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1.
To compare contrast-enhanced power Doppler (PD) harmonic imaging (CHI) with contrast-enhanced power Doppler fundamental imaging (CPD) in the depiction of renal cortical vessels, 20 healthy volunteers were subjected to PD imaging and HI assessment of the kidney after bolus injection of Levovist(R) (SH U 508A). System settings were standardized and the pulse-repetition frequencies (PRF) systematically toggled from 750 to 500 and 250. Videotapes were independently reviewed by three readers with regard to the presence of artefacts, the degree of Doppler signal enhancement, demarcation of vessels and the extent of visualization. The assessments were graded separately for each PRF in accordance with a multistage scoring system. In comparison to contrast-enhanced PD, artefacts were significantly lower with CHI for all PRF (p = 0.0001). Vessels were better visualized (p = 0.002) and less blurred (p = 0.006) with CHI than with CPD. There was no significant difference in the extent of Doppler signal increase between CPD and the contrast-enhanced harmonic mode. Combination of the contrast-enhanced harmonic method and PD allows the PRF to be lowered and, by balancing the greater susceptibility of PD to interference from clutter, increases the likelihood of detection of flow in small vessels.  相似文献   

2.
The elderly comprise an increasing proportion of chronic dialysis patients. Recruiting them for continuous peritoneal dialysis (CPD) would help CPD programs maintain a patient population. We retrospectively studied the ability of a prospective evaluation to predict success with CPD in elderly (age greater than 60 years) patients. PD nurses and a renal social worker assigned scores in 10 categories, which were then averaged to obtain an over-all evaluation score. Scores were from 1-5 with 1 = good, 5 = poor, and 3 = average. Thirty-four elderly patients began CPD during the study period. Evaluation scores were available for 28 of these patients before they began dialysis. Evaluation scores less than 3 predicted success with CPD (2.2 +/- 0.2 versus 3.2 +/- 0.4 in patients transferring to hemodialysis, p less than 0.02). Patient motivation and preference were the categories that predicted success with CPD. Elderly patients were more likely than younger patients (those less than 60 years of age) to decline CPD for social reasons (46% versus 4% respectively, p less than 0.001). Elderly patients required more CPD training time than young patients (4.9 +/- 0.7 days versus 3.3 +/- 0.8 days respectively, p less than 0.01). We conclude that a prospective assessment of elderly patients can predict success with CPD and provide information important to individual structuring of CPD training and follow-up.  相似文献   

3.
We examined whether or not the degree of tumor vascularity in lymph node metastases as depicted by color Doppler is associated with a patient's prognosis. Cervical lymph node metastases in 25 patients with head and neck cancer were examined before combined accelerated radiotherapy and chemotherapy. The findings were quantified using a computer-assisted protocol that quantitatively describes color Doppler images by the relative color pixel density (CPD) and the color hues, which are numerically expressed by the mean color value (MCV). We found that, in the patient group with a CPD below median, the median survival was 958 days and, in the group with a higher CPD, it was 423 days (p = 0.05). The time to detection of distant metastases was 18 months with a low CPD, and 6 months with a high CPD (p = 0.05). However, the time to local or nodal progression was not different between the groups. The MCV was not correlated with prognostic data. These results indicate that, in patients with metastatic head and neck cancer, highly vascularized lymph nodes detected with color Doppler sonography may indicate a shorter survival and earlier occurrence of distant metastases.  相似文献   

4.
The aim was to evaluate the predictability of portal diameter (PD) in the diagnosis of esophageal varices (EV) and of large size EV (F3EV) in a large series of patients with cirrhosis. Two-hundred sixty-six persons with cirrhosis (M:F = 153:113; mean age 65.4 +/- 10 y) were studied by abdominal sonography and upper endoscopy. Portal hypertensive gastropathy (PHG) was found in 16.1% and EV was found in 60.9% of patients. Only Child's class (B vs. A: OR 3.4, p < 0.0001; C vs. A: OR 10.3, p < 0.0001; C vs. B: OR 3.1, p = 0.01) and age (OR 1.04, p = 0.03) were independent predictors of EV, whereas PD was not (p = 0.4). Child's class and age were also the only independent predictors of F3EV. Mean PD showed a slight and not significant increase in PHG patients compared with patients with negative endoscopy, a reduction in F1EV patients and then a progressive increase in F2EV and F3EV patients. Patients with PD <12 mm showed a significantly higher prevalence of F1-F2EV (p < 0.05) and a near-significant lower prevalence of endoscopies negative for EV (p = 0.06) than patients with 12 < or = PD < or = 13 mm. PD was not able to predict EV or F3EV in a large series of patients with cirrhosis. The oscillatory trend of PD, proceeding from patients with negative endoscopy to F3EV patients, seems to indicate that EV may unload portal pressure in the initial phases of portal hypertension.  相似文献   

5.
Background, Objectives, and METHODS: The number of patients on chronic peritoneal dialysis (CPD) is increasing rapidly on a global scale. We analyzed the International Pediatric Peritoneal Dialysis Network (IPPN) registry, a global database active in 33 countries spanning a wide range in gross national income (GNI), to identify the impact of economic conditions on CPD practices and outcomes in children and adolescents. ? RESULTS: We observed close associations of GNI with the fraction of very young patients on dialysis, the presence and number of comorbidities, the prevalence of patients with unexplained causes of end-stage kidney disease, and the rate of culture-negative peritonitis. The prevalence of automated PD increased with GNI, but was 46% even in the lowest GNI stratum. The GNI stratum also affected the use of biocompatible peritoneal dialysis fluids, enteral tube feeding, calcium-free phosphate binders, active vitamin D analogs, and erythropoiesis-stimulating agents (ESAs). Patient mortality was strongly affected by GNI (hazard ratio per $10 000: 3.3; 95% confidence interval: 2.0 to 5.5) independently of young patient age and the number of comorbidities present. Patients from low-income countries tended to die more often from infections unrelated to CPD (5 of 9 vs 15 of 61, p = 0.1). The GNI was also a strong independent predictor of standardized height (p < 0.0001), adding to the impact of congenital renal disease, anuria, age at PD start, and dialysis vintage. Patients from the lower economic strata (GNI < $18 000) had higher serum parathyroid hormone (PTH) and lower serum calcium, and achieved lower hemoglobin concentrations. No impact of GNI was observed with regard to CPD technique survival or peritonitis incidence. ? CONCLUSIONS: We conclude that CPD is practiced successfully, albeit with major regional variation related to economic differences, in children around the globe. The variations encompass the acceptance of very young patients and those with associated comorbidities to chronic dialysis programs, the use of automated PD and expensive drugs, and the diagnostic management of peritonitis. These variations in practice related to economic difference do not appear to affect PD technique survival; however, economic conditions seem to affect mortality on dialysis and standardized height, a marker of global child morbidity.  相似文献   

6.
The effect of echo contrast agent on Doppler velocity measurements   总被引:3,自引:0,他引:3  
The purpose of this investigation was to determine the effect of echo contrast agents on spectral Doppler velocity measurements. SH U 508A was administered by IV injection in 15 patients. The transmitral flow velocity was measured at the E- and A-wave peaks before the start and at the peak of the contrast effect. The Doppler velocity was determined from the Doppler video spectral display and from power spectral analysis of the audio Doppler signal. The Doppler signal intensity was also measured. The Doppler signal intensity increased 17.4 +/- 3.5 dB (p < 0.0001) following echo contrast injection. This was associated with a significant increase in the spectral peak velocity as determined from either the video display or audio analysis. (p < 0.0001). The velocity corresponding to the audio power peak frequency (the modal velocity) did not change significantly (p = NS) and was independent of Doppler signal strength.  相似文献   

7.
Sonographic features of phyllodes tumors of the breast.   总被引:11,自引:0,他引:11  
OBJECTIVE: The aim of this study was to examine the sonographic features of phyllodes tumors of the breast. METHODS: Retrospective analysis of prospectively recorded sonographic features was performed on 2268 patients with phyllodes tumors or fibroadenomas during 1995-98. Data from 110 phyllodes tumors (76 benign, 11 borderline, 23 malignant) and 2204 fibroadenomas were analyzed. RESULTS: The patients with phyllodes tumors were older than the patients with fibroadenoma (mean +/- standard error, 39.7 +/- 1.1 years vs. 33.4 +/- 0.3 years; P < 0.0001). Sixty-four percent of patients with phyllodes tumors were aged 31-50 years, while 68.5% of those with fibroadenoma were aged 21-40 years. Phyllodes tumors were larger than fibroadenomas (5.90 +/- 0.43 cm vs. 1.95 +/- 0.03 cm; P < 0.0001). The ratio of length to anteroposterior diameter of phyllodes tumors was smaller than the ratio of length to anteroposterior diameter of fibroadenomas (1.72 +/- 0.06 vs. 1.89 +/- 0.02; P = 0.0105). Seventy-seven percent of phyllodes tumors were lobulated and 79.5% of fibroadenomas were oval. Lobulated shape of the tumor, heterogeneous echo pattern and absence of microcalcification are significant independent sonographic features in multiple logistic regression analysis to distinguish between phyllodes tumors and fibroadenoma. Benign, borderline and malignant phyllodes tumors displayed no significant differences in tumor size or the ratio of length to anteroposterior diameter. CONCLUSIONS: There is a substantial overlap in the sonographic characteristics between phyllodes tumors and fibroadenoma of the breast. If lobulation and heterogeneous hypoechoic internal echoes are observed and calcifications are absent, a diagnosis of phyllodes tumors should be considered. Sonography cannot distinguish between malignant, borderline and benign phyllodes tumors.  相似文献   

8.
PURPOSE: This study was conducted to characterize the spatial distribution of blood vessels in breast fibroadenomas. METHODS: We performed a prospective study to map the anatomic distribution of the vessels in 29 fibroadenomas of the breast using color Doppler sonography. We categorized the detected vessels according to their location in or on the fibroadenoma, counted the different types of vessels, and tested for correlations between vessel distributions or numbers and histopathologic findings. RESULTS: Blood flow was demonstrated in 24/29 (83%) of fibroadenomas. We found 3 vessel types: feeding vessels, which are prominent vessels leading from the surrounding breast tissue into the fibroadenoma; capsular vessels, which are located within the tissue capsule; and segmental vessels, which are located within the fibrous septa of the fibroadenoma. Capsular and segmental vessels were demonstrated in 23/24 (96%) and 24/24 (100%) of the cases, respectively. Feeding vessels were seen in 12/24 (50%) of the cases. Histopathologic analysis revealed the same location and distribution of the vessels as color Doppler imaging. However, there was no correlation between numbers of vessels counted on sonograms and on histopathologic specimens. CONCLUSIONS: Examination of the vascularity demonstrated on color Doppler imaging helps in the diagnosis of benign breast neoplasms such as fibroadenomas.  相似文献   

9.
OBJECTIVE: The purpose of this study was to assess whether endometrial volume (EV) and 3-dimensional (3D) power Doppler indices can discriminate between hyperplasia and endometrial carcinoma and can predict extension of the endometrial carcinoma. METHODS: Eighty-four women with uterine bleeding and a histopathologic diagnosis of endometrial hyperplasia (n = 29) or carcinoma (n = 55) were preoperatively examined by transvaginal 3D sonography and power Doppler angiography. Endometrial thickness (ET), EV, the vascularization index (VI), the flow index (FI), the vascularization-flow index (VFI), and the intratumoral resistive index (RI) were measured. A histopathologic diagnosis was made after endometrial biopsy was performed by hysteroscopy or curettage. RESULTS: The EV and 3D power Doppler indices (VI, FI, and VFI) were significantly higher in endometrial carcinoma than endometrial hyperplasia, whereas the intratumoral RI was significantly lower (P < .05). A VFI of 2.07 was the best cutoff for predicting endometrial carcinoma, with sensitivity of 76.5% and specificity of 80.8%. No significant differences were noticed for ET. The endometrial VI was significantly higher when the tumor stage was greater than I. All the 3D power Doppler indices were significantly higher when the carcinoma infiltrated more than 50% of the myometrium. The intratumoral RI was significantly lower in cases with a high histologic grade, myometrial infiltration of more than 50%, and lymph node metastases. CONCLUSIONS: The VI, 3D power Doppler indices, and the intratumoral RI are more useful than ET for differentiating between hyperplasia and endometrial carcinoma. Intratumoral blood flow evaluated by pulsed Doppler sonography and 3D power Doppler angiography can predict the spread of endometrial carcinoma.  相似文献   

10.
BACKGROUND: Malnutrition-Inflammation Score (MIS) is a quantitative assessment tool based on Subjective Global Assessment (SGA) and predicts mortality and morbidity in maintenance hemodialysis patients. However, there are not enough data about the use of MIS in peritoneal dialysis (PD). In this study, relationships between MIS and prospective hospitalization indices, risk of developing peritonitis, anemia indices, and laboratory and anthropometric parameters were analyzed and compared with SGA in PD. METHODS: 50 PD patients (M/F 26/24, age 45.2 +/- 14.9 years, mean PD duration 30.8 +/- 23.1 months) were included. The same physician performed the SGA and MIS evaluations. Clinical, laboratory, and anthropometric parameters were measured. RESULTS: 18 patients were classified as SGA-A (without malnutrition), 24 as SGA-B (with moderate malnutrition), and 8 as SGA-C (with severe malnutrition). Increment in MIS was concordant with SGA groups A to C (p < 0.0001). Peritonitis rate, number of hospitalizations, total number of hospitalization days, erythropoietin requirements, C-reactive protein (CRP), and ferritin levels were positively correlated with MIS (p < 0.0001). Midarm muscle circumference (p = 0.04), albumin (p < 0.0001), prealbumin (p = 0.001), creatinine (p = 0.04), hemoglobin (p = 0.003), transferrin (p < 0.0001), and cholesterol (p = 0.009) were negatively correlated with MIS. Correlation coefficients of hospitalization indices, peritonitis rate, anemia indices, erythropoietin requirements, albumin, prealbumin, CRP, and anthropometric parameters were higher with MIS than with SGA. In logistic regression analysis, a higher MIS was independently associated with a higher risk of future hospitalization (p = 0.029, odds ratio 2.14, confidence interval 1.082-4.146). CONCLUSIONS: This study demonstrated that MIS significantly correlated with clinical, nutritional, inflammatory, and anthropometric parameters and anemia indices in PD patients, and that those correlations were stronger than those with SGA.  相似文献   

11.
Data on 368 patients with breast carcinomas measuring < or = 5 cm were analyzed to study the relationship between the prognostic factors and the flow indices measured by color Doppler ultrasound (US). Vascularity was detected by color Doppler US in 348 (94.6%) of the 368 breast tumors. Tumors without vascularity were significantly (p = 0.0001) smaller than the tumors with vascularity. There was a correlation between Vmax and tumor size. Postmenopausal women had greater values of RI, PI, and V(max). Tumors larger than 2 cm had significantly greater RI, V(max) and number of vessels as compared with the tumors smaller than 2 cm. RI was significantly greater in the nondiploid tumors than in the diploid tumors. RI > or = 0.7 was significantly associated with nondiploid carcinomas and SPF > or = 7%. Tumor size and Vmax significantly predicted axillary lymph node metastases.  相似文献   

12.
BACKGROUND: Comorbidity is a strong predictor and confounds many studies of outcomes. Previous studies have shown that the Charlson Comorbidity Index (CCI) and the Davies score predict mortality in peritoneal dialysis (PD) patients. However, there are few data on the comparison of comorbidity scores. OBJECTIVE: To compare the CCI (combines comorbidity and age) and Davies score (comorbidity score without age) to see if one score was superior to the other in predicting outcomes. DESIGN: Prospective database study. SETTING: Seven dialysis centers in Western Pennsylvania. PARTICIPANTS: 415 incident PD patients, starting PD from 1/1/90 to 2/1/00. MEASUREMENTS: The CCI and Davies score calculated at the start of PD; serum albumin levels and demographics at the start of PD; total hospitalizations and mortality, collected prospectively. RESULTS: The correlation between CCI and Davies was 0.80, p < 0.0001. The CCI was inversely correlated with serum albumin (-0.31, p < 0.0001). Davies was significantly correlated with age (0.32, p < 0.0001) and inversely correlated with albumin (-0.27, p < 0.0001). The CCI alone was a stronger predictor than Davies alone (score by best subsets regression 49.6 vs 42.0, p = 0.0058). The CCI and Davies with age appeared to be equivalent models of survival (49.61 vs 49.64). The best predictive models were CCI and initial albumin, or Davies, age, and initial albumin. Both CCI and Davies were predictors of hospitalization rates, but the model with the Davies score was better (Akaike information criterion 799.2 vs 850.2). The best predictive model was Davies, albumin, age, and race. CONCLUSIONS: Both comorbidity scores were significant predictors of outcomes, with CCI the stronger predictor for mortality, but the Davies was a stronger predictor of hospitalizations. One or both should be done at the start of dialysis to predict outcome.  相似文献   

13.
The purpose of this study was to evaluate the role of ultrasonography in differentiation between the echogenic characteristics of carcinoma and those of fibroadenoma of the breast. Two mathematical transformations of the measured density on a sonographic image of the breast lesion at three different system gain settings were used in cases of carcinoma (n = 16) and fibroadenoma (n = 31) to provide standardized density values. A significant correlation was found between the tumor and the surrounding tissue densities in both carcinomas (r = 0.77, P = 0.0004) and fibroadenomas (r = 0.79, P < 0.000001. The mean standardized density of the tumor was significantly higher (P < 0.0001) than the surrounding tissue in both carcinomas (2.03 +/- 0.64 D versus 1.23 +/- 0.38 D) and fibroadenomas (2.09 +/- 0.48 D versus 1.33 +/- 0.3 D). However, the differences between density values of carcinoma and fibroadenomas were not significantly different. The data suggest that it may not be possible to differentiate breast carcinoma and fibroadenomas on the basis of the echogenicity of solid breast masses.  相似文献   

14.
The majority of menopausal women suffer from climacteric symptoms. The purpose of this study was to assess the effects of acupuncture on the quality of life and reproductive hormones secretion in menopausal women. Eleven (11) menopausal women with climacteric symptoms entered this prospective study. The Menopause Specific Quality of life Questionnaire was filled out by the patients before the first acupuncture session, after the last one (5 weeks later), and 3 months after the last acupuncture session. Reproductive hormones including follicular-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, progesterone, and prolactin were measured before and after treatment. Acupuncture significantly improved menopausal vasomotor symptoms (p = 0.001 and p = 0.003 for the end of treatment and 3 months later, respectively) and physical symptoms (p = 0.014 at the end of treatment and p = 0.046 3 months later). It did not change psychosocial or sexual symptoms, nor did it change the measured reproductive hormones. In conclusion, acupuncture is shown to be effective in relieving vasomotor and physical disturbances of menopausal women with effects lasting at least up to 3 months after termination of the treatment. Acupuncture may be a useful treatment alternative for women who are unable or do not want to receive hormone replacement therapy. A prospective study with larger sample sizes will be needed to define the role of acupuncture in the management of menopausal symptoms.  相似文献   

15.
OBJECTIVES: Body composition changes occur in peritoneal dialysis (PD) due to abnormalities in nutrition and hydration. We investigated abnormalities of nutrition and hydration in PD patients compared with healthy controls by measurement of total body potassium (TBK) and body water compartments. DESIGN: Cross-sectional comparison study. METHODS: We measured TBK--an indicator of body cell mass--by whole body counting, total body water (TBW) by deuterium oxide dilution, and extracellular water (ECW) by bromide dilution in 29 PD patients and 32 controls. RESULTS: The absolute mean value of TBK for PD patients was not significantly lower than in controls. The ratios of observed TBK to predicted TBK from prediction formulas were compared. Equations used were those of Boddy, Bruce, Burkinshaw, and Ellis and our own equation derived from a local control database (Leeds). Observed/predicted ratios of TBK were significantly less in PD than in control subjects for all equations. Water volumes did not differ between PD and control groups. Observed/predicted ratios for TBK in PD patients correlated with serum potassium (Boddy r = 0.355, p = 0.06; Bruce r = 0.411, p < 0.05; Burkinshaw r = 0.457, p < 0.01; Leeds r = 0.412, p < or = 0.05; Ellis r = 0.356, p = 0.06) and tended to correlate with serum albumin (Bruce r = 0.343, p = 0.07; Burkinshaw r = 0.421, p < 0.05; Leeds r = 0.357, p = 0.06; Ellis r = 0.310, p = NS). There was no relationship with serum potassium in controls. Serum albumin in PD correlated with TBK (r = 0.445, p < 0.02), TBK/height (r = 0.419, p < 0.05), TBK/weight (r = 0.554, p = 0.002), and TBK/TBW (r = 0.586, p = 0.0001). Extracellular water/intracellular water (ECW/ICW) was inversely related to TBK (r = -0.455, p < 0.02 in PD; r = -0.387, p < 0.05 in controls) and to TBK/height (r = -0.446, p < 0.02 in PD; r = -0.411, p = 0.02 in controls). TBK/weight reduced with age in PD (r = -0.445, p < 0.02), as did TBK/TBW in PD (r = -0.463, p < 0.02). ECW/ICW tended to increase with age in PD (r = 0.351, p = 0.06). CONCLUSIONS: Observed/predicted ratio of TBK is reduced in PD patients relative to healthy controls, indicating reduced body cell mass. Serum albumin and potassium reflect TBK indices in PD. Body water volumes did not differ between PD and controls, implying no overall abnormality in hydration in the PD group. However, ECW is relatively increased compared to ICW with decreasing TBK indices, suggesting relative ECW expansion with reduction in body cell mass.  相似文献   

16.
PURPOSE: The aim of this study was to determine the histopathologic grades of hepatocellular carcinomas (HCCs) on the basis of the presence of Kupffer cells, using color Doppler sonography with the liver-specific microbubble contrast agent Levovist. METHODS: Color Doppler sonograms generated by stimulated acoustic emission were obtained 7 minutes after intravenous injection of 5 ml of Levovist (300 mg/dl) in patients with histopathologically confirmed HCCs. CT scans were also obtained and evaluated, and hematoxylin and eosin staining for morphologic examination and immunostaining (anti-CD68) for detecting Kupffer cells were performed for confirmation of the sonographic findings. RESULTS: Eighteen tumors had a defect in the color Doppler signal (color void) that corresponded with the baseline gray-scale image of the tumor. On histopathologic examination, these 18 tumors were all found to be either poorly or moderately differentiated HCCs with either a marked reduction in the number of or the absence of Kupffer cells. The remaining 2 tumors showed color signals. Histopathologic examination of these 2 tumors disclosed well-differentiated components within the tumors, with Kupffer cells in the tumor tissue. CONCLUSIONS: Color Doppler sonography using a liver-specific microbubble ultrasound contrast agent appears to reflect the histopathologic features of HCCs and may thus be useful for differentiating liver tumors and determining a treatment strategy.  相似文献   

17.
Lesions of focal nodular hyperplasia are hypervascular, benign focal liver lesions whose differentiation from other focal liver lesions is of significant clinical relevance. The purpose of this study was to investigate the echo-enhancing agent SHU 508A (Levovist) in the evaluation of focal nodular hyperplasia with Doppler sonography. We examined 49 patients with 71 lesions of focal nodular hyperplasia in the liver with gray scale and power Doppler sonography. In all patients Levovist was administered intravenously in a concentration of 300 to 400 mg galactose per milliliter. Visualization of the feeding vessels and the vascularity of the lesions were evaluated, and the resistive indices in the feeders and the hepatic arteries were assessed. In comparison with unenhanced power Doppler sonography, echo-enhanced power Doppler sonography yields a higher sensitivity in the detection of the feeding artery (97% versus 82%) in focal nodular hyperplasia and in the depiction of the radial vascular architecture in such lesions, especially those located in the left lobe of the liver. Lesions less than 3 cm in diameter do not consistently show a characteristic vascular architecture with echo-enhanced Doppler sonography. The resistive index of the tumor-feeding artery (mean, 0.51 +/- 0.09) is significantly (P < 0.0001) lower than that of the hepatic artery (mean, 0.65 +/- 0.06) and decreases as the size of the focal nodular hyperplasia increases. The administration of Levovist may improve the signal-to-noise ratio and thus visualization of the vascular architecture in focal nodular hyperplasia. Lesions located in the left lobe of the liver, which commonly are subject to disturbing motion artifacts in color Doppler sonography, will significantly benefit from the administration of Levovist. Echo-enhanced power Doppler sonography, however, is not capable of depicting a characteristic vascular pattern in small (< or = 3 cm) lesions of focal nodular hyperplasia that would guarantee a specific diagnosis.  相似文献   

18.
Normal values for left anterior descending coronary artery (LAD) flow velocity were assessed from a large number of normal children. In 303 healthy children, LAD peak flow velocity was measured by Doppler echocardiography. LAD peak flow velocities were calculated considering the angle between the Doppler beam and the coronary flow direction. The flow signals of LAD were recorded in 95% (288/303). The mean angle between the Doppler beam and Doppler flow signals of LAD was 42 +/- 8 degrees. The ratio of AT to total diastolic spectral duration was 0.19 +/- 0.088 and constant with age. LAD peak flow velocity correlated significantly with age (r = -0.57, p < 0.0001) and heart rate (r = 0.63, p < 0.0001). Multiple linear regression analysis showed that LAD peak flow velocity was associated with age and heart rate (LAD peak flow velocity = 20-0.34 (age) + 0.16 (heart rate), r2 = 0.41, p < 0 .0001). Normal data obtained in the present study provide a basis of the understanding and investigation in children with congenital heart disease or acquired heart disease such as atherosclerosis, left ventricular hypertrophy, or Kawasaki's disease.  相似文献   

19.
This study was designed to evaluate power Doppler imaging for assessment of urinary bladder neck blood flow in comparison with laser Doppler flowmetry (LDF) in an animal model. Transrectal power Doppler ultrasound (US) and LDF of the urinary bladder neck were performed in three anesthetized pigs during comparative cystometry. Normal saline (NaCl) was used for the first run, followed by a second run with 0.2 mol/L potassium chloride (KCl). Standardized sonographic equipment settings (Acuson Sequoia 512); MountainView, CA) were used for power Doppler imaging. Computer-assisted calculation of color pixel density (CPD) of power Doppler images was performed using Scion Image) software image analysis. Tissue perfusion units (TPU) were measured using a BLF21 laser Doppler flowmeter (Transonic Systems Inc., Ithaca, NY, USA). The power Doppler results were compared with the findings obtained by LDF. NaCl filling resulted in a mean CPD increase at the bladder neck from 18.65 (+/- 1.78) at empty bladder to 37.8 (+/- 1.84) at 100 mL and to 88.32 (+/- 1.35) at full bladder capacity (C(max)) of 270 mL, respectively. With KCl filling, a mean CPD increase from 18.65 (+/- 1.78) to 59.63 (+/- 0.5) at 100 mL and 110.82 (+/- 2.98) at full bladder capacity (270 mL) was observed. The CPD increase was significantly higher for KCl than with NaCl (p < 0.001). With NaCl filling, bladder neck blood flow increased from 22 TPU (empty) to 46 TPU (100 mL) and 62.5 TPU at C(max), compared to 22 TPU, 50 TPU and 102.5 TPU with KCl. CPD and TPU measurements showed a strong correlation at p = 0.01. In conclusion, transrectal power Doppler US image quantification is a feasible and accurate method for assessing blood flow changes in the urinary bladder neck.  相似文献   

20.
We aimed to evaluate objectively the value of color Doppler flow imaging in the assessment of response of locally advanced breast cancer to primary medical treatment by using a computer assisted semiquantitative method. Prior to and after neoadjuvant treatment, 17 patients with locally advanced breast carcinoma were prospectively evaluated by physical examination and computer assisted semiquantitative color Doppler ultrasonography. The results of clinical and color Doppler examination were finally correlated to the histopathologic evaluation of tumor response. The degree of concordance between posttherapeutic histopathologic results, clinical examination, and color Doppler assessment was evaluated by kappa statistics. Concordance was 0.474 (0.135-0.813) between histopathologic results and clinical posttherapeutic assessment and 0.870 (0.627-1.113) between histopathologic results and semiquantitative color Doppler examination. Objective semiquantitative assessment of tumor vascularity as displayed by color Doppler ultrasonography has potential as a functional tool for measuring tumor response to neoadjuvant chemotherapy.  相似文献   

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