Doppler US Findings Research Articles

Gray scale and power Doppler US in the preoperative evaluation of axillary metastases in breast cancer patients with no palpable lymph nodes

The purpose of this study is to evaluate the accuracy of gray scale and Doppler US findings in the detection of axillary metastases in breast cancer patients with no palpable lymph nodes. One-hundred and ninety-eight lymph nodes detected in 83 women were evaluated. The size and longitudinal/transverse axis ratios of each node were documented. Absence of echogenic hilum, asymmetrical cortical thickening, and presence of peripheral flow were prospectively considered signs of malignancy. Histopathologically, there were 93 malignant and 105 benign nodes. The above criteria and a low longitudinal-transverse axis ratio were statistically significant for malignancy. In lymph nodes smaller than 1 cm, only asymmetric cortical thickening and presence of peripheral flow were significant. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of US were 86.49, 93.62, 91.43, 89.8 and 90.48%, respectively. In conclusion, US is successful and reliable in the determination of axillary metastatic involvement in nonpalpable and small lymph nodes. Inclusion of axillary US in the preoperative diagnostic evaluation would be complimentary to sentinel node biopsy, and also could eliminate the need for it in patients with positive US results, after confirmation with biopsy.

Color Doppler US findings in the diagnosis of arterial occlusive disease of the lower limb.

Peripheral arterial occlusive disease (PAOD) of the lower limb is a widely spread disease at the present time. After clinical examination, which includes a comprehensive history of the patient, different imaging modalities are competitive in the exact assessment of PAOD. Besides digital subtraction angiography and MR -angiography, color Doppler US is an established imaging modality in the diagnosis of PAOD. This article illustrates the typical color Doppler US findings in PAOD of the lower limb. Duplex images of normal and pathological findings are presented, and the limitations of the method are pointed out. Color Doppler US examination strategies in patients suffering of PAOD are outlined.

Color Doppler us Findings in the Diagnosis of Arterial Occlusive Disease of the Lower Limb

Peripheral arterial occlusive disease (PAOD) of the lower limb is a widely spread disease at the present time. After clinical examination, which includes a comprehensive history of the patient, different imaging modalities are competitive in the exact assessment of PAOD. Besides digital subtraction angiography and MR -angiography, color Doppler US is an established imaging modality in the diagnosis of PAOD. This article illustrates the typical color Doppler US findings in PAOD of the lower limb. Duplex images of normal and pathological findings are presented, and the limitations of the method are pointed out. Color Doppler US examination strategies in patients suffering of PAOD are outlined.

Hepatic vein Doppler studies: variability of flow pattern in normal children.

Loss of triphasicity of hepatic venous flow on Doppler US has been correlated with hepatic parenchymal disease such as cirrhosis and graft rejection in adults. To document physiological variations of hepatic vein (HV) flow patterns in normal children of different age groups, the influence of age, sex, body position, site of measurements within a given vein, exercise and food intake. Also, to document the reproducibility of the Doppler US findings in the three major HVs, in order to establish the limits of normal flow against which to assess liver pathology giving rise to abnormal flow pattern. Thirty-two children, divided into four age groups: less than 1 year, 1-5 years, 5-12 years and 12-16 years, with four boys and four girls in each group, underwent repeated US examinations of their HVs. The HV flow pattern was recorded as triphasic = 4, diphasic = 3, monophasic = 2 or uninterpretable = 1 at three sites in each vein: peripheral, middle and proximal in the supine position in the fasting state. One recording was then obtained in the midportion of each vein in the sitting position, another one after exercise, then after a meal and lastly one by a second radiologist. Statistical analysis of variance was done of each variable alone, in combination two by two and three by three. HV flow pattern was different from one vein to another in the majority of the children, the right HV having the least triphasic flow. Age was highly significant, the HV flow being less triphasic in young children. Sex and position were significant for the right HV only, which was the most difficult to examine. Exercise and food intake did not change the triphasicity of flow. HV flow pattern differs with age and can differ from one HV to another within an apparently normal liver. Interpretation is generally reproducible from one radiologist to another. A difference of sex, seen mostly for the right HV, may be due to unfavourable Doppler angle and difficulty of interpretation. The site of measurements within a given vein, body position, exercise and food intake do not influence the triphasicity of HV flow.

Ultrasound of renal tumors.

Despite the limitations of US in providing a complete evaluation of renal tumors before treatment planning, initial screening, characterization of renal masses and staging of RCCs can benefit from some recent advances of the technique. One of the most relevant clinical benefits of US is the increased early detection of RCCs. Recent technical improvement of gray-scale imaging has increased US performance in the detection of small renal tumors. Combined gray-scale and color Doppler US findings may strongly suggest the histopathologic nature of a renal tumor with respect to the size, the US attenuation characteristics, and the vascular distribution of the lesion. Ultrasound contributes additional diagnostic information for differential diagnosis of some renal masses that remain equivocal at CT, including: atypical cystic lesions; solid renal tumors with poor vascularity; and angiomyolipomas with minimal fat component. Ultrasound also may provide additional diagnostic information over CT in selected cases of RCCs with venous invasion. In addition to some diagnostic and therapeutic procedures that can benefit from US guidance, intraoperative US remains the only available tool that enables to ensure renal-parenchymal-sparing surgery.

Pulsed Wave and Color Doppler US Findings of Transjugular Intrahepatic Portosystemic Shunts (TIPS)

The transjugular intrahepatic portosystemic shunt (TIPS) is an effective and relatively safe and widely accepted treatment for complications arising from portal hypertension. Shunt or hepatic vein stenosis and shunt occlusion are common short- and medium-term complications arising from the procedure, though if detected early, these conditions may be treated before the recurrence of gastrointestinal bleeding or ascites. Doppler US is a relatively inexpensive, accurate, and noninvasive method for the evaluation of shunt status.

Doppler US Findings of Vascular Complication after Liver Transplantation

Vascular complications after liver transplantation may involve the hepatic artery, and hepatic and portal veins. Arterial complications are common and significant vascular complications include thrombosis or stenosis, as well as pseudoaneurysms. Venous complications include thrombisis or stenosis of the inferior vena cana, or hepatic or portal vein. Since recent evidence has shown that emergent revascularization leads to improved graft salvage and patient survival with a relatively low rate of late biliary complications, accurate and pronpt di-agnosis of hepatic arterial complications is important. Doppler US is a relatively inexpensive, accurate, and non-invasive method of diagnosing the vascular complications which may arise from liver transplantation.

Scrotal inflammatory disease: color Doppler US findings.

A study of 45 patients with 51 cases of hemiscrotal inflammatory disease was done to determine the color Doppler ultrasonographic appearance of scrotal inflammatory disorders. The diagnosis was ultimately established by means of appropriate response to antibiotic treatment (47 cases) or surgery (four cases). In all cases, there was evidence of hyperemia: an increased number and concentration of detectable vessels in the affected portion of the scrotum. In 17 cases, the gray scale images were normal, and the only evidence of inflammation was the presence of hypervascularity. Abnormally decreased epididymal vascular resistance was detected in 14 cases of epididymitis; abnormally decreased testicular vascular resistance was detected in six cases of orchitis. Spontaneous venous flow was present in 18 patients. The authors conclude that color Doppler can demonstrate the hyperemic response to scrotal inflammatory disease and that, in the proper clinical setting, it can supplement the gray scale findings and increase diagnostic confidence.