Pulsed Doppler frequency and carotid stenosis

Area of Science:

• Vascular Ultrasound
• Cerebrovascular Disease
• Medical Imaging

Background:

• Internal carotid artery (ICA) stenosis is a significant risk factor for stroke.
• Accurate assessment of stenosis severity is crucial for treatment decisions.
• Non-invasive methods for quantifying ICA stenosis are highly desirable.

Purpose of the Study:

• To evaluate the ability of peak systolic frequency (PSF) derived from pulsed Doppler spectrum analysis to predict the degree of internal carotid stenosis.
• To compare the diagnostic performance of different PSF thresholds for identifying significant stenosis.

Main Methods:

• Two hundred and forty-two internal carotid arteries were analyzed using arteriography and pulsed Doppler spectrum analysis.
• Peak systolic frequency (PSF) was measured and correlated with the degree of diameter reduction.
• Receiver-operator characteristic (ROC) analysis was used to determine optimal PSF cutoffs.

Main Results:

• Mean PSF was significantly higher in high-grade (greater than 50%) ICA stenoses (6.55 kHz) compared to low-grade (less than 50%) stenoses (3.38 kHz) (P < 0.0001).
• PSF thresholds of 4.5 kHz and 5.0 kHz demonstrated high sensitivity and specificity for identifying 50% diameter stenosis.
• Linear and nonlinear regression analyses provided equations to estimate stenosis percentage from PSF, with correlation coefficients (r) of 0.76 and 0.77, respectively.

Conclusions:

• Peak systolic frequency (PSF) measured by pulsed Doppler spectrum analysis is a valuable tool for differentiating high-grade from low-grade internal carotid artery stenoses.
• PSF measurements can precisely quantify the degree of luminal narrowing in the ICA.
• Doppler-derived PSF offers a reliable non-invasive method for assessing carotid artery stenosis severity.