The Role of Contrast-Enhanced Ultrasound in Guiding Radiofrequency Ablation of Hepatocellular Carcinoma

Occult liver nodules: their detection and characterization with CEUS

OBJECTIVES

Contrast enhanced ultrasound (CEUS) now joins the ranks of CT and MRI for noninvasive diagnosis of hepatocellular carcinoma (HCC). CEUS LI-RADS provides greater than 95% specificity for diagnosis within LR-5. Unlike CT/MRI, CEUS is nodule based. Currently, LI-RADS does not recommend CEUS of nodules occult or invisible on pre-contrast ultrasound except by experts. This study addresses our ability to find occult nodules using CEUS and to characterize them with CEUS LI-RADS.

METHODS

100 patients at risk for HCC, 81 with cirrhosis, with occult lesions were retrospectively identified from our archived patient logs. All patients had CEUS examination. Three specialized CEUS techniques (blindshot injection, portal venous (PVP) sweep of the liver, and on-top injection) are used to evaluate nodules.

RESULTS

There were 114 occult lesions in 100 patients. The origin of 78(68%) lesions was an MRI (n = 69) or CT scan (n = 9) with an observation of abnormal enhancement, generally arterial phase hyperenhancement (APHE). All these patients had blindshot CEUS injection looking for a correlate with APHE. The remainder of occult lesions (n = 36)(32%) were first detected during CEUS, generally as washout foci on PVP sweeps or incidental APHE or washout nearby other targets. All washout areas had subsequent on-top injection to assess for APHE. Application of CEUS LI-RADS algorithm categorized 26 LR-5, 34 LR-4, and 5 LR-M. CEUS upgraded LI-RADS category of 24/50(48%) occult lesions reported on CT/MRI. 29(25%) occult lesions were offered treatment and from categories LR-5 and LR-M, 5 had biopsy confirmation and 15 were treated. From both sources, MR/CT and CEUS, there were 12 occult lesions scanned for treatment response, categorized as 7 LR-TR viable, 1 LR-TR nonviable, and 4 LR-TR equivocal on CEUS.

CONCLUSION

Our study shows we can find and characterize occult nodules using CEUS techniques and CEUS LI-RADS algorithm, with positive impact on clinical management.

Role of contrast-enhanced ultrasound with Perfluorobutane in lesion detection, guidance for microwave ablation, and response assessment of hepatocellular carcinoma

PURPOSE

To evaluate role of perfluorobutane in guiding microwave ablation of HCC and to compare treatment response at 3 h of ablation using contrast-enhanced US (CEUS) with Sonazoid with 1-month follow-up contrast-enhanced CT/MRI.

METHODS

This was a single center prospective study and consecutive patients planned for microwave ablation of HCC from October to November 2021 were enrolled. Pre-procedure CEUS were performed using Sonazoid in both vascular and Kupffer phase and number of Kupffer defects compared with gray scale US. Precise needle placement of microwave applicator was done in the Kupffer phase. 3 hours post ablation CEUS was repeated to evaluate response assessment using Liver Imaging Reporting and Data System Treatment Response criteria (LR TR). One-month follow-up imaging was done using multiphasic CECT/dynamic CEMRI and comparison was done with post procedure CEUS.Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 5 Given name: [Manoj Kumar] Last name [Sharma]. Author 6 Given name: [Shiv Kumar] Last name [Sarin]. Also, kindly confirm the details in the metadata are correct. all the names and affiliations are correct RESULTS: A total of 26 patients (24 males and 2 females, mean age 61.38 ± 9.76 years) having 40 lesions, of mean tumor diameter 21.4 ± 7.7 mm, underwent CEUS and ablation. Most common etiology for cirrhosis was viral hepatitis, followed by non-alcoholic steatohepatitis (NASH). Four (10%) additional lesions (which were seen on pre-procedure imaging) were detected in Kupffer phase over gray scale US. All lesions showed complete response in the immediate post procedure CEUS. Technique efficacy at 1-month was 95% according to the LR TR criteria.Please check the edit made in article title and amend if necessary.The edit is correct and appropriatePlease check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary.All the names and their respective affiliations are correct CONCLUSION: CEUS with Sonazoid is an excellent modality for precise needle placement for ablation due to stable nature and excellent lesion visibility of Kupffer phase.

Usefulness of ultrasound fusion technology for hepatocellular carcinoma localisation, pre- and post-thermal ablation

INTRODUCTION

Percutaneous thermal ablation of inconspicuous lesions can be challenging. Fusion ultrasound (FUS) allows the use of previously performed diagnostic imaging like computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET-CT) to localise hepatocellular carcinoma (HCC) for treatment. This paper illustrates FUS case studies of pre-, intra- and post-ablation imaging of inconspicuous HCC, supplemented by use of contrast-enhanced ultrasound (CEUS).

METHOD

Four prospective cases during September 2014 to October 2018, with HCC amenable to ablation, which were poorly identified on ultrasound, underwent FUS. FUS pre-screening was scheduled within three months of the previous CT or MRI, and between one to four weeks prior to the scheduled ablation date. Post-ablation imaging with FUS was performed between four to six weeks to coincide with their routine follow-up CT or MRI.

FINDINGS

There were potential benefits observed in the cases with combined techniques of FUS and CEUS for limiting circumstances such as heat sink effect, multiple lesions targeting, inconspicuous lesion detection and pre-ablation technical feasibility assessment.

DISCUSSION

The combined use of FUS and CEUS improves tumour visibility, increases operator imaging confidence and reduces heat sink effect during percutaneous thermal ablation.

CONCLUSION

FUS imaging is helpful in targeting poor conspicuity lesions that cannot be detected on grey-scale ultrasound. It facilitates in ensuring optimal treatment of hepatic lesions for improvement of patient prognosis and follow-up imaging.

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 guidance in core-needle biopsy for diagnosis of cervical tuberculous lymphadenitis

OBJECTIVE

To investigate the diagnostic value of core-needle biopsy (CNB) guided by contrast-enhanced ultrasound (CEUS) in cervical tuberculous lymphadenitis (CTL).

METHODS

178 patients with pathological confirmation of CTL were retrospectively enrolled. All of them had undergone CNB prior to the final surgery. According to the different ways of puncture guidance, they were divided into two groups: conventional ultrasound (US) group (n = 81) and CEUS group (n = 97). The comparison of diagnostic efficacy between two groups was compared and analyzed.

RESULTS

Among the 178 patients, 146 were directly diagnosed as CTL by CNB, including 59 patients in CEUS group and 87 patients in US group. The diagnostic accuracy were 89.7% (87/97) and 72.8% (59/81), respectively (P < 0.01). For subgroup analyses, differences among diagnostic efficacy ascribed to the different guiding methods were significant in medium size group (>2.0 cm and ≤3.0 cm) and large size group (>3.0 cm), 91.7% for CEUS group vs. 69.0% for US group (P < 0.05) and 84.4% for CEUS group vs. 57.7% for US group (P < 0.05), respectively.

CONCLUSIONS

In the diagnosis of CTL, compared with the US-guided CNB, CEUS-guided CNB have certain advantages, especially for larger lymph nodes.

Diagnostic yield of Xpert MTB/RIF on contrast-enhanced ultrasound-guided pleural biopsy specimens for pleural tuberculosis

BACKGROUND

A 3-year prospective study was conducted to evaluate the efficacy of Xpert MTB/RIF (Xpert) in the diagnosis of pleural tuberculosis (pTB) on contrast -enhanced ultrasound (CEUS)-guided pleural biopsy specimens.

METHOD

Patients suspected with pTB were prospectively enrolled to receive CEUS-guided biopsy. Specimens (pleural tissue and fluid) were submitted for Xpert and other routine examinations. Surgical thoracoscopy was performed on undiagnosed cases.

RESULT

A total of 316 patients were enrolled, including 280 cases of pTB (definite 195, possible 85) and 36 cases of non-pTB. The sensitivity of Xpert was 69.64% (195/280) in biopsy specimens, which was significantly higher than that in pleural effusion specimens (p < 0.01). In 195 definite cases, the highest sensitivity of 100% (195/195) and NPV of 29.75% (36/121) were achieved by Xpert on biopsy specimens. Xpert-positive results were obtained in 149 culture-negative cases and 90 histopathological MTB PCR-negative cases. The incidence of necrosis by CEUS in Xpert-positive pTB was significantly higher than that in Xpert-negative pTB (χ² = 72.41; p < 0.01). No serious complications occurred.

CONCLUSION

Xpert achieved highly diagnostic sensitivity in pTB through CEUS-guided biopsy sampling, especially on necrotic lesions, which was proven to be efficient, minimally invasive and safe.

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.

Guidelines and Good Clinical Practice Recommendations for Contrast Enhanced Ultrasound (CEUS) in the Liver - Update 2020 - WFUMB in Cooperation with EFSUMB, AFSUMB, AIUM, and FLAUS

The present, updated document describes the fourth iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS), first initiated in 2004 by the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB). The previous updated editions of the guidelines reflected changes in the available contrast agents and updated the guidelines not only for hepatic but also for non-hepatic applications.The 2012 guideline requires updating as previously the differences of the contrast agents were not precisely described and the differences in contrast phases as well as handling were not clearly indicated. In addition, more evidence has been published for all contrast agents. The update also reflects the most recent developments in contrast agents, including the United States Food and Drug Administration (FDA) approval as well as the extensive Asian experience, to produce a truly international perspective.These guidelines and recommendations provide general advice on the use of ultrasound contrast agents (UCA) and are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis to improve the management of patients.

Guidelines and Good Clinical Practice Recommendations for Contrast-Enhanced Ultrasound (CEUS) in the Liver-Update 2020 WFUMB in Cooperation with EFSUMB, AFSUMB, AIUM, and FLAUS

The present, updated document describes the fourth iteration of recommendations for the hepatic use of contrast-enhanced ultrasound, first initiated in 2004 by the European Federation of Societies for Ultrasound in Medicine and Biology. The previous updated editions of the guidelines reflected changes in the available contrast agents and updated the guidelines not only for hepatic but also for non-hepatic applications. The 2012 guideline requires updating as, previously, the differences in the contrast agents were not precisely described and the differences in contrast phases as well as handling were not clearly indicated. In addition, more evidence has been published for all contrast agents. The update also reflects the most recent developments in contrast agents, including U.S. Food and Drug Administration approval and the extensive Asian experience, to produce a truly international perspective. These guidelines and recommendations provide general advice on the use of ultrasound contrast agents (UCAs) and are intended to create standard protocols for the use and administration of UCAs in liver applications on an international basis to improve the management of patients.

The Application Comparison of Contrast-Enhanced Ultrasound and Contrast-Enhanced Computed Tomography in Radiofrequency Ablation Treatment for Hepatocellular Carcinoma

Objective: To compare the application value of contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT) in radiofrequency ablation (RFA) for treatment of hepatocellular carcinoma (HCC). Methods: A total of 112 patients with primary HCC were enrolled for the treatment of RFA and they were randomly equally divided into the CEUS group and CECT group. The gender, age, and number and maximum diameter of tumors between the two groups were compared. The median duration of follow-up was 27.0 months and the clinical outcomes were compared. Results: The average examination time period before ablation, of guiding needle insertion and of ablation in the CEUS group were significantly shorter than those in the CECT group (p < 0.05). The complete ablation rate of the CEUS group was significantly higher than that of the CECT group (86.36% vs. 73.17%, χ² = 4.618, p = 0.032). There was no comparative difference in the incidence of complications (including fever, infection, pain, and liver injury) between the two groups (p > 0.05). The relapse rate of the CEUS group was lower and the survival rate was higher than that in the CECT group (p < 0.05). Conclusions: Compared with the CECT, the RFA for treatment of HCC guided by the CEUS shorten the time of examination and treatment. The immediate postoperative assessment can improve the overall complete ablation rate, reduce the relapse rate, and increase the survival rate, which provides insights for the clinical application.

Resection vs. ablation for lesions characterized as resectable-ablative within the colorectal liver oligometastases criteria: a propensity score matching from retrospective study

Background

There has been no prospective or retrospective studies reporting the comparison outcome between surgery and ablation for resectable-ablative (lesions could be treated by resection or complete ablation) colorectal liver oligometastases (CLOM). The purpose of this study was to compare the efficacy and prognostic difference in patients who underwent R0 resection vs. complete ablation within the resectable-ablative CLOM criteria.

Methods

From January 2008 to May 2018, a total of 2,367 patients diagnosed with colorectal liver metastases were included in this observational study. The metastasis was characterized by only limited to liver with number ≤5, size ≤5 cm, and resectable-ablative (lesions could be treated by resection or complete ablation). The evaluated indications, including liver progression-free survival (LPFS), overall survival (OS), survival rates, pattern and number of recurrences, and complications, were compared by using propensity score matching (PSM). The Kaplan-Meier curves were generated, and a log-rank test was performed. The Cox regression model was used for univariate and multivariate analyses to identify predictors of outcomes.

Results

A total of 421 consecutive patients were eligible for this study, with 250 and 171 undergoing R0 resection and complete ablation, respectively. PSM identified 145 patients from each group. The 1-, 3-, 5- and 8-year OS rates in the resection group and the ablation group were 95.8% vs. 95.0%, 69.8% vs. 60.1%, 53.6% vs. 42.5%, and 45.1% vs. 32.9% (p = 0.075), respectively. The median LPFS in the resection group was significantly longer than that in the ablation group (35 months vs. 15 months, p = 0.011). No statistical difference was found in LPFS between the two groups when comparing ≤3 cm liver metastases. For liver metastasis >3 cm, the median LPFS in the resection group and ablation group was 11 months and 5 months, respectively (p = 0.001). In terms of high risk of clinical risk score (CRS), the resection group showed longer LPFS than the ablation group (median 18 months vs. 10 months, p = 0.043).

Conclusion

For patients within the CLOM criteria suggesting that liver metastases were resectable as well as ablative, resection could result in longer liver recurrence-free survival than ablation in cases with size >3 cm or high risk of CRS. But for ≤3 cm liver metastases, their treatment efficacies were comparable.

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 US in Local Ablative Therapy and Secondary Surveillance for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) has a high incidence of recurrence following therapy. Therefore, secondary surveillance (scheduled follow-up imaging after treatment) is an important part of disease management. The recent approval in the United States for use of a microbubble-based contrast agent for US liver imaging promotes the increased use of contrast-enhanced US (CEUS) in patients with HCC. Although the criteria for the diagnosis of HCC at CEUS are well described, there is a paucity of published literature describing the role of CEUS in ablative therapy and secondary surveillance. In the setting of ablative therapy, CEUS can have vital roles, including patient selection, intraprocedural guidance, and immediate postprocedural assessment. Although CEUS is not widely used, the authors found that it can be used to accurately detect residual or recurrent tumor, characterize the geographic pattern of recurrence (intrazonal, extrazonal, segmental, or remote), and assess for tumor in vein. In addition, similar to primary surveillance, secondary surveillance includes assessment of the entire liver for evaluation of new nodules. Arterial phase hyperenhancement is the reference standard characteristic of disease recurrence at secondary surveillance with CEUS. ^©RSNA, 2019 See discussion on this article by Rodgers.

Use of Ultrasound Contrast Agents in Relation to Percutaneous Interventional Procedures: A Systematic Review and Pictorial Essay

The aim of this article is to provide an inventory of the use of contrast-enhanced ultrasound (CEUS) in relation to percutaneous interventional procedures. The article is structured into a systematic literature review followed by a clinical part relating to percutaneous CEUS-guided procedures. A literature search identified 3109 records. After abstract screening, 55 articles were analyzed and supplemented with pictorial material to explain the techniques. In conclusion, the best-evidenced indications for CEUS-guided interventions are biopsy and ablation of inconspicuous or B-mode-invisible tumors, intraprocedural ablation control and follow-up, as well as percutaneous transhepatic cholangiography and drainage procedures.

Treatment of hepatocellular carcinoma in the caudate lobe: US-guided percutaneous radiofrequency ablation combined with ethanol ablation

AIM

To evaluate the technical feasibility and treatment results of ultrasound (US)-guided percutaneous radiofrequency ablation (RFA) combined with ethanol ablation (EA) for hepatocellular carcinoma (HCC) in the caudate lobe.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and the requirement for informed consent was waived. From October 2009 to June 2016, there were 49 patients with HCC in the caudate lobe underwent ablation. Among them, 14 patients (12 men and two women, mean age: 49.9±14.9 years) with 16 caudate lobe HCCs (mean size: 3±1.1 cm) who underwent US-guided RFA-EA were identified. These patients were compared with patients who underwent RFA alone (n=17) and EA alone (n=18).

RESULTS

HCCs in the RFA-EA group were larger than those in the EA-alone group (3±1.1 versus 2.1±0.7 cm, p=0.028). In the RFA-EA group, all the patients achieved treatment success (14/14) and entered follow-up. After a follow-up period of 17.1±10.6 months (range, 5-36 months), local tumour progression (LTP) was detected in four tumours. The 1- and 2-year LTP rates after RFA-EA were 18.8% and 27.8%, respectively. The 1- and 2-year disease-free survival (DFS) rates were 35.7% and 13.4%. Six patients died, with the 1-, 2-, and 3-year overall survival (OS) rates of 85.1%, 63.1%, and 21%, respectively. There were no significant differences in the LTP, DFS, and OS rates between the RFA-EA group and RFA-alone or EA groups (p=0.363-0.733).

CONCLUSION

US-guided percutaneous RFA-EA appears to be a feasible and effective treatment for HCC in the caudate lobe.

Contrast-Enhanced Ultrasound of the Liver: Optimizing Technique and Clinical Applications

OBJECTIVE

The purpose of this article is to review the general principles, technique, and clinical applications of contrast-enhanced ultrasound of the liver.

CONCLUSION

Proper technique and optimization of contrast-enhanced ultrasound require a balance between maintaining the integrity of the microbubble contrast agent and preserving the ultrasound signal. Established and emerging applications in the liver include diagnosis of focal lesions, aiding ultrasound-guided intervention, monitoring of therapy, and aiding surgical management.

Ultrasound-guided transcervical radiofrequency ablation for symptomatic uterine adenomyosis

OBJECTIVE

To retrospectively evaluate the midterm outcomes of transvaginal ultrasound-guided radiofrequency ablation (RFA) for the treatment of symptomatic uterine adenomyosis.

METHODS

87 patients with symptomatic uterine adenomyosis, who met the inclusion criteria, were enrolled in our study from January 2013 to October 2015. All of the patients underwent transvaginal ultrasound-guided RFA and were followed up for 12 months. Assessment end points included uterus volume reduction rate, lesion regression rate, dysmenorrhoeal score, symptom severity score (SSS) and adverse events.

RESULTS

In all 87 patients, 81 patients fulfilled the follow-up evaluations post-ablation. The mean uterine volume reduction rate was 35.8% at 1 month, 40.8% at 6 months and 41.2% at 12 months post-ablation. Dysmenorrhoea and SSS statistically significantly declined. Reintervention rate was 18.5%. Two patients developed intrauterine adhesion after ablation. No serious complications including penetration or burn injuries of the nearby organs were observed.

CONCLUSION

Ultrasound-guided RFA might be a safe and effective minimally invasive alternative in the treatment of symptomatic adenomyosis. Advances in knowledge: This is the first study to evaluate the efficacy and safety of ultrasound-guided RFA for the treatment of adenomyosis to our knowledge. This is also the first study to provide various changes of intrauterine cavity after this treatment.

Radiofrequency Ablation Guided by Contrast-Enhanced Sonography versus B-Mode Sonography for Hepatocellular Carcinoma after Transcatheter Arterial Chemoembolization

PURPOSE

Contrast-enhanced sonography increases negative enhancement in the Kupffer phase after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). We compared contrast-enhanced sonography with B-mode sonography for guidance of radiofrequency ablation (RFA) of HCC after TACE.

METHODS

After TACE was performed, 18 nodules in 12 patients were treated by B-mode sonography guided RFA, while 22 nodules in 18 patients were treated by contrast-enhanced sonography-guided RFA.

RESULTS

The success rate of initial RFA was 83.3% (15/18 nodules) in the B-mode sonography group. On the other hand, the success rate was 100% (22/22 nodules) in the contrast-enhanced sonography group and the difference was significant (p = 0.046).

CONCLUSION

These findings suggest that RFA guided by Kupffer phase contrast-enhanced sonography after TACE is a promising therapeutic option for curing HCC.

Efficacy and safety of radiofrequency ablation and transcatheter arterial chemoembolization for treatment of hepatocellular carcinoma: A meta-analysis

AIM

To investigate the efficacy and safety of radiofrequency ablation (RFA) and transcatheter arterial chemoembolization (TACE) for treatment of patients with hepatocellular carcinoma (HCC).

METHODS

All eligible studies were collected from PubMed, the Cochrane Libraries and Embase. The evaluation indices included overall survival (OS) rate, recurrence-free survival rate, local tumor progression rate and major complications. All statistical analysis was performed by RevMan version 5.2 software.

RESULTS

There were 21 studies with 3073 patients included in this meta-analysis. The RFA monotherapy was associated with higher 3- and 5-year OS rates (OR3-year  = 2.33, 95% confidence interval [CI] = 1.34-4.05; OR5-year  = 2.05, 95% CI = 1.48-2.85) compared with TACE alone. The combination of RFA and TACE was associated with higher 1-, 3- and 5-year OS rates (OR1-year  = 1.94, 95% CI = 1.28-2.96; OR3-year  = 1.56, 95% CI = 1.19-2.04; OR5-year  = 1.53, 95% CI = 1.13-2.07) compared with RFA alone.

CONCLUSION

The combination of TACE with RFA could obviously improve the short- and long-term survival rates and significantly provide a better prognosis for patients with intermediate-size HCC. RFA was associated with a higher long-term OS rate than that of TACE-treated patients with HCC.