diagnostic Criteria
Practical Tips
Background Information
13.3.2 Additional Criteria for Occlusion Diagnosis
13.3.3 Differential Diagnostic Aspects
13.3.4 Possible Errors
Summary
13.4 Stenoses and Occlusions of the External Carotid Artery
13.4.1 Diagnostic Criteria in Stenoses
Practical Tips
13.4.2 Diagnostic Criteria in Occlusions
13.4.3 Possible Errors
Summary
13.5 Stenoses and Occlusions of the Common Carotid Artery
13.5.1 Diagnostic Criteria in Stenoses
13.5.2 Diagnostic Criteria in Occlusions
Summary
References
14: Stenoses and Occlusions of the Main Cerebral Arteries
14.1 Special Features of Intracranial Vascular Diagnostics
14.1.1 Numerous Causes of Intracranial Occlusions
14.1.2 Limitation to Flow Parameters
14.2 Stenoses of the Intracranial Carotid Artery
14.2.1 Diagnostic Criteria
Note
Practical Tips
Practical Tips
14.2.2 Accuracy and Possibilities of Error
Note
Degree of Stenosis Extracranial = Intracranial
Degree of Stenosis Extracranial Intracranial
Degree of Stenosis Extracranial Intracranial
Long-Distance Extra-/Intracranial Stenosis (Dissection)
Practical Tips
Summary
14.3 Stenoses of the Middle Cerebral Artery
14.3.1 Definition of the Degree of Stenosis
14.3.2 Diagnostic Criteria
Practical Tips
14.3.3 Differentiating Increased Flow Velocities
14.3.4 Accuracy and Possibilities of Error
Summary
14.4 Occlusions of the Intracranial Internal Carotid Artery
14.4.1 Diagnostic Criteria
Additional Information
14.4.2 Accuracy and Possibilities of Error
Note
Occlusion Before the Origin of the Ophthalmic Artery
Occlusion Before the Origin of the Posterior Communicating Artery
Occlusion After the Origin of the Posterior Communicating Artery
Summary
14.5 Occlusions of the Middle Cerebral Artery
14.5.1 Diagnostic Criteria
Carotid T-occlusion
Proximal Main Stem Obstruction of the Middle Cerebral Artery
Practical Tips
Distal Main Stem Obstruction of the Middle Cerebral Artery
Main Branch Occlusion of the Middle Cerebral Artery
Practical Tips
Occlusion of a Smaller Branch of the Middle Cerebral Artery
14.5.2 Accuracy and Possibilities of Error
Summary
14.6 Stenoses and Occlusions of the Other Cerebral Base Arteries
14.6.1 Stenoses and Occlusions of the Anterior Cerebral Artery
Examination of the Anterior Cerebral Artery
Examination of the Anterior Communicating Artery
Note
14.6.2 Stenoses and Occlusions of the Posterior Cerebral Artery
Normal Posterior Communicating Artery
Hypoplastic Posterior Communicating Artery
Summary
References
15: Stenoses and Occlusions in the Vertebrobasilar System
15.1 Stenoses and Occlusions of the Subclavian Artery
15.1.1 Auscultation and Palpation
Practical Tips
Practical Tips
15.1.2 Sonographic Findings in the Subclavian Artery
Doppler Spectrum
Note
Color Coded Imaging
15.1.3 Sonographic Findings in the Vertebral Artery
Beginning Subclavian Steal Effect
Practical Tips
Incomplete Subclavian Steal Effect
Complete Subclavian Steal Effect
Note
Summary
15.1.4 Sonographic Findings in the Basilar Artery
15.2 Stenoses and Occlusions of the Brachiocephalic Trunk
Note
15.3 Stenoses of the Vertebral and Basilar Artery
15.3.1 Special Features of Vascular Diagnostics in the Vertebral Artery
Note
15.3.2 Stenoses at the Origin of the Vertebral artery (V0)
15.3.3 Stenoses in the Prevertebral Course of the Vertebral Artery (V1)
15.3.4 Stenoses in the Intertransversal Course of the Vertebral Artery (V2)
Unstenosed Lumen Visible
Comparison with the V0/V1 Section
Vertebrobasilar Transition
15.3.5 Stenoses in the Area of the Atlas loop (V3)
15.3.6 Stenoses of the Intracranial Vertebral artery (V4) and Basilar Artery
Direct Assessment
Indirect Assessment
Practical Tips
Summary
15.4 Occlusions of the Vertebral and Basilar Arteries
15.4.1 Occlusions of the Proximal Vertebral Artery (V0-V1)
15.4.2 Occlusions in the Middle Section of the Vertebral Artery (V2-V3)
Practical Tips
15.4.3 Occlusions of the Distal Vertebral Artery (V4)
Note
Practical Tips
15.4.4 Occlusions of the Basilar Artery
Note
Summary
References
Part IV: Findings in Special Questions
16: Arteriosclerotic Vascular Diseases
16.1 Diffuse Arteriopathies
16.1.1 Diffuse Thickening of Vessel Walls
Risk Factors Described in the Literature for the Occurrence of Increased IMT in the Common Carotid Artery
Note
16.1.2 Dilated Arteriopathies
Note
Summary
16.2 Circumscribed Arteriopathies
16.2.1 Pathophysiology of Focal Arteriopathies
Frequency Distribution of Focally Circumscribed, Arteriosclerotic Vascular stenoses and Occlusions
Practical Tips
Note
16.2.2 Sonographic Assessment of the Degree of Stenosis
16.2.3 Sonographic Assessment of Plaque Morphology
Note
Information on Plaque Surface
Information on Plaque Structure
Information on Acoustic Shadowing
16.2.4 Clinical Significance of Sonographic Plaque Parameters
Sonomorphology Versus Surgical Specimen
Sonomorphology Versus Spontaneous Course
Summary
16.2.5 Ultrasound Parameters for the Indication of Carotid Surgery
References
17: Inflammatory Vascular Diseases
Causes of Secondary Systemic Vasculitis
17.1 Takayasu Arteritis
Early Diagnosis
Monitoring of Progress
Cerebral Hemodynamics
Summary
17.2 Cranial Arteritis
17.2.1 Findings in the Superficial Temporal Artery
Halo Sign
Absence of Vascular Pulsations
Presence of a Vessel Occlusion
Reduced Flow Velocity
Visible Vessel Wall during Compression
Case Study 17.1: Takayasu Arteritis
17.2.2 Findings on the Other Vessels
Summary
17.3 Primary Cerebral Vasculitis
17.4 Secondary Cerebral Vasculitis
17.4.1 Vasculitis in Purulent Meningitis
17.4.2 Other (Para)Infectious Vasculitis
Summary
Case Study 17.2: Cranial Arteritis
Case Study 17.3: Primary Cerebral Vasculitis
Case Study 17.4: Parainfectious Vasculitis
References
18: Arterial Dissections
Note
Internal Dissection
External Dissection
Note
18.1 Primary Extracranial Carotid Dissections
Intramural Bleeding
Detection of a ``False Lumen´´
Intimal Flap Detection
Short-Distance, ``Pointy´´ Stenoses (So-Called Bishop´s Mitre)
18.2 Primary Intracranial Carotid Dissections
Case Study 18.1: Aortic Arch Dissection
Short-Distance Dissection Close to the Skull Base
Case Study 18.2: Traumatic Dissection of the Common Carotid Artery
Note
Long-Distance, Proximally Extending Dissection
Case Study 18.3: Traumatic Dissection of the Extracranial Internal Carotid Artery
Case Study 18.4: Carotid and Vertebral Dissection After Marathon Run
Note
Vascular Occlusion Due to Dissection
Dissection in the Intracranial Carotid T-Area
Note
Case Study 18.5: Incorrect Findings of a Carotid Dissection with Anatomical Variant
18.3 Dissections of the Vertebral Artery
Case Study 18.6: Vertebral Artery Dissection After Chiropractic Treatment
Case Study 18.7: Spontaneous Vertebral Artery Dissection in the Distal V3 Segment
Note
Practical Tips
Summary
References
19: Other Vascular Diseases
19.1 Fibromuscular Dysplasia (FMD)
Additional information
Note
Practical Tips
Case Study 19.1: Fibromuscular Dysplasia of the Internal Carotid Artery
Summary
19.2 Moya Moya Disease
Case Study 19.2: Moya Moya Syndrome on Both Sides
Case Study 19.3: Moya Moya Syndrome with Bilateral Extra-intracranial Bypass
Case Study 19.4 Long-term Moya Moya Syndrome
Summary
19.3 Aneurysms
19.3.1 Extracranial Aneurysms
Secondary Aneurysm
Pseudoaneurysm
``False´´ Aneurysm (Aneurysm Spurium)
Carotid Bulb
Other Vessel Course
19.3.2 Intracranial Aneurysms
Summary
19.4 Carotidodynia
19.5 Reversible Cerebral Vasoconstriction Syndrome
References
20: Vascular Anomalies and Malformations
20.1 Kinkings and Coilings
20.1.1 Sonographic Assessment
Problem of Cranial Localization
Practical Tips
Problem of Angle Correction
20.1.2 Clinical Significance
Summary
20.2 Hypoplasia of the Carotid Artery
20.2.1 Sonographic Assessment
Differential Diagnostic Considerations for Suspected ``Hypoplasia´´ of the Internal Carotid Artery
20.2.2 Clinical Significance
Summary
20.3 Hypoplasia of the Vertebral Artery
20.3.1 Sonographic Assessment
Note
Note
Practical Tips
20.3.2 Clinical Significance
Indications of an Intermittent Compression Syndrome of the Vertebral Artery
Case Study 20.1: Head Rotation-dependent Compression of the Vertebral Artery
Case Study 20.2: ``Vertebrobasilar Insufficiency´´ in Severe Vertebral Hypoplasia
Note
Summary
20.4 Arteriovenous Malformations and Fistulas
20.4.1 Sonographic Assessment
Sonographic Findings in the Feeder Vessels of Arteriovenous Fistulas and Angiomas
20.4.2 Clinical Significance
Frequent Causes of Pulse Synchronous Ear Noises
Local Findings
Findings in Feeding Vessels
Case Study 20.3: Retroauricular AV Fistula
Intracranial Local Findings
Findings in the Periorbital Arteries
Extracranial Duplex Findings
Summary
References
21: Ultrasound Diagnostics in Acute Stroke
21.1 Emergency Diagnostics
21.1.1 Special Features of Emergency Diagnostics
Note
Practical Tips
21.1.2 Selection of the Sonographic Method
21.1.3 Localization Diagnostics
Occlusion of the Proximal Internal Carotid Artery
Occlusion of the Distal Internal Carotid Artery
Carotid T-occlusion
Practical Tips
Main Stem Occlusion of the Middle Cerebral Artery
Distal Main Stem Occlusion or Multiple Branch Occlusions of the Middle Cerebral Artery
Occlusion of the Proximal Vertebral Artery (V1/2 Segment)
Occlusion of the Distal Vertebral Artery (V3/4 Segment)
Basilar Artery Occlusion
21.1.4 Clinical Significance
Summary
21.2 Monitoring
21.2.1 Recanalization of Vascular Occlusions
Additional Information
21.2.2 Hyperperfusion
Use of the MCA/ICA Index
Summary
21.3 Etiologic Assessment
21.3.1 Differential Diagnosis of Stroke Etiology
21.3.2 Hemodynamic Assessment
Summary
References
22: Cerebral Vasospasms
22.1 Spontaneous Vasospasms
Case Study 22.1 (After Arning et al. 1998)
Summary
22.2 Vasospasms in Subarachnoid Hemorrhages
22.2.1 Basic Methodological Problems
Underestimation of Vasospasms
Overestimation of Vasospasms
Only Direct Assessment Reliable
Considering Angle Dependence
Consideration of Collateral Supply
22.2.2 Sonographic Assessment
Summary
22.3 Vasospasms in Inflammatory Brain Diseases
References
23: Diagnostics for Increased Cerebral Pressure and Cerebral Circulatory Arrest
23.1 Assessment of Elevated Cerebral Pressure
23.1.1 Doppler Sonographic Findings
Note
23.1.2 Influence of Disrupting Factors
23.2 Cerebral Circulatory Arrest
23.2.1 Doppler Sonography Versus Other Procedures
23.2.2 Doppler and Duplex Sonographic Findings
Practical Tips
Practical Tips
23.2.3 Examination Procedure
Practical Tips
Practical Tips
23.2.4 Problems of Transtemporal Assessment
Tachycardia
Arteriovenous Fistulas
Prolonged Brain Death
Open Fontanel
Large Open Skull Injuries
23.2.5 Requirements for the Examiner
23.2.6 Requirements for the Status Report
Summary
References
24: Ultrasound in Revascularization Procedures
24.1 Revascularizing Interventions of the Carotid Artery
24.1.1 Intraoperative Monitoring in Carotid Surgery
24.1.2 Postoperative Findings
Practical Tips
Practical Tips
Additional Information
Proximal Border of Resection
Practical Tips
Suture Area
External Carotid Artery
Distal End of the Resection
Secondary Aneurysm
Real Aneurysm
False Aneurysm
Infected Patch
Kinking Formations
Additional Information
24.1.3 Carotid Stenting
Additional Information
Stent Dislocation
Stent Fracture
Kinking at the Distal Stent End
24.1.4 Hyperperfusion Syndrome
Summary
24.2 Supraaortic Bypass Operations
Summary
24.3 Extra-intracranial Bypass Surgery
24.3.1 Preoperative Diagnostics
Evidence of Hemodynamic Failure
Evidence of an Intact External Carotid Artery
Evidence of a Large Caliber Superficial Temporal Artery
24.3.2 Postoperative Findings
Assessment of Pulsatility
Measurement of Flow Volume
Assessment of the Intracranial ``Watershed´´
Note
Summary
References
25: Cardiac Right-Left Shunt
25.1 Anatomy and Pathophysiology
25.2 Clinical Significance
25.3 Detection by Echocardiography
25.4 Detection by Transcranial Doppler sonography (PFO Test)
25.4.1 Ultrasonic Contrast Medium
Practical Tips
25.4.2 Doppler Sonographic Settings
25.4.3 Performing the PFO Test
Additional Information
Practical Tips
Procedure of the Transcranial PFO Test
Additional Information
Practical Tips
25.4.4 Doppler Sonographic Findings
25.4.5 Side Effects
Summary
References
26: Transorbital Sonography
26.1 Examination Procedure
Note
26.1.1 B-Scan of the Optic Nerve and Optic Sheath
26.1.2 Imaging of the Central Artery
26.2 Increased Intracranial Pressure
26.3 CSF Hypotension
26.4 Central Retinal Artery Occlusion
Note
Summary
References
Part V: Glossary and Standard Values
27: Glossary of Sonographic Terms
28: Standard Values
28.1 Extracranial Duplex Sonography
28.1.1 Common Carotid Artery
28.1.2 Internal Carotid Artery
28.1.3 External Carotid Artery
28.1.4 Vertebral Artery
28.2 Transcranial Doppler Sonography
28.2.1 Middle Cerebral Artery
28.2.2 Anterior Cerebral Artery
28.2.3 A Cerebri Posterior
28.2.4 Basilar Artery
28.3 Transcranial Color Coded Duplex Sonography
28.3.1 Middle Cerebral Artery (M1 Segment)
28.3.2 Anterior Cerebral Artery (A1 Segment)
28.3.3 (P1 Segment)
28.3.4 Vertebral Artery (V4 Segment)
28.3.5 Basilar Artery
28.4 Summary of Important Standard Values
References
Index