Quantitative assessment of synovial vascularity using contrast-enhanced power Doppler ultrasonography: correlation with histologic findings and mr imaging findings in arthritic rabbit knee model

OBJECTIVE: To validate contrast-enhanced power Doppler ultrasonography (PD US) for the evaluation of synovial vascularity in an arthritic rabbit knee model in correlation with MR and histological findings. MATERIALS AND METHODS: Power Doppler ultrasonography was performed for carrageenin-induced arthritic left knee and control right knee of 13 rabbits, first without and then with sonic contrast agent enhancement (Levovist, Schering, Berlin Germany), followed by gadolinium-enhanced MR imaging. Synovial vascularity was quantitatively assessed by calculating the color pixel area in power Doppler sonography using a computer-aided image analysis program and by grading the enhancement on MR images: grade 1, enhancement of knee joint is less than one-third of the area; grade 2, one-third to two-thirds enhancement; and grade 3, more than two-thirds enhancement. Microvessel density (MVD) was measured on slides stained immunohistochemically for CD31 antigen for histological assessment. RESULTS: The mean area of color pixels in PD US changed from 4.37 to 16.42 mm(2) in the arthritic knee after enhancement (p < 0.05), whereas it changed from 0.77 to 2.31 mm(2) in the control knee (p < 0.05). Arthritic knees had greater power Doppler signal than control knees both before and after contrast administration (p < 0.05). The average MVD was 88 in arthritic knees and 46 in control knees. MVDs correlated with color pixel areas of contrast-enhanced power Doppler imaging in arthritic knees. In MR grading of arthritic knees, five were grade 2 and eight were grade 3. MVD and PD US revealed no significant difference between grade 2 and 3 arthritic knees (p > 0.05). CONCLUSION: Sonic contrast-enhanced PD US improves the visualization of synovial vascularity and allows quantitative measurement in experimentally induced rabbit arthritic knees.     

Contrast-enhanced power Doppler US in the diagnosis of acute appendicitis

INTRODUCTION/OBJECTIVE: To determine the value of power Doppler (PD) ultrasonography (US) and contrast-enhanced power Doppler (CEPD) US in the diagnosis of acute appendicitis and the prediction of histopathologic stages. METHODS AND MATERIAL: 50 patients with suspected acute appendicitis were evaluated by the same radiologist with PD US and CEPD US. Air micro bubbles stabilized by a granulate of "galactose and palmitic acid" were used as a contrast medium for sonography with the concentration of 400 mg/ml. PD US and CEPD US results were later correlated with the surgical and histopathologic findings. PD US and CEPD US findings were considered positive for appendicitis; if there was depiction of hyperemia in the wall of the appendix or if there was depiction of prominent peripheral vascularity when compared with normal soft tissues; and negative if both hyperemia and peripheral hyperemia were not prominent. RESULTS AND DISCUSSIONS: Of the 50 patients, 35 patients had histopathologically proven acute appendicitis. CEPD US showed prominent hyperemia in the appendiceal vessels or feeding vessels of the inflamed appendix, and resistance index (RI) calculations were easier. There was statistically significant difference between mean RI values of the normal appendix, suppurative appendicitis and gangrenous appendicitis. PD US has accuracy of 80%, sensitivity of 74% and CEPD US has 98%, and 100% in the diagnosis of acute appendicitis. CEPD US identified 100% of suppurative appendicitis and gangrenous appendicitis. CONCLUSION: CEPD US is a promising method in the diagnosis of acute appendicitis and determination of the inflammation stage.     

Vascularity of hepatocellular carcinoma: assessment with contrast-enhanced second-harmonic versus conventional power Doppler US

PURPOSE: To compare contrast material-enhanced harmonic power Doppler ultrasonography (US) with conventional power Doppler US in depicting the vascularity of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Twenty patients with nodular HCCs (2.6-13.2 cm in diameter; mean diameter, 4.8 cm) were prospectively examined with both conventional and harmonic power Doppler US. US was performed with a 2-4-MHz curved linear-array transducer according to a standard examination protocol (1,000-Hz pulse repetition frequency, medium wall filter, and power gain of 55%-84% for conventional power Doppler US; 700-Hz pulse repetition frequency, low wall filter, and power gain of 95%-98% for harmonic power Doppler US). Serial, dynamic scans were obtained before intravenous injection of the contrast agent (SH U 508A) and at 30, 60, 90, 120, 180, 240, and 300 seconds after injection with both techniques. RESULTS: The number of intratumoral power Doppler US signals was similar with both techniques at 30-90 seconds after contrast agent injection; however, after 90 seconds, conventional power Doppler US depicted significantly more signals than did harmonic power Doppler US. Harmonic power Doppler US was superior to conventional power Doppler US in terms of power Doppler artifacts such as "blooming" or motion-related artifacts. CONCLUSION: Although the effective enhancement duration is relatively short compared with that for conventional power Doppler US, contrast-enhanced harmonic power Doppler US can be effective in evaluating the vascularity of HCCs because of the advantage of fewer power Doppler artifacts.     

Ultrasound and power Doppler evaluation of the hand and wrist in patients with psoriatic arthritis

Purpose: To evaluate the ability of high-resolution and power Doppler sonography in detecting joint and tendon abnormalities in patients with psoriatic arthritis (PsA) of the hands and wrists compared with clinical and radiological findings.

Material and Methods: Thirty-six patients with psoriatic arthritis of the hands and wrists and 10 healthy controls were examined with ultrasound (US). The degree of synovial proliferation, tenosynovitis, presence of joint effusion as well as the vascularity of synovial tissue was estimated. US findings were scored using a newly devised scoring system.

Results: Thirty-two patients had articular synovial proliferation and/or tenosynovitis/tendinitis or joint effusion in one or more joints according to US. Twenty-two patients had tendon changes; only five had joint effusion. The synovial, Doppler, and total articular-teno scores were all significantly correlated to the number of swollen joints. The scores, however, did not correlate to other clinical or laboratory measurements of disease activity.

Conclusion: US proved effective in demonstrating PsA involvement of the hands and wrists and was more sensitive than clinical examination in detecting pathology. Long-term follow-up studies are needed to evaluate whether this can change the traditional approach for assessing involvement of joints and tendons in PsA.     

Radio-frequency ablation of VX2 rabbit tumors: assessment of completeness of treatment by using contrast-enhanced harmonic power Doppler US

PURPOSE: To assess contrast material-enhanced harmonic power Doppler and fundamental color Doppler ultrasonography (US) in the detection of residual viable tumor tissue after radio-frequency (RF) ablation in tumors embedded in fat. MATERIALS AND METHODS: Twenty-eight VX2 tumors were implanted into the retroperitoneum of 14 rabbits. Tumors were examined with contrast-enhanced fundamental color Doppler US and harmonic power Doppler US before and 10 minutes after RF ablation. Saline-enhanced RF ablation (30 mL/h) was performed over 10 minutes with 28-W RF power. Follow-up included repeat US examinations. Necropsies and histopathologic assessment were performed after detection of residual untreated tumor at US or 3 weeks after ablation. RESULTS: VX2 tumors reached a mean size of 21 mm +/- 9 (SD) (size range, 6-43 mm) 25 days after implantation. All tumors larger than 31 mm showed signs of central necrosis at US. Before ablation, intense vascularity was detected in all tumors with both contrast-enhanced US modes. Histopathologic assessment at the end of the follow-up period revealed local relapses due to incomplete ablation in 14 (50%) of 28 cases. Detection of residual tumor was missed in all cases with contrast-enhanced color Doppler US. Contrast-enhanced harmonic power Doppler US depicted residual flow in 12 of the 14 cases (sensitivity, 86%) in which local relapses occurred. There was a significant (P <.005, McNemar test) improvement in detection of residual tumor when the harmonic power Doppler mode was used. CONCLUSION: Contrast-enhanced harmonic power Doppler US has greater sensitivity than contrast-enhanced color Doppler US for detecting residual VX2 tumor following ablation. Therefore, contrast-enhanced harmonic power Doppler US may be a useful additional method for the detection of residual tumors after RF ablation.     

Nonpalpable breast lesions: evaluation with power Doppler US and a microbubble contrast agent-initial experience

PURPOSE: To evaluate power Doppler ultrasonography (US) performed with a microbubble US contrast agent in the differentiation of nonpalpable breast lesions. MATERIALS AND METHODS: Fifty nonpalpable breast lesions in 50 patients were prospectively evaluated with power Doppler US before and after injection of the contrast agent SH U 508A. Lesion vascularity and the morphology of vessels on US scans were analyzed and were correlated with histologic results. RESULTS: Surgical excision revealed 22 cancers and 28 benign lesions. At nonenhanced power Doppler US, eight (36%) of 22 cancers and four (14%) of 28 benign lesions were vascular. At contrast agent-enhanced power Doppler US, 21 (95%) cancers and six (21%) benign lesions were vascular (P <.001). Irregular vessels were seen in three cancers and one benign lesion at nonenhanced power Doppler US and in 11 cancers and one benign lesion at contrast-enhanced power Doppler US. By using the presence of vascularity in the mass as the diagnostic criterion for malignancy, the sensitivity, specificity, and positive and negative predictive values of power Doppler US changed from 36%, 86%, 67%, and 63%, respectively, to 95%, 79%, 78%, and 96% after contrast agent injection. CONCLUSION: Contrast-enhanced power Doppler US was superior to nonenhanced power Doppler US in the demonstration and characterization of tumor vascularity in nonpalpable breast lesions. Contrast-enhanced power Doppler US may be useful for the differentiation between nonpalpable breast cancers and benign tumors.     

Quantified power Doppler US of tumor blood flow correlates with microscopic quantification of tumor blood vessels

P:URPOSE: To evaluate the ability of a quantified power Doppler ultrasonography (US) system to help quantitate differences in tumor vascularity after radiation therapy and administration of tumor necrosis factor (TNF). MATERIALS AND METHODS: Murine glioblastoma tumors were grown in the thighs of two sets of 25 mice each. Each mouse was assigned to one of four treatment groups: control (no treatment), radiation therapy, TNF therapy, or combination therapy (both radiation and TNF therapies). Mice were then evaluated with quantified power Doppler US, and a vascularity index (color area) was calculated for different tumor regions in each group. The tumors were then excised, and histologic evaluation was performed by using an immunofluorescence-tagged monoclonal antibody against blood vessel endothelium. The number of stained blood vessels per high-power field was correlated with the sonographically determined vascularity index. RESULTS: The color area of the total tumor decreased to 37% of that in the control group in mice treated with radiation therapy alone (P: =.02), 26% of that in the control group in mice treated with TNF alone (P: =.05), and 8% of that in the control group in those treated with both TNF and radiation (P: =.006). These results correlated well with the quantified results from immunofluorescent staining (r = 0.98). CONCLUSION: Quantified power Doppler US is a noninvasive method for the evaluation of tumor vascularity and blood flow.     

Rheumatoid hand joint synovitis: gray-scale and power Doppler US quantifications following anti-tumor necrosis factor-alpha treatment: pilot study

PURPOSE: To evaluate by using B-mode and power Doppler ultrasonography (US) and clinical assessment the response of hand joint synovitis in patients with active rheumatoid arthritis (RA) to treatment with the anti-tumor necrosis factor-alpha agent infliximab. MATERIALS AND METHODS: Wrists, metacarpophalangeal (MCP) joints, and proximal interphalangeal (PIP) joints in 11 patients with active RA were assessed before and 6 weeks after three infliximab infusions. US assessment was performed at a single site in the MCP and PIP joints and at two sites (radiocarpal and intercarpal) in the wrists. Twenty measurements were performed in the wrists; 110 measurements, in the MCP joints; and 103 measurements, in the PIP joints. Two wrists and seven PIP joints were excluded owing to complete joint destruction. US parameters (synovial thickness, number of US-positive joints [ie, with synovial thickness > or = 1 mm], cumulative synovial thickness index, and presence of Doppler signal) and clinical parameters (swollen joint count) were independently assessed and compared with baseline values by using the McNemar chi2 and paired Student t tests. RESULTS: After infliximab treatment, there was a significant decrease in the mean numbers of swollen and US-positive joints and in the cumulative synovial thickness (P <.05). The mean synovial thickness decreased in all joints swollen at baseline and in the MCP and PIP joints not swollen at baseline (P <.01). Change from baseline cumulative synovial thickness correlated significantly with change in disease activity score (r = 0.69, P <.05). The number of positive Doppler US signals decreased significantly (in 13 US-positive joints at baseline, in five after treatment; P <.05). CONCLUSION: US is a feasible imaging modality for measurement of the response of RA small-joint synovitis to therapy.     

Testicular tumors: findings with color Doppler US.

A study of 28 patients with surgically proved testicular tumors was performed to determine the appearance at color Doppler ultrasound (US) scanning. There was a general correlation of tumor size and vascularity. Twenty of 21 (95%) tumors larger than 1.6 cm were hypervascular. Six of seven (86%) tumors smaller than 1.6 cm were hypovascular. One small, 1.1-cm-diameter seminoma was hypervascular, and one 2.8-cm-diameter seminoma was hypovascular. The histologic findings of the tumor did not correlate with the vascularity of the lesion as seen at color Doppler US. Resistive indexes ranged from .476 to 1.0 (mean, 0.70). Peak systolic velocities ranged from 8.4 cm/sec to 64.9 cm/sec (mean, 9.8 cm/sec). Venous flow was detected in eight tumors. The gray-scale findings, as well as history and physical examination findings, correctly suggested a neoplasm in all cases. The findings at color Doppler US were prospectively interpreted as indicative of neoplasm in 27 cases and as indicative of inflammation in one case. The authors conclude that color Doppler US scanning has only a limited role in the evaluation of testicular tumors.     

Tumor vascularity: evaluation in a murine model with contrast-enhanced color Doppler US effect of angiogenesis inhibitors

PURPOSE: To determine the ability of contrast material-enhanced ultrasonography (US) to depict tumor growth and vascularity in a murine model of prostate carcinoma treated with an angiogenic inhibitor. MATERIALS AND METHODS: Thirty-five genetically engineered mice with spontaneously occurring prostate tumors were monitored on a weekly basis with gray-scale and color Doppler US with a 15-MHz linear transducer. Eighteen mice were treated with an adenoviral vector to deliver a soluble form of the Flk1 receptor (VEGFR-2), a vascular endothelial growth factor receptor designed to block tumor angiogenesis. The remaining 17 animals were injected with saline and used as controls. Tumor volumes were calculated on the basis of serial US measurements. Color Doppler US was performed in every tumor before and after intravenous injection of 0.1 mL per kilogram of body weight of a US contrast agent. US images were evaluated for tumor size, pattern of vascularity, and extent of vascularity (vascularity index). Findings at US were correlated with findings at autopsy in 30 animals. RESULTS: Estimates of tumor volume at US correlated well with tumor measurements at autopsy (r =.89, P <.001). Marked differences in tumor size and slope of increasing tumor volume were evident at US between treated and control mice after treatment (P <.016, analysis of variance). The US contrast agent markedly increased color Doppler US signal intensity with an 800% (from 10% to 12,700%) change in the mean number of color pixels per imaging field, and showed vascularity in areas of tumor not identified on precontrast images in 70% (109 of 156 studies). No correlation was found between the pattern of vascularity or vascularity index before or after contrast material administration and tumor size, treatment status, or histologic assessment of tumor vascularity. CONCLUSION: Contrast-enhanced US improves visualization of tumor vascularity. However, histologic patterns of tumor vascularity do not correlate with Doppler US depiction of blood flow in these vessels.     

Hepatocellular carcinoma: depiction of tumor parenchymal flow with intermittent harmonic power Doppler US during the early arterial phase in dual-display mode

PURPOSE: To assess the effectiveness of contrast material-enhanced intermittent harmonic Doppler ultrasonography (US) in depicting tumor vessels and tumor parenchymal flow (stain) in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Fifty-eight patients with 65 HCC nodules were examined by using intermittent harmonic power Doppler US and digital subtraction harmonic B-mode US, both with intravenous administration of SH U 508A. Vascular findings at early arterial phase harmonic US were classified as positive enhancement or nonenhancement, depending on the tumor vascularity relative to the surrounding liver parenchyma. These results were compared with those of three-phase helical dynamic computed tomography (CT). RESULTS: For hypervascular HCCs, there was excellent depiction of tumor vessels and tumor stain with the two intermittent harmonic US methods. The sensitivity and specificity for depiction of tumor vascularity were 93% (41 of 44 nodules) and 100% (21 of 21), respectively, with intermittent harmonic power Doppler US and 86% (38 of 44) and 100% (21 of 21), respectively, with subtraction US, as compared with these values at dynamic CT. Attenuation was an important factor in the depictability of tumor vascularity at harmonic US. CONCLUSION: Contrast-enhanced intermittent harmonic US enables noninvasive demonstration of tumor vessels and especially tumor stain in HCC.     

Acute pyelonephritis: comparison of diagnosis with 99mTc-DMSA, SPECT, spiral CT, MR imaging, and power Doppler US in an experimental pig model

PURPOSE: To compare the sensitivity and specificity of technetium-99m dimercaptosuccinic acid (DMSA) single photon emission computed tomography (SPECT), spiral computed tomography (CT), magnetic resonance (MR) imaging, and power Doppler ultrasonography (US) for the detection and localization of acute pyelonephritis by using histopathologic findings as the standard of reference. MATERIALS AND METHODS: Bilateral vesicoureteric reflux was surgically created in 35 piglets (70 kidneys). One week later, a liquid bacterial culture of Escherichia coli was injected into the bladder. Three days after induction of urinary infection, imaging studies were performed, and the kidneys were removed for histopathologic examination. SPECT images were obtained 2-3 hours after injection of 99mTc-DMSA. Transverse and coronal MR images were obtained with gadolinium-enhanced fast inversion recovery. Transverse CT images were obtained before and after injection of contrast agent. Power Doppler US was performed in longitudinal, transverse, and coronal planes. Each kidney was divided into three zones for correlation of findings. RESULTS: Histopathologic examination revealed pyelonephritis in 102 zones in 38 kidneys. Sensitivity and specificity for detecting pyelonephritis in the kidneys were 92.1% and 93.8% for SPECT, 89.5% and 87.5% for MR imaging, 86.8% and 87.5% for CT, and 74.3% and 56.7% for US. Sensitivity and specificity for detecting pyelonephritis in the zones were 94.1% and 95.4% for SPECT, 91.2% and 92.6% for MR imaging, 88.2% and 93.5% for CT, and 56.6% and 81.4% for US. The pairwise comparison of these modalities showed no statistically significant difference among them except for US. CONCLUSION: 99mTc-DMSA SPECT, spiral CT, and MR imaging appear to be equally sensitive and reliable for the detection of acute pyelonephritis; power Doppler US is significantly less accurate.     

Assessment of enthesitis in ankylosing spondylitis by power Doppler ultrasonography

Objective To evaluate the relationship between power Doppler ultrasonography (PDUS) assessment and clinical variables including enthesitis index, pain threshold and disease activity parameters, and to document grey-scale US findings of the 13 entheses examined.Design and patients A total of 390 entheses were examined in thirty patients with AS, and clinical variables of the Maastricht Ankylosing Spondylitis Enthesitis Index (MASES), anthropometric measurements, disease activity and functional parameters were documented. A total MASES score by palpation (t-PS) and algometric pressure pain threshold (t-PPT) was obtained. Grey scale and PDUS examination of 13 entheses were performed. Grey-scale changes such as altered tendon echogenity, calcification, cortical reactive changes and bursitis were noted, and flow on PDUS was graded semi-quantitatively.Results Cumulative power Doppler (t-PDS) score significantly correlated with t-PS and t-PPT. Ultimate correlations were found between power Doppler scores and pain, disease activity and disability parameters. Changes in grey scale combined with PDUS were more prevalent in lower-extremity entheses. The intraobserver agreement of flow signal grading was excellent (kappa=0.82). Clinical and sonographic results were concordant for three regions, but were discordant for four regions where tenderness was accepted as the sole clinical manifestation of enthesis.Conclusion Pain or tenderness is associated with increased vascularity of entheses. Power Doppler US examination of the entheses may be useful and complementary to the clinical evaluation, and further research is needed to assess its role in diagnosis and follow-up of disease course.     

From donor to recipient. Doppler US, power US and scintigraphy of kidney perfusion before and after transplantation

PURPOSE: To follow kidneys from the donor to the recipient by assessing whether perfusion changes occur by using duplex Doppler US, power Doppler US and scintigraphy. MATERIAL AND METHODS: The prospective study included 12 donors and their corresponding 12 recipients. For each donor, both donor kidneys were evaluated by duplex Doppler US, power Doppler US and scintigraphy 1 day before surgery. The same procedure was carried out on the renal allografts at days 1, 3, 5 and months 1 and 3 post-transplantation. Power Doppler findings were classified according to a grading system of 1 to 4. Resistive indices (RIs) were determined based on interlobar and segmental arterial flow. Peak systolic velocity and RIs of the main renal artery were also measured. A perfusion parameter named the peak-to-plateau ratio was calculated. Statistical analysis was performed using the paired-samples t-test. RESULTS: Intrarenal RI elevation and decreased renal artery peak systolic velocity was observed in normally functioning recipient kidneys. CONCLUSION: Duplex Doppler sonography demonstrated that transplanted kidneys had an increase in intrarenal vascular resistance at 1 month and a decrease in renal artery peak systolic velocity at 3 months post-transplantation. Scintigraphy and power Doppler US did not reveal any statistically significant perfusion change in normally functioning kidneys from donor to recipient.     

Evaluation of testicular viability by power Doppler ultrasonography in experimentally induced acute testicular torsion

RATIONALE AND OBJECTIVE: We sought to determine whether torsed testis viability can be evaluated by ultrasonography (US) including power Doppler US in an experimental model of acute testicular torsion. METHOD: Eighteen rats underwent unilateral 540 degrees testicular torsion and contralateral orchiopexy. Gray-scale and power Doppler US were performed 24 hours later. We evaluated echogenicity, intratesticular vascular flow, and testis size. Echogenicity and intratesticular vascular flow were quantitatively analyzed by using a visual scale and computer-based analysis. After US, detorsion was performed in torsed testes, and 6 days after detorsion testes were excised to determine testicular viability, which was determined using gross and microscopic findings. US findings before detorsion were correlated with testicular viability. RESULTS: At US performed 24 hours after testicular torsion, all viable testes (n = 7) were homogeneous and isoechoic versus contralateral testes. In nonviable testes (n = 11), lower (82%) and heterogeneous (73%) echogenicities were seen on gray-scale US. Intratesticular vascular flow was preserved in 86% of viable testes. In nonviable testes, no intratesticular vascularity was observed in 82%, and intermittent, peripheral blood flow was detected in the remaining 18%. Intratesticular focal lesions were observed in 45% of nonviable testis. Quantitative analysis showed a statistically significant difference between viable and nonviable testes in terms of testicular echogenicity and intratesticular vascular flow. CONCLUSION: Preoperative US including power Doppler examination can predict testicular viability in testicular torsion. Echogenicity of nonviable testes was found to be hypoechoic and inhomogeneous. Power Doppler examination showed no or intermittent peripheral blood flow in nonviable testes.     

Correlation of power Doppler with microvessel density in assessing prostate needle biopsy

AIM: To correlate hypervascular power Doppler ultrasonography with the histological evaluation of microvasculature in the prostate using trans-rectal ultrasound (TRUS)-guided needle biopsy. MATERIALS AND METHODS: Ninety-six patients with a lower urinary tract symptoms (LUTS) and prostate specific antigen (PSA) value more than 4 ng/ml were evaluated using power Doppler ultrasonography before biopsy. The vascularity of the peripheral zone was graded on a scale of PZ0 to PZ2. Core needle biopsies were immunostained with CD31(DAKO) and counting was performed manually on separate high power fields (HPF; x 400) in areas containing the highest number of vessels. RESULTS: There was a significant correlation between the grading system used for power Doppler and the microvessel density (MVD; PZ0 28.61 +/- 8.97,PZ1 36.00 +/- 12.11 & PZ2 64.008 +/- 15.86; p < 0.001). There was also a significant difference in MVD between benign, malignant and tissue cores with atypia and prostatic intra-epithelial neoplasia (PIN; p < 0.001 and p < 0.018 respectively). There was a significant correlation between malignant tissue having a higher Gleason score and increased MVD (p < 0.001) Furthermore, cancer biopsies having a high flow PZ2 are nearly twice as likely (63.2%) to have a Gleason score of 7 or more when compared those having a Gleason score of less than 7 (36.8%). CONCLUSION: The grading system of assessing the power Doppler flow signals appears to be of value as an indicator of MVD. It also correlates with a higher Gleason score and this may reflect the clinical outcome in prostate cancer. It deserves further study and evaluation as a prognostic indicator.     

Diagnostic utility of an echo-contrast agent in patients with synovitis using power Doppler ultrasound: a preliminary study with comparison to contrast-enhanced MRI

The purpose of this study was to first evaluate Levovist (Schering, Berlin, Germany), an echo-contrast agent, during power Doppler sonography (PDS) in patients with synovitis using asymptomatic joints as controls. Then we evaluated the accuracy of this technique against contrast-enhanced MRI. Forty patients (19 men and 21 women; mean age 40 years) were enrolled on the basis of clinical signs, laboratory tests, and radiographic findings positive for articular inflammatory disease. They were examined with conventional ultrasonography (US) and PDS techniques before and after intravenous contrast medium injection. Fourteen patients then underwent MRI with and without contrast medium 8–14 days after PDS studies. Three expert readers independently evaluated each examination. After contrast medium, synovium in inflammatory arthritis enhanced on PDS compared with normal joints in the same patient. Power Doppler sonography after contrast medium and MRI were concordant in all cases. Power Doppler sonography with contrast medium showed a qualitative increase in signal from synovial vessels, the first sign of synovial changes in inflammatory diseases. Received: 10 February 2000 Revised: 27 July 2000 Accepted: 1 August 2000     

High reproducibility of patellar tendon vascularity assessed by colour Doppler ultrasonography: a reliable measurement tool for quantifying tendon pathology

Background: This study examined whether patellar tendon vascularity could be quantified accurately in the clinical setting using colour Doppler ultrasonography. Methods: A sonographer and two radiologists visually estimated tendon vascularity in millimetres in 74 tendons during ultrasound (US) examination and from hard copy films. These estimates were then compared to the length of vessels measured from the digital image in millimetres and the correlation between them was determined. A subset of 16 tendons was used to compare the estimates of vascularity by two examiners at US examination. Results: The estimation of vascular length at US examination correlated highly with the measured vascular length (r = 0.92; 95% confidence interval (CI) 0.87 to 0.94), as did the length estimated from the films (r = 0.94; 95% CI 0.9 to 0.96). The correlation between examiners was 0.84 (95% CI 0.51 to 0.94) for the estimates made during US examination and 0.85 (95% CI 0.59 to 0.95) for the vessel lengths measured from the digital images. Conclusions: These excellent correlations indicate that tendon vascularity can be reliably estimated using colour Doppler ultrasonography and tendon vascularity could therefore be used by clinicians to rate clinical change. This method of quantifying tendon vascularity could also be used in research to investigate the effects of tendon treatments on vascularity.     

Doppler US in rheumatic diseases with special emphasis on rheumatoid arthritis and spondyloarthritis

Developments in digital ultrasonography (US) technology and the use of high-frequency broadband transducers have increased the quality of US imaging, particularly of superficial tissues. Thus, US, particularly color US or power Doppler US, in which high-resolution transducers are used, has become an important imaging modality in the assessment of rheumatic diseases. Furthermore, therapeutic interventions and biopsies can be performed under US guidance during the assessment of lesions. In this era of effective treatments, such as biologics, improvements in synovial inflammation in rheumatoid arthritis as well as changes in enthesitis in spondyloarthropathies, including ankylosing spondylitis and psoriatic arthritis, can be monitored effectively using gray-scale and/or power Doppler US. US is also a good imaging modality for crystal arthropathies, including gout and pseudogout, in which synovitis, erosions, tophi, and crystal deposition within or around the joint can be visualized readily. Vascular and tenosynovial structures, as well as the salivary glands, can be assessed with US in vasculitis and connective tissue disorders, including systemic lupus erythematosus and Sjögren’s syndrome. Current research is focused on improving the sensitivity, specificity, validity, and reproducibility of US findings. In this review, we summarized the role of US, particularly power Doppler US, in rheumatic diseases and inflammation in superficial tissues.Developments in digital ultrasonography (US) technology and the use of high-frequency broadband transducers have increased the quality of US imaging, particularly of superficial tissues. The increase in spatial resolution has facilitated evaluation of normal and pathological structures using US, and the increased sensitivity of color Doppler US (CDUS) for low-flow signals has enabled the evaluation of vascularity in these structures.Thus, US, particularly CDUS or power Doppler US (PDUS), in which high-resolution transducers are used, has become the primary imaging modality for superficial tissues. US can be used as a first-step screening tool to assess the presence of superficial soft tissue masses and thus can be used to evaluate the need for other imaging techniques. High-frequency US, in some cases, allows more specific diagnoses by characterizing the anatomy of the superficial tissues and flow within the lesions or neighboring tissues (1–4).Indeed, US and Doppler US can define the cystic and solid nature of lesions and thus provide a final diagnosis, in some cases without the need for another imaging modality. Furthermore, therapeutic interventions and biopsies can be performed under US guidance during the assessment of lesions. Changes in the size and vascularity of lesions, clinical responses, and local tumor recurrence can also be followed by CDUS/PDUS (1, 3). In this review, we emphasized the role of US, particularly PDUS, in rheumatic diseases and inflammation in superficial tissues.     

Dynamic flow US, color Doppler US, and power Doppler US in the assessment of vessel signals of thoracic lesions abutting pulsatile organs

RATIONALE AND OBJECTIVES: Dynamic flow ultrasound (DFUS) is a new color Doppler imaging method with better B-mode imaging and fewer blooming effects and color noises. This study was designed to compare the imaging quality of vessel signals in thoracic lesions using DFUS, color Doppler US (CDUS), and power Doppler US (PDUS). MATERIALS AND METHODS: Thirty-four patients with thoracic lesions abutting pulsatile organs [heart (n = 13), aorta (n = 14) and pulmonary artery (n = 7)] and undergoing complete chest US examinations were included to assess the imaging quality about vessel signals, blooming effect, color noise, and the influence of decision in needle biopsy between different US modes. RESULTS: Our results showed that DFUS, CDUS, and PDUS could all demonstrate the vessel signals clearly (all P > .05). However, when focusing on the blooming effect and color noise, DFUS showed the more superior imaging quality than CDUS and PDUS (all P < or = .001); and acceptable blooming effects/color noise were found with 100% (34/34)/97% (33/34), 35% (12/34)/68% (23/34), and 26% (9/34)/38% (13/34) in DFUS, CDUS, and PDUS, respectively. Especially, in the assessment of decision making for percutaneous needle biopsy, DFUS had the less influence than CDUS and PDUS (3% [1/33] versus 29% [10/34] and 3% [1/33] versus 38% [13/34], both P < .01). CONCLUSIONS: We concluded that DFUS has a clearly more superior imaging quality than CDUS and PDUS in demonstrating the vessel signals of thoracic lesions, with less blooming effect and color noise.