Annals of Vascular Surgery

, Volume 1, Issue 1, pp 105–111 | Cite as

Detection of stenoses in the internal carotid artery by waveform analysis of continuous wave ultrasound signals (II)

  • William F. Tait
  • David Charlesworth
Original Articles


Analysis of the morphological aspects of continuous-wave Doppler examination is a reliable means of detecting carotid stenosis involving 50% or more of the diameter of the arterial lumen. This study was undertaken to evaluate the indexes likely to increase the diagnostic accuracy of this noninvasive investigation method. The indexes studied were the variations of the maximal frequency and the systolic peak frequencies, measured proximal to and at the level of stenosis, and the ratio of the systolic peak frequency measured in the internal carotid artery and in the common carotid artery. After obtaining data on an experimental model, the study was conducted in healthy volunteers (n=24) and in patients with carotid atherosclerotic disease (n=23). The experimental study confirmed that stenosis greater than 50% leads to a reduction of blood flow and that there is a mathematical relationship between the frequency measured proximal to and at the level of the stenosis and the degree of stenosis. Clinical data showed that there was a significant decrease in the frequency of the systolic peak in elderly «healthy» subjects as compared with younger subjects. However there was no difference between patients with and without stenosis. The index was 0.8 in young subjects, 1.3 in healthy elderly subjects, and greater than 1.3 in subjects who had a stenosis. There was no statistically significant difference between these two last groups. At the threshold value of 2.3, the sensitivity of the Fl index was 22% and the specificity wss 94% in the detection of carotid artery stenosis. In the assessment of the tight stenosis, sensitivity was 44%. In patients considered to be normal after study of the frequency of systolic peak only, the index FI was able to screen patients with carotid stenosis with a sensitivity of 17% and a specificity of 97% and in patients with severe stenosis the sensitivity was 57%. In conclusion, measurements of the maxima frequency or the frequency of systolic peak are unable to increase the accuracy of diagnosis in the detection of stenosis of 50% or less in the carotid bifurcation. The Fl index is a reliable measurement when stenosis is greater than 50%.


Carotid artery stenosis Continuous Doppler, waveform analysis 

Deteccion de estenosis de la arteria carótidea interna mediante el análisis de ondas doppler contínuo (II)


Con este trabajo se pretende averiguar si hay parámetros que obtenidos mediante el Doppler contínuo fuesen capaces de mejorar la exactitud del diagnóstico. Los parámetros seleccionados son los siguientes: 1) variación máxima de frecuencia Doppler (F. max); 2) variación de la máxima velocidad sistólica (max.A) y; 3) exactitud del índice que compara la max.A en la carótida interna y la primitiva (FI). Para ello se construye un modelo experimental con un tubo de silastic lo más similar posible a las características hemodinámicas de la carótida interna. Se simularon estenosis de distintos diámetros como se muestra en la figura 1. A 54 enfermos se les estudió la carótida primitiva interna y externa, así como también la bifurcación carotídea. Estos enfermos se dividieron en los siguientes subgrupos: grupo I, pacientes jóvenes normales; grupo II, pacientes de edad más avanzada (55 años) sin lesiones objectivables; grupo III, estenosis moderada menor del 50% (medición peroperatoria); grupo IV, estenosis severas más del 50 %; grupo V, todas las estenosis (grupos III y IV juntos) y grupo VI, enfermos de los grupos III y IV en los que el valor max. A no es superior a 3.5 kHz. Un tercer estudio determinó el FI en ambos lados en los 57 enfermos con sospecha de lesión carotídea, siendo ésta dividida en menor y mayor del 50%. Del estudio I se deduce que el aumento del valor de F.max fue directamente proporcional a la severidad de la estenosis. En el estudio II hubo una caída significativa del valor medio de max.A en la carótida primitiva proximal en el grupo II comparado con el grupo I (p=0,0003). Del estudio III se puede comprobar que la sensibilidad del FI fue baja, aumentando con la severidad de las lesions. En aquellos pacientes que no fueron detectados usando el valor max.A, la adición del FI aumentó la exactitud diagnóstica, pero sólo en enfermos con lesiones severas. Combinando los valores de max.A 3.5 kHz y un valor FI 2.3, se obtuvo una especificidad del 79% y una sensibilidad para lesiones severas del 83%. Del modelo experimental, se deduce que el comportamiento de la velocidad máxima para cada estenosis está estrechamente relacionado con el de la velocidad media, al menos hasta una reducción del diámetro del 50%. La causa de la baja sensibilidad del valor DFI, reside en la variabilidad del valor FI, en la variabilidad de la edad y del ángulo del haz ultrasónico. Por el contrario, el hecho del aumento importante del valor FI en la severidad de la estenosis, hace este valor muy fiable para estenosis severas.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    TAIT W.F., CHARLESWORTH D. — Detection of stenosis in the internal carotid artery using continuous wave ultrasound I..Ann Chir Vasc, 1986,1, 98–104.Google Scholar
  2. 2.
    MALONE J.M., BEAN B.B., LAGUNA J. et al.— Diagnosis of carotid artery status. Comparison of oculoplethysmography and Doppler supra-orbital examination.Ann Surg, 1980,191, 247–254.CrossRefGoogle Scholar
  3. 3.
    KEAGY B.A., PHARR W.F., THOMAS D.D., BOWES B. E. — Oculoplethysmography/carotid phonoangiography.Arch Surg, 1980,115, 1199–1202.PubMedGoogle Scholar
  4. 4.
    CHAPMAN B.L.Y. — Phonoangiography: the clinical significance and origin of sounds in the carotid arteries. PhD Thesis, Univ Manchester, 1981.Google Scholar
  5. 5.
    APPLEBERG M., CHAMBERS J.L., LANE R. — A comparison of non invasive methods in the assessment of extracranial carotid artery disease.Aust NZ J Surg, 1982,52, 258–264.Google Scholar
  6. 6.
    BASKETT J.J., BEASLEY M.G., MURPHY G.J. et al. — Screening for carotid junction disease by spectral analysis of Doppler signals.Cardiovasc Res, 1977,11, 147–155.PubMedCrossRefGoogle Scholar
  7. 7.
    O'LEARY D.H., PERSSON A.V., CLOUSE M.E. — Non Invasive Testing for Carotid Artery Stenosis. Prospective Analysis of Three Methods.AJR, 1981,137, 1189–1194.PubMedGoogle Scholar
  8. 8.
    PADAYACHEE T.S., LEWIS R.R., GOSLING R.G. — Detection of carotid bifurcation disease: comparison of ultrasound tests with angiography.Br J Surg, 1982,69, 218–222.PubMedCrossRefGoogle Scholar
  9. 9.
    BARNES R.W., RITTGERS S.E., PUTNEY W.W. — Real time Doppler spectral analysis. Predictive value in definign operable carotid artery disease.Arch Surg, 1982,117, 52–57.PubMedGoogle Scholar
  10. 10.
    ZBARNIKOVA V., AKESSON J.A., LASSVIK, C. — Diagnosis of carotid artery disease. Comparison between directional Doppler, duplex scanner and angiography.Acta Neurol Scand, 1982,65, 335–346.Google Scholar
  11. 11.
    BERGUER R., HWANG N.H.C. — Critical arterial stenosis: a theoretical and experimental solution.Ann Surg, 1974,180, 39–50.PubMedCrossRefGoogle Scholar
  12. 12.
    BLACKSHEAR W.M., PHILLIPS D.J., CHIKOS P.M. et al. — Carotid artery velocity patterns in normal and stenotic vessels.Stroke, 1980,11, 67–71.PubMedGoogle Scholar
  13. 13.
    KLIMACH O., CHAPMAN B.L.W., UNDERWOOD C.J., CHARLESWORTH D. — An investigation into how the geometry of an end-to-side arterial anastomosis affects its function.Br J Surg, 1984,71, 43–45.PubMedCrossRefGoogle Scholar
  14. 14.
    RILES T.S., LIEBERMAN A., KOPELMAN I., IMPARATO A.M. — Symptoms, stenosis and bruit. Interrelationships in carotid artery disease.Arch Surg, 1981,116, 218–220.PubMedGoogle Scholar
  15. 15.
    FELL G., PHILLIPS D.J., CHIKOS P.M. et al. — Ultrasonic duplex scanning for disease of the carotid artery.Circulation, 1981,64, 1191–1195.PubMedGoogle Scholar
  16. 16.
    WEAR R.G., HOWARD G., McKINNEY W.M. et al. — Comparison of Doppler ultrasonography with arteriography of the internal carotid artery bifurcation.Stroke, 1980,11, 402–404.Google Scholar
  17. 17.
    KNOX R.A., BRESLAU P.J., STRANDNESS D.E. — A simple parameter for accurate detection of severe carotid disease.Br J Surg, 1982,69, 230–233.PubMedCrossRefGoogle Scholar
  18. 18.
    McNEIL B.J., KEELER E., ADELSTEIN S.J. — Primer on certain elements of medical decision making.New Engl J Med. 1975,293, 211–215.PubMedCrossRefGoogle Scholar
  19. 19.
    BROWN P.M., JOHNSTON K.W., DOUVILLE Y. — Detection of occlusive disease of the carotid artery with continuous wave Doppler spectral analysis.Surg Gynecol. Obstet, 1982,155, 183–186.PubMedGoogle Scholar
  20. 20.
    CRAWFORD E.S., DEBAKEY M.E., BLAISDELL F.W. et al. — Haemodynamic alterations in patients with cerebral arterial insufficiency before and after operation.Surgery, 1960,48, 76–94.PubMedGoogle Scholar
  21. 21.
    MAY A.G., VAN DE BERG L., DEWEESE J.A., ROB C.G. — Critical arterial stenosis.Surgery 1963,54, 250–258.PubMedGoogle Scholar

Copyright information

© Annals of Vascular Surgery Inc 1986

Authors and Affiliations

  • William F. Tait
    • 1
  • David Charlesworth
    • 1
  1. 1.University Department of SurgeryUniversity Hospital of South ManchesterUK

Personalised recommendations