40 research outputs found
Diagnostic vascular ultrasonography with the help of color Doppler and contrast-enhanced ultrasonography
The use of ultrasonography and especially of contrast-enhanced ultrasonography (CEUS) in the diagnosis of vascular pathologies before and after interventions has significantly increased over the past years due to the broader availability of modern ultrasound systems with CEUS capabilities and more trained user experience in this imaging modality. For the preinterventional and postinterventional work-up of carotid diseases, duplex ultrasound as well as CEUS have been established as the standard-of-care examination procedures for diagnosis, evaluation, and follow-up. In addition to its use for carotid arterial diseases, ultrasonography has also become the primary modality for the screening of vascular pathologies. This review describes the most common pathologies found in ultrasonography of the carotid arteries, the abdominal aorta, and the femoral arteries
Contrast-Enhanced Ultrasound for Surveillance of Choroidal Carcinoma Patients: Features of Liver Metastasis Arising Several Years after Treatment of the Primary Tumor
Choroidal carcinoma is an insidious tumor frequently causing late liver metastases which are associated with a poor outcome. Since metastatic liver lesions are potentially resectable with curative intention, tight follow-up schedules after treatment of primary tumors for the early detection of liver metastasis have been proposed. The methods employed so far, however, have proven to be of limited sensitivity, and it is likely that a combined approach comprising the use of both imaging techniques and biohumoral markers will, in the future, improve the sensitivity of methods aiming at detecting liver metastasis early. Contrast-enhanced ultrasound (CEUS) is increasingly used in the clinic due to its advantage over conventional sonography for the early detection of tumor lesions and thus represents a promising accurate and cost-effective diagnostic tool. Its use for the early diagnosis of metastatic choroidal cancer has never been proposed before in the literature. Here, we describe for the first time the CEUS features of a large liver metastasis originating from choroidal cancer occurring 13 years after diagnosis in comparison to PET-CT, MRI and conventional sonography. Furthermore, we propose CEUS as a routine follow-up method for the early detection of liver metastasis of patients affected by choroidal carcinoma
Incidental Diagnosis of a Carcinoid Tumor of the Ileum using Contrast-Enhanced Ultrasound (CEUS)
Magnetic Resonance Imaging-Guided Focused Ultrasound Treatment of Symptomatic Uterine Fibroids Impact of Technology Advancement on Ablation Volumes in 115 Patients
Objectives: The aim of this study was to assess the impact of the advanced technology of the new ExAblate 2100 system (Insightec Ltd, Haifa, Israel) for magnetic resonance imaging (MRI)-guided focused ultrasound surgery on treatment outcomes in patients with symptomatic uterine fibroids, as measured by the nonperfused volume ratio. Materials and Methods: This is a retrospective analysis of 115 women (mean age, 42 years; range, 27-54 years) with symptomatic fibroids who consecutively underwent MRI-guided focused ultrasound treatment in a single center with the new generation ExAblate 2100 system from November 2010 to June 2011. Mean +/- SD total volume and number of treated fibroids (per patient) were 89 +/- 94 cm(3) and 2.2 +/- 1.7, respectively. Patient baseline characteristics were analyzed regarding their impact on the resulting nonperfused volume ratio. Results: Magnetic resonance imaging-guided focused ultrasound treatment was technically successful in 115 of 123 patients (93.5%). In 8 patients, treatment was not possible because of bowel loops in the beam pathway that could not be mitigated (n = 6), patient movement (n = 1), and system malfunction (n = 1). Mean nonperfused volume ratio was 88% +/- 15% (range, 38%-100%). Mean applied energy level was 5400 +/- 1200 J, and mean number of sonications was 74 +/- 27. No major complications occurred. Two cases of first-degree skin burn resolved within 1 week after the intervention. Of the baseline characteristics analyzed, only the planned treatment volume had a statistically significant impact on nonperfused volume ratio. Conclusions: With technological advancement, the outcome of MRI-guided focused ultrasound treatment in terms of the nonperfused volume ratio can be enhanced with a high safety profile, markedly exceeding results reported in previous clinical trials
Reducing tumor growth and angiogenesis using a triple therapy measured with Contrast-enhanced ultrasound (CEUS)
Background
To evaluate the in vivo response by detecting the anti-angiogenic and invasion-inhibiting effects of a triple-combination-therapy in an experimental-small-animal-squamous-cell-carcinoma-model using the âflash-replenishmentâ (FR) method to assess tissue hemodynamics via contrast-enhanced-ultrasound (CEUS).
Methods
Human hypopharynx-carcinoma-cells were subcutaneously injected into the left flank of 22-female-athymic-nude-rats. After seven days of subcutaneous tumor growth, FR-measurements were performed on each rat. Treatment-group and control-group were treated every day for a period of one week, with the treatment-group receiving solvents containing a triple therapy of UpamostatÂź, CelecoxibÂź and IlomastatÂź and the control-group solvents only. On day seven, follow-up measurements were performed using the same measurement protocol to assess the effects of the triple therapy. VueBoxÂź was used to quantify the kinetic parameters and additional immunohistochemistry analyses were performed for comparison with and validation of the CEUS results against established methods (Proliferation/Ki-67, vascularization/CD31, apoptosis/caspase3).
Results
Compared to the control-group, the treatment-group that received the triple-therapy resulted in a reduction of tumor growth by 48.6% in size. Likewise, the immunohistochemistry results showed significant decreases in tumor proliferation and vascularization in the treatment-group in comparison to the control-group of 26%(pâ€0.05) and 32.2%(pâ€0.05) respectively. Correspondingly, between the baseline and follow-up measurements, the therapy-group was associated with a significant(p †0.01) decrease in the relative-Blood-Volume(rBV) in both the whole tumor(wt) and hypervascular tumor(ht) areas (pâ€0.01), while the control-group was associated with a significant (pâ€0.01) increase of the rBV in the wt area and a non-significant increase (pâ€0.16) in the ht area. The mean-transit-time (mTT) of the wt and the ht areas showed a significant increase (pâ€0.01) in the follow-up measurements in the therapy group.
Conclusion
The triple-therapy is feasible and effective in reducing both tumor growth and vascularization. In particular, compared with the placebo-group, the triple-therapy-group resulted in a reduction in tumor growth of 48.6% in size when assessed by CEUS and a significant reduction in the number of vessels in the tumor of 32% as assessed by immunohistochemistry. As the immunohistochemistry supports the CEUS findings, CEUS using the âflash replenishmentâ(FR) method appears to provide a useful assessment of the anti-angiogenic and invasion-inhibiting effects of a triple combination therapy
The carotid plaque imaging in acute stroke (CAPIAS) study:
Background: In up to 30% of patients with ischemic stroke no definite etiology can be established. A significant proportion of cryptogenic stroke cases may be due to non-stenosing atherosclerotic plaques or low grade carotid artery stenosis not fulfilling common criteria for atherothrombotic stroke. The aim of the CAPIAS study is to determine the frequency, characteristics, clinical and radiological long-term consequences of ipsilateral complicated American Heart Association lesion type VI (AHA-LT VI) carotid artery plaques in patients with cryptogenic stroke. Methods/Design: 300 patients (age > 49 years) with unilateral DWI-positive lesions in the anterior circulation and non- or moderately stenosing (<70% NASCET) internal carotid artery plaques will be enrolled in the prospective multicenter study CAPIAS. Carotid plaque characteristics will be determined by high-resolution black-blood carotid MRI at baseline and 12 month follow up. Primary outcome is the prevalence of complicated AHA-LT VI plaques in cryptogenic stroke patients ipsilateral to the ischemic stroke compared to the contralateral side and to patients with defined stroke etiology. Secondary outcomes include the association of AHA-LT VI plaques with the recurrence rates of ischemic events up to 36 months, rates of new ischemic lesions on cerebral MRI (including clinically silent lesions) after 12 months and the influence of specific AHA-LT VI plaque features on the progression of atherosclerotic disease burden, on specific infarct patterns, biomarkers and aortic arch plaques. Discussion: CAPIAS will provide important insights into the role of non-stenosing carotid artery plaques in cryptogenic stroke. The results might have implications for our understanding of stroke mechanism, offer new diagnostic options and provide the basis for the planning of targeted interventional studies
Added value of randomised biopsy to multiparametric magnetic resonance imagingâtargeted biopsy of the prostate in a contemporary cohort
Objective
To assess the added value of concurrent systematic randomised ultrasonography-guided biopsy (SBx) to multiparametric magnetic resonance imaging (mpMRI)-targeted biopsy and the additional rate of overdiagnosis of clinically insignificant prostate cancer (ciPCa) by SBx in a large contemporary, real-world cohort.
Patients and Methods
A total of 1552 patients with positive mpMRI and consecutive mpMRI-targeted biopsy and SBx were enrolled. Added value and the rate of overdiagnosis by SBx was evaluated. Primary outcome: added value of SBx, defined as detection rate of clinically significant PCa (csPCa; International Society of Urological Pathology [ISUP] Grade â„2) by SBx, while mpMRI-targeted biopsy was negative or showed ciPCa (ISUP Grade 1). Secondary outcome: rate of overdiagnosis by SBx, defined as detection of ciPCa in patients with negative mpMRI-targeted biopsy and PSA level of <10âng/mL.
Results
Detection rate of csPCa by mpMRI-targeted biopsy and/or SBx was 753/1552 (49%). Added value of SBx was 145/944 (15%). Rate of overdiagnosis by SBx was 146/656 (22%). Added value of SBx did not change when comparing patients with previous prostate biopsy and biopsy naĂŻve patients. In multivariable analysis, a Prostate Imaging-Reporting and Data System (PI-RADS) 4 index lesion (odds ratio [OR] 3.19, 95% confidence interval [CI] 1.66â6.78; Pâ=â0.001), a PI-RADS 5 index lesion (OR 2.89, 95% CI 1.39â6.46; Pâ=â0.006) and age (OR 1.05, 95% CI 1.03â1.08; Pâ<â0.001) were independently associated with added value of SBx.
Conclusions
In our real-world analysis, we saw a significant impact on added value and added rate of overdiagnosis by SBx. Subgroup analysis showed no significant decrease of added value in any evaluated risk group. Therefore, we do not endorse omitting concurrent SBx to mpMRI-guided biopsy of the prostate
High resolution carotid black-blood 3T MR with parallel imaging and dedicated 4-channel surface coils
Background: Most of the carotid plaque MR studies have been performed using black-blood protocols at 1.5 T without parallel imaging techniques. The purpose of this study was to evaluate a multi-sequence, black-blood MR protocol using parallel imaging and a dedicated 4-channel surface coil for vessel wall imaging of the carotid arteries at 3 T. Materials and methods: 14 healthy volunteers and 14 patients with intimal thickening as proven by duplex ultrasound had their carotid arteries imaged at 3 T using a multi-sequence protocol (time-of-flight MR angiography, pre-contrast T1w-, PDw- and T2w sequences in the volunteers, additional post-contrast T1w- and dynamic contrast enhanced sequences in patients). To assess intrascan reproducibility, 10 volunteers were scanned twice within 2 weeks. Results: Intrascan reproducibility for quantitative measurements of lumen, wall and outer wall areas was excellent with Intraclass Correlation Coefficients >0.98 and measurement errors of 1.5%, 4.5% and 1.9%, respectively. Patients had larger wall areas than volunteers in both common carotid and internal carotid arteries and smaller lumen areas in internal carotid arteries (p < 0.001). Positive correlations were found between wall area and cardiovascular risk factors such as age, hypertension, coronary heart disease and hypercholesterolemia (Spearman's r = 0.45-0.76, p < 0.05). No significant correlations were found between wall area and body mass index, gender, diabetes or a family history of cardiovascular disease. Conclusion: The findings of this study indicate that high resolution carotid black-blood 3 T MR with parallel imaging is a fast, reproducible and robust method to assess carotid atherosclerotic plaque in vivo and this method is ready to be used in clinical practice
Reducing tumor growth and angiogenesis using a triple therapy measured with Contrast-enhanced ultrasound (CEUS)
Background
To evaluate the in vivo response by detecting the anti-angiogenic and invasion-inhibiting effects of a triple-combination-therapy in an experimental-small-animal-squamous-cell-carcinoma-model using the âflash-replenishmentâ (FR) method to assess tissue hemodynamics via contrast-enhanced-ultrasound (CEUS).
Methods
Human hypopharynx-carcinoma-cells were subcutaneously injected into the left flank of 22-female-athymic-nude-rats. After seven days of subcutaneous tumor growth, FR-measurements were performed on each rat. Treatment-group and control-group were treated every day for a period of one week, with the treatment-group receiving solvents containing a triple therapy of UpamostatÂź, CelecoxibÂź and IlomastatÂź and the control-group solvents only. On day seven, follow-up measurements were performed using the same measurement protocol to assess the effects of the triple therapy. VueBoxÂź was used to quantify the kinetic parameters and additional immunohistochemistry analyses were performed for comparison with and validation of the CEUS results against established methods (Proliferation/Ki-67, vascularization/CD31, apoptosis/caspase3).
Results
Compared to the control-group, the treatment-group that received the triple-therapy resulted in a reduction of tumor growth by 48.6% in size. Likewise, the immunohistochemistry results showed significant decreases in tumor proliferation and vascularization in the treatment-group in comparison to the control-group of 26%(pâ€0.05) and 32.2%(pâ€0.05) respectively. Correspondingly, between the baseline and follow-up measurements, the therapy-group was associated with a significant(p †0.01) decrease in the relative-Blood-Volume(rBV) in both the whole tumor(wt) and hypervascular tumor(ht) areas (pâ€0.01), while the control-group was associated with a significant (pâ€0.01) increase of the rBV in the wt area and a non-significant increase (pâ€0.16) in the ht area. The mean-transit-time (mTT) of the wt and the ht areas showed a significant increase (pâ€0.01) in the follow-up measurements in the therapy group.
Conclusion
The triple-therapy is feasible and effective in reducing both tumor growth and vascularization. In particular, compared with the placebo-group, the triple-therapy-group resulted in a reduction in tumor growth of 48.6% in size when assessed by CEUS and a significant reduction in the number of vessels in the tumor of 32% as assessed by immunohistochemistry. As the immunohistochemistry supports the CEUS findings, CEUS using the âflash replenishmentâ(FR) method appears to provide a useful assessment of the anti-angiogenic and invasion-inhibiting effects of a triple combination therapy