Ultrasound Tissue Characterization Research Articles

Ultrasound tissue characterization with the gray level histogram width of the B-mode

Ultrasound tissue characterization with the gray level histogram width of the B-mode

Ultrasound Tissue Characterization by Integrated Backscatter for Analyzing Fluorouracil Induced Myocardial Damage

5-Fluorouracil (5-FU) cardiotoxicity is a well-known clinical phenomenon whose pathophysiology remains controversial. Cyclic variation of integrated backscatter (CVIBS) assesses acoustic properties of myocardium that may reflect both contractility and structural changes. The aim of this study was to evaluate CVIBS alterations in cancer patients under high-dose leucovorin and infusional 5-FU (HDLV5FU) chemotherapy. We prospectively evaluated 37 cancer patients under HDLV5FU treatment. Transthoracic echocardiography and CVIBS were performed at the 0th, 48th hours, and on day 15 of the first cycle. The parasternal long-axis view was preferred to obtain the image of integrated backscatter and mainly two regions of interest--interventricular septum (IVS) and posterior wall (PW)--were used. Clinical cardiotoxicity was observed in two patients. No significant differences were detected in pre- and posttreatment conventional echocardiography evaluations. However, both the IVS (9.3 +/- 1.0 to 8.1 +/- 1.2 dB, P < 0.001) and PW (9.1 +/- 0.7 to 7.8 +/- 0.9 dB, P < 0.001) CVIBS values significantly decreased in all patients. All values were returned to pretreatment levels (9.2 +/- 0.9 dB in the CVIBS-IVS and 8.9 +/- 0.6 dB in CVIBS-PW, respectively) on day 15 after the treatments. This study suggests that HDLV5FU may cause acute transient alterations in CVIBS values in the absence of clinical symptoms and signs of cardiotoxicity. The clinical value of CVIBS should be further studied in patients receiving 5-FU-based therapy.

Assessment of arterial medial characteristics in human carotid arteries using integrated backscatter ultrasound and its histological implications

Recently, ultrasound tissue characterization of the carotid arteries with an integrated backscatter (IB) analysis was shown to identify a high-risk group of atherosclerosis. To clarify whether IB ultrasound is useful in assessing arterial sclerosis as well as stiffness β and whether IB values reflect the histological structure, we measured IB values of common carotid media in 52 subjects without coronary risk factors and in 10 patients with systemic sclerosis (SSc) in the clinical studies and 12 patients in the histological studies with a Philips Medical Systems Sonos 5500. IB values were correlated with age ( r = 0.69, P < 0.0001), intima-media thickness ( r = 0.72, P < 0.0001) and stiffness β ( r = 0.80, P < 0.0001) in the control subjects. IB values and stiffness β in the SSc group were greater than in an age- and sex-matched control group (IB values: 9.6 ± 2.7 dB versus 16.1 ± 1.8 dB; stiffness β: 11.5 ± 4.5 versus 20.6 ± 5.6, P < 0.01). IB values of the media were correlated with the elastic fragmentation index ( r = 0.63, P = 0.029) and the collagen fiber index ( r = 0.59, P = 0.046). Measurements of IB values of carotid media are useful for non-invasively evaluating arterial sclerosis.

Early myocardial abnormalities in asymptomatic patients with severe isolated congenital aortic regurgitation: An ultrasound tissue characterization and strain rate study

Aortic valve regurgitation (AR) in the pediatric population has increased in recent years because of the expanded use of new surgical and hemodynamic procedures. Unlike adult patients, few predictors for the need of operation have been proposed in young asymptomatic or mildly symptomatic patients with AR. To unmask early abnormalities of left ventricular (LV) function, 59 participants were enrolled: 14 asymptomatic patients (mean age 18 years) with congenital isolated severe AR and normal LV function (LV ejection fraction > 50%); and 45 healthy control subjects with comparable age and body surface area. All the studied population underwent standard echocardiographic examination, integrated backscatter, and strain rate imaging study. Conventional echocardiographic indices of global LV systolic performance for patients with AR were similar to that of control subjects. Compared with control subjects, integrated backscatter analysis demonstrated a significant reduction in cyclic variation in both septal and posterior walls ( P < .05). LV radial and longitudinal deformation properties for patients with AR were significantly reduced ( P < .05) as assessed by peak systolic strain rate. Our results demonstrated the ability of integrated backscatter and strain rate imaging to detect early subclinical abnormalities in young patients with severe congenital AR despite the presence of a normal ejection fraction.

Quantitative study on liver and kidney of liver fibrosis with ultrasound tissue characterization

目的 探讨超声组织定征(UTC)对慢性乙型肝炎肝纤维化患者肝脏回声改变与自身肾脏实质回声相对不变的对比变化,以期发现新的诊断肝脏纤维化的检查方法.方法用UTC视频法测量慢性乙型肝炎患者肝脏和肾实质二维声图像的灰阶值,并将两组灰阶值进行统计学分析.结果慢性乙型肝炎肝纤维化患者的肝脏与肾脏实质二维声像图的灰阶值差异有显著意义(P＜0.001).结论比较用TUC视频法测得的慢性乙型肝炎肝纤维化患者肝脏和肾脏实质的声像图灰阶值可作为慢性乙型肝炎临床诊断的检查方法之一。

Ultrasound tissue characterization with the gray level histogram width of the B-mode

AbstractObjectives. We investigated fetal lung immaturity, fetal brain periventricular echodensity (PVE) and other problems related to changes in fetal tissue by non-invasive ultrasound tissue characterization, using a commonly available real-time B-mode ultrasound machine.Methods. Histograms of a region of interest (ROI) were displayed on a B-mode screen. The base length of a histogram divided by the full gray-scale length gave the gray level histogram width (GLHW); this value is insensitive to changes in B-mode model, device gain or image depth. Any variation in the magnitude of GLHW in high-contrast images was easily corrected. Fetal lung immaturity was suspected when the fetal lung GLHW was less than that of normal fetal lung and fetal liver after 30 weeks of pregnancy. The GLHW values of fetal brain PVE were also compared to those of normal fetal brain.Results. GLHW values were compared between the “mature fetal lung” and the “immature fetal lung” groups, as determined by the stable microbubble test:...

The value of quantitative ultrasound tissue characterization of the cervix and rapid fetal fibronectin in predicting preterm delivery

To evaluate clinical risk factors, cervical fetal fibronectin (fFN), cervical length, and mean gray value assessment in predicting of preterm delivery (PTD) in patients with signs and/or symptoms of preterm labor (PTL). One hundred and seventeen women with PTL between 24 and 34 weeks of gestation were included. Cervical swabs were tested for fFN using the rapid fFN assay. When 2-dimensional transvaginal ultrasound measurement of cervical length was completed, a region of interest (ROI) of constant size was defined in the midsection of the posterior wall, and the tissue-specific gray scale was determined. The end point were PTDs at <34 and <37 weeks of gestation. In univariate analysis, the three strongest predictors of spontaneous preterm birth <34 weeks were positive fFN (relative risk [RR] 8.9; 95% confidence interval [CI] 2.6-30.1), cervical length < or =2.5 cm (RR 6.9; 95% CI 1.6-29.7), and a low mean gray value of < or =5.97 (RR 7.9; 95% CI 2.3-27.2). Predictors significantly associated with spontaneous PTD at less than 37 weeks of gestation included previous PTD in multiparas (RR 3.9; 95% CI 1.6-9.5), positive fFN (RR 7.6; 95% CI 3.8-15.3), cervical length < or =2.5 cm (RR 2.6; 95% CI 1.4-5.1) and a low gray scale value of < or =6.54 (RR 4.5; 95% CI 2.3-8.9). In the final regression models used to predict spontaneous PTD <34 weeks and <37 weeks of gestation, both a positive fetal fibronectin (odds ratio [OR] 13.4; 95% CI, 2.5-72.1, P=0.003 vs. OR, 17.3; 95% CI 4.9-61.8, P<0.001) and a low gray scale value (OR 6.3 95% CI 1.3-29.4, P=0.02 vs. OR, 7.1; 95% CI 2-25.2, P=0.003) remained powerful predictors. The RRs of spontaneous PTD <37 weeks has been analyzed by a combination of these significant parameters. Low mean gray value < or =6.54 and negative fFN had a 10.3-fold (95% CI 2-74.5) increased risk of spontaneous preterm birth at <37 weeks. Combination of positive fFN and normal gray level (>6.54), had a higher increase risk of PTD (RR 18.1; 95% CI 4.4-76.7). When both factors were positive, the RR increases to 24.8 (95% CI 6.2-98.7). Combined use of rapid fFN and cervical gray value analysis improves the diagnostic efficiency and allows identification of women at risk for preterm delivery and in need for further prophylactic/therapeutic intervention.

Estimation of ultrasound attenuation and dispersion using short time Fourier transform

Determination of the acoustic attenuation and dispersion has important applications in ultrasound tissue characterization and non-destructive material testing. Current signal processing methods Fourier transform of ultrasound signals to get the spectra of amplitude and phase to estimate respectively the attenuation and dispersion of a given medium. These methods are frequency domain method and obsessed with ambiguity issue in the phase unwrapping calculation. Conventional ultrasound velocity measuring method detects the time of arrival of a pulse (or echo) signal, which is a time domain method to compute group velocity (not phase velocity). This paper presents a novel approach based on the short time Fourier transform (STFT)—a time-frequency analysis, to estimate the ultrasonic dispersion and attenuation. Only the amplitude information of the pulse-signal spectra is used. Based on the time-frequency presentation, the attenuation coefficient of the signal is obtained by computing the amplitude decay of pulse spectrum in time domain, while phase velocities are obtained based on the “time–of–flight” (TOF) of the mono frequency component of the pulse signals. As a result, we eliminate the ambiguity issue in phase angle calculation. Furthermore, the proposed method makes the phase velocity pedagogically intuitive for novice users. The paper presents experiments to evaluate demonstrate the performance of the proposed method.

The influence of growth hormone therapy on ultrasound myocardial tissue characterization in patients with childhood onset GH deficiency

Background: In growth hormone deficiency (GHD), a reduction in left ventricular mass (LV-mass) and impairment of systolic function has been shown. In this study, we investigated the effects of 12 months of GH replacement therapy on cardiac structure and functional indices measured by echocardiographic techniques in adult patients with childhood onset GH deficiency. Methods: Sixteen patients (age 42.3±13.1 years, 10 males) were investigated before and after 12 months of GH treatment at a dose of 0.02 IU/kg/day (7 μg/kg/day). Echocardiography was performed including the ultrasound myocardial tissue characterization technique. We measured two parameters of the ultrasonic tissue characterization with integrated backscatter: the magnitude of the cardiac-cycle-dependent variation in integrated backscatter signals (CV-IBS) and the mean value of integrated backscatter signals calibrated by the pericardium (cal-IBS). Results: Left ventricular diameter and wall thickness did not change after GH treatment, although systolic increase in interventricular septum thickness (IVS%) and systolic increase in posterior wall thickness (PWT%) increased significantly (IVS% 52.2±31.9% vs. 67.3±30.4% and PWT% 48.7±20.2% vs. 58.0±17.7%, p<0.01 and p<0.01, respectively). Ejection fraction increased from 56.2±7.2% to 63.2±6.1% ( p<0.01). LV-mass index did not change after GH treatment (78.4±22.1 vs. 81.9±21.1 g/m 2). CV-IBS increased significantly after GH treatment ( p<0.05), in both the interventricular septum and the left ventricular posterior wall (4.7±1.5 vs. 5.8±1.9 dB for the interventricular septum, 4.9±1.8 vs. 6.5±2.4 dB for the left ventricular posterior wall, p<0.05 and p<0.05, respectively). Cal-IBS also increased significantly after GH treatment (−23.5±4.1 vs.−21.8±4.2 dB for the interventricular septum, −23.0±4.4 vs. −21.8±4.3 dB for the left ventricular posterior wall, p<0.01 and p<0.05, respectively). Conclusion: Twelve months GH treatment in adults with childhood onset GHD resulted in improvement of cardiac contractile performance. Observed changes in cal-IBS and CV-IBS suggest that GH treatment in this patient group can lead to a further somatic maturation of the heart, probably not accomplished previously.

Carotid plaque spaces relate to symptoms and ultrasound scattering

We have previously found that spectral analysis of ultrasound (US) can discriminate in vitro plaques from asymptomatic and symptomatic (transient ischemic attack within previous 4 weeks) patients. That study found no differences in percentages of lipid or thrombus between the two groups by optical microscopy/planimetry. The present study was to find out if another feature from the microscopy could show a difference. The number and size of spaces resulting from cell death or new blood vessels were measured to see if they related to symptoms or could help explain US differentiation. Twelve plaques from each group were examined by optical microscopy. The sizes and concentrations of two kinds of spaces, endothelial lined (vessel spaces) and unlined (tissue spaces), were correlated both with symptoms and also with the US tissue characterization scores from the previous study. Symptomatic vs. asymptomatic plaques showed a higher concentration and a larger size: 0.87 vs. 0.21 per mm 2 ( p < 0.005) and 154 vs. 110 μm ( p < 0.02). A discriminant function of spaces with symptoms as dependent variables correctly identified 91.7% of the plaques ( p < 0.001). The concentration in plaques previously designated by US as true positive plaques or true negative was 1.21 vs. 0.22 per mm 2 ( p < 0.005). spaces were increased in plaques of symptomatic patients and were related to UTC scores. Both the lined and unlined spaces were useful as predictors. ( Jeffrey.Justin@Drexel.edu)

Ultrasonic delineation of aortic microstructure: the relative contribution of elastin and collagen to aortic elasticity.

Aortic elasticity is an important factor in hemodynamic health, and compromised aortic compliance affects not only arterial dynamics but also myocardial function. A variety of pathologic processes (e.g., diabetes, Marfan's syndrome, hypertension) can affect aortic elasticity by altering the microstructure and composition of the elastin and collagen fiber networks within the tunica media. Ultrasound tissue characterization techniques can be used to obtain direct measurements of the stiffness coefficients of aorta by measurement of the speed of sound in specific directions. In this study we sought to define the contributions of elastin and collagen to the mechanical properties of aortic media by measuring the magnitude and directional dependence of the speed of sound before and after selective isolation of either the collagen or elastin fiber matrix. Formalin-fixed porcine aortas were sectioned for insonification in the circumferential, longitudinal, or radial direction and examined using high-frequency (50 MHz) ultrasound microscopy. Isolation of the collagen or elastin fiber matrices was accomplished through treatment with NaOH or formic acid, respectively. The results suggest that elastin is the primary contributor to aortic medial stiffness in the unloaded state, and that there is relatively little anisotropy in the speed of sound or stiffness in the aortic wall.

1037-145 Ultrasound myocardial tissue characterization allows early detection of cardiac involvement in patients with sarcoidosis

1037-145 Ultrasound myocardial tissue characterization allows early detection of cardiac involvement in patients with sarcoidosis

Ultrasound Tissue Characterization Detects Preclinical Myocardial Structural Changes in Children Affected by Duchenne Muscular Dystrophy

Ultrasound Tissue Characterization Detects Preclinical Myocardial Structural Changes in Children Affected by Duchenne Muscular Dystrophy

Myocardial ultrasound tissue characterization in patients with hypertrophic cardiomyopathy: noninvasive evidence of electrical and textural substrate for ventricular arrhythmias

Background Although in patients with hypertrophic cardiomyopathy (HCM) pathologic studies seem to suggest a correlation between morphologic findings and arrhythmias, it has never been confirmed in the clinical setting. Objective We sought to noninvasively assess the electrical and textural properties of the myocardium and to define their potential relationship in patients with HCM. Methods We studied 48 patients: 22 with HCM (mean age: 22 ± 5.1 years) and 26 age- and body surface area–matched healthy patients. They underwent a standard echocardiographic examination to assess left ventricular size and thickness. In addition, by integrated backscatter analysis, we assessed textural properties of left ventricular myocardium with calibrated averaged intensity (IB) and to assess functional properties of the myocardium with cyclic variation, both at the interventricular septum (IVS) and posterior wall. Finally, we studied ventricular late potentials (VLPs) by signal-averaged electrocardiography and performed a 24-hour electrocardiography Holter monitoring to respectively define electrical instability and ventricular arrhythmias. Results Compared with control patients, patients with HCM had, both at IVS and posterior wall, increased IB (−28.8 ± 10 vs −35 ± 4 dB [ P = .007] and −29 ± 8 vs −33 ± 5 dB [ P < .035], respectively) and decreased cyclic variation (6.8 ± 2.7 vs 10.3 ± 2.3 dB [ P < .001] and 8.2 ± 2.9 vs 11.4 ± 2.1 dB [ P < .001], respectively). In all, 5 patients with HCM had positivity of VLPs, and 4 of them showed nonsustained ventricular tachycardia (nsVT) on the Holter monitoring. Compared with patients who had HCM without VLPs and nsVT, patients with positivity of VLPs and nsVT showed higher IB both at IVS (−15.8 ± 8.4 vs −32.6 ± 5.9 dB [ P < .001] and −16.6 ± 9.5 vs −31.5 ± 7.5 dB [ P = .002], respectively) and at posterior wall (−19.08 ± 8.42 vs −32.5 ± 4.2 dB [ P < .001] and −22.4 ± 4.6 vs −31 ± 7.5 [ P = .04], respectively). A multivariate analysis showed IB at IVS ( P = .042; odds ratio = 1.19) and positivity of VLPs ( P = .026; odds ratio = 3.67) as independent predictors of nsVT. Conclusion Patients with HCM showed abnormal morphologic and electrical properties of the myocardium. The correlation between VLPs and IB at IVS and their relationship with nsVT suggests a link between textural and electrical nonhomogeneity of myocardial fibers, a potential substrate of nsVT in patients with HCM.

Evaluation of quantitative ultrasound tissue characterization of the cervix and cervical length in the prediction of premature delivery for patients with spontaneous preterm labor

OBJECTIVE: This study was to evaluate the predictive value of the uterine cervix tissue with the use of quantitative ultrasound gray level analysis for preterm delivery. STUDY DESIGN: Sixty-eight patients with preterm labor between 20 and 35 weeks of gestation were included. When two-dimensional transvaginal ultrasound measurement of cervical length was completed, a region of interest of constant size was defined in the midsection of the posterior wall, and the tissue-specific gray scale was determined. Preterm delivery of <37 weeks of gestation was sought. RESULTS: Twenty-eight patients (41.2%) were delivered preterm. The risk for preterm delivery was increased significantly in patients with cervical length of ≤2.5 cm (odds ratio, 7.67; 95% CI, 2.4-24.45), with Bishop score of ≥4 (odds ratio, 3.44; 95% CI, 1.21-9.75), and with decreased mean gray scale value (odds ratio, 12.13; 95% CI, 3.69-39.88). Parity and uterine contractions were not significant as predictors for preterm delivery, although the risk for preterm delivery increased with higher parity (odds ratio, 1.8; 95% CI, 0.68-4.79). The risk for preterm delivery remained nearly the same by uterine contractions (odds ratio, 0.92; 95% CI, 0.28-3.01). A mean scale value of ≤6.54 had the best cutoff value for the prediction of preterm delivery. For preterm delivery, a mean gray value ≤6.54 had a sensitivity of 82.1%, a specificity of 72.5%, a positive predictive value of 67.6%, and a negative predictive value 85.3%. Multiple logistic regression analysis indicated that, even when other variables are considered simultaneously, the mean gray scale value is the single best predictor of preterm delivery. CONCLUSION: Quantitative ultrasound tissue characterization of the uterine cervix predicts premature delivery and provides additional information in the prediction of potential premature delivery.

Ultrasound tissue characterization detectspreclinical myocardial structural changes inchildren affected by Duchenne muscular dystrophy

ObjectivesOur goal was to identify early changes in myocardial physical properties in children with Duchenne muscular dystrophy (DMDch). BackgroundDuchenne muscular dystrophy (DMD) is caused by the absence of dystrophin, which triggers complex molecular and biological events in skeletal and cardiac muscle tissues. Although about 30% of patients display overt signs of cardiomyopathy in the late stage of the disease, it is unknown whether changes in myocardial physical properties can be detected in the early (preclinical) stages of the disease. MethodsWe performed an ultrasonic tissue characterization (UTC) analysis of myocardium in DMDch with normal systolic myocardial function and no signs of cardiomyopathy. Both the cyclic variation of integrated backscatter (cvIBS) and the calibrated integrated backscatter (cIBS) were assessed in 8 myocardial regions of 20 DMDch, age 7 ± 2 years (range 4 to 10 years), and in 20 age-matched healthy controls. ResultsWe found large differences in the UTC data between DMDch and controls; the mean value of cvIBS was 4.4 ± 1.5 dB versus 8.8 ± 0.8 dB, whereas the mean value of cIBS was 36.4 ± 7.1 dB versus 26.9 ± 2.0 dB (p < 10−6for both). In DMDch, all eight sampled segments showed cIBS mean values to be significantly higher and cvIBS mean values to be significantly lower than those in the controls. Finally, interindividual differences were greater in DMDch than in controls for both parameters. ConclusionsThe myocardium in DMDch displays UTC features different from those in healthy controls. These results show that lack of dystrophin is commonly associated with changes in myocardial features well before the onset of changes of systolic function and overt cardiomyopathy.

Ultrasound tissue characterization in patients with primary and secondary hypertension: influence of the renin-angiotensin-aldosterone system

Ultrasound tissue characterization in patients with primary and secondary hypertension: influence of the renin-angiotensin-aldosterone system

P1113 The influence of growth hormone therapy on ultrasound myocardial tissue characterization in patients with childhood onset growth hormone deficiency

P1113 The influence of growth hormone therapy on ultrasound myocardial tissue characterization in patients with childhood onset growth hormone deficiency

Why does dobutamine stress echocardiography have lower sensitivity in patients with concentric remodeling? A study of myocardial abnormalities with ultrasound tissue characterization and strain rate imaging

Why does dobutamine stress echocardiography have lower sensitivity in patients with concentric remodeling? A study of myocardial abnormalities with ultrasound tissue characterization and strain rate imaging

Early detection of doxorubicin-induced myocardial damage by ultrasound tissue characterization with integrated backscatter.

Doxorubicin (DXR) is one of the most effective antineoplastic agents, but its use is limited by its myocardial toxicity. Myocardial injury reduces the cyclic variation of integrated backscatter (CV-IBS) and so the present study was designed to investigate whether CV-IBS can be used to detect the early phase of myocardial damage in patients receiving DXR. Thirty-four subjects constituted the study population, none of whom showed clinically evident heart failure. CV-IBS was obtained for both the interventricular septum and the left ventricular posterior wall in the parasternal short-axis view. Standard echographic measures of left ventricular function were also made. Subjects without DXR exposure or evident cardiac diseases served as controls. The total dose of DXR administered per patient was 339+/-164 mg/m2 (range: 95-680 mg/m2). Conventional echographic parameters, including left ventricular wall thickness, dimensions, fractional shortening, and ejection fraction, showed no significant differences between the 2 groups. In contrast, CV-IBS was significantly decreased in the DXR group compared with the control group (septum: 4.7+/-1.7 vs 7.2+/-1.9 dB, p<0.0001; posterior wall: 6.7 +/-2.2 vs 8.0+/-1.6 dB, p<0.05). CV-IBS can be used as an early indicator of DXR-induced myocardial damage in patients demonstrating normal left ventricular systolic function.