Evaluation of Doppler-ultrasonography in the diagnosis of transjugular intrahepatic portosystemic shunt dysfunction: A prospective study

Quantitative analysis of in-TIPS thrombosis in abdominal CT

Purpose

To identify transjugular intrahepatic portosystemic shunt (TIPS) thrombosis in abdominal CT scans applying quantitative image analysis.

Materials and methods

We retrospectively screened 184 patients to include 20 patients (male, 8; female, 12; mean age, 60.7 ± 8.87 years) with (case, n = 10) and without (control, n = 10) in-TIPS thrombosis who underwent clinically indicated contrast-enhanced and unenhanced abdominal CT followed by conventional TIPS-angiography between 08/2014 and 06/2020. First, images were scored visually. Second, region of interest (ROI) based quantitative measurements of CT attenuation were performed in the inferior vena cava (IVC), portal vein and in four TIPS locations. Minimum, maximum and average Hounsfield unit (HU) values were used as absolute and relative quantitative features. We analyzed the features with univariate testing.

Results

Subjective scores identified in-TIPS thrombosis in contrast-enhanced scans with an accuracy of 0.667 – 0.833. Patients with in-TIPS thrombosis had significantly lower average (p < 0.001), minimum (p < 0.001) and maximum HU (p = 0.043) in contrast-enhanced images. The in-TIPS / IVC ratio in contrast-enhanced images was significantly lower in patients with in-TIPS thrombosis (p < 0.001). No significant differences were found for unenhanced images. Analyzing the visually most suspicious ROI with consecutive calculation of its ratio to the IVC, all patients with a ratio < 1 suffered from in-TIPS thrombosis (p < 0.001, sensitivity and specificity = 100%).

Conclusion

Quantitative analysis of abdominal CT scans facilitates the stratification of in-TIPS thrombosis. In contrast-enhanced scans, an in-TIPS / IVC ratio < 1 could non-invasively stratify all patients with in-TIPS thrombosis.

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Quantitative image analyses of CT scans allow the diagnosis of in-TIPS thrombosis.

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Negative quantitative image analysis may reduce the necessity of an angiography.

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Unenhanced CT scans have no additional benefit for diagnosis of in-TIPS thrombosis.

Diagnostic Value of Contrast-Enhanced Ultrasound for Evaluation of Transjugular Intrahepatic Portosystemic Shunt Perfusion

BACKGROUND

In patients with liver cirrhosis, transjugular intrahepatic portosystemic shunt (TIPS) displays an effective method for treating portal hypertension. Main indications include refractory ascites and secondary prevention of esophageal bleeding. Color Doppler ultrasound (CDUS) plays a leading role in the follow-up management, whereas contrast-enhanced ultrasound (CEUS) is not routinely considered. We compared the efficacy of CEUS to CDUS and highlighted differences compared to findings of corresponding computed tomography (CT) and magnetic resonance imaging (MRI). (2) Methods: On a retrospective basis, 106 patients with CEUS examination after TIPS were included. The enrollment period was 12 years (between 2008 and 2020) and the age group ranged from 23.3 to 82.1 years. In addition, 92 CDUS, 43 CT and 58 MRI scans were evaluated for intermodal comparison. (3) Results: Intermodal analysis and comparison revealed a high level of concordance between CDUS, CT and MRI in the vast majority of cases. In comparison to CDUS, the correlation of the relevant findings was 92.5%, 95.3% for CT and 87.9% for MRI. In some cases, however, additional information was provided by CEUS (4) Conclusions: CEUS depicts a safe and effective imaging modality for follow-up after TIPS. In addition to CDUS, CEUS enables specific assessment of stent pathologies and stent dysfunction due to its capacity to dynamically visualize single microbubbles at high spatial and temporal resolution. Due to the low number of adverse events regarding the application of contrast agents, CEUS can be administered to a very broad patient population, thus avoiding additional radiation exposure compared to CT angiography in cases with divergent findings during follow-up.

Role of Doppler Ultrasound Combined With Clinical Features in the Diagnosis of Transjugular Intrahepatic Portosystemic Shunt Dysfunction in the Era of Covered Stents

OBJECTIVES

Our goal was to discuss the role of Doppler ultrasound (US), combined with clinical features, in the diagnosis of transjugular intrahepatic portosystemic shunt (TIPS) dysfunction in the era of covered stents. In light of the lack of research regarding the accuracy of Doppler US in TIPS dysfunction evaluations when using covered stents and a recent major meta-analysis, which primarily reviewed studies with bare metal stents but few with covered stents, we aimed to provide our single-center case study for further investigation.

METHODS

All patients from 2010 to 2019 who underwent angiography for a covered stent preceded by a Doppler US examination in our institution were retrospectively reviewed.

RESULTS

All of the Doppler US and angiographic examination results showed complete agreement, and 11 of 12 were positive for TIPS dysfunction.

CONCLUSIONS

Combining the presence of positive clinical signs for TIPS dysfunction with Doppler US may increase its accuracy. Considering our results, there may be a need to reinvestigate Doppler US as a noninvasive, inexpensive, and available tool for the diagnosis of TIPS dysfunction in the era of covered stents, despite recent publications depicting Doppler US as inadequate for evaluating a TIPS.

Performance of ultrasound for detection of transjugular intrahepatic portosystemic shunt dysfunction: a meta-analysis

PURPOSE

Although ultrasound has been widely used to evaluate transjugular intrahepatic portosystemic shunts (TIPS) patency, several studies have reported conflicting data regarding its performance. Therefore, we aimed to evaluate performance of ultrasound for detection of TIPS dysfunction by performing a meta-analysis.

METHODS

Literature search was performed for studies evaluating ultrasound for TIPS dysfunction, stenosis, and occlusion using PubMed, EMBASE, Scopus, and Cochrane Library through February 2019. Pooled sensitivity, specificity, log diagnostic odds ratio (LDOR), and area under curve (AUC) of summary receiver-operating characteristic were calculated. Subgroup analyses were performed according to ultrasonographic criteria and type of stent.

RESULTS

In total, 21 studies were evaluated. Pooled sensitivity, specificity, and LDOR of ultrasound for detection of TIPS dysfunction were 0.82 (0.67, 0.93), 0.58 (0.46, 0.70), and 1.77 (1.20, 2.35). Pooled sensitivity, specificity, and LDOR for TIPS stenosis were 0.80 (0.69, 0.90), 0.80 (0.69, 0.91), and 2.83 (1.88, 3.78). Pooled sensitivity, specificity, and LDOR for TIPS occlusion were 0.96 (0.92, 0.99), 1 (0.99, 1.00), and 6.28 (4.96, 7.60). AUCs of ultrasound for TIPS dysfunction, stenosis, and occlusion were 0.77, 0.86, and 0.95, respectively.

CONCLUSIONS

Although ultrasound had excellent performance for TIPS occlusion and acceptable performance for TIP stenosis, most studies utilized bare metal stent, and therefore, application to current practice is limited. Ultrasound for TIPS dysfunction in the setting of covered metal stent appeared to have acceptable sensitivity of 0.82, but limited specificity of 0.58 and low LDOR of 1.77. A new noninvasive tool is needed for detection of TIPS dysfunction in the era of covered metal stent.