Duplex sonography of the mesenteric vessels--a critical evaluation of inter-observer variability

The Doppler Perfusion Index of the Liver and the Underlying Duplex Sonography of Visceral Vessels-A Systematic and Comprehensive Evaluation of Reproducibility

Prior to the curative resection of colorectal carcinoma (CRC) or pancreatic ductal adenocarcinoma (PDAC), the exclusion of hepatic metastasis using cross-sectional imaging is mandatory. The Doppler perfusion index (DPI) of the liver is a promising method for detecting occult liver metastases, but the underlying visceral duplex sonography is critically viewed in terms of its reproducibility. The aim of this study was to investigate systematically the reproducibility of the measured variables, the calculated blood flow, and the DPI. Between February and September 2023, two examinations were performed on 80 subjects within a period of 0-30 days and at two previously defined quality levels, aligned to the German standards of the DEGUM. Correlation analyses were carried out using Pearson's correlation coefficient (PCC) and the intraclass correlation coefficient (ICC). The diameters, blood flow, and DPI showed a high degree of agreement (PCC of 0.9 and ICC of 0.9 for AHP). Provided that a precise standard of procedure is adhered to, the Doppler examination of AHC, AHP, and PV yields very reproducible blood flows and DPI, which is a prerequisite for a comprehensive investigation of its prognostic value for the prediction of metachronous hepatic metastasis in the context of curatively treated CRC or PDAC.

The diagnostic value of Doppler Resistive Index in the differential diagnosis of focal liver lesions

Aim

To investigate the diagnostic value of resistance index (RI) in differentiating focal liver lesions.

Patients and methods

In this retrospective study, a total of 576 patients with histologically confirmed focal liver lesions were included. Each patient underwent B-mode ultrasound examination and color Doppler ultrasound examination. The RI values of different focal liver lesions were recorded and compared.

Results

The mean RI value of benign lesions was significantly lower than that of malignant lesions (0.54 ± 0.10 vs. 0.71 ± 0.12) (p <0.05). In malignant lesions, the RI value of intrahepatic cholangiocarcinoma was significantly lower than that of hepatocellular carcinoma lesions. Furthermore, in hepatocellular carcinoma lesions, the RI of large lesions (group 4: >10 cm) was significantly lower than that of small lesions (group 1: ≤2 cm, group 2: 2-5 cm) (p <0.05). Taken RI of 0.615 as a cutoff value to differentiate malignant and benign lesions, the sensitivity, specificity, positive predictive value and negative predictive value were 82.80%, 81.00%, 81.34% and 82.48%, respectively.

Conclusion

Color Doppler ultrasound examination is a valuable imaging method in detecting blood flow signal within liver lesions. The RI parameter should be helpful in differentiating malignant and benign liver tumors.

Ultrasound evaluation of bowel vasculopathy in systemic sclerosis

BACKGROUND

Gastrointestinal (GI) manifestations are frequent in systemic sclerosis (SSc) with an impact on quality of life and morbidity. Bowel vasculopathy is a key pathogenetic factor responsible for GI involvement.

OBJECTIVES

To compare abdominal ultrasound (US) and Color Doppler Ultrasonography (CDU) features of splanchnic vessels of SSc patients with healthy controls.

METHODS

The charts of SSc patients who underwent an abdominal US and CDU study were retrospectively analyzed. For Superior Mesenteric Artery (SMA) and Inferior Mesenteric Artery (IMA) caliber, Peak Systolic Velocity (PSV), Reverse Velocity (RV), End-Diastolic Velocity (EDV), Mean Velocity (mV), Blood-flow, Resistive Index (RI) and Pulsatility Index (PI) were recorded.

RESULTS

28 SSc patients and 28 controls were enrolled. In SSc, caliber of SMA was significantly smaller than in controls (5.75 ± 0.62 mm vs. 6.45 ± 0.60 mm, p < 0.0001 - p adj =0.0002). The flow study of SMA and IMA showed a significant reduction of RV (SMA: 7.25 ± 6.37 cm/s vs. 18.52 ± 6.16 cm/s, p < 0.0001 - p adj <0.0001; IMA: 2.69 ± 6.10 cm/s vs. 17.06 ± 5.75 cm/s, p < 0.0001 - p adj <0.0001) and PI (SMA: 3.33 ± 0.75 vs. 4.53 ± 1.03, p < 0.0001 - p adj =0.0002; IMA: 3.54 ± 0.95 vs. 6.08 ± 1.53, p < 0.0001 - p adj <0.0001) in SSc patients than controls.

CONCLUSION

involvement of splanchnic vessels in SSc may be non-invasively investigated with abdominal US and CDU. Morphological and functional changes of Doppler parameters observed in SMA and IMA clearly demonstrate that these vessels are affected by SSc vasculopathy.

Imaging features of hepatic sinusoidal obstruction syndrome or veno-occlusive disease in children

Hepatic sinusoidal obstruction syndrome, also known as veno-occlusive disease, can occur as a complication of myeloablative chemotherapy, as a result of low-intensity chemotherapy-related liver toxicity or radiotherapy of the liver. Symptoms of sinusoidal obstruction syndrome can range from asymptomatic to liver dysfunction or severe disease with life-threatening acute multi-organ failure. Imaging features can suggest or support this clinical diagnosis. Familiarity with the imaging spectrum of sinusoidal obstruction syndrome is therefore important for both radiologists and clinical oncologists. Here, multi-modality radiologic appearances of sinusoidal obstruction syndrome in pediatric patients are illustrated, including outcome after follow-up.

Reliability of an ultrasonographical scoring system for diagnosis of sinusoidal obstruction syndrome/veno-occlusive disease in patients with hematopoietic stem cell transplantation

PURPOSE

Sinusoidal obstruction syndrome (SOS)/hepatic veno-occlusive disease (VOD) is a fatal complication after hematopoietic stem cell transplantation. We previously reported the usefulness of an ultrasonographical (US) scoring system, the Hokkaido US-based scoring system consisting of ten parameters (HokUS-10): (1) hepatomegaly in the left lobe and (2) right lobe, (3) dilatation of the main portal vein (PV), (4) hepatofugal flow in the main PV, (5) decreased velocity of the PV, (6) dilatation of the para-umbilical vein (PUV), (7) appearance of blood flow signal in the PUV, (8) gallbladder (GB) wall thickening, (9) ascites, and (10) increased resistive index of the hepatic artery, for the diagnosis of SOS/VOD. However, the reliability of this system among operators remains elusive. Therefore, we prospectively evaluated the reliability of HokUS-10.

METHODS

Twenty-four healthy volunteers and 40 patients with liver dysfunction were enrolled. Inter- and intra-operator reliabilities were analyzed using three sonographers.

RESULTS

The median concordance rate of HokUS-10 among three sonographers and intra-operator in 24 volunteers was 92% (95% CI: 73-98%) and 98% (95% CI: 92-100%), respectively. In all 64 cases, in terms of the reliability between two sonographers for three representative US parameters (amount of ascites, GB wall thickening, and appearance of PUV blood flow signal), the median concordance rate was more than 98% (95% CI: 86-106%).

CONCLUSION

The inter- and intra-reliabilities of HokUS-10 were excellent. Thus, US might be a reliable tool for SOS/VOD diagnosis.

Gastrointestinal Ultrasound (GIUS) in Intestinal Emergencies - An EFSUMB Position Paper

An interdisciplinary group of European experts summarizes the value of gastrointestinal ultrasound (GIUS) in the management of three time-critical causes of acute abdomen: bowel obstruction, gastrointestinal perforation and acute ischemic bowel disease. Based on an extensive literature review, statements for a targeted diagnostic strategy in these intestinal emergencies are presented. GIUS is best established in case of small bowel obstruction. Metanalyses and prospective studies showed a sensitivity and specificity comparable to that of computed tomography (CT) and superior to plain X-ray. GIUS may save time and radiation exposure and has the advantage of displaying bowel function directly. Gastrointestinal perforation is more challenging for less experienced investigators. Although GIUS in experienced hands has a relatively high sensitivity to establish a correct diagnosis, CT is the most sensitive method in this situation. The spectrum of intestinal ischemia ranges from self-limited ischemic colitis to fatal intestinal infarction. In acute arterial mesenteric ischemia, GIUS may provide information, but prompt CT angiography is the gold standard. On the other end of the spectrum, ischemic colitis shows typical ultrasound features that allow correct diagnosis. GIUS here has a diagnostic performance similar to CT and helps to differentiate mild from severe ischemic colitis.

New Ultrasound Techniques Challenge the Diagnosis of Sinusoidal Obstruction Syndrome

Sinusoidal obstruction syndrome, also known as veno-occlusive disease (SOS/VOD), is a potentially life-threatening complication that can develop after hematopoietic cell transplantation. Clinically, SOS/VOD is characterized by hepatomegaly, right upper quadrant pain, jaundice and ascites, most often occurring within the first 3 wk after hematopoietic cell transplantation. Early therapeutic intervention is pivotal for survival in SOS/VOD. Thus, a rapid and reliable diagnosis has to be made. Diagnosis of SOS/VOD is based on clinical criteria, such as the Seattle, Baltimore or recently issued European Society for Blood and Marrow Transplantation criteria, to which hemodynamic and/or ultrasound evidence of SOS were added for the first time. However, to rule out major differential diagnoses and to verify the diagnosis, a reliable imaging method is needed. Ultrasound techniques have been proposed in SOS/VOD. Nevertheless, the sensitivity and specificity of transabdominal ultrasound and Doppler techniques need to be improved. Innovative ultrasound methods such as a combination of Doppler ultrasound with shear wave elastography and contrast-enhanced ultrasound techniques should be evaluated for diagnosis and follow-up of SOS/VOD. The goals of this review are to discuss currently available ultrasound techniques and to identify areas for future studies in SOS/VOD.

Discriminating chronic pancreatitis from pancreatic cancer: Contrast-enhanced EUS and multidetector computed tomography in direct comparison

BACKGROUND AND OBJECTIVES

To compare the ability of multidetector computed tomography (MDCT) and contrast-enhanced EUS to discriminate chronic pancreatitis (CP) from pancreatic ductal adenocarcinoma (PDAC).

SUBJECTS AND METHODS

A total of 215 patients (age: 62 ± 15 years, sex: f/m 80/135) were included in this retrospective study. All patients were examined by conventional endoscopic B-mode and contrast-enhanced high mechanical index EUS (CEHMI-EUS). CELMI-EUS was performed in 159 patients and endoscopic sonoelastography (ESE) in 210 patients. MDCT was carried out in 131 patients as part of their clinical work-up. Radiological reports were retrospectively analyzed. Final diagnosis was achieved by biopsy and evaluation of cytological specimens collected was performed by EUS-FNA, surgery, or follow-up of 12 months or more in patients with benign findings. In a subgroup of 100 patients, all diagnostic five methods were performed, and head-to-head analysis was performed.

RESULTS

Sensitivity and specificity for MDCT were 89% and 70% and for CEHMI-EUS were 96% and 91%, respectively. Sensitivities and specificities for EUS were 92% and 63% for B-Mode EUS, 96% and 38% for ESE, and 82% and 76% for CELMI-EUS, respectively. In the head-to-head analysis, each modality had shown lower numbers for specificity than shown in the overall group analysis because of high drop-out rate. EUS-FNA for PDAC had a sensitivity of 96% and a specificity of 100%.

CONCLUSIONS

Contrast-enhanced EUS is a reliable tool in discriminating PDAC from CP.

Is there evidence for more than two diffusion components in abdominal organs? - A magnetic resonance imaging study in healthy volunteers

The most commonly applied model for the description of diffusion-weighted imaging (DWI) data in perfused organs is bicompartmental intravoxel incoherent motion (IVIM) analysis. In this study, we assessed the ground truth of underlying diffusion components in healthy abdominal organs using an extensive DWI protocol and subsequent computation of apparent diffusion coefficient 'spectra', similar to the computation of previously described T₂ relaxation spectra. Diffusion datasets of eight healthy subjects were acquired in a 3-T magnetic resonance scanner using 68 different b values during free breathing (equidistantly placed in the range 0-1005 s/mm² ). Signal intensity curves as a function of the b value were analyzed in liver, spleen and kidneys using non-negative least-squares fitting to a distribution of decaying exponential functions with minimum amplitude energy regularization. In all assessed organs, the typical slow- and fast-diffusing components of the IVIM model were detected [liver: true diffusion D = (1.26 ± 0.01) × 10^-3 mm² /s, pseudodiffusion D* = (270 ± 44) × 10^-3 mm² /s; kidney cortex: D = (2.26 ± 0.07) × 10^-3 mm² /s, D* = (264 ± 78) × 10^-3 mm² /s; kidney medulla: D = (1.57 ± 0.28) × 10^-3 mm² /s, D* = (168 ± 18) × 10^-3 mm² /s; spleen: D = (0.91 ± 0.01) × 10^-3 mm² /s, D* = (69.8 ± 0.50) × 10^-3 mm² /s]. However, in the liver and kidney, a third component between D and D* was found [liver: D' = (43.8 ± 5.9) × 10^-3 mm² /s; kidney cortex: D' = (23.8 ± 11.5) × 10^-3 mm² /s; kidney medulla: D' = (5.23 ± 0.93) × 10^-3 mm² /s], whereas no third component was detected in the spleen. Fitting with a diffusion kurtosis model did not lead to a better fit of the resulting curves to the acquired data compared with apparent diffusion coefficient spectrum analysis. For a most accurate description of diffusion properties in the liver and the kidneys, a more sophisticated model seems to be required including three diffusion components.

How to perform gastrointestinal ultrasound: Anatomy and normal findings

Gastrointestinal ultrasound is a practical, safe, cheap and reproducible diagnostic tool in inflammatory bowel disease gaining global prominence amongst clinicians. Understanding the embryological processes of the intestinal tract assists in the interpretation of abnormal sonographic findings. In general terms, the examination principally comprises interrogation of the colon, mesentery and small intestine using both low-frequency and high-frequency probes. Interpretation of findings on GIUS includes assessment of bowel wall thickness, symmetry of this thickness, evidence of transmural changes, assessment of vascularity using Doppler imaging and assessment of other specific features including lymph nodes, mesentery and luminal motility. In addition to B-mode imaging, transperineal ultrasonography, elastography and contrast-enhanced ultrasonography are useful adjuncts. This supplement expands upon these features in more depth.