Non-invasive diagnosis of acute intestinal graft-versus-host disease by a new scoring system using ultrasound morphology, compound elastography, and contrast-enhanced ultrasound

Acute gastrointestinal (GI) graft-versus-host disease (GvHD) is a life-threating complication in patients after allogeneic stem cell transplantation (ASCT). In 60 sonographic analyses, a novel scoring system for non-invasive diagnosis of severe GI GvHD was developed. The score comprised morphological and vascular changes using B-mode and color-coded Doppler sonography, changes of mural stiffness using compound elastography, and dynamic microvascularisation using contrast-enhanced ultrasound (CEUS). Furthermore, inflammatory parameters such as CRP, Calprotectin, and regenerating islet-derived protein 3α (Reg3α) were obtained. ROC curve analysis of our novel GvHD sum score revealed an area under the curve of 1.0 (95% CI: 0.99-1.00) in diagnosing GI GvHD and 0.88 (95% CI: 0.79-0.96) for severe GI GvHD. A sum score above 5 correlated with GI GvHD with a sensitivity of 97.6% (41/42) and a specificity of 94.4% (17/18) and score values above 10 with severe GI GvHD with a sensitivity of 91.7% (11/12) and specificity of 79.2% (38/48). The additional use of inflammatory parameters did not improve the predictive power. CEUS is a promising, non-invasive tool for the diagnosis of acute GI GvHD. Together with further descriptive parameters for inflammatory processes, it gains significant diagnostic accuracy in identifying patients with severe stages of acute intestinal GvHD.

Evaluation of integrated color-coded perfusion analysis for contrast-enhanced ultrasound (CEUS) after percutaneous interventions for malignant liver lesions: First results

BACKGROUND

 With the rising number of percutaneous ablation therapies in malignant liver lesions there is a need of reliable diagnostics after the intervention to differentiate between reactive changes and tumor.

PURPOSE

To assess the success of percutaneous ablation therapies for malignant liver lesions using CEUS with perfusion analysis.

MATERIAL AND METHODS

Retrospective analysis of perfusion analysis for 67 patients with 94 malignant liver lesions, treated with ablation therapies. The lesions were 70 hepatocellular carcinomas (HCC), 18 metastases, 4 cholangiocellular carcinomas (CCC), 2 lesions remained unclear. CEUS was performed after bolus injection of 1.6-2.4 ml of sulfur-hexafluoride microbubbles. The perfusion analysis was calculated using Peak, TTP, mTT and AUC with integrated software during the late arterial to early portal-venous phase for approximately 9 sec (5-15 sec). For the evaluation of the success after percutaneous treatment the perfusion results were compared to the follow-up control after 6 months with CT and MRI and CEUS.

RESULTS

Perfusion analyses after percutaneous treatment of malignant liver lesions showed highly significant perfusion differences when comparing the center to the surrounding tissue and the margins (p<0.0001) for Peak and also for AUC. 62 lesions were successfully treated, meaning there was no local recurrence after 6 months. In cases of residual tumor CEUS showed a nodular marginal enhancement, the corresponding perfusion analyses showed nodular red and yellow pseudo-color shades.

CONCLUSIONS

Using CEUS and perfusion analysis, a critical analysis of post-ablation defects in malignant liver lesions is possible. With the help of pseudo-colors, remaining tumor-vascularization can be detected.

Evaluation of dynamic effects of therapy-induced changes in microcirculation after percutaneous treatment of vascular malformations using contrast-enhanced ultrasound (CEUS) and time intensity curve (TIC) analyses

The aim of this follow-up study was to demonstrate the effect of percutaneous interventional treatment on local microcirculation of peripheral vascular malformations using CEUS and TIC analysis.

MATERIAL AND METHODS

Retrospective analysis of 197 patients (136 female; 61 male; 3-86 years) with 135 venous (VM), 39 arterio-venous (AVM), 8 lymphatic and 15 veno-lymphatic peripheral vascular malformations before and after the first percutaneous treatment.CEUS was performed after i.v. injection of 1-2.4 ml of sulfur hexafluoride microbubbles (SonoVue®) using a 6-9 MHz linear probe. Digitally stored cine loops (starting in the early arterial phase for 60 sec) were read by independent readers in consensus. Regions of interest (ROI) were defined in the center and at the margins of the malformation, as well as in the healthy surrounding tissue. TIC analyses with Time to Peak (TTP) and Area under the Curve (AUC) were calculated using integrated perfusion software.

RESULTS

After the treatment there was a significant decrease for median AUC in VM in the center from 297.8 (14.5-2167.6) rU down to 243.3 (0.1-1678.8) rU (p = 0.043) and in the surrounding tissue down to 107.7 (20.2-660.2) rU (p = 0.018). For the other malformations AUC decreased in the center and the margins as well. TTP rose, however these changes did not reach the level of significance.

CONCLUSION

Analyzing the capillary microcirculation TICs offer a possibility of monitoring therapy-induced capillary changes of vascular malformations.

Reduced microperfusion due to portal vein thrombosis: Impact on the outcome of percutaneous thermal tumor ablation

PURPOSE

To determine the influence of pre-interventionally existing portal vein thrombosis on the ablation success of percutaneous tumor ablation of HCC.

MATERIALS AND METHODS

15 patients with HCC and pre-existing portal vein thrombosis underwent thermal tumor ablation. We retrospectively analyzed the pre- and post-interventionally performed CT and MRI scans in terms of technical success as well as the complication rate. The portal vein thrombosis was classified into segmental, lobar and central thrombus.

RESULTS

In 13/15 cases (87%) complete ablation with no evidence of residual tumor tissue was seen 6 weeks after the procedure in contrast-enhanced MRI scans and contrast-enhanced ultrasound (CEUS). No major and 2 minor complications were observed after the ablation procedure.

CONCLUSION

Reduced perfusion due to pre-interventionally existing portal vein thrombosis has no significant impact on the ablation success or the complication rate.

The EFSUMB Guidelines and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound (CEUS) in Non-Hepatic Applications: Update 2017 (Short Version)

The updated version of the EFSUMB guidelines on the application of non-hepatic contrast-enhanced ultrasound (CEUS) deals with the use of microbubble ultrasound contrast outside the liver in the many established and emerging applications.

The EFSUMB Guidelines and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound (CEUS) in Non-Hepatic Applications: Update 2017 (Long Version)

The updated version of the EFSUMB guidelines on the application of non-hepatic contrast-enhanced ultrasound (CEUS) deals with the use of microbubble ultrasound contrast outside the liver in the many established and emerging applications.

Analysis of arterial dynamic micro-vascularization with contrast-enhanced ultrasound (CEUS) in thyroid lesions using external perfusion software: First results

AIM

To determine different perfusion characteristics of histo-pathologically proven adenomas and carcinomas of the thyroid gland with CEUS and perfusion software.

MATERIAL AND METHODS

Retrospective perfusion analysis of 25 patients with carcinomas and 41 cases of adenomas of the thyroid gland (30 males, 36 females; aged 18 - 85 years, mean 56 years). All cases were histologically analyzed. Perfusion analysis was independently performed using external perfusion software (VueBox®). TTP, mTT, Peak and Rise time were calculated.

RESULTS

Lesions' sizes ranged from 0.2 to 10.2 cm in carcinomas (mean 2.18 cm), and from 0.6 to 5.0 cm in adenomas (mean 2.25 cm). In 20 out of 25 carcinomas that were evaluated with CEUS, a complete wash-out in the late venous phase was found. Adenomas showed wash-out at the border.Perfusion analysis in VueBox® revealed some parameters which tend to show differences between adenomas and carcinomas, however did not reach the level of significance.Median Peak in carcinomas was highest at the margins (2945 rU), and lowest in the surroundings (1110 rU). Mean Transit Time (mTT) values showed no differences between center, margin and surrounding.In adenomas healthy tissue showed higher mTT values compared to the center (24.6 vs. 20.7 sec). Median Peak was highest in the surrounding tissue and lowest in the margins (1999 vs. 1129 rU). No statistical differences could be found in the comparisons.

CONCLUSION

CEUS with perfusion analysis offers new possibilities for the dynamic evaluation of micro-vascularization in thyroid adenomas and carcinomas. Using VueBox® the perfusion analysis of the arterial phase provides new parameters that help determine a lesion's malignancy or benignity. However a final assessment regarding malignancy and benignity of thyroid lesions using only CEUS and perfusion analysis of the arterial phase is not yet possible.

Intrasurgical dignity assessment of hepatic tumors using semi-quantitative strain elastography and contrast-enhanced ultrasound for optimisation of liver tumor surgery

OBJECTIVE

To evaluate the efficacy of strain elastography (SE) using semi-quantitative measurement methods compared to constrast enhanced ultrasound during liver tumor surgery (Io-CEUS) for dignity assessment of focal liver lesions(FLL).

MATERIAL AND METHODS

Prospective data acquisition and retrospective analysis of US data of 100 patients (116 lesions) who underwent liver tumor surgery between 10/2010 and 03/2016. Retrospective reading of SE color patterns was performed establishing groups depending on dominant color (>50% blue = stiff, inhomogenous, >50% yellow/red/green = soft tissue). Semi-quantitative analysis was performed by Q-analysis based on a scale from 0 (soft) to 6 (stiff). 2 ROIs were placed centrally, 5 ROIs in the lesion's surrounding tissue. Io-CEUS was performed by bolus injection of 5-10 ml sulphurhexaflourid microbubbles evaluating wash-in- and -out- kinetics in arterial, portal venous and late phase. Histopathology after surgical resection served as goldstandard.

RESULTS

100 patients (m: 65, f: 35, mean age 60.5 years) with 116 liver lesions were included. Lesion's size ranged from 0.5 to 8.4 cm (mean 2.42 cm SD±1.44 cm). Postoperative histology showed 105 malignant and 11 benign lesions. Semi-quantitative analysis showed central indurations of >2.5 in 76/105 cases suggesting malignancy. 7 benign lesions displayed no central indurations correctly characterized benign by SE. ROC-analysis and Youden index showed a sensitivity of 72.4% and specificity of 63.6% assuming a cut-off of 2.5. Io-CEUS correctly characterized 103/105 as malignant. Sensitivity was 98%, specificity 72.7%.

CONCLUSION

Strain elastography is a valuable tool for non-invasive characterization of FLLs. Semi-quantitative intratumoral stiffness values of >2.5 suggested malignancy. However, sensitivity of Io-CEUS in detecting malignant lesions was higher compared to SE. In conclusion SE should be considered for routine use during intraoperative US in addition to Io-CEUS for optimization of curative liver surgery.

Effect of radiographic contrast media on renal perfusion - First results

BACKGROUND

Intra-arterial administration of radiographic contrast media (CM) is discussed to impair renal perfusion. The pathogenesis of contrast-induced Nephropathy (CIN) is still not clarified.

OBJECTIVE

This trial was performed to prove the effects of two CM with different molecular structure on renal perfusion.

METHODS

A prospective, randomized study on 16 pigs was designed to compare the outcome after application of a low-osmolar iodinated CM (770 mOsm/kg H2O - Group1) and an iso-osmolar iodinated CM (290 mOsm/kg H2o - Group2).Color Coded Doppler Sonography (LOGIQ E9, GE, Milwaukee, USA) was applied for measuring the Renal Resistive Index (RRI) before and after the first, fifth, and tenth bolus of CM. Statistics was performed using analysis of variance for repeated measurements with the Factor "CM".

RESULTS

All flow spectra were documented free of artifacts and Peak Systolic Velocity (PSV), Enddiastolic Velocity (EDV) and RRI respectively could be calculated. Mean PSV in Group 1 led to a decrease while in Group 2 PSV showed a significant increase after CM (p = 0,042). The course of the mean EDV in both groups deferred accordingly (p = 0,033). Mean RRI over time significantly deferred in both groups (p = 0,001). It showed a biphasic course in Group 2 and a decrease over time in Group 2.

CONCLUSION

While iso-osmolar CM induced an increase of PSV and EDV together with a decrease of RRI, low-osmolar CM could not show this effect or rather led to the opposite.

Macro- and microcirculation patterns of intrahepatic blood flow changes in patients with hereditary hemorrhagic telangiectasia

AIM

To evaluated vascular dynamic processes in the liver of hereditary hemorrhagic telangiectasia (HHT) patients by ultrasound (US) considering quantitative analytic methods.

METHODS

The imaging features on US and contrast-enhanced ultrasound (CEUS) in 18 patients diagnosed with HHT were retrospectively analyzed. Regarding CEUS, real-time contrast harmonic imaging and sulfur hexafluoride-filled microbubbles were used.

RESULTS

HVaMs were identified in all 18 patients. By US, the two major Caselitz criteria could be detected in 55.6% patients. "Color spots" were detected in 72.2% of the cases. Respecting sonographic grading criteria by Buscarini, grade 3 could be demonstrated most frequent (40%). By CEUS, all the patients showed quick and early hyperenhancement during the arterial phase. Significant lowest time to peak (TTP) and highest area under the curve (AUC) values were identified in the hepatic artery (TTP: 69.8%; AUC: 100%) and highest TTP and lowest AUC in the hepatic parenchyma and the portal vein.

CONCLUSION

For the first time we analyzed CEUS findings of a group of HHT patients regarding macro- and microcirculation. Our data demonstrate significant differences in TTP and AUC values in the four selected regions: hepatic artery, shunt region, portal vein and hepatic parenchyma.

[Possibilities of sonographic image fusion: Current developments]

CLINICAL/METHODICAL ISSUE

For diagnostic and interventional procedures ultrasound (US) image fusion can be used as a complementary imaging technique.

METHODICAL INNOVATIONS

Image fusion has the advantage of real time imaging and can be combined with other cross-sectional imaging techniques.

PERFORMANCE

With the introduction of US contrast agents sonography and image fusion have gained more importance in the detection and characterization of liver lesions.

ACHIEVEMENTS

Fusion of US images with computed tomography (CT) or magnetic resonance imaging (MRI) facilitates the diagnostics and postinterventional therapy control.

PRACTICAL RECOMMENDATIONS

In addition to the primary application of image fusion in the diagnosis and treatment of liver lesions, there are more useful indications for contrast-enhanced US (CEUS) in routine clinical diagnostic procedures, such as intraoperative US (IOUS), vascular imaging and diagnostics of other organs, such as the kidneys and prostate gland.

Living-donor parathyroid allotransplantation for therapy-refractory postsurgical persistent hypoparathyroidism in a nontransplant recipient - three year results: a case report

Background

Therapy-refractory persistent hypoparathyroidism after extensive neck surgery is a rare but severe complication. Parathyroid allotransplantation may represent a definitive treatment option.

Case presentation

A 32-year old female was referred to our hospital with intractable persistent hypocalcemia after neck surgery for papillary thyroid cancer. Despite optimal medical treatment including calcium and vitamin D supplementation and even hormonal replacement therapy hypocalcemic symptoms failed to improve. The quality of life was considered very low. In light of the unsuccessful medical therapy and the young age of the patient parathyroid allotransplantation seemed an attractive treatment option to restore normal calcium homeostasis despite of the need for immunosuppressive therapy after the procedure. Therefore, we performed living-donor allotransplantation of two healthy parathyroid glands to the recipient’s left forearm. The surgical intervention was successful. Neither the donor nor the recipient showed any complications. In the postoperative course clinical symptoms of hypocalcemia significantly improved whereas serum calcium and parathyroid hormone (PTH) levels progressively increased into the normal range. Former intense replacement therapy could be discontinued completely in a stepwise fashion. To date, nearly three years after transplantation, the patient remains asymptomatic with normal serum levels of calcium and PTH.

Conclusion

Successful living-donor parathyroid allotransplantation for postsurgical hypoparathyroidism represents an innovative therapeutic strategy that could provide the definitive treatment in those patients in which the disease is therapy-refractory. The procedure can be justified even in nontransplant recipients. Retrieval of parathyroid glands from healthy donors is feasible and safe.

Evaluation of the diagnostic accuracy of CEUS in children with benign and malignant liver lesions and portal vein anomalies

OBJECTIVE

Comparison of the diagnostic findings of MRI, CT and CEUS in children with benign and malignant and portal venous anomalies of the liver.

MATERIALS/METHODS

Retrospective analysis of the diagnostic findings of CEUS, MRI and CT scans in 56 children (age 0-17 years) with a total of 60 benign and malignant liver lesions and anomalies of the portal vein/perfusion. All patients underwent CEUS using sulphur hexafluoride microbubbles and a multi-frequency probe (1-5 MHz, 6-9 MHz). Cine-loops were stored up to 3 minutes. MRI was performed in 38 lesions. CT was performed in 8 lesions.

RESULTS

Out of the 56 patients 49 liver lesions (48 benign, 1 malignant), 9 anomalies of the portal vein/perfusion and 2 of the biliary system were detected. 16/49 lesions were analyzed histopathologically. Using CEUS, the characterization of the lesions was possible in 45 out of 49 cases. In 32 cases, CEUS provided the exact diagnosis. Only two benign lesions were falsely categorized as malignant.Findings of MRI and CEUS were concordant in 84% of cases (n = 32/38). CEUS considered 1 benign lesion to be malignant. 2 lesions were not detectable and in 3 lesions no definite diagnosis was established using MRI.Findings of CT and CEUS were concordant in 5 of 8 cases. In 21 lesions CEUS as the only imaging modality was found to be sufficient for diagnostics.

CONCLUSION

Despite the restricted indications for using CEUS in children, it offers a high diagnostic detection rate (93%) for characterization of liver lesions and portal vein anomalies.

Percutaneous irreversible electroporation (IRE) of prostate cancer: Contrast-enhanced ultrasound (CEUS) findings

PURPOSE

To evaluate the use of contrast-enhanced ultrasound (CEUS) after irreversible electroporation (IRE) of prostatic cancer tissue to assess the ablation status by depicting microvascularisation in the ablation area.

MATERIALS AND METHODS

Retrospective evaluation of CEUS of 13 patients (mean age: 61.4 ± 7.5 years) with histologically confirmed prostatic cancer who underwent percutaneous IRE. In the course of clinical routine, the tumor lesions were documented before, immediately after, and 1 day after the ablationusing color-coded transabdominal and transrectal CEUS. The obtained image data (DICOM loops and images) were subsequently evaluated by 2 experienced radiologists and assessed with regard to micro vascularisation by means of a 5-point scale.

RESULTS

CEUS images showed significantly reduced microcirculation of the lesions (mean 0.9 ± 0.6 cm (0.5-1.5 cm) after IRE. Microcirculation was reduced from 2.15 ± 0.56 prior to ablation to 0.65 ± 0.63 (p <  0.001) immediately after the ablation and to 0.27 ± 0.44 one day after IRE (p <  0.001).

CONCLUSION

This study showed rapid and significant reduction of the microcirculation in the ablation area afterpercutaneous IRE of prostatic cancer tissue.

High-Resolution Ultrasound Including Contrast-Enhanced Ultrasound (CEUS) for the Detection of Gas Formation during Aspergillus Fumigatus Infection in Mice

PURPOSE

A. fumigatus infections represent a major threat for patients with a suppressed immune system. Early diagnosis is of importance for a favorable outcome but appears to be difficult due to limited diagnostic procedures. Here we investigated the sensitivity of high-resolution ultrasound (HRU) for the detection of A. fumigatus infection in the liver.

MATERIALS AND METHODS

BALB/c mice were intravenously infected with A. fumigatus and monitored by HRU, Doppler sonography (CCDS), contrast-enhanced ultrasound (CEUS), and real-time strain color-coded elastography (CCE) using a multi-frequency probe (6 - 15 MHz). Contrast media bolus injection of sulfur-hexafluoride micro-bubbles was applied and digital cine-loops from the arterial phase, as well as the portal venous phase up to the late phase of the whole liver were analyzed. All data were correlated to the histopathological findings.

RESULTS

Using HRU and CEUS, a sonic shadow was detected in all infected animals. All Aspergillus-infected nodes from 3 - 6 mm in the liver showed a shadow with rim enhancement and no intranodal enhancement when using CEUS. A. fumigatus infection was confirmed by CFU assessment and histopathological analysis. Granulomas were not associated with shadowing on B-mode. In contrast, granulomas with a diameter above 5 mm and a higher stiffness in CCE generated particularly an arterial rim enhancement and portal venous washout without contrast media uptake in the late phase. In addition, CEUS was able to define dynamic capillary microvascularization of infected liver areas.

CONCLUSION

Liver lesions associated with A. fumigatus infection can be detected in mice when combined with CEUS and CCE in vivo.

Improved Detection of preclinical Colorectal Liver Metastases by High Resolution Ultrasound including Molecular Ultrasound Imaging using the targeted Contrast Agent BR55

PURPOSE

Aim of the present study was to investigate the sensitivity of high resolution ultrasound (HRU), standard contrast-enhanced ultrasound (CEUS) and CEUS using a novel vascular endothelial growth factor receptor 2 (VEGFR2)-targeted contrast agent for the detection of hepatic metastases in a mouse model of colorectal cancer using clinical standard technology.

MATERIALS AND METHODS

The human colon cancer cell line HT29, transfected with luciferase cDNA for in vivo bioluminescence monitoring, was injected intrasplenically into CB17.SCID mice. Mice were monitored weekly by bioluminescence and after 2 and 4.5 weeks by HRU and CEUS. Contrast media (untargeted BR1, targeted BR55) was applied and digital cine loops from the arterial phase (15 - 45 sec), portal venous phase (50 - 120 s) and late phases (3 - 5 min, 1hour) of the whole liver were analyzed. Data were correlated with postmortem histopathology.

RESULTS

Without contrast enhancement, lesions > 4 mm were reliably detected. After use of untargeted CEUS, lesions > 2 mm were reliably detected and enhanced rim vascularization and late-phase wash-out was shown. With BR55, lesions > 0.8 mm were reliably detected with excellent documentation of vascularization. A persistent contrast enhancement was seen > 30 min after injection. Contrast-enhancement patterns with BR55 significantly correlated with CD31 (R2 = 0.74) and VEGFR2-immunohistochemistry (R2 = 0.66).

CONCLUSION

Detection of metastases by HRU and CEUS was earlier and more accurate than monitoring via bioluminescence. In vivo monitoring of hepatic micrometastases can thus be performed without prior modification of cancer cells using standard technology.

Modern Ultrasound Diagnostic Procedures in an Interdisciplinary Ultrasound Department: Challenge and Opportunities for Radiologists

Interdisciplinary ultrasound departments are sources for modern and effective ultrasound diagnostic procedures. Radiologists have a very important role as part of these centers for the establishment of new diagnostic ultrasound modalities like contrast-enhanced ultrasound (CEUS), image fusion between US and computed tomography (CT) and magnetic resonance tomography (MRI), resulting in new interventional procedures. Data acquisition and the development of solutions for PACS are also important points.

Identification of early complications following pancreas and renal transplantation using contrast enhanced ultrasound (CEUS)--first results

AIM

Identification of acute and subacute complications following pancreas and renal transplantation using contrast enhanced ultrasound (CEUS) in comparison with Magnetic Resonance Tomography (MRI), Computed Tomography (CT), Digital Subtraction Angiography (DSA) or Ultrasound (US). The study evaluated whether CEUS could confirm the preliminary diagnosis or even provide additional information, relevant for the therapeutic strategy.

MATERIAL AND METHODS

Retrospective evaluation of 19 patients (13 male, 6 female, age 26-77 years, mean 53.2 years) following renal transplantation and 10 patients (4 male, 6 female, age 35-56 years, mean 45.7 years) following combined pancreas and renal transplantation. CEUS was used as an additional diagnostic method when obscure diagnostic findings occurred in US, CT, MRI or DSA. Fundamental B-scan, Color Coded Doppler Sonography (CCDS) and CEUS were performed in all patients by an experienced examiner using a multifrequency convex transducer (1-5 MHz). After a bolus injection of up to 2.4 ml SonoVue® [BRACCO, Italy] digital raw data was stored as cine-loops up to 5 minutes in length.

RESULTS

In all patients, the pathological features and suspected diagnostic findings identified in the other imaging modalities could be confirmed using CEUS (100%). In 25 out of 29 patients (86.2%), new clinically relevant findings were detected. In 27 patients, the diagnosis of CEUS was confirmed during surgery (7), DSA (5), follow-up CEUS (13), CT (1) and MRI (1). In 4 patients renal AV-fistulas were found following biopsy, 3 patients showed post-operative allograft arterial stenosis or dissection, 1 patient demonstrated a stenosis of the common iliac artery and 2 patients were diagnosed with post-operative allograft venous thrombosis or stenosis. In 2 patients, a definite diagnosis of a benign lesion following renal transplantation was possible. In 1 patient a malignant lesion was suspected and confirmed following surgery. In 6 patients, normal perfusion of the pancreas and renal parenchyma and the corresponding vessels was diagnosed, in 5 patients the parenchymal perfusion was diminished and 1 patient suffered from pancreatitis.

CONCLUSION

These first results show that CEUS can provide additional, clinically relevant informations in patients with acute and subacute complications following pancreas and renal transplantation. Thus, an early application within the diagnostic course seems favorable.

Evaluating post-interventional occlusion grades of cerebral aneurysms with transcranial contrast-enhanced ultrasound (CEUS) using a matrix probe

PURPOSE

The main goal of cerebral endovascular aneurysm therapy is the complete occlusion of the aneurysm. Along with the development of new aneurysm treatment devices, repeated controls are necessary. We examined whether contrast-enhanced ultrasound can help to monitor aneurysms after endovascular treatment.

MATERIALS AND METHODS

We prospectively examined 12 patients after coiling (7 patients) or flow diverter (FD) implantation (5 patients). These patients were examined with transcranial contrast-enhanced ultrasound using a matrix probe (1 - 5 MHz). Doppler sonography, Power Doppler, contrast harmonic imaging (CHI) and Power Doppler sonography (CPD) were included in the examination. Digital subtraction angiography with 3 D reconstructions served as the gold standard. Two radiologists decided in consensus about the degree of aneurysm occlusion separately in CEUS and digital subtraction angiography using a 4-point grading scheme.

RESULTS

The degree of occlusion of the 12 aneurysms comparing the two imaging modalities was identical in 10 cases. In two cases CHI and CPD showed a small aneurysm remnant after coiling in the center of the coil pack while in digital subtraction angiography the aneurysms seemed completely occluded.

CONCLUSION

The investigation indicates that contrast-enhanced ultrasound is a supportive, noninvasive method for post-interventional controls of intracranial aneurysms due to its ability to display not only macro- but also microvascularization.

New economic training model for installing ultrasound-guided drainages

Abscesses and circumscribed collections of fluid are frequently found as complications of infectious diseases or surgery. Drainage is often indicated. We have established a new, economic, easy-to-make model to learn and improve competence in installing ultrasound-guided drainage. Up to fifteen water balloons (size 30 - 50 mm) were placed in a plastic box which then was filled with instant custard powder mixed with water. Spiral computed tomography (CT) of this box was performed. Experienced (n = 8) and inexperienced examiners (n = 8) drained the balloons via a direct puncture technique using either ultrasound-guidance alone or volume navigation with image fusion (ultrasound and CT) with needle tracking. Trainees filled out a questionnaire (before and after training) asking for information on their experience in ultrasound, in installing drainages and evaluating the new model. The time needed for installing the drainage was measured. None of the participants had ever attended a course on drainage installation. Only a few of the experienced examiners (n = 3) would autonomously install a drainage into a fluid collection with a size exceeding 4 cm before training. After training all participants felt more confident in ultrasound and in installing drainages into abscesses or other fluid collections. Most of the participants rated additional volume navigation with image fusion as a helpful tool. Ultrasound-guided drainage of abscesses can be trained easily with this new and economic model. Students and physicians can improve their skills and gain confidence in performing ultrasound-guided interventions.