Comparison of Two High-End Ultrasound Systems for Contrast-Enhanced Ultrasound Quantification of Mural Microvascularity in Crohn's Disease

PURPOSE

To verify the reproducibility of contrast-enhanced ultrasound (CEUS) quantification results of two different high-end ultrasound systems and to evaluate the clinical utility of the method in patients with Crohn's disease (CD).

MATERIALS AND METHODS

18 patients with histologically confirmed CD (36.8 % women, 63.2 % men; mean age 43.7 ± 14.1 years) and wall segments thicker than 5 mm were recruited. CEUS quantification and conventional ultrasound investigation were performed under standardized settings using Toshiba Aplio500 and Siemens Acuson S3000 high-end ultrasound systems. CEUS was performed at a low mechanical index of 0.1 after bolus application of 4.8 ml of SonoVue(®) contrast medium. The recorded DICOM clips were quantified using VueBox(®) (version 4.3) calculating 11 quantitative parameters. Subsequently, CEUS quantification and conventional ultrasound results were analyzed.

RESULTS

Correlation of quantitative parameters between the Aplio500 and AcusonS3000 systems for peak enhancement (PE), rise time (RT), wash-in-rate (WiR) and quality of fit (QOF) yielded significance levels of p < 0.05 and p < 0.0001 for wash-in-wash-out area under the curve (WiWoAUC). Spearman rank test showed moderate levels of correlation for PE, RT, WiR and QOF (r = 0.5, 0.49, 0.49 and 0.5 respectively), and high correlation for WiWoAUC (r = 0.89) between the two ultrasound systems.

CONCLUSION

Due to multiple uncontrollable affecting factors, the method of CEUS quantification by VueBox in the intestine cannot be recommended for device-independent multicenter studies. Therefore we suggest to use identical ultrasound systems and probes as well as to establish adequate reference ROIS, like a AIF-ROI.

Influence of plasma cortisol and other laboratory parameters on nonalcoholic Fatty liver disease

The objective of the present study was to analyse the association between the plasma cortisol concentration and nonalcoholic fatty liver disease (NAFLD). A total of 1 326 subjects (age 18-65 years) were examined in the context of an epidemiological study of a population-based random sample. Medical history and anthropometric data of 662 women and 664 men were documented. In addition, laboratory examinations were performed and the fat concentration of the liver was estimated by ultrasound examination. Mean cortisol concentration in plasma was 260.4±156.8 nmol/l for women and 295.8±161.2 nmol/l for men. NAFLD was identified in 17.7% in women and 35.1% in men. Plasma cortisol concentration showed no association with the existence of NAFLD. NAFLD correlated positive with age, body-mass index (BMI), waist-to-hip-ratio (WHR), alanine aminotransferase (ALT), and triglycerides. The present study failed to establish any association of plasma cortisol concentrations and NAFLD.

Determination of vitality of liver lesions by alveolar echinococcosis

Objective of our study is qualitative and quantitative comparison of contrast enhanced ultrasound (CEUS) and 18F-FDG PETCT in monitoring hepatic alveolar echinococcosis (HAE). Parasitic liver lesions were examined regarding number, size, morphology, vascularization and metabolic activity. Patients, methods: 36 patients with medicallytreated HAE were included in this prospective clinical study. Abdominal ultrasound and CEUS were carried out using ultrasound contrast amplifier SonoVue®. As part of monitoring, patients were examined by 18F-FDG-PET-CT. Quantitative analysis of CEUS was performed using the Software Vue- Box™ Quantification Toolbox. Maximum contrast enhancement in lesions peak enhancement (PE) was used as parameter. For quantification of 18F-FDG PET-CT, maximum Standardized Uptake Value (SUVmax) of lesions was specified and statistically compared with PE. Results: 18F-FDG uptake in parasitic liver lesions was diagnosed by 18F-FDG PET-CT in 32 of 36 patients. Vascularization of liver lesions was detected by CEUS in 22 of 32 FDG-positive patients with sensitivity of 69% and specificity of 100%. Mean maximum diameter of lesions was 69.5mm in CEUS and 63.7mm in B-scan ultrasound (p < 0.0001). No significant correlation was found between SUVmax and PE (p = 0.8879). Conclusion: In comparison to FDG PET-CT, the gold standard for detecting viable lesions by depicting metabolism, CEUS detects viable lesions with high specificity and moderate sensitivity by showing vascularization. CEUS must be regarded as an important tool in monitoring HAE. Dimensions of parasitic lesions are displayed more precisely through CEUS than in B-scan. With currently available methods, CEUS quantification has no benefit in monitoring HAE lesions in daily clinical practice.

Associations of fatty liver disease and other factors affecting serum SHBG concentrations: a population based study on 1657 subjects

Sex hormone binding globulin (SHBG) is a glycoprotein expressed predominantly in the hepatocytes. It regulates the transport of sex steroid hormones in the blood stream to their target tissues. The expression of the SHBG gene is subject to multifactorial regulation including hormonal, metabolic, and nutritional aspects. Against this background, we investigated the effect of fatty liver and metabolic syndrome, together with other parameters, on serum SHBG concentrations in a population-based cohort in Germany. This cross-sectional study included 870 women and 787 men (average age 42.3±12.8 years), who underwent ultrasound screening for fatty liver in addition to providing a complete medical history and undergoing physical and laboratory examination. Fatty liver was diagnosed on ultrasound criteria in 159 women (18.3%) and 287 men (36.5%). Fatty liver was shown to exert a significant influence on serum SHBG concentrations in men and in premenopausal women. Men with grade 1 fatty liver had a 1.96-fold increased risk (95%-confidence interval=1.28-3.02; p=0.0022) and postmenopausal women with grade 1 fatty liver a 2.4-fold risk (95%-confidence interval=1.11-5.27; p=0.0267) for low SHBG concentrations. Among metabolic parameters, HDL-C represented as affecting factor in men (p=0.0058) and premenopausal women (p=0.0002), while cholesterol only showed an association in premenopausal women (p=0.0439) and triglyceride in postmenopausal women (p=0.0436). No association of concentrations of SHBG and metabolic syndrome was observed. Age, BMI and waist-to-hip ratio also influence the SHBG concentration. Based on these findings, we conclude that fat accumulation in the liver influences SHBG concentrations in men and premenopausal women.

A single dose of intravenous zoledronate prevents glucocorticoid therapy-associated bone loss in acute flare of Crohn's disease, a randomized controlled trial

OBJECTIVES

To assess the effectiveness and safety of zoledronate (ZOL) in preventing glucocorticoid therapy-associated bone loss in patients with acute flare of Crohn's disease (CD) in a randomized, double-blind, placebo-controlled trial.

METHODS

Forty CD patients starting a glucocorticoid therapy (60 mg prednisolone per day) for acute flare (CD activity index (CDAI) >220) were randomized to compare the effect of ZOL (4 mg intravenous, n=20) or placebo (n=20) on change in lumbar bone mineral density (BMD). All patients received calcium citrate (800 mg) and colecalciferol (1,000 IU) daily. Dual energy X-ray absorptiometry (DXA) of the lumbar spine (L1-L4) was performed at baseline and day 90. Follow-up examinations at day 1/7/14/30 and 90 included laboratory tests and adverse event/serious adverse events reports.

RESULTS

Thirty-six patients were available for per-protocol analysis. With placebo (n=18), a decrease in BMD was seen (T-score: -0.98 ± 0.8, day 0 and -1.25 ± 0.77, day 90, P=0.06), with ZOL (n=18) BMD increased (-1.15 ± 1.02, day 0 and -0.74 ± 1.09, day 90, P=0.03). The change in BMD under placebo (-0.26 ± 0.21) vs. ZOL (+0.41 ± 0.19) was highly significant (P=0.006). In all, 14 out of 18 patients with ZOL had an increase in BMD (+0.64 ± 0.48), 12 of 18 with placebo a decrease (-0.50 ± 0.39). Changes of clinical findings and laboratory results of inflammation (leukocytes, platelets, and C-reactive protein) were the same in- and between-groups throughout the study. With ZOL, serum bone degradation marker β-Cross-Laps decreased. Study medication was safe and well tolerated.

CONCLUSIONS

ZOL is effective in preventing glucocorticoid therapy-induced bone loss in patients with acute flare of CD and should be considered whenever a glucocorticoid therapy is started in CD patients.

[Gallbladder polyps: prevalence and risk factors]

PURPOSE

The objective of the present study was to investigate the prevalence of gallbladder polyps and possible risk factors in a random population sample of an urban population.

MATERIAL AND METHODS

A total of 2099 subjects (1072 women, 1027 men; aged 19 - 65 years, mean age 42.1 (SD ± 12.8 years) were prospectively examined using ultrasound, a standardized questionnaire and laboratory studies.

RESULTS

Gallbladder polyps were identified in 6.1 % (128 / 2099) of all subjects (women: 6.1 % [63 / 1027]); men: 6.1 % [65 / 1072]). Solitary polyps were found in 52.4 % (65 / 124), two polyps in 16.1 % (20 / 124), three polyps in 6.5 % (8 / 124), several polyps in 22.6 % (28 / 124) and multiple polyps in 2.4 % (3 / 124) of subjects. The mean polyp diameter was 4.7 mm (SD ± 2.2; range 2 - 20 mm). The polyp diameter was ≤ 7 mm in 94.5 % of subjects. The polyps were described as pedunculate in 82.3 % (102 / 124). The polyps were broad-based in 11.3 % of subjects (14 / 124; men: 18 % women: 4.8 %). The polyps were homogeneously echogenic in 100 % of cases and with irregular contours in only one male subject. Multiple logistic regression failed to demonstrate an influence on the increased occurrence of gallbladder polyps for the risk factors of male sex, age, body-mass index (BMI), alcohol, nicotine or caffeine consumption or diabetes mellitus.

CONCLUSION

The prevalence of gallbladder polyps reported in the present study (6.1 %) is higher than figures previously published for populations in Germany or Europe. The majority of polyps were pedunculate and solitary. A typical risk factor profile for gallbladder polyps could not be identified in the present population sample.

Comparison of panorama ultrasonography, conventional B-mode ultrasonography, and computed tomography for measuring liver size

PURPOSE

The objective of the present study is to compare the utility of extended field-of-view ultrasonography and conventional B-mode ultrasonography for determining liver size.

MATERIALS AND METHODS

The liver size in the medioclavicular line (MCL) was determined in 104 inpatients (females: n = 47; males: n = 57) using both ultrasound methods (Philips HDI 5000). The liver size measured in computed tomography (CT; MX 8000 IDT, Philips) served as the gold standard. The body mass index (BMI), ultrasound scanning conditions, and hepatomegaly identified by CT were evaluated as possible factors affecting the measurement accuracy of the sonographic methods.

RESULTS

The standard deviation of the differences between the measured pairs of values shows less dispersion in B-mode ultrasonography (18.7 mm) than panorama ultrasonography (20.8 mm). The mean value of differences between the measured pairs (bias) in the ultrasonographic methods compared to CT is considerably higher in panorama sonography (15.3 mm; SD = 20.8) than in B-mode ultrasonography (0.27 mm; SD = 18.7). A paired t-test of the mean values shows a significant difference between the ultrasonographic methods (p < 0.0001). In diagnosing or excluding hepatomegaly, B-mode sonography is consistent with CT findings in 84 (80.8 %) of 104 patients and panorama ultrasonography is consistent with CT findings in 77 (74.0 %) of 104 patients. Ultrasonographic methods show moderate agreement with each other (Kappa = 0.4265). Higher BMI and limited scanning conditions lead to an increase in the mean difference of measured pairs of values (bias) as well as to an increase in standard deviation of the differences (dispersion).

CONCLUSION

The determination of liver size in the medioclavicular line using panorama ultrasonography often leads to the false-positive diagnosis of hepatomegaly. Therefore, the method should not be recommended for routine diagnostic scans. In cases of significant hepatomegaly, however, panorama ultrasonography offers superior visualization compared to conventional B-mode ultrasonography.

Prevalence and risk factors of focal sparing in hepatic steatosis

PURPOSE

The prevalence, localization and potential risk factors for focal sparing were prospectively assessed in subjects with sonographically detectable hepatic steatosis as part of a population-based cross-sectional study.

MATERIALS AND METHODS

A total of 1,624 persons (n = 906 women; n = 718 men) were evaluated using ultrasonography, laboratory testing and a standardized questionnaire. The following were excluded from the analysis: subjects with reported alcohol consumption > 40 g/day (males) or > 20 g/day (females), those with known chronic hepatitis B or C infection, elevated serum transaminases (AST: m > 44 U/l, f > 33 U/l; ALT: m > 45 U/l, f > 35 U/l) and prior right nephrectomy.

RESULTS

The prevalence of focal sparing in patients with hepatic steatosis (grade I) was 25.6 % for men and 13.0 % for women. In patients with grade II/III disease, the prevalence was 70.9 % for men and 77.6 % for women. The most common site of focal sparing was in segment IV. The average diameter was 22.3 mm (range 7 - 84 mm). No correlation was found for postulated risk "age" (p = 0.09) or "status post cholecystectomy" (p = 0.09). Male sex (p = 0.02) and metabolic syndrome (odds ratio, 2.1; 95 % confidence interval, 1.1 - 4.1; p = 0.02) were confirmed as risk factors.

CONCLUSION

Sonographic evidence of focal sparing in subjects with hepatic steatosis is associated with an increased risk for metabolic syndrome and may be an easily obtained diagnostic criterion in routine clinical settings.

Comparison of contrast-enhanced power Doppler ultrasound (Levovist) and computed tomography in alveolar echinococcosis

BACKGROUND

To date, no study has compared unenhanced and contrast-enhanced (Levovist) power Doppler ultrasound with three-phase helical computed tomography (CT) for the analysis of the vascularization of hepatic lesions in patients who have alveolar echinococcosis.

METHODS

Fifteen patients (11 female and four male; average age, 45.8 years) with confirmed Echinococcus multilocularis infection underwent unenhanced and contrast-enhanced (Levovist) power Doppler ultrasound (2- to 5-MHz transducer head) and three-phase helical CT. The largest identified lesion in each patient was studied.

RESULTS

CT visualized vascularization peripheral or central to the largest echinococcal lesions in 11 of 15 patients. Vascularization in the area of the echinococcal lesions was not visualized by unenhanced or contrast-enhanced power Doppler ultrasound in any of the 15 patients studied.

CONCLUSION

Three-phase helical CT visualizes the vascularization associated with Echinococcus multilocularis lesions in the liver. Neither unenhanced nor contrast-enhanced ultrasound in power mode is suitable for this application.

[Intestinal wall vascularisation in Crohn's disease]

BACKGROUND AND AIMS

In a pilot study the semi-quantitative classification of intestinal wall vascularisation as proposed by Limberg was evaluated.

PATIENTS AND METHODS

20 patients with confirmed Crohn's disease and clinical activity (10 male, 10 female, mean age 30.0 +/- 7.72 years, range 21 - 49 years, mean time since onset of disease 4.6 years, range 0 - 15 years) were included. CDAI, CRP, ESR, and the blood count were evaluated. Two and six weeks after inclusion into the study these examinations were repeated. All patients were treated with anti-inflammatory drugs. The intestinal wall thickness was measured with ultrasound. The vascularisation following the Limberg classification and the number of blood vessels per square centimetre were assessed in the power-Doppler mode.

RESULTS

The mean length of bowel segments with increased wall thickness (> 3 mm) at the beginning of the study was 20.3 cm (range 5 - 50 cm), the mean intestinal wall diameter 5.9 mm (range 4 - 9 mm). The mean density of blood vessels in the power-Doppler mode was 3.8 vessels/cm (2) (range 0 - 8 vessels/cm (2)), the median of Limberg levels was 2 (range 1 - 4). The density of blood vessels per cm (2) well correlated with the Limberg classification throughout the study (r = 0.2 at start; r = 0.94 at 1st follow-up; r = 0.91 at 2nd follow-up).

CONCLUSION

The classification for measuring intestinal wall vascularisation semi-quantitatively (as proposed by Limberg) proved to be easily applicable in routine sonography. Besides the measurement of intestinal wall thickness, activity indices, clinical and laboratory parameters, it may constitute an additional means for evaluation of disease activity.