Contrast enhanced ultrasound in the evaluation and percutaneous treatment of hepatic and renal tumors

Safety Analysis of Adverse Events of Ultrasound Contrast Agent Lumason/SonoVue in 49,100 Patients

This study assessed the incidence of mild, moderate and severe adverse events (AEs) and examined their association with age, sex, body region examined, time to event and duration of the AE(s) in a large cohort of patients who underwent contrast-enhanced ultrasound (CEUS) with Lumason/SonoVue. In this retrospective observational study, 49,100 patients who underwent CEUS were analyzed. Forty-three (0.088%) patients experienced AEs, with 23 (0.047%) patients experiencing mild AEs, 13 (0.026%) experiencing moderate AEs and 7 (0.014%) experiencing severe AEs. No fatal event occurred. There was no age- or sex-related difference in the incidence of the AE(s) (p = 0.158 and p = 0.474). Inpatients (0.17%) more often experienced AEs than outpatients (0.06%, p = 0.003). The mean time to event for mild and moderate AEs was 14.50 ± 6.96 and 15.75 ± 10.40 min, respectively, whereas that for severe AEs was 1.89 ± 1.21 min after the injection. The remission time for mild and moderate AEs was approximately 30-40 min, and all patients with severe AEs recovered within 12 h. Twenty-one (48.8%) patients received medical treatment. In summary, Lumason/SonoVue has a good safety profile with a low incidence of AEs, most of which are mild with a short time to event and duration.

Fabrication of SEBS Block Copolymer-Based Ultrasound Phantom Containing Mimic Tumors for Ultrasound-Guided Needle Biopsy Training

The creation of various phantoms is important in medical education, especially for intern physicians who need to practice their skills. Ultrasound phantoms are particularly useful for training in ultrasound-guided needle biopsy. SEBS, or poly(styrene-ethylene-butylene-styrene), is a thermoplastic elastomer that can be used with mineral oil to make ultrasound phantoms and a tumor-like structure. SEBS block copolymer-based phantoms are inexpensive, non-toxic and shelf-stable, and are easy to modulate. Most importantly, such ultrasound phantoms have acoustic and mechanical properties similar to those of human soft tissues. The quality of ultrasound images of phantoms and mimic tumors is excellent and can be maintained even after several biopsy needle punctures, making them excellent ultrasound phantoms for physician practice as needed.

Microwave Ablation of Liver, Kidney and Lung Lesions: One-Month Response and Manufacturer’s Charts’ Reliability in Clinical Practice

Microwave ablation systems allow for performing tumoral destruction in oncology. The objective of this study was to assess the early response and reliability of the microwave ablation zone size at one month for liver, kidney and lung lesions, as compared to the manufacturer’s charts. Patients who underwent microwave ablation with the Emprint^TM ablation system for liver, kidney and lung lesions between June 2016 and June 2018 were retrospectively reviewed. Local response and ablation zone size (major, L, and minor, l, axes) were evaluated on the one-month follow-up imaging. Results were compared to the manufacturers’ charts using the Bland–Altman analysis. Fifty-five patients (mean age 68 ± 11 years; 95 lesions) were included. The one-month complete response was 94%. Liver ablations showed a good agreement with subtle, smaller ablation zones (L: −2 ± 5.7 mm; l: −5.2 ± 5.6 mm). Kidney ablations showed a moderate agreement with larger ablations for L (L: 8.69 ± 7.94 mm; l: 0.36 ± 4.77 mm). Lung ablations showed a moderate agreement, with smaller ablations for l (L: −5.45 ± 4.5 mm; l: −9.32 ± 4.72 mm). With 94% of early complete responses, the system showed reliable ablations for liver lesions, but larger ablations for kidney lesions, and smaller for lung lesions.

Contrast-enhanced ultrasonography to guide diagnostic and therapeutic interventional procedures

Although not necessary for the vast majority of ultrasound-guided procedures, intravenous contrast agents can be useful for procedures aimed at lesions that require contrast enhancement to be seen on ultrasonography. Using contrast-enhanced ultrasonography to guide procedures has two drawbacks: first, because enhancement from ultrasound contrast agents is short lived, it is often necessary to plan several injections; second, because the needle is poorly seen on contrast-enhanced ultrasonography, a dual image display format is necessary. Contrast-enhanced ultrasonography can be used for planning and monitoring diagnostic and therapeutic procedures, for guiding the procedures, and for follow-up. Using contrast-enhanced ultrasonography enables better results in both types of procedures; moreover, it can be used within cavities.

Role of Contrast-Enhanced Ultrasound in the Detection of Complications After Ultrasound-Guided Liver Interventional Procedures

The role of contrast-enhanced ultrasound (CEUS) in interventional ultrasound-guided procedures in the liver has been increasingly recognized. However, little is known about the capability of CEUS for diagnosing complications after liver biopsy and ablation with special regard to postprocedural hemorrhage. The aim of this Pictorial Essay is to present the CEUS features of a wide spectrum of vascular complications (with or without bleeding) and injuries of the surrounding abdominal and chest wall occurring after liver interventional procedures.

Differential Imaging of Liver Tumors before and after Microwave Ablation with Electrode Displacement Elastography

Liver cancer is a leading cause of cancer-related deaths; however, primary treatment options such as surgical resection and liver transplant may not be viable for many patients. Minimally invasive image-guided microwave ablation (MWA) provides a locally effective treatment option for these patients with an impact comparable to that of surgery for both cancer-specific and overall survival. MWA efficacy is correlated with accurate image guidance; however, conventional modalities such as B-mode ultrasound and computed tomography have limitations. Alternatively, ultrasound elastography has been used to demarcate post-ablation zones, yet has limitations for pre-ablation visualization because of variability in strain contrast between cancer types. This study attempted to characterize both pre-ablation tumors and post-ablation zones using electrode displacement elastography (EDE) for 13 patients with hepatocellular carcinoma or liver metastasis. Typically, MWA ablation margins of 0.5-1.0 cm are desired, which are strongly correlated with treatment efficacy. Our results revealed an average estimated ablation margin inner quartile range of 0.54-1.21 cm with a median value of 0.84 cm. These treatment margins lie within or above the targeted ablative margin, indicating the potential to use EDE for differentiating index tumors and ablated zones during clinical ablations. We also obtained a high correlation between corresponding segmented cross-sectional areas from contrast-enhanced computed tomography, the current clinical gold standard, when compared with EDE strain images, with r2 values of 0.97 and 0.98 for pre- and post-ablation regions.

Clinical value of contrast-enhanced ultrasonography in focal hypoechogenic lesions of thyroid

OBJECTIVE

The objectives of this study were to analyze the accuracy of contrast-enhanced ultrasonography (CE-US) in diagnosing focal hypoechogenic lesions of the thyroid (FHLT), and to explore the clinical value of CE-US in the diagnosis of FHLT.

METHODS

Patients undergoing CE-US and ultrasound-guided fine needle aspiration (US-FNA) of FHLT at First Hospital of China Medical University between January 2017 and December 2018 were selected for the study; this included patients with papillary thyroid carcinoma (PTC), subacute thyroiditis (SAT) and focal Hashimoto thyroiditis (FHT). All patients underwent color Doppler ultrasonography (CD-US) after which thyroid image reporting and data system (TI-RADS) grading were done. Then, each patient underwent CE-US and US-FNA. The results of the CE-US were analyzed using descriptive statistics. The cytopathological results from the US-FNAs were the gold standard used to confirm the diagnoses.

RESULTS

A total of 56 patients were selected for the study. In the PTC group (n = 16), grading was as follows: TI-RADS4a, n = 3; TI-RADS4b, n = 12; and TI-RADS4c, n = 1. More patients with PTC showed heterogeneous hypoenhancement (n = 15) than heterogeneous isoenhancement (n = 1) on CE-US. In the SAT group (n = 24), grading was as follows: TI-RADS3, n = 1; TI-RADS4a, n = 18; TI-RADS4b, n = 5. Fewer patients with SAT showed heterogeneous hypoenhancement (n = 2) than heterogeneous isoenhancement (n = 22) on CE-US. In the FHT group (n = 16), grading was as follows: TI-RADS3, n = 1; TI-RADS4a, n = 11; TI-RADS4b, n = 4. Of those in the FHT group, one patient showed heterogeneous isoenhancement, one patient showed heterogeneous hypoenhancement, and 14 showed uniform isoenhancement on CE-US. The diagnostic accuracy of CD-US alone differed significantly from that of CD-US + CE-US (p < 0.05).

CONCLUSION

CE-US has a high diagnostic accuracy for FHLT and can be used to identify PTC, SAT, and FHT.

Percutaneous microwave ablation of renal cell carcinoma: practice guidelines of the ultrasound committee of Chinese medical association, interventional oncology committee of Chinese research hospital association

Imaging-guided percutaneous microwave ablation (MWA) with high thermal efficiency comprises rapid, successful management of small renal cell carcinomas (RCCs) in selected patients. Ultrasound Committee of Chinese Medical Association, Interventional Oncology Committee of Chinese Research Hospital Association developed evidence-based guidelines for MWA of RCCs after systematically reviewing the 1969-2019 literature. Systematic reviews, meta-analyses, randomized controlled trials, cohort, and case-control studies reporting MWA of RCCs were included and levels of evidence assessed. Altogether, 146 articles were identified, of which 35 reported percutaneous MWA for T1a RCCs and 5 articles for T1b RCCs. Guidelines were established based on indications, techniques, safety, and effectiveness of MWA for RCCs, with the goal of standardizing imaging-guided percutaneous MWA treatment of RCCs. Key points Microwave ablation is recommended for managing small renal cell carcinoma in selected patients. Imaging protocols are tailored based on the procedural plan, guidance, and evaluation. Patient's selection evaluation, updated technique information, clinical efficacy, and complications are recommended to standardize management. A joint task force (multidisciplinary team) summarized the key elements of the standardized report.

Contrast-enhanced ultrasonography to guide diagnostic and therapeutic interventional procedures

Although not necessary for the vast majority of ultrasound-guided procedures, intravenous contrast agents can be useful for procedures aimed at lesions that require contrast enhancement to be seen on ultrasonography. Using contrast-enhanced ultrasonography to guide procedures has two drawbacks: first, because enhancement from ultrasound contrast agents is short lived, it is often necessary to plan several injections; second, because the needle is poorly seen on contrast-enhanced ultrasonography, a dual image display format is necessary. Contrast-enhanced ultrasonography can be used for planning and monitoring diagnostic and therapeutic procedures, for guiding the procedures, and for follow-up. Using contrast-enhanced ultrasonography enables better results in both types of procedures; moreover, it can be used within cavities.

Thermal Ablation for Papillary Thyroid Microcarcinoma: How Far We Have Come?

Purpose

Thermal ablation (TA), as one of the most currently remarkable technologies, has achieved great success in many malignant diseases including but not limited to hepatic and renal carcinoma. In recent years, this technology was gradually introduced to the treatment of papillary thyroid microcarcinoma (PTMC) and even papillary thyroid carcinoma (PTC). Thereby, we summarized the current progress of TA development in the treatment of PTMC.

Methods

The latest relevant literature from the PubMed database with keywords "thermal ablation", "papillary thyroid microcarcinoma", "microwave ablation", "radio-frequency ablation", and "laser ablation", among others, were comprehensively reviewed in this article. The follow-up outcomes of patients in these articles were analyzed.

Results

The efficacy and safety of TA including microwave ablation (MWA), laser ablation (LA), and radiofrequency ablation (RFA) in the treatment of PTC and PTC have been intensively studied. Based on existing clinical trials, the relatively long-term follow-up (range, from 6 to 64.2 months) results in MWA, LA, and RFA were satisfactory that tumor volume reduction rate (VRR) reached and even surpass 99%. Compared with routine surgery methods (total thyroidectomy and lobectomy), the incidence rate of complications was relatively lower and the recurrence rate of TA techniques was not statistically significant, whereas the operative time, blood loss, length of hospital stay, and hospital cost were significantly decreased.

Conclusion

TA presents the same satisfactory therapeutic effects but minimal postoperative trauma can significantly improve the patients' quality of life. However, future larger sample, multicenter, and prospective randomized controlled trials are urgently needed to validate the feasibility of TA in dealing with PTMC.

Local recurrence of renal cell carcinoma successfully treated with fusion imaging-guided percutaneous thermal ablation

Image-guided thermal ablations are increasingly applied in the treatment of renal cancers, under the guidance of ultrasound (US) or computed tomography (CT). Fusion imaging allows exploitation of the strengths of all imaging modalities simultaneously, eliminating or minimising the weaknesses of every single modality. We present a case of a 68-year-old patient treated using US/CT fusion imaging to guide radiofrequency ablation for local recurrence of renal cell carcinoma undetectable by ultrasound.

Reproducibility of Ablated Volume Measurement Is Higher with Contrast-Enhanced Ultrasound than with B-Mode Ultrasound after Benign Thyroid Nodule Radiofrequency Ablation-A Preliminary Study

The reproducibility of contrast-enhanced ultrasound (CEUS) and standard B-mode ultrasound in the assessment of radiofrequency-ablated volume of benign thyroid nodules was compared. A preliminary study was conducted on consecutive patients who underwent radiofrequency ablation (RFA) of benign thyroid nodules between 2014 and 2016, with available CEUS and B-mode post-ablation checks. CEUS and B-mode images were retrospectively evaluated by two radiologists to assess inter- and intra-observer agreement in the assessment of ablated volume (Bland–Altman test). For CEUS, the mean inter-observer difference (95% limits of agreement) was 0.219 mL (-0.372–0.809 mL); for B-mode, the mean difference was 0.880 mL (-1.655–3.414 mL). Reproducibility was significantly higher for CEUS (85%) than for B-mode (27%). Mean intra-observer differences (95% limits of agreement) were 0.013 mL (0.803–4.097 mL) for Reader 1 and 0.031 mL (0.763–3.931 mL) for Reader 2 using CEUS, while they were 0.567 mL (-2.180–4.317 mL, Reader 1) and 0.759 mL (-2.584–4.290 mL, Reader 2) for B-mode. Intra-observer reproducibility was significantly higher for CEUS (96% and 95%, for the two readers) than for B-mode (21% and 23%). In conclusion, CEUS had higher reproducibility and inter- and intra-observer agreement compared to conventional B-mode in the assessment of radiofrequency-ablated volume of benign thyroid nodules.

Intracavitary contrast-enhanced ultrasound in ultrasound-guided percutaneous management of abdominal fluid collections/abscesses by a single clinician: an example of point-of-care ultrasound

PURPOSE

To assess the role of intracavitary contrast-enhanced ultrasound (IC-CEUS) as a focused ultrasound (US) examination aimed at supporting a single physician in the management of interventional procedures for abdominal fluid collections/abscesses.

METHODS

In 43 patients (27 M/16 F, median age 68 years, range 35-91), a single physician performed catheter drainage (42) or needle aspiration (3) for the following: 14 infected abdominal fluid collections, 11 non-infected abdominal fluid collections, 9 pyogenic liver abscesses, 8 gallbladder empyema, and 3 infected pancreatic fluid collections. IC-CEUS (0.1-0.2 mL of SonoVue in 20 mL of saline) was carried out during catheter/needle placement and during the follow-up for catheters left in place.

RESULTS

Immediate IC-CEUS allowed to verify the (1) correct positioning of the needle/catheter inside the target in all cases and (2) communication with adjacent structures so as to choose a proper treatment in 21% of the cases. Follow-up IC-CEUS aided in the management of 40 catheters left in place. Appropriate treatment was implemented in 19.3% of the cases because of the presence of biliary fistulas and gallbladder perforation. IC-CEUS helped the physician with the appropriate timing of catheter removal by providing information on catheter malfunction (due to obstruction/dislodgement) and the size of residual undrained cavities. No side effects were registered following IC-CEUS.

CONCLUSION

Even if not strictly performed at bedside, IC-CEUS may represent an example of point-of-care ultrasound since it allows an interventional clinician to assess needle/catheter placement success, make treatment decisions, and choose the optimal timing for catheter removal with low costs and without side effects.

Surgical margin follow-up after nephron-sparing surgery: the possible role of CEUS

PURPOSE

To evaluate the possible role of CEUS in the management of patients who underwent nephron-sparing surgery (NSS) and presented questionable findings on the surgical margins at the CECT follow-up exam.

METHODS

In our retro-prospective study, we included 952 patients with small renal masses (SRMs) treated with NSS between 2012 and 2015 and followed with CECT for at least 3 years at Careggi University Hospital. Twenty-two of them presented solid masses on the site of surgery with questionable enhancement at CECT and were further studied with CEUS. This examination was followed by a quantitative analysis of the enhancement pattern.

RESULTS

Out of the 22 masses, 18 were considered possible granulomas, presenting slow wash-in and low enhancement peaks compared to the surrounding parenchyma and persistent delayed wash-out at CEUS. Four lesions presented a suspicious malignant enhancement pattern, with rapid wash-in, high peak and rapid wash-out. In accordance with instructions from the urologist, the first group of 18 patients was strictly monitored, revealing that the mass dimensions and enhancement pattern were stable for at least 3 years of follow-up, while the other 4 patients underwent a second intervention and their masses were confirmed as tumor recurrence at the histopathological evaluation.

CONCLUSIONS

CEUS can play a key role in the surgical margin follow-up after NSS when a suspicious enhancing mass is detected by CECT, giving an accurate depiction of the enhancement pattern and thus helping the clinician in the management of the patient.

Contrast-Enhanced Ultrasound Guidance for Interventional Procedures

Since its introduction, contrast-enhanced ultrasound (CEUS) has gained an important role in the diagnosis and management of abdominal and pelvic diseases. Contrast-enhanced ultrasound can improve lesion detection rates as well as success rates of interventional procedures when compared to conventional ultrasound alone. Additionally, CEUS enables the interventionalist to assess the dynamic enhancement of different tissues and lesions, without the adverse effects of contrast-enhanced computed tomography, such as exposure to ionizing radiation and nephrotoxicity from iodinated contrast material. This review article describes the various applications and advantages of the use of CEUS to enhance performance of ultrasound-guided interventions in the abdomen and pelvis.

Contrast-enhanced ultrasound for quantification of tissue perfusion in humans

Contrast-enhanced ultrasound is an imaging technique that can be used to quantify microvascular blood volume and blood flow of vital organs in humans. It relies on the use of microbubble contrast agents and ultrasound-based imaging of microbubbles. Over the past decades, both ultrasound contrast agents and experimental techniques to image them have rapidly improved, as did experience among investigators and clinicians. However, these improvements have not yet resulted in uniform guidelines for CEUS when it comes to quantification of tissue perfusion in humans, preventing its uniform and widespread use in research settings. The objective of this review is to provide a methodological overview of CEUS and its development, the influences of hardware and software settings, type and dosage of ultrasound contrast agent, and method of analysis on CEUS-derived perfusion data. Furthermore, we will discuss organ-specific imaging challenges, advantages, and limitations of CEUS.

Association among the R.E.N.A.L. nephrometry score and clinical outcomes in patients with small renal masses treated with percutaneous contrast enhanced ultrasound radiofrequency ablation

Introduction

An association between the R.E.N.A.L. nephrometry score (RNS) and clinical outcomes in patients with a small renal mass (SRM) has been proposed. We analyzed clinical outcomes according to the RNS in patients with a SRM treated with percutaneous contrast enhanced ultrasound (CEUS) radiofrequency ablation (RFA).

Material and methods

Patients with a SRM, who underwent RFA between January 2005 and March 2015, were retrospectively identified. The association between RNS and clinical outcomes was evaluated using parametric and non-parametric analysis.

Results

We analyzed 163 SRMs in 149 consecutive patients. The mean age was 71.7 years. Mean follow-up time was 33.3 months ±20.6 (2-102). The mean RNS was 5.6 ±1.52 (4-11). A total of 121 (74.2%) cases were of low complexity and 42 (25.8%) were medium complexity. We identified 11 cases of tumor persistence (6.7%). The mean RNS was 5.58 in the cases with no persistence and 5.73 in the cases with persistence (p = 0.788). We identified 15 (9.2%) cases of recurrence. The mean RNS was 5.57 ±0.1 (4-11) in the cases without recurrence and 5.73 ±0.4 (4-9) in recurrence cases (p = 0.804). Of the 76 biopsy proven RCC cases, 8 (10.5%) cases of recurrence were observed, 5 in the low complexity group and 3 in the medium complexity group (p = 0.690). A total of 9 (5.5%) cases of complications were observed, with 5 (4.3%) in the low complexity group and 4 cases in the medium complexity group (p = 0.23). The mean length of stay was 1.5 days with a significant difference between low and medium complexity groups (1.3 vs. 2.1 days, p = 0.02). The mean difference between preoperative eGFR and estimated eGFRat 12 months was -3.08 mL / min ±13.3 (-49.4-34.1) and was significant (p = 0.008).However, this variation did not show significant differences between the low and medium complexity groups (p = 0.936). All-cause mortality was 11.7%, 14 cases (11.6%) in the low complexity group and 5 (11.9%) in the medium complexity group (p = 1.0). No cases of renal cell carcinoma (RCC) specific mortality were identified.

Conclusions

The RNS was not associated with tumor persistence, recurrence, cancer specific mortality, complications or renal function 12 months after the first treatment, showing significant difference only in length of hospital stay between low and medium complexity groups.

Abdominal applications of ultrasound fusion imaging technique: liver, kidney, and pancreas

Fusion imaging allows exploitation of the strengths of all imaging modalities simultaneously, eliminating or minimizing the weaknesses of every single modality. Ultrasound (US) fusion imaging provides benefits in real time from both the dynamic information and spatial resolution of the normal US and the high-contrast resolution and wider field of view of the other imaging methods. US fusion imaging can also be associated with the use of different ultrasound techniques such as color Doppler US, elastography, and contrast-enhanced US (CEUS), for better localization and characterization of lesions. The present paper is focused on US fusion imaging technologies and clinical applications describing the possible use of this promising imaging technique in the liver, kidney, and pancreatic pathologies.

Imaging after radiofrequency ablation of renal tumors

The number of percutaneous radiofrequency ablation procedures performed for renal tumors is progressively increasing worldwide. Periodic imaging follow-up has the double role to guarantee the treatment efficacy over time and to early detect any possible complication. Tumor size reductions, as well as the appearance of the characteristic ‘halo sign’, are normal findings that represent good ablative outcomes. However the most reliable factor of ablation efficacy remains the total absence of contrast enhancing zones within the ablated area. The aim of this article is to illustrate the typical aspect of an effective radiofrequency ablation treatment, which are the imaging findings that may suggest the presence of residual tumoral tissue and which are the main early and late procedural complications.

Percutaneous Laser Ablation of Unifocal Papillary Thyroid Microcarcinoma: Utility of Conventional Ultrasound and Contrast-Enhanced Ultrasound in Assessing Local Therapeutic Response

PURPOSE

To investigate the use of conventional ultrasound and contrast-enhanced ultrasound (CEUS) in assessing local therapeutic response of percutaneous laser ablation (PLA) for papillary thyroid microcarcinoma (PTMC).

METHODS

Sixty-four patients with 64 PTMCs who were referred to our hospital from November 2013 to July 2016 were treated with PLA. The extent of ablation was assessed by CEUS at 10-20 min and 7 days after PLA. The size and volume of the ablation zone were evaluated on conventional ultrasound at 1 h, 1, 3, 6 and 12 months, and every half-year thereafter, and recurrences were also recorded. Ultrasound-guided fine needle aspiration biopsy (FNAB) of the ablated area was performed at 1, 6 and 12 months after PLA.

RESULTS

Two incomplete ablations were detected by CEUS, and a second ablation was performed. The mean largest diameter and volume of the ablated area on CEUS at 10-20 min and 7 days after PLA were significantly larger than those of pre-treatment on conventional ultrasound (p < 0.05, for both). At the last follow-up, the mean largest diameter was reduced from 4.6 ± 1.5 to 0.6 ± 1.3 mm (p < 0.0.5), and the average volume was 41.0 ± 40.4 mm³, which decreased to 1.8 ± 6.7 mm³ (p < 0.0.5). A cervical metastatic lymph node was detected on ultrasound and confirmed by ultrasound-guided FNAB at 30 months after PLA.

CONCLUSIONS

CEUS could play a crucial role in assessing the completeness of PLA for treating PTMC, and conventional ultrasound can not only guide the FNAB process but also is important in the follow-up of PTMC after PLA.

Establishment and evaluation of a Beagle model of grade III pancreatic trauma

Pancreatic trauma (PT) is a severe abdominal injury that is often combined with multiple organ injury. It is a severe disease that is difficult to diagnose and has a high mortality rate, particularly for grade III PT. The pathogenesis, disease progress and complications have not been fully investigated due to the lack of a reliable animal model. To address this, a Beagle model of grade III PT was established in the present study using a procedure involving rupture of the main pancreatic duct. Peripancreatic effusions and the degree of pancreatic damage were examined by routine ultrasound and contrast-enhanced ultrasound (CEUS). Also, ascites were collected for the examination of amylase and lipase levels, and whole blood samples were collected for the analysis of amylase, lipase, C-reactive protein (CRP), interleukin (IL)-6 and tumor necrosis factor (TNF)-α levels in the serum. Urine samples were also collected for the examination of trypsinogen activation peptide (TAP). In addition, the pancreas was sectioned and stained with hematoxylin and eosin. In comparison with routine ultrasound, CEUS showed a large area of focal trauma, with a depth greater than half of the anteroposterior diameter of the pancreas, with a clear boundary, clear capsular rupture and trauma induced by active bleeding. The volume of ascites peaked at 48 h post-trauma and decreased thereafter. Amylase and lipase levels in the ascites were elevated at 24 h post-trauma and significantly decreased at 48 and 72 h post-trauma (P<0.01). In addition, serum amylase and lipase levels increased to peak levels at 48 h post-trauma and then decreased (P<0.05), while serum CRP, IL-6 and TNF-α levels peaked at 24 h post-trauma and then decreased (P<0.05). Urinary TAP levels also peaked at 24 h post-trauma and subsequently decreased (P<0.05). At 72 h post-trauma, the pancreatic cells were loosely distributed, with damaged acini, hyperchromatic nuclei and severe inflammatory cell invasion. These results indicated that the Beagle model of grade III PT was satisfactorily established, and that CEUS is potentially useful as an auxiliary diagnosis method for PT. This animal model may be useful for studying the pathogenesis, disease progress and complications of PT.

Monitoring after radiofrequency ablation of liver tumors: contrast-enhanced ultrasound (CEUS) vs. contrast-enhanced computer tomography (CECT), two days after procedure

AIM

Our research evaluated the ability of contrast-enhanced ultrasound (CEUS) and contrast enhanced computer tomography (CECT), performed 48 h after radiofrequency ablation (RFA), to detect residual tumor tissue. As recently published studies have evaluated periprocedural CEUS performed within 24 h after procedure and their results were not satisfactory, it seems that postponing the control test by one day could increase the sensitivity of both methods.

PATIENTS AND METHODS

We evaluated 33 patients with 37 lesions, who met the criteria for our study. The criteria were 1) the treated lesion is sonographically viewable and 2) the patient underwent both CEUS and CECT control 48 h after treatment and additional follow-up 3 months later by CECT. Presence of residual tumor tissue and the size of necrosis were recorded and compared to the results of 3-months CECT.

RESULTS

Nine residues were present in our group. CEUS and CECT showed similar sensitivity (66.7% and 77.8%, respectively) and identical specificity (both 96.4%) for detection of residual tumor tissue. CEUS significantly underestimated the size of necrosis in comparison to CECT (on average by 2.4 mm, P=0.0005). Over the 3-months follow-up period the size of necrosis decreased in all patients (on average by 7.2 mm, P<0.0001).

CONCLUSION

The quality of tumor residue detection in 48-h CEUS was comparable to that of 48-h CECT. This finding suggests the CEUS being a feasible substitute for CECT. Both methods show reasonable sensitivity; therefore this timing seems to be appropriate for the first post-treatment control while also allowing for early retreatment if residual tumor tissue is found.

Update on the role of ultrasound guided radiofrequency ablation for thyroid nodule treatment

Thyroid nodules can be frequently detected in general population, most of them are benign, however malignant cases are rising in the past decades. Ultrasound (US) is the most common imaging modality to assess thyroid nodular lesions, plan patient work-up and guide minimally invasive treatment. The present review paper has been researched to evaluate the current status of radiofrequency ablation (RFA) treatment in order to evaluate indications, techniques, complications, limitations and outcome assessment in benign solid, partially cystic nodules and recurrent malignant nodules. RFA comparison with other ablation techniques has been provided as well. US guided Radiofrequency ablation has been proved to be effective and safe in cases of benign thyroid nodules and a promising treatment method alternative to surgery for patients with recurrent papillary thyroid cancer. It's major role lies in significant reduction of thyroid nodule mean volume and improvement of the patient symptoms. However, future multicenter studies are warranted to better clarify the multi-parametric patient selection criteria and evaluate RFA technique efficacy, advantages and limitations in the variety of thyroid nodular disease.

Contrast-enhanced ultrasonography of the liver using SonoVue

This review focuses on the use of contrast-enhanced ultrasonography (CEUS) with SonoVue (Bracco Imaging) for the diagnosis of focal liver lesions (FLLs), guidance during ablative treatment, and follow-up of liver tumors. Multicenter trials have shown that the performance of CEUS for the characterization of FLLs is similar to that of contrast-enhanced computed tomography or contrast-enhanced magnetic resonance imaging. CEUS with SonoVue has been effectively used for guiding the percutaneous treatment of malignant liver tumors that are invisible or poorly visualized in traditional gray-scale ultrasonography. Postprocedural CEUS may be used to detect and retreat residual viable tissue in the same ablative session. The use of CEUS for the assessment of diffuse liver disease is also discussed.

[Ablative therapy in urology: Good practice and perspective]

INTRODUCTION

To expose the main point of discussion from present ablative therapies' guidelines and propose global perspectives.

MATERIALS AND METHODS

A review of the scientific literature was performed in Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com/) using different associations of keywords "ablative therapy" ; "prostate cancer"; "kidney cancer"; "guidelines"; "hybrid operating room". Publications obtained were selected based on methodology, language and relevance.

RESULTS

Present guidelines on ablative therapies in urology are, considering authors and organs, either particularly prudent (EAU guidelines for prostate and kidney) or relatively optimistic (CIRSE guidelines). This discrepancy is related to a low level of proof. So, a new approach is mandatory: more homogeneous in methodology, and especially more open to a new organization sparing economic efficiency. The objective will be to get multifunctional and multidisciplinaries platforms, in facts and in minds. It will induce, in the future, a deep reflection about training and boundaries' specialties.

CONCLUSION

Ablative therapies represent a crucial stake for urology and a clear example of medicosurgical evolution in future, based on new technologies (energy, robotic, imaging). A serious and deep reflection is necessary to prepare it and be deeply involved in.

Dynamic Contrast-Enhanced Ultrasound of Colorectal Liver Metastases as an Imaging Modality for Early Response Prediction to Chemotherapy

Our aim was to investigate whether dynamic contrast-enhanced ultrasound (DCE-US) can detect early changes in perfusion of colorectal liver metastases after initiation of chemotherapy. Newly diagnosed patients with colorectal cancer with liver metastases were enrolled in this explorative prospective study. Patients were treated with capecitabine or 5-fluorouracil-based chemotherapy with or without bevacizumab. DCE-US was performed before therapy (baseline) and again 10 days after initiation of treatment. Change in contrast-enhancement in one liver metastasis (indicator lesion) was measured. Treatment response was evaluated with a computed tomography (CT) scan after three cycles of treatment and the initially observed DCE-US change of the indicator lesion was related to the observed CT response. Eighteen patients were included. Six did not complete three series of chemotherapy and the evaluation CT scan, leaving twelve patients for analysis. Early changes in perfusion parameters using DCE-US did not correlate well with subsequent CT changes. A subgroup analysis of eight patients receiving bevacizumab, however, demonstrated a statistically significant correlation (p = 0.045) between early changes in perfusion measures of peak enhancement at DCE-US and tumor shrinkage at CT scan. The study indicates that early changes in DCE-US perfusion measures may predict subsequent treatment response of colorectal liver metastases in patients receiving bevacizumab.

Unusual tumour ablations: report of difficult and interesting cases

Image-guided ablations are nowadays applied in the treatment of a wide group of diseases and in different organs and regions, and every day interventional radiologists have to face more difficult and unusual cases of tumour ablation. In the present case review, we report four difficult and unusual cases, reporting some tips and tricks for a successful image-guided treatment.

Microwave ablation in primary and secondary liver tumours: technical and clinical approaches

Thermal ablation is increasingly being utilised in the treatment of primary and metastatic liver tumours, both as curative therapy and as a bridge to transplantation. Recent advances in high-powered microwave ablation systems have allowed physicians to realise the theoretical heating advantages of microwave energy compared to other ablation modalities. As a result there is a growing body of literature detailing the effects of microwave energy on tissue heating, as well as its effect on clinical outcomes. This article will discuss the relevant physics, review current clinical outcomes and then describe the current techniques used to optimise patient care when using microwave ablation systems.

Image-guided thermal ablation of benign thyroid nodules

Benign thyroid nodules are a common disease in the general population. Most often, they are completely asymptomatic and discovered occasionally during routine ultrasound examinations, and do not require any treatment. When thyroid nodules become symptomatic, surgical excision is still considered standard treatment. In the last few years, several experiences in the treatment of benign thyroid nodules through image-guided percutaneous thermal ablation have been reported with encouraging results, so that currently, these treatments are often proposed as first-choice options for patients with symptomatic benign thyroid nodules. In this paper, we discuss the present literature on the topic, focusing on different techniques available for image-guided percutaneous ablation, particularly radiofrequency (RFA), laser (LA), microwave (MWA), and high-intensity-focus ultrasound (HIFU). Little evidence about the efficacy of MWA and HIFU is now available. According to the literature, good results have been obtained with RFA and LA. Regarding RFA, volume reduction after ablative treatment has been found to range from 47 to 84 % at 3-6 months, and from 62 to 93 % at 1 year; LA also seems to be effective in achieving shrinkage of thyroid nodules, with volume reduction from 37 to 81 % at 3-6 months, and from 13 to 82 % at 1-year follow-up. Moreover, applications of advanced image-guidance modality, such as contrast-enhanced ultrasound and virtual navigation with fusion imaging, are discussed.

Role of contrast-enhanced ultrasonography with Sonazoid for hepatocellular carcinoma: evidence from a 10-year experience

Hepatocellular carcinoma (HCC) represents primary liver cancer. Because the development of HCC limits the prognosis as well as the quality of life of the patients, its management should be properly conducted based on an accurate diagnosis. The liver is the major target organ of ultrasound (US), which is the simple, non-invasive, and real-time imaging method available worldwide. Microbubble-based contrast agents are safe and reliable and have become popular, which has resulted in the improvement of diagnostic performances of US due to the increased detectability of the peripheral blood flow. Sonazoid (GE Healthcare, Waukesha, WI, USA), a second-generation contrast agent, shows the unique property of accumulation in the liver and spleen. Contrast-enhanced US with Sonazoid is now one of the most frequently used modalities in the practical management of liver tumors, including the detection and characterization of the nodule, evaluation of the effects of non-surgical treatment, intraoperative support, and post-treatment surveillance. This article reviews the 10-year evidence for contrast-enhanced US with Sonazoid in the practical management of HCC.