Internal Carotid Artery Doppler Research Articles

Simultaneous Venous-Arterial Doppler Ultrasound During Early Fluid Resuscitation to Characterize a Novel Doppler Starling Curve: A Prospective Observational Pilot Study.

Background: The likelihood of a patient being preload responsive-a state where the cardiac output or stroke volume (SV) increases significantly in response to preload-depends on both cardiac filling and function. This relationship is described by the canonical Frank-Starling curve. Research Question: We hypothesize that a novel method for phenotyping hypoperfused patients (ie, the "Doppler Starling curve") using synchronously measured jugular venous Doppler as a marker of central venous pressure (CVP) and corrected flow time of the carotid artery (ccFT) as a surrogate for SV will refine the pretest probability of preload responsiveness/unresponsiveness. Study Design and Methods: We retrospectively analyzed a prospectively collected convenience sample of hypoperfused adult emergency department (ED) patients. Doppler measurements were obtained before and during a preload challenge using a wireless, wearable Doppler ultrasound system. Based on internal jugular and carotid artery Doppler surrogates of CVP and SV, respectively, we placed hemodynamic assessments into quadrants (Qx) prior to preload augmentation: low CVP with normal SV (Q1), high CVP and normal SV (Q2), low CVP and low SV (Q3) and high CVP and low SV (Q4). The proportion of preload responsive and unresponsive assessments in each quadrant was calculated based on the maximal change in ccFT (ccFTΔ) during either a passive leg raise or rapid fluid challenge. Results: We analyzed 41 patients (68 hemodynamic assessments) between February and April 2021. The prevalence of each phenotype was: 15 (22%) in Q1, 8 (12%) in Q2, 39 (57%) in Q3, and 6 (9%) in Q4. Preload unresponsiveness rates were: Q1, 20%; Q2, 50%; Q3, 33%, and Q4, 67%. Interpretation: Even fluid naïve ED patients with sonographic estimates of low CVP have high rates of fluid unresponsiveness, making dynamic testing valuable to prevent ineffective IVF administration.

Evaluation of carotid artery Doppler measurements in late-onset fetal growth restriction: a cross-sectional study

Background/Aim: It has been reported that both the internal carotid artery (ICA) and the common carotid artery (CCA) are associated with hypoxia, also observed in late-onset fetal growth restriction (FGR). However, it has not yet been investigated whether these Doppler measurements differ in cases of late-onset FGR. This study evaluated the ICA and the CCA Doppler parameters in late-onset FGR fetuses and compared these measurements with those of healthy fetuses. Methods: This cross-sectional observational study comprised 75 singleton pregnancies diagnosed with late-onset FGR between the 32nd and 37th weeks of gestation, alongside 75 healthy fetuses paired 1:1 based on obstetric history and gestational age between June 2022 and May 2023. The Delphi consensus of 2016 was used for the definition of late-onset FGR. The exclusion criteria were congenital anomalies, presence of any additional disease, maternal body mass index over 35 kg/m2, abdominal scars hindering ultrasound visualization, use of medications such as antenatal steroids, sympathomimetics, and indomethacin that affect vascular function, drug use, smoking during pregnancy, concurrent preeclampsia, and multiple pregnancies. Upon the patients' admission to the hospital, their demographic characteristics were documented, and ultrasonographic examinations and Doppler measurements were subsequently performed. The Doppler velocimetry of the umbilical artery (UA) encompassed measurements of the systolic to diastolic ratio (S/D), pulsatility index (PI), and peak systolic velocity (PSV). The carotid artery Doppler velocimetry of the middle cerebral artery (MCA), ICA, and CCA encompassed measurements of the PI, resistance index (RI), and PSV. We assessed the diagnostic performance of Doppler measurements for late-onset FGR through receiver operating characteristic (ROC) analysis. Results: In the late-onset FGR group, the mean UA-SD was higher (2.7 [0.6] vs. 2.5 [0.5], P=0.006), and the mean UA-PI (0.8 [0.2] vs. 0.9 [0.2], P=0.011) and mean PSV (35.6 [8.2] vs. 41.1 [7.1], P<0.001) were lower compared to the control group. In the late-onset FGR group, carotid Doppler measurements were more pronounced than UA Doppler measurements. Moreover, ICA Doppler measurements exhibited superior diagnostic performance in predicting late-onset FGR compared to other Doppler measurements (Area under the curve [AUC]=0.777, P<0.001 for ICA-PI; AUC=0.751, P<0.001 for ICA-RI; AUC=0.749, P<0.001 for ICA-PSV). Conclusion: In fetuses with late-onset FGR, UA Doppler measurements showed minimal differences compared to healthy fetuses, but differences in carotid Doppler measurements, especially in the ICA, were more pronounced. Therefore, in the management of fetuses suspected of having late-onset FGR, a more detailed Doppler examination might be required.

Effect of Internal Carotid Artery Doppler Peak-Systolic Velocity Thresholds for Classifying Ipsilateral Ischemic Stroke Due to Large Artery Atherosclerosis According to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) System for CME Credit September 2023

Effect of Internal Carotid Artery Doppler Peak-Systolic Velocity Thresholds for Classifying Ipsilateral Ischemic Stroke Due to Large Artery Atherosclerosis According to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) System for CME Credit September 2023

Effect of Internal Carotid Artery Doppler Peak Systolic Velocity Thresholds for Classifying Ipsilateral Ischemic Stroke Due to Large Artery Atherosclerosis According to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) System

Background: A Doppler peak systolic velocity (PSV) of 125 cm/s has been used to indicate an internal carotid artery 50% stenosis, a marker of large artery atherosclerosis (LAA) when classifying ischemic stroke according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST). Shifting this cut point to 180 cm/s might affect the classification of ischemic stroke. Methods: Color Doppler–assisted measurements of PSV were performed at the baseline visit of a large longitudinal cohort study in the United States: the Cardiovascular Health Study (CHS). Incident ischemic stroke within the following 6 years was ascertained by adjudicated review of medical records. The side of ischemic stroke was recorded. Incidence rates and odds ratios (logistic regression models) were estimated at the respective 125 cm/s and 180 cm/s cut points. Results: Mean age was 72.8 years with 57.6% women. A total of 11 425 bifurcations had PSV measurements. Of the 514 carotid bifurcations with PSV above 125 cm/s, 20 ipsilateral incident strokes were seen, whereas 6 strokes occurred among the 126 bifurcations with PSV above 180 cm/s. Shifting the cut point decreased categorizing ischemic stroke as due to LAA by 70% (14/20). The odds ratio (1.75; 95% confidence interval, 1.01-3.02) of incident stroke for a PSV between 125 cm/s and 180 cm/s was significant ( P < .05) when compared with a PSV <125 cm/s. Conclusion: Shifting the PSV cut point for a 50% carotid stenosis from 125 cm/s to 180 cm/s would have significant implications when categorizing ischemic stroke as being associated with LAA.

Value of internal juguler vein distensability and carotid artery Doppler in assessment of fluid responsiveness in sever sepsis and septic shock patients

Value of internal juguler vein distensability and carotid artery Doppler in assessment of fluid responsiveness in sever sepsis and septic shock patients

Changes in Internal Carotid Artery Doppler Velocity Measurements With Different Angles of Insonation: A Pilot Study.

Doppler velocity measurements are fundamental diagnostic criteria for vascular ultrasound examinations. Insonation angles are kept to 60° or less to minimize error. The purpose of this study was to assess variance of Doppler-detected peak systolic velocity (PSV) measurements in the internal carotid arteries at different angles (45°, 50°, 55°, and 60°) with different beam steering. The PSV was recorded from the right and left internal carotid arteries in 22 asymptomatic volunteers with straight vessels (total of 44 vessels). A standardized approach was used for recording velocities with the Doppler cursor center steered and steered 15° from right to left. An analysis of variance was performed. The PSV varied significantly with the 4 different angles of insonation (P < .01). The maximum variation between 45° and 60° angles within a single vessel was 29 cm/s. The average variation over the 4 angles was 14 ± 6 cm/s. Relative to the calculated mean velocity for all patients, the standard deviation for the PSV at 60° was nearly twice that recorded at 50° (7.9 versus 3.9). The best correlation of the calculated mean velocity for all patients existed between the angles of 45° and 50° [r(36) = 0.92; P < .001 for center-steered data; and r(40) = 0.96; P < .001 for right-steered data]. These results indicate a statistically significant difference in the PSV measurements taken at varying Doppler angles. The greatest mean, variance, and lowest correlations all result when using 60°. The findings support the need for consistent ultrasound techniques and suggest that further study is warranted regarding the optimal Doppler angle for velocity measurements.

Diagnostic Accuracy of Carotid Doppler Ultrasound for the Detection of Right-to-Left Cardiac Shunt.

Background:Right-to-left cardiac shunt is a condition anatomically related to patent foramen ovale (PFO) and potentially related to cryptogenic cerebrovascular events. As recent studies demonstrated a reduction of recurrent stroke in patients undergoing percutaneous PFO closure after a cryptogenic cerebrovascular event, it is now of pivotal importance to screen these patients for Right-to-left shunt(RLS) presence. At this regard, transcranial color Doppler (TCCD) with contrast has a good sensitivity (97%) and specificity (93%) compared to transesophageal echocardiography and became the test of choice to assess RLS presence, thanks to its noninvasive nature. However, temporal bone window is not accessible in 6%–20% patients. Several approaches have been explored to overcome this limitation with encouraging but not definitive results for extracranial internal carotid artery (ICA) approach, proposed in previous pivotal studies. Aims of this study were to further assess the diagnostic accuracy of ICA Doppler ultrasound with contrast for RLS detection compared to TCCD, with the two tests performed simultaneously.Materials and Methods:Sixty-four patients underwent simultaneously to TCCD and ICA Doppler ultrasound, both performed at rest and after Valsalva maneuver. Diagnosis of RLS was made, both for TCCD and ICA ultrasound, if=1 microembolic signals (MES) were detected during the examination (either at rest or after Valsalva maneuver).Results:ICA Doppler ultrasound sensitivity and specificity resulted respectively of 97% (confidence interval [CI] 95%) and 100% ([CI] 95%), while negative likelihood ratio was 0.03 (CI 95%).Conclusions:ICA Doppler ultrasound represents a valid alternative to TCCD for RLS screening in patients without adequate transcranial acoustic window.

Common Carotid, Internal Carotid and Vertebral Artery Doppler Ultrasonography Findings in Patients With Crimean-Congo Haemorrhagic Fever

Common Carotid, Internal Carotid and Vertebral Artery Doppler Ultrasonography Findings in Patients With Crimean-Congo Haemorrhagic Fever

Correlation of Ocular Pulse Amplitude, Choroidal Thickness, and Internal Carotid Artery Doppler Ultrasound Findings in Normal Eyes

ABSTRACTIntroduction: The choroid receives about 65–85% of ocular blood flow, which comes from the ophthalmic artery (OA), the first branch of the internal carotid artery (ICA). In the foveal avascular zone, there is no retinal vascular supply; therefore, choroidal blood supply plays a significant role in this subfoveal region. The ocular pulse amplitude (OPA) provides useful information about intraocular blood flow and is an indirect indicator of choroidal perfusion. In this study, we aimed to assess the correlation between the OPA, subfoveal choroidal thickness (CT), and ICA Doppler ultrasound findings in healthy eyes. Methods: In total, 48 eyes of 48 healthy volunteers were included in this study. All eyes underwent detailed ophthalmic evaluation, including slit-lamp biomicroscopy, fundus examination, axial length, OPA measurements, and optical coherence tomography (OCT) with enhanced depth imaging mode. Carotid Doppler ultrasound examination was performed by the radiologist. The correlation between the OPA, subfoveal CT, and ICA Doppler findings [peak systolic velocity (PSV) and end-diastolic velocity (EDV)] were evaluated, considering gender and age. Results: The mean OPA was 3.06 ± 1.34 mmHg. The mean subfoveal CT was 305.85 ± 33.98 µm. The mean PSV and EDV of ICA were 73.25 ± 23.63 cm/s and 26.93 ± 13.42 cm/s, respectively. A moderate positive correlation was found between OPA and subfoveal CT (p = 0.001; rho = 0.481). This relationship was present in both men and women. While a positive correlation was found between the OPA and subfoveal CT in subjects under the age of 50 years, there was no correlation in those over the age of 50 years. Conclusions: A fair correlation was found between the OPA and subfoveal CT in healthy subjects under the age of 50.

Temporal and spectral analysis of internal carotid artery Doppler signal for normal and abnormal flow detection.

Detection of carotid artery stenosis is presently highly dependent on ultrasound imaging systems. This work presents a method that can detect the normal and abnormal blood flow in the carotid structure independent of Doppler angle by analysing the time and spectral domain representation of Doppler signal. In the proposed approach, time and spectral domain based features are extracted from the Doppler signals of internal carotid arteries. Further, these features are used in supervised machine learning approach to identify the presence of abnormal blood flow. The proposed method is evaluated on 100 subjects (200 signals) with equal number of normal and abnormal flow profiles. Experimental results show that the maximum classification accuracies of 79.3% and 82.9% are observed with k-nearest neighbours and support vector machine classifiers, respectively.

Choroidal thickness and retinal vascular caliber correlations with internal carotid artery Doppler variables.

Decreased retinal arteriolar caliber and increased retinal venular caliber have been associated with increased cardiovascular mortality. This study aimed to evaluate correlations of choroidal thickness and retinal vascular caliber measurements with internal carotid artery (ICA) Doppler ultrasound variables. In this cross-sectional and observational study, 43 eyes and ICAs of 43 healthy volunteers were examined. Spectral domain optical coherence tomography was used to measure subfoveal choroidal thickness (SFCT) and retinal vascular caliber. The ICA Doppler ultrasonographic parameters were diameter, flow volume, peak-systolic velocity, end-diastolic velocity, resistance index (RI), and pulsatility index (PI). Negative correlations emerged between ICA RI and SFCT (p = 0.017, r = -0.36) as well as between ICA PI and retinal arteriolar caliber (p = 0.015, r = -0.37). A negative linear correlation appeared between ICA diameter and SFCT (p = 0.005, r = -0.42), although ICA diameter and flow volume showed no association with retinal vessel caliber (p > 0.05). Choroidal thickness is negatively correlated with ICA diameter and ICA RI, while retinal arteriolar caliber is inversely related with ICA PI in normal volunteers.

Carotid ultrasound pulsatility indices and cardiovascular risk in Australian women.

Ultrasound-acquired internal carotid arterial (ICA) pulsatility indices (PI) have been demonstrated to be useful measures of cerebrovascular disease. The purpose of this cross-sectional study was to investigate the association between carotid artery PI, cardiovascular risk and ischaemic heart disease in aging women. One hundred and fifty-eight female participants of the Longitudinal Assessment of Ageing in Women study, aged 48-85 years, were evaluated. The relationships between common carotid artery (CCA) and ICA Doppler PI to cardiovascular risk factors (age, body mass index, systolic and mean arterial blood pressure, smoking and diabetes), carotid-femoral (femPWV) and carotid-radial (radPWV) pulse wave velocities, and ischaemic heart disease (IHD) were assessed using Spearman's rank correlation (ρ), multiple regression and logistic regression. Dependent variables were Box-Cox transformed to meet linear regression assumptions. CCA and ICA PI were significantly correlated to femPWV (ρ = 0.414 and ρ = 0.544, respectively). Cardiovascular risk factors were significantly predictive of CCA PI (Adj R(2) = 0.176, P < 0.01); however, their relationship to ICA PI (Adj R(2) = 0.508, P < 0.01) was stronger. This result was comparable with the relationship between cardiovascular risk factors and femPWV (Adj R(2) = 0.561, P < 0.01). Age and systolic blood pressure were the dominant risk factors for IHD in this group. ICA PI is comparable with femPWV in its association with cardiovascular disease. PI does not improve the prediction of IHD over age and systolic blood pressure.

Childhood cognitive development after fetal growth restriction

To examine the relationship between prenatal umbilical artery (UA) and internal carotid artery (ICA) Doppler findings and cognitive development at 3 and 6 years in low-birth-weight children. This was a study of 209 low-birth-weight (< 10(th) centile) children born after 28 gestational weeks with UA resistance index (RI) measured within 2 weeks before delivery. Children with normal UA- and ICA-RI were defined as small-for-gestational age (SGA) and those with abnormal UA or ICA Doppler findings as having fetal growth restriction (FGR). Cognitive ability at 3 and 6 years' corrected age was assessed using the fourth edition of the Stanford-Binet Intelligence Scale (SBIS) and compared between SGA and FGR groups. An SBIS score < 85 was considered to indicate delayed development. The median gestational age at diagnosis of abnormal fetal growth was 36.6 (range, 28-41) weeks. There were 87 (41.6%) children classified as having FGR and 122 (58.4%) as SGA. The mean global SBIS score at 3 years was 109.4 (SD, 22.8) and at 6 years it was 110.5 (SD, 13.9). Overall, 22 (10.5%) children had delayed development at 3 years. Total SBIS scores and individual domain scores did not differ between FGR and SGA groups at 3 or 6 years and similar proportions in each group had delayed development. Abnormal prenatal UA and ICA Doppler findings are not associated with lower developmental scores in low-birth-weight children delivered in the third trimester of pregnancy.

Classification of internal carotid artery Doppler signals using fuzzy discrete hidden Markov model

We developed a biomedical system based on Discrete Hidden Markov Model (DHMM). The aim of our system is to classify the internal carotid artery Doppler signals. We applied a fuzzy approach to DHMM. Thus we decreased information loss and increased the classification performance. Our system reached 97.38% of classification accuracy with 5 fold cross validation. These results showed that the Fuzzy Discrete Hidden Markov Model (FDHMM) method is effective for classification of internal carotid artery Doppler signals.

Biomedical system based on the Discrete Hidden Markov Model using the Rocchio–Genetic approach for the classification of internal carotid artery Doppler signals

When the maximum likelihood approach (ML) is used during the calculation of the Discrete Hidden Markov Model (DHMM) parameters, DHMM parameters of the each class are only calculated using the training samples (positive training samples) of the same class. The training samples (negative training samples) not belonging to that class are not used in the calculation of DHMM model parameters. With the aim of supplying that deficiency, by involving the training samples of all classes in calculating processes, a Rocchio algorithm based approach is suggested. During the calculation period, in order to determine the most appropriate values of parameters for adjusting the relative effect of the positive and negative training samples, a Genetic algorithm is used as an optimization technique. The purposed method is used to classify the internal carotid artery Doppler signals recorded from 136 patients as well as of 55 healthy people. Our proposed method reached 97.38% classification accuracy with fivefold cross-validation (CV) technique. The classification results showed that the proposed method was effective for the classification of internal carotid artery Doppler signals.

HYPERCAPNIA-INDUCED CEREBROVASCULAR RESERVE OF YOUNG HYPERTENSIVE PATIENTS: PP.4.150

Objectives: The aim of this study was evaluate state cerebrovascular reactivity in condition of hypercapnia-induced CO2 cerebrovascular reserve at young hypertensive patients. Methods: We used ultasonography of internal carotid artery (ICA) and transcranial Doppler‘s method in the study of middle cerebral arteries (MCA) from temporal window. We studied the changes of flow velocity mean (FVm) and diameter (D) starting, at the time of hypercapnia (inhalation 2 min 4% mixture of carbonic gas (MCG) with air) and FmV in period of recovery (rec) (air-inhalation 3 min) of 21 patients (1group) with essential hypertension with grade I-II and 20 healthy volunteers (2group) without cerebral stroke during of the life history (age 18–25years). Secondary hypertension were excluded by clinical and biochemical tests. At the time of vascular evaluation, none of the patients had a history or clinical evidence of peripheral vascular disease, coagulopathy, or any disease predisposing them to vasculitis. All participants of research have given the informed agreement. We used coefficient of FVm - CFVmCO2 = VmCO2/Vm0, index of D – IDCO2 = (DCO2-D0)/T and index of recovery IVmrecCO2 = Vm0/Vmrec; Vm0 and D0 is starting parameters. VmCO2, DCO2 and T -time is inhalation parameters. Statistical analysis: descriptive, t-test independent by groups. Results: Patients and healthy volunteers had not distinctions of anthropometrical parameters. Significant difference was found between 1 and 2 groups: FVm in ICA 68,3 ± 0,9 and 60,3 ± 1,9 ð < 0,05sm/s; CFVmCO2 - 1,24 ± 0,13 and 1,56 ± 0,21 ð < 0,05; IDCO2 - 0,31 ± 0,04 and 0,52 ± 0,15 ð < 0,05; IVmrecCO2 - 1,14 ± 0,08 and 0,98 ± 0,06 ð < 0,01 respectively. Conclusion: Young patients with a hypertension had higher blood velocity in ICA and inhibited cerebrovascular reactivity and decrease in adequacy of the answer of arterial blood circulation of a brain in condition of hypercapnia.

Detection of Carotid Artery Disease by Using Learning Vector Quantization Neural Network

Doppler ultrasound has been usually preferred for investigation of the artery conditions in the last two decades, because it is a non-invasive, easy to apply and reliable technique. In this study, a biomedical system based on Learning Vector Quantization Neural Network (LVQ NN) has been developed in order to classify the internal carotid artery Doppler signals obtained from the 191 subjects, 136 of them had suffered from internal carotid artery stenosis and rest of them had been healthy subject. The system is composed of feature extraction and classification parts, basically. In the feature extraction stage, power spectral density (PSD) estimates of internal carotid artery Doppler signals were obtained by using Burg autoregressive (AR) spectrum analysis technique in order to obtain medical information. In the classification stage, LVQ NN was used classify features from Burg AR method. In experiments, LVQ NN based method reached 97.91% classification accuracy with 5 fold Cross Validation (CV) technique. In addition, the classification performance of the LVQ NN was compared with some methods such as Multi Layer Perceptron (MLP) NN, Naive Bayes (NB), K-Nearest Neighbor (KNN), decision tree and Support Vector Machine (SVM) with sensitivity and specificity statistical parameters. The classification results showed that the LVQ NN method is effective for classification of internal carotid artery Doppler signals.

Analysis of the Doppler signals using largest Lyapunov exponent and correlation dimension in healthy and stenosed internal carotid artery patients

Nonlinear analysis techniques have been applied for many applications on the physiological systems. In this research, the largest Lyapunov exponent (LLE) and correlation dimension (CD) calculations were performed to evaluate the chaotic behaviour of blood flow obtained from the healthy and stenosed internal carotid artery (ICA) using noninvasive Doppler ultrasonography technique. The Doppler signals were taken from 30 healthy, 8 mild, 8 moderate and 8 serious degree of stenosis ICA subjects. The LLE calculation was performed by using Wolf algorithm. The Grassberger-Procaccia algorithm was used for CD analysis. The calculated LLE and CD values for stenosed ICA Doppler signals were found as significantly high compared to the values belonging to the healthy subjects. It is found that, the LLEs and CDs of stenosed ICA Doppler signals increase with the increasing of the degree of stenosis. The results show that the LLE and CD can be used for diagnosis of the ICA stenosis and to determine the degree of stenosis.

Suspicious Extracranial Duplex Examination: A Predictor of Intracranial Disease?

Introduction Moyamoya disease is a rare and progressive condition with poor long-term prognosis. A meticulous evaluation during an extracranial carotid duplex exam, with attention to subtle changes in anatomy and Doppler signals, can alert the sonographer to pathology in the intracranial circulation, which may suggest this diagnosis. Case Report A 45-year-old woman presented to our vascular lab with an episode of slurred speech, right arm weakness, right-sided numbness, and generalized weakness that lasted 15 – 20 min, with total resolution of symptoms. A carotid duplex examination was ordered and demonstrated no evidence of extracranial carotid disease; however, bilaterally the external carotid artery was larger in size than the internal carotid artery, multiple prominent external carotid artery branches were noted, the internal carotid artery and vertebral artery Doppler signals demonstrated low-resistance waveforms with high diastolic flow velocity, and the left vertebral artery was enlarged. Magnetic resonance imaging with angiography demonstrated multiple intracranial abnormalities, and conventional angiography was compatible with Moyamoya disease. A superficial temporal artery-to-middle cerebral artery bypass was performed with an uneventful postoperative course and no recurrence of symptoms. Conclusions Subtle changes in anatomy and Doppler signals observed during an extracranial carotid duplex examination can be important indicators of pathology in a location that is not under direct visualization and interrogation. It is important for the sonographer to note these changes and report them to the physician for further evaluation by more direct methods of testing. This case provides an example of the use of such indirect sonographic evidence.

Age, Race, and Gender Influence Internal Carotid Artery Doppler Velocities in Children

Introduction Few data are available describing internal carotid artery pulsed-wave Doppler velocities in children. Therefore, mean values were obtained in healthy children and correlates of peak systolic (PSV) and end diastolic (EDV) velocities were determinants. Methods As part of an ongoing longitudinal study of cardiovascular risk factors in children, bilateral PSV and EDV were obtained in 115 subjects (age 17.0 ± 3.8 years; 37% Caucasian, 63% African American; 43% male, 57% female). Standard carotid duplex imaging was performed with a GE Vivid 7, 7–12 MHz linear array transducer. Velocities were acquired in the proximal 2 cm of each artery, placing the angle of insonation parallel to vessel wall resulting in angles of ≥50 degrees and ≤60 degrees. All velocities were measured in triplicate. Means and standard deviations of all significant variables were calculated and differences tested with t-testing. Pearson correlation coefficients between PSV, EDV, and covariates (age &lt; or ≥ 18 years, height (HT), weight (WT), gender, systolic blood pressure) were determined. General linear models were constructed to elucidate significant determinants of velocities. Results Mean values for PSV and EDV differed significantly by age and race. PSV values differed by gender (all p &lt; 0.02). Age and race correlated with PSV and EDV, whereas gender correlated only with PSV measures. In general linear models, when stratified by age groups, age and race were significant determinates of both velocities and HT only a determinate for PSV. Younger subjects had greater velocities. When stratified by race, results were similar, with Caucasians having increased velocities. When stratified by gender, no models were significant. Conclusion Normal PSV and EDV values are greater in children than adults and in Caucasians versus African-Americans. These may be influenced by age and race differences in HT. Proximal internal carotid pulsed Doppler velocities in children should be interpreted based by age and race.