Diagnosis Of Carotid Artery Disease Research Articles

Pulsed multigated Doppler ultrasonography in the diagnosis of carotid artery disease.

To evaluate the accuracy of a pulsed multigated Doppler system, 128 carotid arteries were examined. The spectral broadening index was calculated from the power spectrum of a small sample volume located in the center of the stream according to the flow profile and was related to the degree of stenosis as determined by contrast angiography. Even minor wall irregularities seen on the angiogram were classified as disease. The ability of the system to discriminate between normal and diseased vessels reached a sensitivity of 94% and a specificity of 91%. Classification of greater than 50% or less than 50% stenosis could be performed with a sensitivity of 90% and a specificity of 85%. Pulsed multigated Doppler ultrasonography allows identification of even minor degrees of stenosis of the carotid artery and provides an alternative to duplex scanning. Furthermore, the blood flow profile provided by a multigated Doppler system may add valuable information concerning blood flow characteristics not obtainable by single-gated systems.

Factors affecting the continuous wave Doppler spectrum for the diagnosis of carotid arterial disease

Spectral analysis of continuous wave (CW) Doppler signals is used for the diagnosis of carotid arterial disease. Previous clinical and in vitro studies have documented that the peak Doppler frequency is increased in recordings made directly over a stenosis and that spectral broadening is observed beyond a stenosis in the region of disturbed flow. However, certain hemodynamic and technical factors can effect the Doppler spectrum and in particular cause spectral broadening although they are not related to the severity of the arterial stenosis. In this in vitro study, Doppler spectra were quantified by (1) measurements of the peak, mean and mode frequencies, and (2) measurements that quantify changes in the shape of the spectra and thus can potentially detect the presence of spectral broadening. The latter measurements included the spectral broadening index (SBI), coefficient of variation (CV), coefficient of skewedness (CS), and coefficient of kurtosis (CK). Using straight tubes without a bifurcation in a steady flow model, we found that the peak frequency and the extent of spectral broadening were dependent upon the severity of the stenosis, the relation of the recording site to the stenosis or bulb, and the flow rate. Comparison of the severity of Doppler spectral broadening from bulb and stenosis recordings allowed us to conclude that any observed changes in spectral broadening measurements are probably due to a significant stenosis and not to the presence of a normal bulb. If the tube is not completely insonated by the CW Doppler beam, an error of between 4 and 35% can be read in the spectral broadening measurements. The peak frequency, mean frequency, and SBI are not altered significantly by the automatic gain control or dynamic range and noise level settings usually chosen by the spectrum analyzer. Because of the variability of individual Doppler spectra, one should be cautious about deriving quantitative data from one individual spectrum. The results of quantitative analysis of the amplitude spectrum are different from the power spectrum. In conclusion, this in vitro study identified several hemodynamic and technical factors that affect the CW Doppler spectrum; however, in the clinical setting, their influence on quantitative measurements of the extent of spectral broadening likely can be minimized by a skilled technologist who uses a standardized technique.

Carotid artery disease. A therapeutic enigma.

Many patients with carotid artery disease experience a diversity of ocular symptoms (Table). Thus, the ophthalmologist (1) is often the first physician to see the patient or (2) is asked to act as a consultant to identify structural disease, to confirm or to exclude the presence of retinal emboli, or to perform noninvasive tests reflecting the patency of the carotid circulation. During the past decade, a number of techniques for the diagnosis of carotid artery disease have been developed. There has been a concomitant increase in the number of endarterectomies performed (15000 in 1971 to 103 000 in 1984)2on both symptomatic and asymptomatic patients. This rise has occurred despite little evidence to support the efficacy of the procedure.3-5The majority of endarterectomies fall into the category of prophylactic surgery, in which the patient can be either asymptomatic (ie, patients with neck bruits revealed at routine physical examination)

Accuracy of carotid Doppler peak frequency analysis: Results determined by receiver operating characteristic curves and likelihood ratios

To determine the accuracy of peak Doppler frequency measurements in the diagnosis of extracranial carotid arterial disease and to apply the results to the assessment of the individual patient, 397 studies of continuous-wave Doppler frequency analysis were compared with the results of arteriography. The diagnostic accuracy of the measurement of peak frequency was determined in two ways. First, receiver operator characteristic curves were calculated for different threshold levels of peak frequency. The results showed that the measurement of the peak frequency can be related in only an approximate way to the severity of the arteriographic stenosis because of the uncertainty of the probe-to-vessel angle. Nevertheless, the overall maximum diagnostic accuracy was approximately 91% (Kappa = 0.82 ± 0.05). Second, likelihood ratios were calculated to take into account the degree of abnormality of the peak frequency measurements. The probability of carotid disease increased as the peak frequency increased, giving likelihood ratio ranges from 0.03 to 25.71. To be able to apply the peak frequency measurements to the assessment of the individual patient in the vascular laboratory, our results were used to construct tables that show the posttest probability of carotid disease based on the clinically estimated pretest probability of disease and the measured peak frequency. It is concluded that the measurement of peak Doppler frequency is an adjunct in the diagnosis of carotid artery disease.

In vitro comparison of alternative methods for quantifying the severity of doppler spectral broadening for the diagnosis of carotid arterial occlusive disease

Quantitative analysis of continuous wave Doppler recordings is of clinical value in the noninvasive diagnosis of carotid arterial disease. Peak frequency measurements are useful and accurately detect severe stenoses but do not reliably diagnose minor or moderate stenoses because the measurement is dependent upon the probe to vessel angle, which cannot be measured accurately. Recent investigations have focused on efforts to overcome this limitation by quantifying the degree of spectral broadening that occurs as the result of flow disturbances downstream from a stenosis. In this study, an in vitro model was used to determine the optimum method for quantifying the instantaneous Doppler spectrum. The model generates blood flow velocity waveforms that are virtually identical to those found in the human internal carotid artery. Doppler recordings were made from normal tubes and distal to stenoses (39–87% cross-sectional area reduction). The spectra were quantified by the following angle-independent measurements: spectral broadening index and three standard statistical shape descriptors, namely the coefficients of variation, skewedness and kurtosis. Using this model, the results demonstrate an excellent relationship between the severity of the stenosis and each of spectral broadening index ( r = 0.99), coefficient of variation ( r = 0.96), and coefficient of skewedness ( r = 0.99). The calculation of each of the measurements can be implemented quite easily, and a prospective trial is warranted to evaluate their clinical diagnostic accuracy.

Quantitative estimation of spectral broadening for the diagnosis of carotid arterial disease: Method and in vitro results

For the quantitative assessment of carotid arterial disease using continuous wave Doppler ultrasound, the choice of an index to describe the degree of spectral broadening is important. It is shown that a spectral broadening index (SBI) given by 100(1 − f mean/ f max) and evaluated over a 25 msec period around peak systole is relatively insensitive to artifacts and has potential for achieving good clinical sensitivity. Furthermore, it can be implemented very simply on a microcomputer for on-line display. A description of a microcomputer based system, together with the results obtained using an in vitro flow model that closely approximates the carotid flow velocity waveform, are presented. Results relating the SBI to the degree of stenosis, recording site, and angle of insonation, are given. In addition, the results obtained with a commercial system that computes SBI based on the power spectrum, are presented for comparison.

The contribution of spectral analysis to the diagnosis of carotid artery disease

Pulsed and continuous-wave Doppler examinations with spectral analysis were performed on 258 carotid arteries in 220 patients and compared with multiplane contrast angiography. Each artery was examined for stenosis and assigned to one of four groups: normal to 19%, 20% to 49%, 50% to 99%, and occlusion. The incidence of disease was 70%. Diagnostic sensitivity with all noninvasive techniques varied from 76% to 90% depending on the degree of stenosis, with an overall accuracy rate of 86%. In an attempt to evaluate the diagnostic contribution of spectral analysis, stenosis classification by peak frequency alone was compared with that of the full laboratory profile, including spectral analysis. In the 147 carotid arteries in which such data were available, diagnostic sensitivity was improved with spectral analysis by 8% to 29% depending on the degree of stenosis. Detection of occlusions was unchanged. The major contribution of spectral analysis was in detecting non-flow-limiting stenoses of 20% to 49%. Spectral analysis added little to the diagnostic ability of peak frequency to detect lesions with >50% stenosis. Spectral analysis of either pulsed Doppler or continuous-wave Doppler signals is an accurate noninvasive method for evaluating carotid bifurcation disease, which particularly improves the detection of non-flow-limiting stenoses.

The contribution of spectral analysis to the diagnosis of carotid artery disease.

Pulsed and continuous-wave Doppler examinations with spectral analysis were performed on 258 carotid arteries in 220 patients and compared with multiplane contrast angiography. Each artery was examined for stenosis and assigned to one of four groups: normal to 19%, 20% to 49%, 50% to 99%, and occlusion. The incidence of disease was 70%. Diagnostic sensitivity with all noninvasive techniques varied from 76% to 90% depending on the degree of stenosis, with an overall accuracy rate of 86%. In an attempt to evaluate the diagnostic contribution of spectral analysis, stenosis classification by peak frequency alone was compared with that of the full laboratory profile, including spectral analysis. In the 147 carotid arteries in which such data were available, diagnostic sensitivity was improved with spectral analysis by 8% to 29% depending on the degree of stenosis. Detection of occlusions was unchanged. The major contribution of spectral analysis was in detecting non-flow-limiting stenoses of 20% to 49%. Spectral analysis added little to the diagnostic ability of peak frequency to detect lesions with greater than 50% stenosis. Spectral analysis of either pulsed Doppler or continuous-wave Doppler signals is an accurate noninvasive method for evaluating carotid bifurcation disease, which particularly improves the detection of non-flow-limiting stenoses.

Doppler power frequency spectrum analysis in the diagnosis of carotid artery disease.

Power Frequency Spectral Analysis (PFSA) which evaluates the power of the frequency components at a selected interval, was applied in this preliminary study using a 5MHz Doppler continuous wave flow velocity meter and a modified Edwards Spectraview 500 analyzer. PFSA was used to study the common, internal and external carotid arteries of ten young adult control subjects and 31 patients with angiographically documented carotid bifurcation lesions. Two useful indices are described: (1) the frequency band width at 50% of maximum power (f50%) and (2) the highest frequency recorded (fmax). An f50% wider than 1900 Hz (corresponding to spectrum broadening) identified stenoses as low as a 15% diameter reduction. An fmax higher than 6500 Hz practically always indicated a 50% or greater diameter reduction. Eighty two percent of stenoses with 11-25% diameter reduction were detected, as were 95% of stenoses from 36-50%. All stenoses from 51-99% were identified.

Real-time B-mode carotid imaging: A three-year multicenter experience

This report attempts to establish the place of real-time B-mode carotid imaging in the diagnosis of carotid artery disease through an analysis of the results of 3 years of experience in three major noninvasive vascular laboratories. Over 7000 patients were studied noninvasively with real-time B-mode carotid imaging and oculoplethysmography (OPG). Angiographic comparisons of 1723 vessels form the basis of this study. All tests were interpreted by physicians who had no knowledge of the angiograms. Images and x-ray films were classified by diameter of stenosis: grade I (0% to 39%), grade II (40% to 69%), grade III (70% to 99%), and grade IV (total occlusion). The effect of the imaging experience was determined by dividing the study into two periods. The results of image quality vs. accuracy and of combining the anatomic study (scan) and physiologic study (OPG) were also evaluated. The overall data show a specificity of 87% (985 of 1139), a sensitivity for grade II disease of 72% (193 of 267), a sensitivity for grade III of 66% (133 of 201), and a sensitivity for grade IV of 64% (74 of 116). With experience each center showed improvement of the imaging technique in diagnosing grade III (p > 0.1: not significant) and grade IV disease (p < 0.0002: highly significant), although there was no improvement in the specificity and sensitivity of grade II disease. All scan errors were analyzed. Most errors were interpretation errors (27%: 90 of 338), scan/arteriogram mismatches (23%: 79 of 338), or poor-quality scans secondary to existing disease (22%: 75 of 338). There was a direct correlation of scan quality and accuracy, with a 97% specificity for grade I scans of good to excellent quality. When the scan and OPG agreed, there were uniform predictive values for all grades (88% to 93%). Sixteen of 79 scan/arteriogram mismatch vessels were operated on, and the scan proved more reliable in 86%. Real-time B-mode carotid imaging is a reliable technique for defining the normal carotid artery and is becoming increasingly sensitive in identifying existing disease. Despite its limitations, its strong points make it a valuable clinical tool.

Real-time B-mode carotid imaging. A three-year multicenter experience.

This report attempts to establish the place of real-time B-mode carotid imaging in the diagnosis of carotid artery disease through an analysis of the results of 3 years of experience in three major noninvasive vascular laboratories. Over 7000 patients were studied noninvasively with real-time B-mode carotid imaging and oculoplethysmography (OPG). Angiographic comparisons of 1723 vessels form the basis of this study. All tests were interpreted by physicians who had no knowledge of the angiograms. Images and x-ray films were classified by diameter of stenosis: grade I (0% to 39%), grade II (40% to 69%), grade III (70% to 99%), and grade IV (total occlusion). The effect of the imaging experience was determined by dividing the study into two periods. The results of image quality vs. accuracy and of combining the anatomic study (scan) and physiologic study (OPG) were also evaluated. The overall data show a specificity of 87% (985 of 1139), a sensitivity for grade II disease of 72% (193 of 267), a sensitivity for grade III of 66% (133 of 201), and a sensitivity for grade IV of 64% (74 of 116). With experience each center showed improvement of the imaging technique in diagnosing grade III (p greater than 0.1: not significant) and grade IV disease (p less than 0.0002: highly significant), although there was no improvement in the specificity and sensitivity of grade II disease. All scan errors were analyzed. Most errors were interpretation errors (27%: 90 of 338), scan/arteriogram mismatches (23%: 79 of 338), or poor-quality scans secondary to existing disease (22%: 75 of 338). There was a direct correlation of scan quality and accuracy, with a 97% specificity for grade I scans of good to excellent quality. When the scan and OPG agreed, there were uniform predictive values for all grades (88% to 93%). Sixteen of 79 scan/arteriogram mismatch vessels were operated on, and the scan proved more reliable in 86%. Real-time B-mode carotid imaging is a reliable technique for defining the normal carotid artery and is becoming increasingly sensitive in identifying existing disease. Despite its limitations, its strong points make it a valuable clinical tool.

頚部頚動脈病変のCT診断

頚部頚動脈病変のCT診断

Objective feature extraction applied to the diagnosis of carotid artery disease using a Doppler ultrasound technique

Using the maximum frequency envelope obtained from the sonogram of the Doppler shifted frequencies a mathematical feature extraction technique has been used to provide an objective identification of the significant waveform features. The technique described is that of principal component factor analysis. The data used were taken from an eighteen month programme in which techniques based on the use of directional Doppler ultrasound were evaluated in comparison with direct percutaneous carotid angiography and arch aortography. A tracing of the vessel outlined based on the anterior-posterior view of the angiogram was used to classify each vessel segment studied. Two groups only are considered in this initial study, a normal group (25 vessel segments) and a stenosis group (18 vessel segments). The principal component analysis technique was shown to provide a superior classification of the vessel segments when compared with the more familiar A/B ratio. Nevertheless the principal diagnostic feature is shown to be the A/B ratio.

Noninvasive techniques for diagnosis of carotid artery disease.

HomeStrokeVol. 9, No. 5Noninvasive techniques for diagnosis of carotid artery disease. Free AccessAbstractPDF/EPUBAboutView PDFSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessAbstractPDF/EPUBNoninvasive techniques for diagnosis of carotid artery disease. B A Sandok B A SandokB A Sandok Search for more papers by this author Originally published1 Sep 1978https://doi.org/10.1161/01.STR.9.5.427Stroke. 1978;9:427–429 Previous Back to top Next FiguresReferencesRelatedDetailsCited By Spencer M (1987) Introduction Ultrasonic Diagnosis of Cerebrovascular Disease, 10.1007/978-94-009-4305-6_1, (1-6), . Hennerici M and Freund H (1984) Efficacy of CW-Doppler and Duplex System Examinations for the Evaluation of Extracranial Carotid Disease, Journal of Clinical Ultrasound, 10.1002/jcu.1870120307, 12:3, (155-161), Online publication date: 1-Mar-1984. Alves A, Sterensis J and Alves A (2016) Noninvasive Versus Invasive Evaluation of the Extracranial Circulation in Patients With Suspected Cerebral Vascular Disease, Angiology, 10.1177/000331978303400304, 34:3, (183-191), Online publication date: 1-Mar-1983. Weinstein M, Modic M, Furlan A, Pavlicek W and Little J (1983) Digital substraction angiography in the evaluation of intracranial and extracranial vascular disease, Cardiovascular and Interventional Radiology, 10.1007/BF02552433, 6:4-6, (187-196), Online publication date: 1-Nov-1983. Slade W, Enker S, Borras R and Jia Rhon Chen (2016) The Underlying Problems Resulting in Controversies in the Clinical Management of Transient Ischemic Attacks: An Overview, Angiology, 10.1177/000331978303401002, 34:10, (639-645), Online publication date: 1-Oct-1983. Furlan A, Weinstein M, Little J and Modic M (1983) Digital Subtraction Angiography in the Evaluation of Cerebrovascular Disease, Neurologic Clinics, 10.1016/S0733-8619(18)31171-X, 1:1, (55-72), Online publication date: 1-Feb-1983. CHAN A, BEACH K, LANGLOIS Y, ROEDERER G and STRANDNESS D (1982) EVALUATION OF EXTRACRANIAL CAROTID ARTERY DISEASE BY ULTRASONIC DUPLEX SCANNING: A CLINICAL PERSPECTIVE, ANZ Journal of Surgery, 10.1111/j.1445-2197.1982.tb06112.x, 52:6, (562-569), Online publication date: 1-Dec-1982. Alves A and Sterensis J (2016) Correlation Between Ultrasonic Doppler Arterial Scanning of the Extracranial Circulation and Cerebral Angiography, Vascular Surgery, 10.1177/153857448201600206, 16:2, (106-110), Online publication date: 1-Mar-1982. Adams H (2016) Transient ischemic attacks, Postgraduate Medicine, 10.1080/00325481.1981.11715683, 69:2, (157-166), Online publication date: 1-Feb-1981. Warlow C and Fish P (1980) Pulsed Doppler imaging of the carotid artery, Journal of the Neurological Sciences, 10.1016/S0022-510X(80)80015-3, 45:1, (135-141), Online publication date: 1-Jan-1980. (1980) Cervical Arterial Bruits, New England Journal of Medicine, 10.1056/NEJM198008213030816, 303:8, (460-461), Online publication date: 21-Aug-1980. Davis H, Siegel B, Sherman L, Heaton W, Naidich T, Joist J and Welch M (1980) Scintigraphic detection of carotid atherosclerosis with indium-111-labeled autologous platelets., Circulation, 61:5, (982-988), Online publication date: 1-May-1980.Goran A and Moore G (1980) Value of the non-invasive cerebrovascular laboratory in diagnosis of extracranial carotid artery disease. An analysis of 159 studies in 157 patients., Stroke, 11:4, (325-328), Online publication date: 1-Jul-1980. Frisén L, Lindberg B, Kjällman L and Svendsen P (1979) DETECTION OF EXTRACRANIAL CAROTID STENOSIS BY COMPUTED TOMOGRAPHY, The Lancet, 10.1016/S0140-6736(79)91950-0, 313:8130, (1319-1320), Online publication date: 1-Jun-1979. Spencer M (1979) Non-invasive methods defended as valuable., Stroke, 10.1161/str.10.4.478b, 10:4, (478-478), Online publication date: 1-Jul-1979. Sowers J and McGraw C (1979) Trifluoperazine pretreatment in experimental CI gerbils., Stroke, 10.1161/str.10.4.478a, 10:4, (478-478), Online publication date: 1-Jul-1979. Strandness D (1979) The Use and Abuse of the Vascular Laboratory, Surgical Clinics of North America, 10.1016/S0039-6109(16)41890-6, 59:4, (707-717), Online publication date: 1-Aug-1979. Barnett H (1979) The Pathophysiology of Transient Cerebral Ischemic Attacks: Therapy with Platelet Antiaggregants, Medical Clinics of North America, 10.1016/S0025-7125(16)31667-4, 63:4, (649-679), Online publication date: 1-Jul-1979. Robertson J and Watridge C (1979) The Surgical Management of Extracranial and Intracranial Occlusive Disease, Medical Clinics of North America, 10.1016/S0025-7125(16)31668-6, 63:4, (681-693), Online publication date: 1-Jul-1979. September 1978Vol 9, Issue 5 Advertisement Article InformationMetrics Copyright © 1978 by American Heart Associationhttps://doi.org/10.1161/01.STR.9.5.427 Originally publishedSeptember 1, 1978 PDF download Advertisement

Noninavasive angiography for the diagnosis of carotid artery disease using Doppler ultrasound (carotid artery Doppler).

To detect stenosis in the carotid artery with a bidirectional continuous-wave Doppler ultrasound device, the following noninvasive procedure, applied on 800 patients and compared with 249 angiograms of 186 patients, has proved to be about 90% reliable. Measurements of flow signals were taken over the terminal branches of the ophthalmic artery (supratrochlear and supraorbital arteries) and averaged. Compression of superficial temporal and facial arteries revealed flow direction and common carotid artery compression revealed the supplying blood vessel and the effectiveness of the circle of Willis. Measurements over the common carotid arteries were used to evaluate peripheral resistance. A set of eight criteria was used; the diagnostic value of each criterion was calculated by comparing 138 pathological Doppler findings in 123 patients with the angiograms. If reverse flow direction in supratrochlear or supraorbital artery was used alone, only 43% correct diagnoses would have resulted. A more severe stenosis is not necessarily correlated with a more weighted criterion; a subset of criteria is less efficient than the combination of all criteria. Application during 32 extracranial endarterectomies on 28 patients informed the surgeon immediately about the hemodynamic effect of the surgical intervention. Rethrombosis was diagnosed in two patients by postoperative Doppler examination.

Ultrasonic diagnosis of carotid artery disease.

✓ Ultrasonic echoes from an artery, registered on an oscilloscope screen as vertical deflections from a horizontal baseline, exhibit pulse-synchronous displacements on the x-axis as well as variations in amplitude. The visualization of these echo movements can constitute the basis for an evaluation of arterial conditions comparable to palpation of the pulse but has the advantage of being applicable to arteries that cannot be palpated. The method has been applied to the internal carotid artery in 325 patients, and an evaluation of the method is given on the basis of a comparison with 166 angiograms of the artery. The method has proven to be a valuable diagnostic aid in studying patients suspected of having carotid artery disease.

Studies on Effectiveness of Endarterectomy in Treatment of Carotid Insufficiency

Cerebral ischemia due to carotid artery disease is primarily a mechanical problem of obstruction to flow in the carotid system. Successful surgical treatment, therefore, must be directed toward relief of this obstruction. Critical evaluation of the surgical approach depends on adequate means of measuring the removal of the obstruction. Thirty-seven patients with symptomatic cervical carotid artery disease have been operated upon in the last 4 years in the University of Louisville Hospitals. Several methods have been utilized to measure the effectiveness of the carotid operations. An evaluation of these methods and a discussion of the problems involved in correlating the operative procedure with the clinical course of these patients constitute the purpose of this report. Preoperative Evaluation The presumptive diagnosis of carotid artery disease was confirmed in all patients by preoperative arteriography. In 16 patients bilateral lesions were suspected, and in these cases either bilateral carotid arteriograms or aortic archograms