Duplex scanning: the second sight of the vascular surgeon
| Autor: | Andrew N. Nicolaides, S.C. Renton |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
medicine.medical_specialty
Blood velocity medicine.diagnostic_test business.industry Ultrasound Vascular surgery Duplex scanning Regional Blood Flow Angiography medicine Venous reflux Carotid bifurcation Humans Ultrasonic sensor Radiology Cardiology and Cardiovascular Medicine business Vascular Surgical Procedures Blood Flow Velocity Biomedical engineering Ultrasonography |
| Zdroj: | European journal of vascular surgery. 4(5) |
| ISSN: | 0950-821X |
| Popis: | Vascular surgery owes a great deal to angiography for its development in the 1950s. Without angiography, the vascular surgeon was as "blind as a mole". 1 In the 1960s it became clear that angiography could only provide anatomical information and vascular surgeons began to demand objective functional data. This was the catalyst for the development of a number of isotope clearance and plethysmographic techniques to meet this need. The 1970s saw the development of two important ultrasonic techniques, namely continuous wave Doppler and B-mode imaging. Continuous wave Doppler ultrasound enabled us to obtain ankle pressures, blood velocity wave forms and to test for venous reflux, but it had two major drawbacks. Firstly, it insonated all tissues and provided simultaneous superimposed signals from all vessels in its path. Secondly, the angle between probe and vessel could not be determined and thus the conversion of Doppler velocity into absolute units (cm/s) was not possible. At that time the introduction of ultrasound imaging provided us with the ability to diagnose and measure the size of aneurysms, but it suffered from the same constraints as angiography. 2 Eventually "gated" Doppler ultrasound was combined with ultrasonic imaging and a powerful tool was developed: duplex scanning. This provided us with the ability to position the beam and sample volume (sampling area) of Doppler ultrasound into an anatomically identifiable vessel and obtain recordings of blood velocity from that vessel only. In addition, because the angle of insonation was known, the velocity could be calculated in absolute units (cm/s). 3 Initially, duplex scanning was used in the diagnosis and grading of carotid bifurcation disease. 4 Now |
| Databáze: | OpenAIRE |
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