Clinical Hemorheology and Microcirculation - Volume 64, issue 3

Authors: Rübenthaler, J. | Paprottka, K.J. | Marcon, J. | Reiser, M. | Clevert, D.A.

Article Type: Research Article

Abstract: Ultrasound is a common and established imaging method for the initial characterization of renal lesions. The widespread used Bosniak classification (I–IV) classifies renal lesions in five individual groups using contrast-enhanced computer tomography (CE-CT), magnetic resonance imaging (MRI) and/or contrast-enhanced ultrasound (CEUS) imaging criteria. For complex pathologies, CEUS/MRI image fusion is a novel imaging technique for the differentiation of benign and malignant renal lesions. Compared to CE-CT and MRI alone, ultrasound image fusion offers the additional possibility of being a real-time imaging technique that can be used together with other cross-sectional imaging techniques. This article describes the newest possibilities of …image fusion with CEUS and MRI in detection and characterization of unclear renal lesions. Show more

Keywords: Renal lesions, bosniak classification, contrast-enhanced ultrasound, image fusion

DOI: 10.3233/CH-168116

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 457-466, 2016

Authors: Rübenthaler, J. | Paprottka, K.J. | Hameister, E. | Hoffmann, K. | Joiko, N. | Reiser, M. | Clevert, D.A.

Article Type: Research Article

Abstract: PURPOSE: To evaluate the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) and computed tomography (CT) in the diagnosis of malignancies after liver transplantation. MATERIALS AND METHODS: A total of 23 patients with suspicious liver masses after liver transplantation with initial imaging series between September 2006 and September 2015 were statistically analysed. CEUS and CT were compared in their diagnosis of malignancy with CT being the gold standard. Out of 23 patients 9 patients showed malignant masses in CT, which could also be detected in 7 out 9 of cases using CEUS. RESULTS: CEUS showed a …sensitivity of 77.8%, a specificity of 100.0%, a positive predictive value (PPV) of 100.0% and a negative predictive value (NPV) of 87,5% in comparison with CT being the gold standard. In 2 cases CT showed a malignancy, contrary to the CEUS examination that was reported as normal. CONCLUSION: CEUS seems to be an alternative option for the evaluation of malignant masses in liver transplant patients. CEUS shows a high specificity and PPV in the detection of malignant liver masses. Show more

Keywords: Contrast-enhanced ultrasound (CEUS), computed tomography (CT), liver transplantation, malignancy

DOI: 10.3233/CH-168117

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 467-473, 2016

Authors: Rübenthaler, J. | Paprottka, K.J. | Hameister, E. | Hoffmann, K. | Joiko, N. | Reiser, M. | Clevert, D.A.

Article Type: Research Article

Abstract: PURPOSE: To compare the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) and computed tomography (CT) in the diagnosis of vascular complications after liver transplantation in the postoperative phase. MATERIALS AND METHODS: A total of 60 patients with elevated liver function tests after liver transplantation with initial imaging studies between July 2005 and November 2015 were retrospectively analysed. CEUS and CT were compared in their diagnosis of vascular complications and CT was considered as the gold standard. Out of 60 patients 28 patients showed vascular complications in CT, which could also be detected in 25 out 28 of …cases using CEUS. Diagnostic accuracy was tested by using the CT diagnosis as the gold standard. RESULTS: CEUS showed a sensitivity of 89.3%, a specificity of 100.0%, a positive predictive value (PPV) of 100.0% and a negative predictive value (NPV) of 91,4% compared to CT as the gold standard. In 3 cases CT showed a vascular complication, whereas the CEUS examination was reported as normal. CONCLUSION: CEUS is a fast, non-ionizing imaging modality for the initial exclusion of vascular complications after liver transplantation. CEUS shows a high specificity and PPV in the detection of vascular complications. In unclear cases CT still is considered as the gold standard. Show more

Keywords: CEUS, contrast-enhanced ultrasound, CT, liver transplantation, vascular complication

DOI: 10.3233/CH-168118

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 475-482, 2016

Authors: Pregler, B. | Beyer, L.P. | Wiesinger, I. | Nießen, C. | Jung, E.M. | Stroszczynski, C. | Wiggermann, P.

Article Type: Research Article

Abstract: PURPOSE: To assess the value of dynamic contrast enhanced ultrasound (CEUS) for the detection of residual tumor tissue day 1 after microwave ablation (MWA) of large hepatocellular carcinoma (HCC) compared to MRI. MATERIAL AND METHODS: 30 consecutive patients (5 females, 25 males, mean age 64 years, age range 54–73 years) with an untreated HCC lesion larger than or equal to 3 cm underwent percutaneous MWA between 03/2014 and 04/2016. 1 patient was excluded because of an artificial pacemaker. All remaining 29 patients underwent 3-T MRI with liver-specific contrast agent and CEUS 1 day after ablation to detect residual …tumor tissue. The 6-week follow-up including CEUS and MRI was defined as the reference standard. RESULTS: Complete ablation was achieved in 23 of 29 treated lesions (79%). The sensitivities and specificities for the detection of residual tumor tissue on day 1 were 100% and 83% for CEUS and 87% and 67% for MRI resp. without the differences being statistically significant. CONCLUSION: CEUS allows a reliable assessment of therapeutic success of percutaneous ablation of large HCC lesions one day after the ablation. Its ability to visualize reactive periablation perfusion changes in real-time might be of advantage in the depiction of residual tumor tissue when compared to MRI imaging alone. Show more

Keywords: Contrast-enhanced ultrasound (CEUS), microwave ablation (MWA), hepatocellular carcinoma (HCC), imaging findings

DOI: 10.3233/CH-168113

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 483-490, 2016

Authors: Gemeinhardt, Ole | Poch, Franz G.M. | Hiebl, Bernhard | Kunz-Zurbuchen, Urte | Corte, Giuliano M. | Thieme, Stefan F. | Vahldiek, Janis L. | Niehues, Stefan M. | Kreis, Martin E. | Klopfleisch, Robert | Lehmann, Kai S.

Article Type: Research Article

Abstract: BACKGROUND: Continuing research ex vivo and in vivo with animal models is performed to advance the oncological safety of radiofrequency ablation (RFA) of liver tumors. In these experiments, frequently imaging modalities (e.g. MRI or CT) or macro-morphological measurements are used to determine the full extent of the different ablation zones inside of RFA lesions. However, no systematic study has been performed so far, which verified the accuracy of the macro-morphological findings. Therefore, the present study aimed to correlate histological and gross pathological findings of bipolar radiofrequency ablation zones of porcine livers with regard to cell viability in …vivo . METHODS: Bipolar RFA was performed in the liver of anaesthetized female domestic pigs under CT-guidance using an internally cooled 20 mm RFA applicator. Afterwards RFA cross sections of the liver were made in a perpendicular orientation to the applicator. Ablation zones were initially documented by photography and thereafter prepared for histological analysis. Latter was based on HE-staining and NADH-diaphorase cell viability staining. Micro- and macro-morphological sections were digitally analyzed along the cross-section area for statistical correlation. RESULTS: Three different RF ablation zones could be differentiated. A central zone showing no cell viability (white zone) was surrounded by a red zone. The red zone could be divided into an inner zone of viable and non-viable cells (red zone 1), followed by a zone of edema with mostly viable cells (red zone 2). Micro- and macro-morphological data showed a strong correlation for the white zone (r  = 0.95, p  < 0.01), the red zone 1 (r  = 0.85, p  < 0.01), and the red zone 2 (r  = 0.89, p  < 0.01). CONCLUSION: White zone and red zone could clearly be distinguished in gross pathology and histology after bipolar RFA of porcine liver tissue in vivo . The red zone could be differentiated into an inner zone of viable and non-viable cells and an outer zone with high cell viability and intercellular edema. A strong correlation of micro- and macro-morphology could be shown for all three ablation zones. With this knowledge, gross pathological examination can be used as a reliable indicator of lethally damaged tissue in bipolar RFA of in vivo porcine liver. Show more

Keywords: Liver, animal model, radiofrequency ablation (RFA), bipolar, viability staining, NADH-diaphorase

DOI: 10.3233/CH-168123

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 491-499, 2016

Authors: Beyer, L.P. | Pregler, B. | Nießen, C. | Michalik, K. | Haimerl, M. | Stroszczynski, C. | Jung, E.M. | Wiggermann, P.

Article Type: Research Article

Abstract: PURPOSE: Irreversible electroporation (IRE) is a focal non-thermal ablation technique that can be used to treat prostate cancer (Pca). The objective was to document the evolution of the volume of the prostate gland and the ablation zone after IRE of Pca. MATERIAL AND METHODS: A retrospective analysis of the image findings of CEUS 1 day, 6 weeks, 3 months and 6 months after IRE of 25 patients was conducted. The prostate gland volumes and the size of the ablation zones were documented. Changes in volume and size over time were calculated. RESULTS: There was a …significant volume reduction of the prostate gland in the first 3 months after ablation. The mean percentage change after 6 weeks was 34.3% with another decrease of 35.0% after 3 months. Volume did not change between month 3 and 6. Size of ablation zone measured in short- and long-axis significantly diminished until 6 months after ablation. CONCLUSION: CEUS showed a significant involution of the prostate gland during the first 3 months and a significant decrease of the ablation zone during the first 6 months after IRE of prostate cancer. Show more

Keywords: Contrast-enhanced ultrasound (CEUS), irreversible electroporation (IRE), prostate cancer, imaging findings

DOI: 10.3233/CH-168125

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 3, pp. 501-506, 2016