Norrving B, Cronqvist S
Acta Neurol Scand. 1981 Oct;64(4):241-52. doi: 10.1111/j.1600-0404.1981.tb04403.x.
The ability of Doppler ultrasound to detect extracranial carotid arterial disease was evaluated in 148 carotid arteries, examined also angiographically. A continuous wave, directional Doppler with zero-crossing meter was used. Doppler diagnosis was based on direct examination of the carotid bifurcation. Of four quantitative variables evaluated, only the end-diastolic ICA/CCA frequency ratio was found to be useful. In stenoses exceeding 75% a deranged Doppler recording was obtained. For stenoses greater than 50% or occlusion sensitivity was 98.3%, specificity 96.6% and over-all accuracy 97.3% with the direct examination technique. Corresponding figures for an indirect Doppler test (frontal artery flow) were 45.8%, 100% and 78.4%. Stenoses less than 50% could not be separated from normal vessels. Direct Doppler examination with a zero-crossing detector is reliable, provided that the limitations of the frequency analysis are considered.
在148条颈动脉中评估了多普勒超声检测颅外颈动脉疾病的能力，这些颈动脉也进行了血管造影检查。使用了带有过零检测器的连续波定向多普勒。多普勒诊断基于对颈动脉分叉的直接检查。在评估的四个定量变量中，仅发现舒张末期颈内动脉/颈总动脉频率比有用。在超过75%的狭窄中，获得了紊乱的多普勒记录。对于大于50%的狭窄或闭塞，直接检查技术的敏感性为98.3%，特异性为96.6%，总体准确率为97.3%。间接多普勒试验（额动脉血流）的相应数字分别为45.8%、100%和78.4%。小于50%的狭窄无法与正常血管区分开来。如果考虑频率分析的局限性，使用过零检测器进行直接多普勒检查是可靠的。
