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Purpose: To show the feasibility of a combination of the advantages of modern contrast enhanced ultrasound (CEUS) with the technique of arterioportography to achieve the highest sensitivity of all different modalities., Material and Methods: Ten patients (9 m, 1 f, age 52-73 years) with suspected hepatocellular carcinoma (HCC) in liver cirrhosis (8 ethyl toxic, 2 hepatitis) were included before transarterial chemo-embolization (TACE). In all patients during a 6-week period a double enhanced MRI (Gd-DTPA and SPIO) was performed. Before TACE a bolus <2 mL ultrasound contrast agent (SonoVue®, Bracco, Milan, Italy) was injected over a selectively placed catheter in the superior mesenteric artery (SMA) and ultrasound of the liver (2.5-4 MHz, LOGIQ 9; GE Healthcare) was performed in arterioportographic phase (US-AP). Two independent readers evaluate number, size and localisation of detected lesion in MRI and US-AP. Additional diagnostic quality of both modalities was determined using a 4-point scale (1: excellent-4: not diagnostic). Differences were analysed for significance using a t-test. Interobserver variability was calculated (κ-value)., Result: In all 10 patients (100 %) US-AP was feasible. Diagnostic quality was in all cases between 1-2 for both modalities and readers (MRI standard deviation (SD) -0.51, Sono-AP SD -0.421). US-AP detected with 33.5 vs. 24.5 lesions, significant more lesions than double enhanced MRI (p < 0.022). The interobserver variability was κ -0.965 for MRI and κ -0.898 for US-AP., Conclusion: US-AP for detection of liver lesions is feasible. Using this technique significantly more lesions in patients with hepatocellular carcinoma could be detected in comparison to MRI with liver-specific contrast agent.

Objective: Feasibility of intraarterial MR angiography of the renal arteries and comparison of the accuracy of intraarterial MR angiography with selective intraarterial digital subtraction angiography (DSA) for detection of stenoses., Materials and Methods: Ten consecutive patients (mean, 68 years) with suspected renal artery stenosis underwent a digital subtraction angiography and an intraarterial gadolinium-enhanced MR angiography, performed on a 1.5-T system. For intraarterial MR angiography 60 ml diluted contrast agent (10 ml gadodiamide in 50 ml 0.9% saline solution) was injected through a conventional angiography catheter placed in the suprarenal abdominal aorta using a flow rate of 3.5 ml/s. A three-dimensional (3D) gradient-echo sequence was performed. Differences in the quantitative measurement of stenoses of lesions between DSA and intraarterial MR angiography were evaluated by three observers. Overall impression of the intraarterial MR angiography was documented on a four-point scale (1 = excellent to 4 = poor). Interobserver variability was calculated., Results: Intraarterial MR angiography of the renal arteries was feasible in all patients (100%) with a mean overall impression of all images of 1.8 (SD: 0.71). One of 9 accessory renal arteries was not visualized with intraarterial MR angiography. The overall sensitivity/specificity for detection of significant stenoses (>or=50% stenosis) were 83%/87%. Interobserver variability of intraarterial MR angiography ranged between fair and substantial (0.359-0.622)., Conclusion: Intraarterial MR angiography of the renal arteries in humans is feasible and has an acceptable sensitivity in detecting stenoses using injections of diluted contrast agent at concentrations as low as 17%.

Purpose: Contrast harmonic ultrasound (CHI) with a linear transducer is a new diagnostic approach that allows dynamic and quantitative flow detection of tissue perfusion in microsurgery. The aim of the study was the evaluation of perfusion of the dermal and subdermal layers of microvascular tissue transplants with CHI in comparison to ICG-fluorescence angiography., Material and Method: In a prospective clinical study indocyanine-green fluorescence video angiography and contrast enhanced high resolution ultrasound (5-10 MHz; linear transducer; Logiq 9; GE) were used for evaluation of the microcirculation in 10 transplanted free parascapular flaps. Two regions were analysed, the centre of the flap and the region of the anastomosis. The perfusion patterns of both methods were compared., Results: The perfusion indexes measured by ICG-fluorescence angiography correlated very precisely in all patients with the quantitative perfusion curves of contrast-enhanced US with CHI. Two flaps with slow filling and low dye intensity showed low contrast enhancement in CHI with modified perfusion curves with slow increase. In two cases a reduced perfusion and filling were found. There were no statistical differences between the two diagnostic methods (p>0.01)., Conclusion: CHI improves US detections of dermal and subdermal microcirculation in comparison to ICG fluorescence angiography. CHI is a new diagnostic method for postoperative monitoring of free flaps.