Focal Liver Lesions Research Articles

Comparative Analysis of Contrast-Enhanced Ultrasound and Computed Tomography in the Differential Diagnosis of Focal Liver Lesions in Patients with a History of Advanced Cancer

Цель. Проанализировать диагностическую эффективность мультипараметрического ультразвукового исследования с контрастным усилением в дифференциальной диагностике очаговых образований печени у онкопациентов и сравнить полученные данные с компьютерной томографией и гистологическим заключением.
 Материалы и методы. Проведён ретроспективный анализ результатов исследований 123 пациентов с очаговыми изменения печени, из них 96 женщин (средний возраст 56,1 ±13,6) и 27 мужчин (средний возраст 55,0±14,0). Всем пациентам проводилось мультипараметрическое ультразвуковое исследование и компьютерная томография с контрастированием. При подозрении на злокачественный процесс выполнялась трепан-биопсия печени под ультразвуковым наведением. В случае выявления признаков, характерных для доброкачественных образований, пациент находился на динамическом контроле каждые 3 месяца в первый год наблюдения, отсутствие динамики через 6-12 месяцев свидетельствовало в пользу доброкачественного процесса. При увеличении размеров образования также выполнялась морфологическая верификация.
 Результаты. Результаты для серошкального режима составили: чуствительность (Ч)-58,1%, специфичность (С)-68,4%, точность (Т)-60,2%, прогностическая ценность положительного результата (ПЦПР)- 87,8%, прогностическая ценность отрицательного результата (ПЦОР)-29,5%. Эффективность контрастно-усиленного ультразвукового исследования (КУУЗИ) значимо превышала исследование в традиционном серошкальном режиме и составила: Ч-90,5%, С-84,2%, Т-89,2%, ПЦПР-95,7%, ПЦОР-69,6%. Для компьютерной томографии с контрастным усилением (КТ с КУ) результаты были сопоставимы с КУУЗИ и составили: Ч-83,6%, С-78,9%, Т-82,6%, ПЦПР-93,8%, ПЦОР-55,6%.
 Полученные нами значения подтверждают высокую информативность КУУЗИ в оценке очагового поражения печени, в связи с чем в ряде случаев (отсутствие технической возможности проведения или наличие противопоказаний к КТ с КУ, а также полученные неоднозначные результаты по другим методика) может выступить в качестве метода выбора.
 Заключение. Мультимодальная диагностика превосходит единый метод визуализации по чувствительности скрининга и точности диагностики. КТ с КУ и КУУЗИ дополняют друг друга при дифференциальной диагностике очагов в печени неясного генеза. Использование КТ с КУ в сочетании с КУУЗИ показывает клиническую ценность для пациентов, что особенно важно у лиц с отягощённым онкоанамнезом.

MR Fingerprinting for Contrast Agent-free and Quantitative Characterization of Focal Liver Lesions.

Purpose To evaluate the feasibility of liver MR fingerprinting (MRF) for quantitative characterization and diagnosis of focal liver lesions. Materials and Methods This single-site, prospective study included 89 participants (mean age, 62 years ± 15 [SD]; 45 women, 44 men) with various focal liver lesions who underwent MRI between October 2021 and August 2022. The participants underwent routine clinical MRI, non-contrast-enhanced liver MRF, and reference quantitative MRI with a 1.5-T MRI scanner. The bias and repeatability of the MRF measurements were assessed using linear regression, Bland-Altman plots, and coefficients of variation. The diagnostic capability of MRF-derived T1, T2, T2*, proton density fat fraction (PDFF), and a combination of these metrics to distinguish benign from malignant lesions was analyzed according to the area under the receiver operating characteristic curve (AUC). Results Liver MRF measurements showed moderate to high agreement with reference measurements (intraclass correlation = 0.94, 0.77, 0.45, and 0.61 for T1, T2, T2*, and PDFF, respectively), with underestimation of T2 values (mean bias in lesion = -0.5%, -29%, 5.8%, and -8.2% for T1, T2, T2*, and PDFF, respectively). The median coefficients of variation for repeatability of T1, T2, and T2* values were 2.5% (IQR, 3.6%), 3.1% (IQR, 5.6%), and 6.6% (IQR, 13.9%), respectively. After considering multicollinearity, a combination of MRF measurements showed a high diagnostic performance in differentiating benign from malignant lesions (AUC = 0.92 [95% CI: 0.86, 0.98]). Conclusion Liver MRF enabled the quantitative characterization of various focal liver lesions in a single breath-hold acquisition. Keywords: MR Imaging, Abdomen/GI, Liver, Imaging Sequences, Technical Aspects, Tissue Characterization, Technology Assessment, Diagnosis, Liver Lesions, MR Fingerprinting, Quantitative Characterization Supplemental material is available for this article. © RSNA, 2023.

Characterization of solid liver focal lesions by CEUS: monocentric Italian experience

Characterization of solid liver focal lesions by CEUS: monocentric Italian experience

Comments and illustrations of the WFUMB CEUS liver guidelines: Cystic fibrosis associated liver disease.

In this series of articles with comments and illustrations on the World Federation for Medicine and Biology (WFUMB) guidelines on contrast-enhanced ultrasound (CEUS) the topics of very rare focal liver lesions (FLL) are discussed. Improving the detection and characterization of the most common FLL are the main topics of these guidelines. The focus of this review is on the many manifestations of cystic fibrosis-related liver disease (CFLD). These include focal biliary fibrosis, liver cirrhosis, vascular manifestations with nodular regenerative hyperplasia and portal hypertension with or without cirrhosis. This article describes the diverse changes of liver involvement in cystic fibrosis and their appearance on ultrasound, duplex sonography, and contrast enhanced ultrasonography. This knowledge and the imaging should help to recognize liver manifestations in time and enable a correct interpretation of ultrasound images in CF in the corresponding clinical situation.

Clinical and Radiological Parameters to Discriminate Tuberculous Peritonitis and Peritoneal Carcinomatosis.

It is challenging to differentiate between tuberculous peritonitis and peritoneal carcinomatosis due to their insidious nature and intersecting symptoms. Computed tomography (CT) is the modality of choice in evaluating diffuse peritoneal disease. We conducted an ambispective analysis of patients suspected as having tuberculous peritonitis or peritoneal tuberculosis between Jan 2020 to Dec 2021. The study aimed to identify the clinical and radiological features differentiating the two entities. We included 44 cases of tuberculous peritonitis and 45 cases of peritoneal carcinomatosis, with a median age of 31.5 (23.5-40) and 52 (46-61) years, respectively (p ≤ 0.001). Fever, past history of tuberculosis, and loss of weight were significantly associated with tuberculous peritonitis (p ≤ 0.001, p = 0.038 and p = 0.001). Pain in the abdomen and history of malignancy were significantly associated with peritoneal carcinomatosis (p = 0.038 and p ≤ 0.001). Ascites was the most common radiological finding. Loculated ascites, splenomegaly and conglomeration of lymph nodes predicted tuberculous peritonitis significantly (p ≤ 0.001, p = 0.010, p = 0.038). Focal liver lesion(s) and nodular omental involvement were significantly associated with peritoneal carcinomatosis (p = 0.011, p = 0.029). The use of clinical features in conjunction with radiological findings provide better diagnostic yields because of overlapping imaging findings.

Blebbing of the plasma membrane of lymphocytes as a marker of endothelial dysfunction in the development of post-resection insufficiency in patients with focal liver lesions

Purpose of the study. To evaluate the intensity of blebbing of the plasma membrane of lymphocytes and the formation of microparticles of lymphocytic origin in patients with postresection hepatic failure. Material and methods. The study involved 54 patients with focal liver diseases. The study involved 32 (59%) women, 22 (41%) men. The average age was 59.5 [49.75; 66,00]. Patients were divided into groups, 1 group - 10 patients with developed acute liver failure and 2 group - 44 patients with a favorable course of postoperative period. The following surgical interventions were performed: 36 (67%) patients underwent surgery - laparotomy, segmental liver resection, 10 (18%) - left-sided hemihepatectomy and 8 (15%) - right-sided hemihepatectomy. Results. Predictors of early postoperative hepatic failure are a decrease in initial blebbing and an increase in terminal blebbing and free microparticles of lymphocytic origin. Conclusions. Thus, changes in lymphocyte blebbing and the presence of free microparticles of lymphocytic origin are due to the development of endothelial insufficiency and apoptosis of lymphocytes in the context of liver failure and are determined by the reduced function of residual liver volume.

Contrast-enhanced ultrasound (CEUS) for characterisation of focal liver lesions

Due to the trend towards increased use of imaging and rising awareness among high-risk patients, gastroenterologists and hepatologists are more frequently confronted with patients with focal liver lesions. In the differentiation of these lesions, CT and MRI have increasingly found their way into primary diagnostic steps in everyday clinical practice. Contrast-enhanced sonography, on the other hand, is a very effective and cost-efficient method for assessing focal liver lesions. The success of the method is not only based on the visualisation of microvascularisation in real time. If sonography is performed by the treating physician, he can use the exact knowledge of history and clinical findings to specifically adapt the examination procedure and to interpret the sonographic findings with greater accuracy ("clinical sonography"). At the same time, the method enables the practitioner to combine diagnostics and management decisions in his or her own hands. To achieve excellent results with contrast-enhanced sonography-as with any other imaging method-it is necessary that the examiner is sufficiently qualified.This article systematically presents the sonographic characteristics of the most common liver lesions and clearly shows their contrast patterns using videos (available via QR code). The article illustrates that CEUS could-and from the authors' point of view, should-have an even greater significance in the future.

Comments and illustrations of the WFUMB CEUS liver guidelines: Peliosis hepatis and porphyria.

In this series of articles on comments and illustrations of the World Federation for Medicine and Biology (WFUMB) guidelines on contrast-enhanced ultrasound (CEUS), the topics on very rare focal liver lesions (FLL) are discussed. This article describes the diverse changes of focal liver lesions in peliosis hepatis and the typical changes in porphyria. Although the focus is on the appearance on ultrasound and CEUS, the clinical context is always considered. While peliosis may be a surprising finding on puncture, lesions in porphyria cutanea tarda may be typical visual diagnoses that obviate the need for biopsy. If only you knew. This article aims to sharpen the clinician's eye. It provides knowledge of the clinical presentation and US and CEUS imaging of peliosis hepatis and porphyria.

Comments and illustrations of the WFUMB CEUS liver guidelines: Rare focal liver lesions - infectious (bacterial).

In this series of papers on comments and illustrations of the World Federation for Medicine and Biology (WFUMB) guidelines on contrast enhanced ultrasound (CEUS) the topics of bacterial infections are discussed. Improved detection and characterization of common focal liver lesions (FLL) are the main topics of these guidelines but detailed and illustrating information is missing. The focus in this paper on infectious (bacterial) focal liver lesions is on their appearance on B-mode and Doppler ultrasound and CEUS features. Knowledge of these data should help to raise awareness of these rarer findings, to think of these clinical pictures in the corresponding clinical situation, to interpret the ultrasound images correctly and thus to initiate the appropriate diagnostic and therapeutic steps in time.

CT-Guided Liver Biopsy: Evaluation of Spectral Data From Dual-Layer Detector CT for Improved Lesion Detection

PurposeEvaluation of dual-layer spectral computed tomography (CT) for contrast enhancement during image-guided biopsy of liver lesions using virtual monoenergetic images (VMI) and virtual non-contrast (VNC) images.MethodsSpectral CT data of 20 patients receiving CT-guided needle biopsy of focal liver lesions were used to generate VMI at energy levels from 40 to 200 keV and VNC images. Images were analyzed objectively regarding contrast-to-noise ratio between lesion center (CNRcent) or periphery (CNRperi) and normal liver parenchyma. Lesion visibility and image quality were evaluated on a 4-point Likert scale by two radiologists.ResultsUsing VMI/VNC images, readers reported an increased visibility of the lesion compared to the conventional CT images in 18/20 cases. In 75% of cases, the highest visibility was derived by VMI-40. Showing all reconstructions simultaneously, VMI-40 offered the highest visibility in 75% of cases, followed by VNC in 12.5% of cases. Either CNRcent (17/20) or/and CNRperi (17/20) was higher (CNR increase > 50%) in 19/20 cases for VMI-40 or VNC images compared to conventional CT images. VMI-40 showed the highest CNRcent in 14 cases and the highest CNRperi in 12 cases. High image quality was present for all reconstructions with a minimum median of 3.5 for VMI-40 and VMI-50.ConclusionsWhen implemented in the CT scanner software, automated contrast enhancement of liver lesions during image-guided biopsy may facilitate the procedure.Graphical

Washout appearance of hepatocellular carcinomas using standardized contrast-enhanced ultrasound (CEUS) including an extended late phase observation - Real-world data from the prospective multicentre DEGUM study.

Non-invasive diagnosis of hepatocellular carcinoma (HCC) in contrast-enhanced ultrasound (CEUS) is based on the combination of arterial phase hyperenhancement (APHE) and subsequent late (>60 seconds) and mild contrast washout (WO). Whereas APHE is seen in the majority of HCC, wash-out pattern may vary in onset and intensity. In some HCC lesions, even no washout is seen at all. Our prospective multicentre DEGUM HCC CEUS study aimed at identifying typical and atypical washout appearance of HCC in a real-life setting. High-risked patients for HCC with focal liver lesions upon B-mode ultrasound were recruited prospectively. In a multicentre real-life setting, a standardised CEUS examination including an extended late phase up to 6 minutes was performed. CEUS patterns of HCC were recorded, and onset and intensity of washout appearance were assessed with respect to patient and tumour characteristics. Histological findings served as reference standard. In 230/316 HCC (72.8%), a CEUS pattern of APHE followed by WO was observed. In 158 cases (68.7%), WO was typical (onset > 60 seconds, mild intensity). 72 cases (31.3%) showed marked and / or early WO, whereas in 41 HCCs (13%), APHE was followed by sustained isoenhancement.Atypical WO upon CEUS was associated with macroinvasion of the liver vessels, portal vein thrombosis and diffuse growth pattern, but not tumour size and histological grading. In a prospective multicentre real-life setting, APHE is followed by atypical washout appearance or no washout at all in almost half of the HCCs with APHE. The examiner has to bear in mind that in spite of a characteristic APHE in HCCs, washout appearance can be atypical in CEUS, especially in HCCs with macrovascular invasion or diffuse growth pattern.

Diagnosis of hepatocellular carcinoma using Sonazoid: a comprehensive review.

Sonazoid contrast-enhanced ultrasonography (CEUS) is a promising technique for the detection and diagnosis of focal liver lesions, particularly hepatocellular carcinoma (HCC). Recently, a collaborative effort between the Korean Society of Radiology and Korean Society of Abdominal Radiology resulted in the publication of guidelines for diagnosing HCC using Sonazoid CEUS. These guidelines propose specific criteria for identifying HCC based on the imaging characteristics observed during Sonazoid CEUS. The suggested diagnostic criteria include nonrim arterial phase hyperenhancement, and the presence of late and mild washout, or Kupffer phase washout under the premise that the early or marked washout should not occur during the portal venous phase. These criteria aim to improve the accuracy of HCC diagnosis using Sonazoid CEUS. This review offers a comprehensive overview of Sonazoid CEUS in the context of HCC diagnosis. It covers the fundamental principles of Sonazoid CEUS and its clinical applications, and introduces the recently published guidelines. By providing a summary of this emerging technique, this review contributes to a better understanding of the potential role of Sonazoid CEUS for diagnosing HCC.

Assessment of focal liver lesions in non-cirrhotic liver – expert opinion statement by the Swiss Association for the Study of the Liver and the Swiss Society of Gastroenterology

Focal liver lesions are common, with a prevalence up to 20%. The lesions must be evaluated in context of risk factors associated with malignancy. Risk factors include age >40 years, known current or past malignancy, presence of liver cirrhosis or chronic liver disease (i.e. suspected by elevated liver elastography measurement ≥8 kPa or FIB-4 score ≥1.3), unintentional weight loss, fever or night sweats, newly detected focal liver lesions, documented growth of focal liver lesions, current or past use of androgens (e.g. testosterone, oxymetholone, danazol), increased serum tumour markers (i.e. alpha-fetoprotein, carbohydrate antigen 19-9 [CA19-9], carcinoembryonic antigen [CEA]) and family history of malignancy. In patients without risk factors of malignancy, regional (non-)fatty changes, simple liver cysts and typical haemangiomas can be diagnosed by conventional ultrasound (without contrast). Conventional ultrasound Doppler is recommended to rule out vascular malformations such as portosystemic shunts. In all other cases of focal liver lesions, contrast-enhanced imaging is indicated for differentiation in benign and malignant dignity. Contrast-enhanced ultrasound (CEUS) as a first diagnostic step and contrast-enhanced magnetic resonance imaging (MRI) are accurate tests to diagnose haemangioma and focal nodular hyperplasia. Hepatocellular adenoma is diagnosed by contrast-enhanced MRI and/or histology. “Wash out” on CEUS is highly suspicious for a malignant focal liver lesion. Additional investigations aimed at identifying the primary tumour, as well as staging-computed tomography, MRI and/or histology may be necessary and should be decided on a case-by-case basis. A biopsy of focal liver lesions is indicated in cases of unclear dignity, malignant aspect and focal liver lesions of unclear origin as well as for guiding surgical and oncological management.

Differences between CEUS LI-RADS and CECT LI-RADS in the diagnosis of focal liver lesions in patients at risk for HCC

ObjectivesTo compare the inter-modality consistency and diagnostic performances of the contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) and contrast-enhanced computed tomography (CECT) LI-RADS in patients at risk for hepatocellular carcinoma (HCC), so as to help clinicians to select a more appropriate modality to follow the focal liver lesions (FLLs).MethodsThis retrospective study included untreated 277 FLLs from 247 patients who underwent both CEUS and CECT within 1 month. The ultrasound contrast medium used was SonoVue. FLL categories were independently assigned by two ultrasound physicians and two radiologists using CEUS LI-RADS v2017 and CECT LI-RADS v2018, respectively. The diagnostic performances of CEUS and CECT LI-RADS were evaluated using sensitivity, specificity, positive predictive value (PPV), and negative predictive value. Cohen’s Kappa was employed to evaluate the concordance of the LI-RADS category.ResultsThe inter-modality consistency for CEUS and CECT LI-RADS was 0.31 (p < 0.001). HCC was more frequently observed in CECT LR-3 and LR-4 hepatic lesions than in CEUS (7.3% vs. 19.5%, p < 0.001). The specificity and PPV of CEUS and CECT LR-5 for the diagnosis of HCC were 89.5%, 95.0%, and 82.5%, 94.4%, respectively. The sensitivity of CEUS LR-5 + LR-M for the diagnosis of hepatic malignancies was higher than that of CECT (93.7% vs. 82.7%, p < 0.001). The specificity and PPV of CEUS LR-M for the diagnosis of non-HCC malignancies were lower than those of CECT (59.7% vs. 95.5%, p < 0.001; 23.4% vs. 70.3%, p < 0.001).ConclusionsThe inter-modality consistency between the CEUS and CECT LI-RADS categories is fair. CEUS LI-RADS was more sensitive than CECT LI-RADS in terms of identifying hepatic malignancies, but weaker in terms of separating HCC from non-HCC malignancies.

Two-stage method for hepatocellular carcinoma screening in B-mode ultrasound images

Background: Hepatocellular carcinoma (HCC) is a significant global health concern that requires early detection for effective treatment. Objectives: The objective of this study was to develop a system for screening HCC in B-mode ultrasound images. Materials and methods: The dataset consisted of 1665 hemangioma (HEM) images, including 961 typical HEM, 704 atypical HEM, and 543 HCC images. Four YOLOv4 models were trained: one for HCC detection, one for the conventional two-class detection of HEM and HCC, one to detect typical HEM and suspicious lesions, and the last one was our two-stage model consisting of a detector and classifier. In the first stage, a YOLOv4-based detector with ResNet-50 as the backbone was used to identify focal liver lesions. The second stage utilized ResNet-50 as a classifier to classify the lesions into HCC, atypical HEM, or typical HEM. Differentiating between HCC and atypical HEM is not necessary, as both require further investigation with CT or MR imaging. Results: The evaluation of the developed HCC screening system using ten-fold cross-validation showed that grouping HCC and atypical HEM together significantly increased precision from 0.74 to 0.88 and improved HCC recall from 0.64 to 0.68. Furthermore, employing the two-stage method further improved HCC recall from 0.68 to 0.72. Conclusion: The results indicate that combining HCC and atypical HEM into a single class and using a two-stage approach for detection led to substantial improvements in precision and HCC recall. These findings highlight the potential of the developed system for effective HCC screening in B-mode ultrasound images. The two-stage method provided better detection than the detector-only method. More accurate detection was achieved when lesions were classified based on appearance and clinical protocols.

Cancer Therapy-related Hepatic Injury in Children: Imaging Review from the Pediatric LI-RADS Working Group.

The liver is the primary organ for the metabolism of many chemotherapeutic agents. Treatment-induced liver injury is common in children undergoing cancer therapy. Hepatic injury occurs due to various mechanisms, including biochemical cytotoxicity, hepatic vascular injury, radiation-induced cytotoxicity, and direct hepatic injury through minimally invasive and invasive surgical treatments. Treatment-induced liver injury can be seen contemporaneous with therapy and months to years after therapy is complete. Patients can develop a combination of hepatic injuries manifesting during and after treatment. Acute toxic effects of cancer therapy in children include hepatitis, steatosis, steatohepatitis, cholestasis, hemosiderosis, and vascular injury. Longer-term effects of cancer therapy include hepatic fibrosis, chronic liver failure, and development of focal liver lesions. Quantitative imaging techniques can provide useful metrics for disease diagnosis and monitoring, especially in treatment-related diffuse liver injury such as hepatic steatosis and steatohepatitis, hepatic iron deposition, and hepatic fibrosis. Focal liver lesions, including those developing as a result of treatment-related vascular injury such as focal nodular hyperplasia-like lesions and hepatic perfusion anomalies, as well as hepatic infections occurring as a consequence of immune suppression, can be anxiety provoking and confused with recurrent malignancy or hepatic metastases, although there often are imaging features that help elucidate the correct diagnosis. Radiologic evaluation, in conjunction with clinical and biochemical screening, is integral to diagnosing and monitoring hepatic complications of cancer therapy in pediatric patients during therapy and after therapy completion for long-term surveillance. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material See the invited commentary by Ferraciolli and Gee in this issue.

Decreased Bleeding-Related Adverse Events Using Track Embolization with Gelatin Sponge Slurry after Percutaneous Liver Biopsy: A Propensity Score–Matched Study

PurposeTo evaluate the effectiveness of track embolization using gelatin sponge slurry in percutaneous ultrasound (US)-guided liver biopsy. Materials and MethodsAmong the 543 patients who underwent percutaneous US-guided liver biopsies between September 2018 and August 2021, 338 who did not undergo track embolization and 105 who underwent track embolization were included in the analysis. All procedures were performed with 18-gauge coaxial core biopsy needles. Patients’ laboratory data were reviewed. Patients in both groups were subdivided into the following 2 groups: (a) those with targeted biopsy for a focal liver lesion and (b) those with nontargeted biopsy for a liver parenchyma. Moreover, postbiopsy events, such as transfusion and transarterial embolization, were assessed. To minimize selection bias, propensity score matching (PSM) was performed. ResultsAfter PSM, all factors that could affect bleeding risk were well-matched and well-balanced between the 2 groups (P > .474). In the non-track embolization group, 17 (16.2%) patients experienced major or minor bleeding-related adverse events (AEs). In contrast, in the track embolization group, only 5 (4.8%) patients experienced major or minor bleeding-related AEs, which was significantly lower than that in the non-track embolization group (P = .007). All 5 (4.8%) cases of major bleeding-related AEs were observed in the non-track embolization group (P = .024). ConclusionsIn this study, a retrospective analysis was performed using PSM for percutaneous US-guided liver biopsy. Track embolization using gelatin sponge slurry is significantly superior in the prevention of bleeding-related AEs after US-guided liver biopsy.

Contrast-enhanced ultrasound with microbubbles containing sulfur hexafluoride and perfluorobutane with Kupffer phase for the detection of colorectal liver metastases.

To compare contrast-enhanced ultrasound (CEUS) with microbubbles containing sulfur hexafluoride (SHF) and perfluorobutane (PFB) for the detection of colorectal liver metastasis (CRLM). In this prospective study, conducted from September to November 2021, patients with colorectal cancer were consecutively recruited and underwent same-day ultrasound, SHF-CEUS, and PFB-CEUS. The reference standard was contrast-enhanced MRI and follow-up imaging. The size, depth, echogenicity, and calcification of each focal liver lesion were recorded. The number and conspicuity of CRLMs, based on washout appearance during the late phase (LP) (> 120 s)/Kupffer phase (KP), were evaluated offsite by two blinded readers. Overall, 230 lesions (CRLMs, n= 219; benign lesions, n= 11) in 78 patients were evaluated. Lesion conspicuity (p= 0.344) and accuracy in the detection of CRLM were comparable for SHF- and PFB-CEUS (0.877 for SHF vs. 0.770 for PFB, p= 0.087). More CRLMs ≥ 10 mm were identified by LP contrast washout in SHF-CEUS than in KP PFB-CEUS (p< 0.001). More CRLMs < 10 mm were identified by KP washout in PFB-CEUS than in LP SHF-CEUS (p< 0.001). Conspicuity was better on PFB-CEUS than on SHF-CEUS (p= 0.027). In hyperechoic lesions, lesions located deeper than 80 mm, and calcified lesions, CRLM conspicuity on PFB-CEUS was inferior to that on SHF-CEUS (p< 0.05). The overall accuracy of detection and conspicuity of washout in CRLMs were comparable between SHF and PFB-CEUS. PFB-CEUS has the advantage of identifying washout in small CRLMs. However, larger, hyperechogenic, deep-seated, or calcified lesions were better identified using SHF-CEUS. Accuracy of detection and conspicuity of washout in CRLMs were comparable between SHF- and PFB-CEUS. PFB-CEUS has the advantage in detecting small CRLMs, whereas SHF-CEUS is better for detecting larger, hyperechogenic, deep-seated, or calcified lesions. Contrast-enhanced ultrasound with sulfur hexafluoride in the late phase and perfluorobutane microbubbles in the Kupffer phase were comparable in terms of accuracy in the detection and conspicuity of colorectal liver metastases. Small colorectal liver metastases (< 10 mm) were more often identified in the Kupffer phase contrast-enhanced ultrasound imaging when using perfluorobutane microbubbles. Larger, hyperechogenic, deep-seated, or calcified lesions were better identified in the late phase contrast-enhanced ultrasound imaging (> 120 s) when using sulfur hexafluoride microbubbles.

Focal Lesions of the Liver and Radiomics: What Do We Know?

Despite differences in pathological analysis, focal liver lesions are not always distinguishable in contrast-enhanced magnetic resonance imaging (MRI), contrast-enhanced computed tomography (CT), and positron emission tomography (PET). This issue can cause problems of differential diagnosis, treatment, and follow-up, especially in patients affected by HBV/HCV chronic liver disease or fatty liver disease. Radiomics is an innovative imaging approach that extracts and analyzes non-visible quantitative imaging features, supporting the radiologist in the most challenging differential diagnosis when the best-known methods are not conclusive. The purpose of this review is to evaluate the most significant CT and MRI texture features, which can discriminate between the main benign and malignant focal liver lesions and can be helpful to predict the response to pharmacological or surgical therapy and the patient's prognosis.

Applications of Dynamic Contrast-Enhanced Ultrasound in Differential Diagnosis of Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma in Non-cirrhotic Liver.

The aim of the work described here was to investigate the value of dynamic contrast enhanced ultrasound (DCE-US) and quantitative analysis in pre-operative differential diagnosis of intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC) in non-cirrhotic liver. In this retrospective study, patients with histopathologically proven ICC and HCC lesions in non-cirrhotic liver were included. All patients underwent contrast-enhanced ultrasound (CEUS) examinations with an Acuson Sequoia unit (Siemens Healthineers, Mountain View, CA, USA) unit or LOGIQ E20 (GE Healthcare, Milwaukee, WI, USA) within 1 wk before surgery. SonoVue (Bracco, Milan, Italy) was used as the contrast agent. B-mode ultrasound (BMUS) features and CEUS enhancement patterns were analyzed. DCE-US analysis was performed by VueBox software (Bracco). Two regions of interest (ROIs) were set in the center of the focal liver lesions and their surrounding liver parenchyma. Time-intensity curves (TICs) were generated, and quantitative perfusion parameters were obtained and compared between the ICC and HCC groups using the Student t-test or Mann-Whitney U-test. From November 2020 to February 2022, patients with histopathologically confirmed ICC (n=30) and HCC (n=24) lesions in non-cirrhotic liver were included. During the arterial phase (AP) of CEUS, ICC lesions exhibited heterogeneous hyperenhancement (13/30, 43.3%), heterogeneous hypo-enhancement (2/30, 6.7 %) and rim-like hyperenhancement (15/30, 50.0%), whereas all HCC lesions exhibited heterogeneous hyperenhancement (24/24, 100.0%) (p < 0.05). Subsequently, most of the ICC lesions exhibited AP wash-out (83.3%, 25/30), whereas a few cases exhibited wash-out in the portal venous phase (PVP) (15.7%, 5/30). In contrast, HCC lesions exhibited AP wash-out (41.7%, 10/24), PVP wash-out (41.7%, 10/24) and a small part of late phase wash-out (16.7%, 4/24) (p < 0.05). Compared with those of HCC lesions, TICs of ICCs revealed earlier and lower enhancement during the AP, faster decline during the PVP and reduced area under the curve. The combined area under the receiver operating characteristic curve (AUROC) of all significant parameters was 0.946, with 86.7% sensitivity, 95.8% specificity and 90.7% accuracy in differential diagnosis between ICC and HCC lesions in non-cirrhotic liver, which improved the diagnostic efficacy of CEUS (58.3% sensitivity, 90.0% specificity and 75.9% accuracy). ICC and HCC lesions in non-cirrhotic liver might exhibit some overlap of CEUS features in diagnosis. DCE-US with quantitative analysis would be helpful in pre-operative differential diagnosis.