First results of endocavity evaluation of the microvascularization of malignant prostate tumors using contrast enhanced ultrasound (CEUS) including perfusion analysis: first results

AIM

Detection of prostate cancer lesions using transrectal contrast enhanced ultrasound (CEUS) of the prostate utilizing quantitative perfusion analysis.

METHOD

20 patients (mean age 63 years, 47-71) with biopsy proven prostate cancer underwent transrectal ultrasound (TRUS) prior to radical prostatectomy by 2 experienced examiners using a multifrequency endocavitary probe (5-9 MHZ, LOGIQ E9, GE Healthcare, Chalfont St Giles, UK) to detect cancer-suspect lesions. CEUS was performed dynamically up to 3 Min after bolus injections of 2.4 ml SonoVue® (BRACCO, Italy). Digital cine loops were analyzed by an independent blinded examiner using perfusion quantification software with colour-coded parametric images in order to define suspect regions based on the perfusion-related parameters early wash in rate (WIR), mean transit time (MTT) and rise time (RT). The results of CEUS perfusion analysis were compared with the histopathology after surgery, obtained from whole mount sections.

RESULTS

After prostatectomy and histopathology, 34 prostate cancer foci were found in 20 patients. In 30/34 cases an early enhancement within the tumor was detected by CEUS perfusion analysis without early wash out. By evaluating the MTT and RT tumor detection was possible in 29/34 and 25/34 cases. The highest detection rate of prostate cancers was obtained by analysis of early contrast enhancement (priot to the normal prostate parenchyma), with a sensitivity of 88%, specificity 100%, NPP 60%, PPV 90%, in clinically suspicious cases with good correlation to the postoperative histopathological findings (r = 0.728).

CONCLUSION

This pilot study demonstrates, that quantitaive analysis of perfusion parameters obtained with transrectal CEUS could be helpful for characterization of neoplastic microcirculation of prostate cancer, for preoperative localization of cancer-suspect areas and for therapy guidance and management.

Percutaneous irreversible electroporation (IRE) of hepatic malignant tumours: contrast-enhanced ultrasound (CEUS) findings

PURPOSE

The aim of this study is to describe the image findings of contrast-enhanced ultrasound (CEUS) after irreversible electroporation (IRE), and to assess its usefulness in relation to the evaluation of the ablation status using a dynamic recording of the microvascularisation.

MATERIAL AND METHOD

In this prospectively designed study, a percutaneous IRE was performed for the treatment of malignant hepatic lesions in a total of 15 patients following the interdisciplinary diagnosis. The lesions were documented using CEUS before, immediately after and 20 minutes after the ablation. The acquired CEUS image data was subsequently independently retrospectively evaluated by 2 experienced radiologists and assessed in relation to microvascularisation using a 5 point scale.

RESULTS

Using CEUS, a significant reduction in the microcirculation of the lesions, both centrally and marginally, could be detected following IRE (p < 0.001 and p < 0.001). The mean evaluation of the central microcirculation was reduced from 3.13 ± 1.38 to 0.47 ± 0.64 (p < 0.01). For the peripheral area of the lesion and the ablation margin, there was a reduction of 3.37 ± 1.13 to 1.57 ± 0.46 (p = 0.001). There was no significant reduction in the macrocirculation.

CONCLUSION

Within the framework of this study, it could be demonstrated that, in the course of IRE, a rapid significant reduction of the microcirculation in the ablation area occurred.

Quantitative assessment of bone microvascularization after osteocutaneous flap transplantation using contrast-enhanced ultrasound (CEUS)

BACKGROUND

Extensive wound defects frequently have to be covered by free flap transplantation. A monitoring device for measuring capillary level perfusion of bone is currently not available.

OBJECTIVE

The aim of the study was to detect complications after osteocutaneous flap transplantation using contrast-enhanced ultrasound (CEUS). Additionally quantitative analysis was performed by special perfusion software (QONTRAST®; Bracco, Italy).

METHODS

22 patients were examined after osteocutaneous flap transplantation during the first 72 h after operation. CEUS was performed with a linear transducer (6-9 MHz, LOGIQ E9/GE) after bolus injections of 2.4 ml ultrasound contrast agent (SonoVue®; Bracco, Italy). The osseous perfusion and soft tissue perfusion were analyzed separately and quantitative perfusion analysis was performed. Five patients had to undergo reoperation due to compromised flap microvascularization.

RESULTS

In all 5 complications reduced osseous and soft tissue perfusion was seen using CEUS. Additionally using the perfusion parameters TTP (time to PEAK), RBV (regional blood volume), RBF (regional blood flow) und MTT (mean transit time), significantly lower soft tissue and osseous perfusion was detected.

CONCLUSION

CEUS seems to be capable of detecting vascular disturbances and of assessing microvascularization of the osseous component after osteocutaneous flap transplantation.

Highly efficient localization of pathological glands in primary hyperparathyroidism using contrast-enhanced ultrasonography (CEUS) in comparison with conventional ultrasonography

INTRODUCTION

Preoperative detection of parathyroid gland adenoma in the presence of primary hyperparathyroidism (pHPT) represents a diagnostic challenge. We present the first prospective study with contrast-enhanced ultrasonography (CEUS) as the central diagnostic tool for the preoperative localization of parathyroid gland adenoma in pHPT in comparison with conventional ultrasonography.

METHODS

Between July 2010 and December 2011, 75 consecutive patients underwent surgery for pHPT. In all patients, conventional ultrasonography and CEUS were performed prospectively for localization of pathological parathyroid glands. Twenty-five patients suffered from a concomitant goiter (CG), and 12 patients had undergone previous neck surgery due to thyroid pathologies. The sensitivity of both diagnostic tools was analyzed in comparison with intraoperative and histological findings.

RESULTS

CEUS had a sensitivity of 97% for the detection of the correct quadrant of the pathological parathyroid gland and of 99% for the correct side in comparison with 70% for conventional ultrasonography. In multivariate regression analysis, CG, gland size, and body mass index had a relevant impact on incorrect findings by conventional ultrasonography as compared with CEUS. Follow-up with a minimum of 6 months after surgery showed normal serum levels of calcium and PTH in all 75 patients.

CONCLUSIONS

CEUS represents a highly reliable, noninvasive and nonradioactive diagnostic tool for localization of pathological parathyroid glands in patients with pHPT. Even in the presence of CG, previous neck surgery, or double adenomas, CEUS has a high sensitivity.

Tissue-specific expression of occludin, zona occludens-1, and junction adhesion molecule A in the duodenum, ileum, colon, kidney, liver, lung, brain, and skeletal muscle of C57BL mice

Tight junctions are the most apically positioned intercellular junction and play many roles such as securing adjacent cells, forming barriers from extracellular materials, and facilitating paracellular transport. Occludin and junction adhesion molecule A (JAM-A) are classified as transmembrane proteins that are directly involved in paracellular transport. Zona occludens-1 (ZO-1) is a protein that contains a PDZ domain which forms a binding site for other tight junction proteins. In this study, we assessed the differential expression of these tight junction components in various mouse organs including the intestine (duodenum, ileum, and colon), kidney, liver, lung, brain, and skeletal muscle. Realtime PCR and Western blot assays were performed to measure the gene and protein expression of occludin, JAM-A, and ZO-1. Similar levels of occludin gene expression were detected in all tissues except for skeletal muscle in which occludin expression was not found. The JAM-A and ZO-1 genes were highly expressed in all the tested tissues. Localization of occludin, JAM-A, and ZO-1 was determined by immunohistochemistry. These proteins were detected in the intercellular apical junctions in each tissue except for occludin (which was not observed in skeletal muscle). These immunostaining data were consistent with the gene expression profiles we obtained. Our results suggest that occludin, JAM-A, and ZO-1 genes are normally expressed in the intestine, kidney, liver, lung, and brain indicating that these factors may be essential for maintaining appropriate physiological concentration of ions, solutes and water.

Sonoelastography can be used to monitor the restoration of Achilles tendon elasticity after injury

PURPOSE

The aim of the current study was to evaluate an ultrasound approach for depicting elastic recovery after stem cell application on injured Achilles tendons.

MATERIALS AND METHODS

A rabbit Achilles tendon injury model was used and randomized hind limbs received an extracellular matrix either with autologous mesenchymal stem cells (group 2, n = 6) or without (group 3, n = 6). The cells were harvested from the rabbits' nuchal fat body. Untreated Achilles tendons (group 1, n = 6) served as controls. Specimens were harvested after 8 weeks and analyzed longitudinally for elasticity using a high resolution 6-15 MHz matrix linear probe. For each tendon, real-time color-coded sonoelastography sequences were recorded for 20 seconds and 10 color histogram frames were obtained. Defined regions of interest (ROIs) were placed on the injury (n = 3) and on the adjacent uninjured tendon tissue (n = 3). In total, 180 measurements were obtained for semi-quantitative analysis.

RESULTS

Repeated measures ANOVA demonstrated a higher elasticity for the stem cell-seeded matrix (group 2) in comparison to the unseeded matrix (group 3) (p < 0.001). No significant difference was found between the injured tendon tissue treated with stem cell-seeded matrix (group 2) and the uninjured Achilles tendons (group 1) (p > 0.05). Moreover, no differences were found between the measurements at different points in time (p > 0.05).

CONCLUSION

Our results indicate that autologous mesenchymal stem cell application successfully restores the mechanical properties of injured tendon tissue. Furthermore, sonoelastography makes it possible to monitor the elasticity of injured Achilles tendons.

Ultrasound analyses, anatomical considerations, and clinical experience with the peroneus brevis muscle flap

This ultrasound study investigated the frequency, location, and diameter of segmental blood supply of 34 lower legs in relation to muscle size. Furthermore, we investigated the possibilities and constraints of distally pedicled peroneus brevis muscle flaps, which allow defect coverage down to the medial as well as the lateral ankle. In the proximal part of the peroneus brevis muscle, blood is supplied by branches from the anterior tibial artery that perforate the anterior intermuscular septum; in the distal part of the muscle, blood is supplied by branches from the peroneal artery that perforate the posterior intermuscular septum. All lower legs showed at least one perforating vessel penetrating the posterior intermuscular septum. In all, 32.4% of the legs showed two perforators and 17.6% three perforators. The average position of the most distal perforator was 4.8cm proximal to the tip of the malleolus lateralis. Based on this blood supply, muscle tissue measuring up to 15-20cm can be harvested and rotated by 180° to cover defects of the lower ankle. Our ultrasound study is supplemented by an anatomical dissection and two clinical cases of successful defect coverage with the distally pedicled peroneus muscle flap.

Additional effects of bisphenol A and paraben on the induction of calbindin-D(9K) and progesterone receptor via an estrogen receptor pathway in rat pituitary GH3 cells

There are concerns about the combined estrogenic effects of chemicals since mixtures of these chemicals exist in our environment. This study investigated potential additional interactions between bisphenol A (BPA) and isobutylparaben (IBP), which are major xenoestrogens used in the manufacture of plastics, cosmetics, drugs, and other products. The combined effects of these two chemicals were analyzed by measuring the expression of calbindin-D(9k) (CaBP-9k) in rat pituitary cancer GH3 cells. GH3 cells were treated with single and combination doses of both chemicals (BPA single doses: 10(-7), 10(-6) and 10(-5) M; IBP single doses: 10(-7), 10(-6) and 10(-5) M, and each of the BPA and IBP doses combined). Prior to treatment, cells were temporarily transfected with a plasmid containing an ERE-luciferase reporter gene. Luciferase activity was measured as an indicator of ER activation by 17β-estradiol (E2), BPA, and IBP. BPA (10(-5) M) combined with IBP (10(-7) M and 10(-6) M) induced a significant increase in the luciferase activity. Twenty-four hours after treatment, dose-dependent effects were observed in both single and combined dose groups, and several combination doses induced significant increases in the expression of CaBP-9k and progesterone receptor (PR) at both transcriptional and translational levels. Pre-treatment with ICI 182,780, a pure estrogen antagonist, significantly reversed BPA- and IBP-induced CaBP-9k and PR upregulation in GH3 cells. Taken together, these results indicate that BPA and IBP may have additionally increased estrogenic potency via an estrogen receptor-mediated pathway.

Contrast enhanced ultrasound (CEUS) and time intensity curve (TIC) analysis in compartment syndrome: first results

OBJECTIVE

Purpose of this study was to monitor changes of microcirculation in acute compartment syndrome using contrast enhanced ultrasound (CEUS) and to assess the modified perfusion with a special quantification software.

METHODS

8 patients with trauma of the lower limb or the upper extremity were enrolled after acute compartment syndrome was diagnosed clinically and by intracompartmental pressure measurement. The qualitative analysis of the corresponding compartment was assessed using B-scan mode and CEUS simultaneously. CEUS was performed using a multifrequence probe (6-9 MHz, LOGIQ E9 GE) after a i.v. bolus injection of 2 × 2.4 ml contrast agent (SonoVue(®), Bracco, Italy). Digital raw data were stored as cine loops up to 2 minutes. Retrospectively semiquantitative perfusion analysis was performed using time intensity curve analysis and the quantification software QONTRAST(®).

RESULTS

6 out of 8 patients had to be operated due to clinical symptoms and to a pressure perfusion gradient lower than 30 mm Hg. 2 out of 8 were treated conservatively. In all patients haematomas were seen in B-scan mode. No necrosis could be detected. In the TIC analysis low levels of time to peak (20.0 ± 12.1) and area under the curve (118.4 ± 87.8) were observed in acute compartment syndrome. Similarly results have been obtained using the perfusions parameter PEAK (11.1 ± 5.7), time to PEAK (14.7 ± 9.7), regional blood volume (257.1 ± 192.6), and regional blood flow (12.1 ± 6.5) in QONTRAST(®) perfusion software.

CONCLUSION

CEUS may be capable of differing between acute compartment syndrome and imminent compartment syndrome.

Bedside diagnosis of pleural effusion with a latest generation hand-carried ultrasound device in intensive care patients

BACKGROUND

Further development established hand-carried ultrasound (HCU) imagers in daily clinical workflow providing several advantages such as fast bedside availability and prompt diagnosis.

PURPOSE

To evaluate the diagnostic yield of a latest generation HCU imager compared to chest radiography (CR) for the detection of pleural effusion (PE) in intensive care patients.

MATERIAL AND METHODS

Forty-eight hemithoraces of 24 patients on surgical intensive care units were enrolled in this study. All hemithoraces were evaluated using both HCU and CR. Definite diagnosis of PE was achieved using a high-end ultrasound system as standard of reference. Statistical analysis was performed using 2 × 2 tables and a McNemar test. A P value of <0.05 was considered statistically significant.

RESULTS

PE was present in 35 of 48 hemithoraces (73%). The HCU examination was carried out technically successfully in all hemithoraces. Sensitivity and specificity of HCU for the diagnosis of PE was 91% and 100%, respectively, whereas sensitivity and specificity of CR was 74% and 31%, respectively. The difference between HCU and CR was statistically significant with respect to specificity but not sensitivity (P = 0.008 and P = 0.11, respectively).

CONCLUSION

Due to its ease of use and its high diagnostic yield HCU systems of the latest generation constitute a helpful technique for the primary assessment of PE.

Contrast-enhanced ultrasound for differential diagnosis of suspected GvHD in patients after allogeneic transplantation

GvHD is a serious complication in patients after allo-SCT, presenting with unspecific symptoms such as abdominal pain or cramps and diarrhea. Early diagnosis of GvHD, after differentiation from other causes leading to the same symptoms, such as viral or bacterial enteritis, is highly important because the time needed for diagnosing GvHD is directly correlated to a worsening of the outcome. We examined 23 patients presenting with the abdominal symptoms mentioned above, of whom 20 had received an allo-SCT in their history and were thus potential candidates for enteric GvHD. The other three patients were included because they also presented with abdominal symptoms similar to those of GvHD, which could be ruled out due to their history. We wanted to evaluate CEUS in these patients as an additional subgroup to gain more data on the value of CEUS in early detection of enteral GvHD and in the differentiation of GvHD against other causes of abdominal discomfort. All patients underwent CEUS with particular attention to penetration of the intravenously applied microbubbles in the bowel lumen. In the patients having allo-SCT in their history we strove to achieve histological confirmation of GvHD of the GI-tract. The resulting examinations were documented digitally. Out of 17 patients with confirmed GvHD of the GI tract, 14 showed penetration of the intravenously applied microbubbles into the bowel lumen, leading to a sensitivity and specificity of 82% and 100% for transmural bubble penetration for GvHD of the GI-Tract, since the patients without GvHD of the GI tract showed no transmural bubble penetration. In patients with viral or bacterial infections of the GI tract, no transmural penetration of the microbubbles into the bowel lumen was observed. For microbubble penetration as a criterion for GvHD of the GI-Tract, this leads to a negative predictive value (NPV) of 67%, and a positive predicative value (PPV) of 100%.

Osteocutaneous free flaps: a critical analysis of quantitative evaluation of bone microcirculation with contrast-enhanced high resolution ultrasound (hrCEUS) and TIC analysis

PURPOSE

Osteocutaneous free flaps (OFF) are widely used to reconstruct large bone defects in trauma and cancer surgery. Currently no monitoring method is available to detect blood circulation around and inside the bone after transplantation. Therefore we used for the first time contrast-enhanced high-resolution ultrasound (hrCEUS) to gain evidence for the microcirculation of the transplanted bone.

MATERIALS AND METHODS

15 patients transplanted with OFF because of large bone defects at different sites were examined postoperatively with hrCEUS with a high resolution linear probe (6-9 MHz, LOGIQ E9/GE) and a bolus injection of 2.4 ml of contrast agent (SonoVue®, Bracco, Italy). Operation and examination were performed by either an experienced plastic surgeon or an experienced ultrasound examiner. Microcirculation of the periost and bone was analyzed in different regions of interest (ROIs) and quantitative microcirculation analysis was performed using time intension curve analysis (TIC). We further analyzed clinical outcome of the patients in respect to revision-surgery, necrosis of the OFF and flap survival as well as viability on standard x-rays 2 months after surgery.

RESULTS

The most representative parameter by TIC analysis of hrCEUS were the area under the curve (AUC) and the time to peak (Ttop). The AUC of the periost and central part of the bone showed a high correlation (Pearson's r = 0.831). Mean AUC for the periost was 163.92 dB ± 49.44 and for the central part of the bone 70.42 dB ± 25.33. The Ttop of the periosteal ROI was 33.04 sec. ± 6.71 and the bone ROI 41.01 sec. ± 9.24. There was a high correlation of the Ttop of the periost and bone (Pearson's r = 0.937). One revision had to be performed due to haematoma and microcirculation defect of the distal part of the transplanted bone graft which was detected early by hrCEUS and the distal part of the avital bone could be removed timely.

CONCLUSION

For the first time we could show that hrCEUS is a reliable method to evaluate the viability of OFF. The AUC and Ttop seem to be a valuable parameter to detect the microcirculation around and inside the bone transplant.

Image fusion of contrast enhanced ultrasound (CEUS) with computed tomography (CT) or magnetic resonance imaging (MRI) using volume navigation for detection, characterization and planning of therapeutic interventions of liver tumors

AIM

To evaluate, whether image fusion of contrast enhanced ultrasound (CEUS) with CT or MRI affects the diagnosis and characterization of liver lesions or the therapeutic strategy of surgical or interventional procedures compared to the preliminary diagnosis.

MATERIAL AND METHODS

In a retrospective study the image fusion scans of CEUS with contrast enhanced CT or MRI of 100 patients (71 male, mean age 59 years, 0.3-85 years) with benign or malignant liver lesions were evaluated. Fundamental B-scan, color Doppler imaging and CEUS were performed in all patients by an experienced examiner using a multifrequency convex transducer (1-5 MHz, LOGIQ 9/GE) and volume navigation (Vnav). After a bolus injections of up to 2.4 ml SonoVue® (BRACCO, Italy) digital raw data was stored as cine-loops up to 5 min. In 74 patients, CEUS was fused with a pre-existing ceCT, in 26 patients a ceMRI was used.

RESULTS

In all 100 patients (100%) the image quality in all modalities (ceCT, ceMRI and CEUS) was excellent or with only minor diagnostic limitations. Regarding the number of lesions revealed in image fusion of CEUS/ceCT/ceMRI and the preceding diagnostic method, concordant results were found in 84 patients. In 12 patients, additional lesions were found using fusion imaging causing subsequently a change of the therapeutical strategy. In 15 out of 21 patients with either concordant or discordant results regarding the number of lesions, image fusion allowed a definite diagnosis due to a continuous documentation of the microcirculation of the tumor and its contrast enhancement. A significant coherency (p < 0.05) among image fusion with either ceCT or ceMRI and CEUS and a subsequent change of therapeutic strategy was found.

CONCLUSION

Image fusion with volume navigation (VNav) of CEUS with ceCT or ceMRI frequently allows a definite localization and diagnosis of hepatic lesions in patients with primary hepatic carcinoma or metastatic diseases. This might cause a change of the therapeutic strategy in many patients with hepatic lesions.

Contrast-enhanced ultrasound improves real-time imaging of ablation region during radiofrequency ablation: preliminary results

PURPOSE

To assess the added value of depicting tumour microvascularisation, using dynamic contrast enhanced (CEUS), during radiofrequency ablation, as a means of achieving a complete ablation (CA) of malignant liver lesions.

MATERIAL AND METHODS

18 consecutive patients (2 female, 16 male, age range 52-79 years, mean 64.1 ± 9.9 years) with 22 histologically confirmed hepatic malignancies (HCC: n = 10, liver metastases: n = 12) underwent RFA. Before RFA treatment, conventional US, CEUS and contrast enhanced CT (ceCT) of the liver were performed. During the CT-guided RFA procedure, CEUS was performed to asses the ablation defect. In case of partial ablation a subsequent ablation was performed with a corrected electrode position and evaluated again using CEUS. This procedure was repeated until a CA was achieved. The number of ablations per patient was recorded. Secondary efficacy parameters assessed were lesion detectability in the different imaging modalities and contrast phases.

RESULTS

Overall intraprocedural CEUS led to a change in therapeutic management in 59% of cases, resulting in 17 additional ablation cycles. Lesion detectability during CT Fluoroscopy was the sole statistical significant predictor of incomplete ablations (p = 0.008). The mean number of ablations for detectable lesions was 1.27 vs. 2.27 ablations for not detectable lesions (p = 0.002). The combined CT and CEUS RFA procedure led to a CA for all treated lesions in follow up 3 month post intervention.

CONCLUSION

CEUS does allow a reliable and immediate assessment of therapeutic efficacy of percutaneous RFA procedures of malignant liver lesions, through the continuous dynamic evaluation of tumour microcirculation.