Neurosurgical Applications of Transcranial Doppler Sonography

1. Front Matter

   Pages I-X

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2. Introduction

   • Albrecht G. Harders

   Pages 1-1

3. Hemodynamic Principles

   • Albrecht G. Harders

   Pages 3-5

4. Prinicples of Ultrasound Doppler Sonography

   • Albrecht G. Harders

   Pages 6-11

5. Transcranial Doppler Device

   • Albrecht G. Harders

   Pages 12-15

6. Transcranial Doppler Investigation Technique

   • Albrecht G. Harders

   Pages 16-23

7. Normal Values

   • Albrecht G. Harders

   Pages 24-26

8. Blood Flow Velocity Changes Under Physiological Deviations

   • Albrecht G. Harders

   Pages 27-31

9. Spontaneous Subarachnoid Hemorrhage and Disturbed Intracranial Hemodynamics

   • Albrecht G. Harders

   Pages 32-34

10. Natural Time Course of Vasospasm

    • Albrecht G. Harders

    Pages 35-39

11. Vasospasm and Aneurysm Surgery Within 72 Hours After Subarachnoid Hemorrhage

    • Albrecht G. Harders

    Pages 40-64

12. Correlation of Angiographically Confirmed Vasospasm and Stenosis with Transcranial Doppler

    • Albrecht G. Harders

    Pages 65-69

13. Vasospasm and Delayed Aneurysm Surgery

    • Albrecht G. Harders

    Pages 70-71

14. Intra-aneurysmal Flow Pattern

    • Albrecht G. Harders

    Pages 72-77

15. Extracranial-intracranial Bypass

    • Albrecht G. Harders

    Pages 78-93

16. Arteriovenous Malformations

    • Albrecht G. Harders

    Pages 94-107

17. Monitoring of Frequency Spectra in the MCA During Angiography

    • Albrecht G. Harders

    Pages 108-110

18. Vascular Hemodynamic Response to Meningitis

    • Albrecht G. Harders

    Pages 111-114

19. Brain Death and TCD Recordings

    • Albrecht G. Harders

    Pages 115-118

20. Back Matter

    Pages 119-136

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In 1981, the Norwegian physiologist and cyberneticist, Rune Aaslid, developed a device which made it possible to apply the transcranial Doppler sonographic technique in man. In 1983, Dr. Albrecht Harders took on the project of working out a clinically practicable method that would allow atraumatic measurements to be made of the blood flow velocity in the large branches ofthe circle of Willis. The technique has now become a competitor of the conventional methods of measuring the intracranial hemodynamics, including angiography and the xenon method of cerebral blood flow measurement. Harders proceeded from the assumption that the measurement of the blood flow velocity is more relevant for clinical diagnoses than the usual volume flow measurements. He stresses the very valuable application of the technique in detecting cerebral vasospasm before and after aneurysm surgery. The changes in the blood flow velocities measured by transcranial Doppler sonography in the individual vessel segments of the circle of Willis are interpreted with respect to the various factors that can effect such changes (collateral circulation in the circle of Willis, diameter of the vessel, vascular resistance, the general cardiovascular situation, arterial partial CO pressure, autoregulatory factors, position of body). The rate of 2 complications associated with angiography has thus been reduced, since the best time both for angiography and for surgery can be determined, and continuous TCD examinations show when the patient is out of a critical phase of cerebral vasospasm.

• Bypass
• aneurysm
• angiography
• arteries
• brain
• hemodynamics
• sonography
• surgery
• ultrasound
• Ultrasonography

• Neurochirurgische Universitätsklinik Freiburg i. Br., Federal Republic of Germany

  Albrecht G. Harders

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