Biopsy Of Focal Liver Lesions Research Articles

Endoscopic Ultrasound-Guided Fine Needle Biopsy of Focal Liver Lesions: An Effective Mini-Invasive Alternative to the Percutaneous Approach.

Despite the introduction of serological neoplastic biomarkers and typical radiological characteristics in clinical practice, liver biopsy (LB) is often still necessary to establish a histological diagnosis, especially in ambiguous cases. Nowadays, LB via the percutaneous approach (PC-LB), under computed tomography (CT) scan or ultrasonography (US) guidance, is the route of choice. However, certain focal liver lesions can be challenging to access percutaneously. In such cases, endoscopic ultrasound (EUS)-guided fine needle biopsy (FNB) may represent an attractive, minimally invasive alternative. This retrospective observational study aimed to evaluate the efficacy, diagnostic performance, and safety of EUS-FNB conducted on 58 focal liver lesions located in both liver lobes. The adequacy of FNB samples for focal liver lesions located in the left and right lobes was 100% and 81.2%, respectively, and the difference was statistically significant (p = 0.001). Technical success was 100% for both liver lobes. The overall sensitivity and specificity were 95% and 100%, respectively. EUS-FNB is effective in making an accurate diagnosis with an excellent safety profile for focal liver lesions located in both liver lobes.

Clinical value of contrast-enhanced ultrasound versus conventional ultrasound in biopsy of focal liver lesions.

Focal liver lesions (FLLs) are a common form of liver disease, and identifying accurate pathological types is required to guide treatment and evaluate prognosis. To compare and analyze the application effect of contrast-enhanced ultrasound (CEUS) and conventional ultrasound (US) in the clinical diagnosis of focal liver lesions. A retrospective analysis was performed on 682 patients with space-occupying liver lesions admitted to our hospital between December 2015 and August 2021. Of these, 280 underwent CEUS-guided biopsies and 402 underwent conventional US biopsies, with the results of each biopsy subsequently compared between the two groups. The success rate and accuracy of the biopsies and their relationship with different pathological features were also analyzed. The success rate, sensitivity, diagnostic accuracy, positive predictive value, and negative predictive value of the CEUS group were significantly higher than those of the US group (P < 0.05). Lesion size accuracy in the CEUS group was significantly higher than that in the US group (89.29% vs. 40.55%; P < 0.05). Lesion type accuracy in the CEUS group was significantly higher than that in the US group (86.49% vs. 43.59%), and the difference between the two groups was statistically significant (P < 0.05). The logistic regression analysis indicated that malignant lesions, lesions ≥5 cm, and lesions ≤1 cm were independent factors affecting the success rate of the puncture procedure (P < 0.05). The sensitivity, specificity, and diagnostic accuracy of lesion size and type in the CEUS group were higher than those in the US group.

Ultrasound-guided percutaneous biopsy for focal liver lesions: Adverse events and diagnostic yield in a single-centre analysis.

Ultrasound-guided biopsy of focal liver lesions (FLL) is a well-established procedure with crucial impact on therapeutic decisions. The safety and accuracy depend on needle type, tumour location and comorbidities. Modern oncological concepts often require large tumour specimens which may increase the procedural risk. We retrospectively collected data from consecutively scheduled ultrasound-guided FLL biopsies performed in an interdisciplinary ultrasound unit at a university hospital from 2015-2020. We analysed complication rates, diagnostic accuracy, and patient outcome in a one-year period. Of 426 scheduled interventions, 339 were included: 322 primary biopsies (40% female, median age 65 years, median BMI 25.4 kg/m2) and 17 rebiopsies in cases with undetermined diagnosis. Indications comprised 309 (96%) cases with suspected malignant lesions. Important comorbidities were type 2 diabetes (n = 107, 33%) and cirrhosis (n = 64, 20%). A conclusive histopathological diagnosis was achieved in 270 (84%) cases with a weak association with lesion size (OR 1.12 per cm, 95%CI 0.99-1.27). Greater BMI (OR 0.60 per 10 BMI points, 95%CI 0.34-1.05) showed a trend towards an insufficient diagnosis. Relevant complications occurred in 8 (2.5%) cases (2 major; 1 life-threatening). Multiple passes showed a trend towards adverse events (OR 2.32 for > 1 pass, 95%CI 0.99-5.42). 93 (29%) patients died during a median follow-up of 171 days. Ultrasound-guided FLL biopsy is an efficient and safe diagnostic measure. The limitations of the procedure and its associated risks should be considered in patients with advanced malignancies.

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

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 &gt;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.

Percutaneous CT-guided Biopsy of Focal Liver Lesions - Long- term Experience with more than 300 Procedures.

Despite the undeniable ongoing development of cross-sectional imaging methods, not all focal liver lesions (FLLs) have a typical pattern. An image-guided biopsy using a percutaneous approach might safely provide a final histological diagnosis of the FLLs. We aimed to evaluate the accuracy, efficiency, complication rate, technical features, and relationships between the followed parameters of computed tomography (CT)-guided percutaneous biopsies of FLLs using a retrospective approach. 303 percutaneous biopsy procedures in 295 patients were carried out in patients with suspected or indeterminate FLLs over a 10-year period. The median size of the tumors was 44 mm (15 - 144 mm). Median age of patients was 67 years (25 to 87 years). Skin-to-lesion distance was variable, from 30 mm to 138 mm (median length 59 mm). In 200 procedures (66%) malignant disease was known from the patients´ clinical history. In 288 biopsies (95%) the results were true positive or true negative; 15 procedures (4.95%) resulted in a histologically false negative and had to be confirmed using other approaches. Metastatic disease to hepatic parenchyma of various origins was the most frequent histological diagnosis (55.4%). Cholangiocarcinoma was the most common individual result (13.5%). In total 14 complications (4.6%) were confirmed, 4 of which were severe haemorrhages that needed angiographic treatment and in one case surgical revision. The mortality rate in our group was 0.3%. A statistically significant relationship between lesion size and diagnostic accuracy (p < 0.01) was revealed. The use of a 16 G needle calibre and at least two samples were suitable for hypo- and hypervascular lesions without a significant increase in the complication rate. Core needle biopsy using a percutaneous approach and a CT-guidance performed on patients with indetermined FLLs had a high overall accuracy in determining the final histological diagnosis including subtyping. Concurrently, the complication incidence was low.

Accuracy of endoscopic ultrasound-guided biopsy of focal liver lesions.

Endoscopic ultrasound (EUS) has become an indispensable method for diagnosis in gastroenterology and new indications for EUS continue to emerge. However, there are limited data regarding the accuracy of EUS-guided biopsy of hepatic focal lesions. The aim of this study was to assess the diagnostic yield of EUS-guided fine needle aspiration (FNA) of focal liver lesions. We conducted a prospective study in which patients with focal liver lesions, detected by transabdominal ultrasound and computed tomography or magnetic resonance imaging, underwent EUS-guided FNA to determine the diagnostic yield of the procedure. In 47/48 of patients, the results of EUS-FNA were positive for malignancy, while in one case the acquired fragment was insufficient for appropriate histological analysis. Diagnostic yield was 0.98. In 83% of the cases biopsies were taken from the left lobe and in 17% from the right lobe with the same technical success rate. The most common diagnosis was metastatic adenocarcinoma of the pancreas (26% cases) followed by cholangiocarcinoma (17% cases). Concurrent sampling of other sites in addition to the liver and/or primary tumor was realized in 35% of the cases, with results that correlated with the liver biopsy and with the primary tumor biopsy. We reported no immediate or long-term complications in any of the patients. EUS guided fine needle aspiration/biopsy of focal liver lesions is safe, provides a very high diagnostic accuracy and should not be considered only as a rescue method after failure of percutaneous guided biopsies.

Role of ultrasound contrast agent in a tertiary cancer center: Experience in 75 patients with liver biopsy.

e14671 Background: The sensitivity of B-mode ultrasound (US) in detecting hepatic lesions has been reported to be between 55-85%. A recently FDA approved US contrast agent has been shown to increase the detectability of liver lesions; yet, there is paucity of knowledge regarding its application in US guided biopsies. The aim of this study was to determine accuracy and applicability of contrast enhanced US (CEUS) guided biopsies of liver lesions in cancer patients. Methods: A prospective registry of 75 patients (M = 54%, F = 46%, Age: 63y±14), that underwent CEUS guided liver biopsy in 2017-2018, were retrospectively reviewed. The decision to apply US contrast was made based on pre-procedural and intra-procedural clinical findings. Lesions with negative biopsy results were reviewed in follow up imaging to determine any evidence of potential positive malignancy. Results: History of renal failure that precluded application of iodinated IV contrast was the main pre-procedural indication (17%). Intra-procedural indications included: poor visualization of lesions in B-mode US (78%), targeting enhancing part of lesions (necrotic, post ablation or cystic) (16%), and lesion selection (6%). Diameter of the lesions were ≤ 20mm in 46% of patients. Biopsy results were positive in 50 patients, and included 32% primary liver tumors (hepatocellular carcinoma and cholangiocarcinoma) and 68% metastasis (pancreas: 24%, breast: 12%, GI tract: 10%, lung: 8% and other: 14%). Of the 25 patients with negative biopsy results, 6 did not have follow up imaging and 3 were later found to have positive malignancy (Negative predictive value: 84%, accuracy: 96%). Genomic sequencing was established in 34% of the patients. Based on the biopsy/genomics results, patients underwent systemic treatment (56%), locoregional treatment (16%), combination (6%) or surgery (2%). 10% of patients selected hospice care and 10% lost follow up. Conclusions: CEUS increases the accuracy of US guided biopsies of focal liver lesions, by improving visualization, targeting viable parts and also in patients with renal failure, or small lesions. Findings from these biopsies could improve management of cancer patients by categorizing them into different treatment groups.

Clinical Usefulness of contrast-enhanced ultrasound for percutaneous biopsies of focal liver lesions

Purpose To determine the value of contrast-enhanced ultrasound (CEUS) for fusion–guided, percutaneous biopsies of focal liver lesions. Materials and Methods Eighty patients with focal liver lesions identified on CT/MRI were enrolled. For percutaneous US guided biopsy planning, real-time fusion of CT/MRI with USG was performed, and subsequently CEUS was performed using sulphur hexafluoride microbubble (SonoVue, n = 40) and perfluorobutane-containing microbubble (Sonazoid, n = 40). We evaluated visibility and technical feasibility confidence level. Technical failure and occurrence of change of the target were also assessed. Results Among the 80 patients, four were technical failure for image fusion and one were technical failure for CEUS. Confirmative histologic diagnostic results were reported in 72 patients (90%) and the remaining patients were also helpful for making the final diagnosis using pathology results. Targeted lesion was changed in 22 patients (27.5%) on CEUS. As the lesion is necrotic, presumed target was more frequently changed after CEUS. Confidence level of technical success of procedure was significantly increased on CEUS comparison with B-US (p Conclusion CEUS would be helpful for planning of hepatic biopsy in terms of tumor visibility and viable portion assessment, and consequently higher operator confidence, compared with B-US.

Diagnostic yield of endoscopic ultrasound-guided biopsy of focal liver lesions.

Endoscopic ultrasonography (EUS) has become an indispensable method for diagnosis and therapeutic procedures in gastroenterology. As experience with this technique grows, new indications continue to emerge. Due to the vicinity of the transducer to the liver, endoscopic ultrasonography provides detailed images of the liver segments and its vascular and biliary structures. Endosonographers have made an effort to define a clinical role for endoscopic ultrasound in liver diseases; however, not much is known about endoscopic ultrasound guided fine needle aspiration (EUS-FNA) in hepatic focal lesions.This review summarizes the available evidence regarding the usefulness of endoscopic ultrasound-guided fine needle aspiration in patients with focal liver lesions.

The Role of US Contrast Agents in US-Guided Biopsy of Focal Liver Lesions: A Pictorial Review.

US-guided percutaneous biopsy of focal liver lesions (FLL) is a classic interventional procedure performed by almost all radiology units. Typically, an incidental focal finding on US or a focal indeterminate lesion diagnosed on CT, MRI or PET/CT is referred for US-guided biopsy for final diagnosis. The introduction of microbubble US contrast agents has overcome some of the limitations of standard US in diagnosing FLLs by displaying the microvasculature together with the US morphology, which has increased both the sensitivity and the specificity. The combination of CEUS and intervention is facilitated by newer US equipment providing split-screen mode, which displays the CEUS mode alongside the standard US mode simultaneously on a single monitor. The puncture line is displayed in both modes as well as on the monitor. The interventional device (i. e., biopsy needle) is typically best visualized in the standard US mode, while the characteristic tissue pattern in an FLL is typically best visualized in CEUS mode. There are 3 main categories in which CEUS has an impact on US-guided biopsy of FLLs: • CEUS improves the visualization of FLLs • CEUS improves the quality of the biopsy specimen from an FLL • CEUS reduces the need for US-guided biopsy of an FLL In the two first categories, CEUS is utilized simultaneously with US-guided biopsy to ensure correct needle targeting. In the last category, US-guided biopsy of the FLL becomes superfluous as a result of the CEUS examination.

Additional value of contrast-enhanced ultrasonography for fusion-guided, percutaneous biopsies of focal liver lesions: prospective feasibility study.

To determine the value of CEUS for real-time, fusion-guided, percutaneous biopsies of focal liver lesions. Institutional review board approval and written informed consents were obtained for this study. Forty patients with focal liver lesions identified on CT/MRI were prospectively enrolled. For biopsy planning, real-time fusion of CT/MRI with USG (USG-Fusion) was performed, and subsequently real-time CEUS was fused with CT/MRI (CEUS-Fusion). We evaluated lesion visibility, confidence level of technical success before the procedure, and safety route accessibility on USG-Fusion and CEUS-Fusion. Occurrence of change in the biopsy target was also assessed. Among 40 target lesions, nine (22.5%) lesions were invisible on USG-Fusion. After applying CEUS-Fusion, seven of nine (77.8%) lesions were visualized. Confidence level of technical success of procedure was significantly increased on CEUS-Fusion compared USG-Fusion (p = 0.02), and presumed target lesions were changed in 16 (40%) patients after CEUS-Fusion. As the lesion is necrotic, presumed target was more frequently changed after CEUS-Fusion (50.0% and 25.0%). Confirmative diagnostic results were reported in 39 (97.5%) patients. Accessibility of the safety route to target lesions did not reach statistical differences. Applying a new, real-time CEUS-Fusion with CT/MRI improved tumor visibility and viable portion assessment, thus leading to higher operator confidence and diagnostic yield, when compared with conventional USG-Fusion.

Clinical utility of real-time ultrasound-multimodality fusion guidance for percutaneous biopsy of focal liver lesions

ObjectivesTo prospectively evaluate the clinical value of real-time ultrasonography (US)—computed tomography (CT)/magnetic resonance imaging (MRI) fusion imaging for percutaneous needle biopsy of focal liver lesions (FLLs), and to compare its biopsy success rate with that of conventional US-guided biopsy in a propensity-score matched group. MethodsThis study was approved by our Institutional Review Board and informed consent was obtained from all patients enrolled in the prospective study group. Ninety patients referred to the Department of Radiology for percutaneous biopsy of FLLs were enrolled in this study. Tumor visibility, attainment of a safe access route, and technical feasibility were assessed on conventional US first and later on real-time fusion imaging by one of four abdominal radiologists. Thereafter, differences in scores between real-time fusion imaging and conventional US were determined. In addition, overall diagnostic success rates of a real-time fusion imaging-guided biopsy group and a propensity-score matched, conventional US-guided biopsy group, consisting of 100 patients used as historical control, were compared. ResultsWith real-time fusion imaging, tumor visibility, attainment of a safe access route, and operator’s technical feasibility were significantly improved compared with conventional US (P < .001). In addition, all invisible (n = 13) and not feasible (n = 10) FLLs on conventional US became visible and feasible for percutaneous US-guided biopsy after applying the fusion system. The diagnostic success rate of real-time fusion-guided biopsy was 94.4% (85/90), which was significantly better than that obtained with the conventional US-guided biopsy (94.4% vs. 83%, P < .03), with reduced biopsy procedure times (7.1 ± 3.5 vs. 9.7 ± 2.8, P < .02). ConclusionsReal-time US-CT/MR fusion imaging guidance was able to provide clinical value for percutaneous needle biopsy of FLLs by improving the diagnostic success rate of biopsy and by reducing procedure time.

Contrast enhanced ultrasound guided biopsies of liver lesions not visualized on standard B-mode ultrasound-preliminary experience.

To assess the technical success of contrast enhanced ultrasound (CEUS) guided biopsies of liver lesions poorly visualized on B-mode ultrasound. Patients were selected during the procedure based on the real-time clinical scenario of unsatisfactory B-mode ultrasound lesion visualization and all patients would have otherwise undergone CT guided liver lesion biopsy. A total of 26 patients underwent CEUS guided biopsy and were included in this retrospective analysis. The review of the patients' files included demographic information, lesion characteristics on imaging, procedural details and pathology outcome. Technical success was defined as concordance between the radiological findings, pathology report and clinical follow-up-demonstrating lack of need for re-biopsy or re-biopsy with identical pathological results. Patients with less than 2 months follow-up were excluded from the study. CEUS guided liver biopsy was successful in 23 out of 26 patients (88.5%). The average procedure time was 30.7±12.3 minutes and the average lesion size was 2.2±1.7 cm. The majority of lesions (80.8%) were hypoenhancing on the delayed phase of CEUS. The mean number of samples taken from each lesion per procedure was 3.2 (±1.7). CEUS guidance biopsies of focal liver lesions (FLL) that were difficult to visualize on B-mode ultrasound demonstrated high success rate and may be an evolving image guidance modality in selected patients to avoid CT guided procedures.

Magnetic-resonance-guided biopsy of focal liver lesions.

Image-guided biopsy techniques are widely used in clinical practice. Commonly used methods employ either ultrasound (US) or computed tomography (CT) for image guidance. In certain patients, US or CT guidance may be suboptimal, or even impossible, because of artifacts, suboptimal lesion visualization, or both. We recently began performing magnetic resonance (MR)-guided biopsy of focal liver lesions in select pediatric patients with lesions that are not well visualized by US or CT. This report describes our experience performing MR-guided biopsy of focal liver lesions, with case examples to illustrate innovative techniques and novel aspects of these procedures.

Navigated MRI-guided liver biopsies in a closed-bore scanner: experience in 52 patients.

ObjectivesTo evaluate clinical effectiveness and diagnostic efficiency of a navigation device for MR-guided biopsies of focal liver lesions in a closed-bore scanner.MethodsIn 52 patients, 55 biopsies were performed. An add-on MR navigation system with optical instrument tracking was used for image guidance and biopsy device insertion outside the bore. Fast control imaging allowed visualization of the true needle position at any time. The biopsy workflow and procedure duration were recorded. Histological analysis and clinical course/outcome were used to calculate sensitivity, specificity and diagnostic accuracy.ResultsFifty-four of 55 liver biopsies were performed successfully with the system. No major and four minor complications occurred. Mean tumour size was 23 ± 14 mm and the skin-to-target length ranged from 22 to 177 mm. In 39 cases, access path was double oblique. Sensitivity, specificity and diagnostic accuracy were 88 %, 100 % and 92 %, respectively. The mean procedure time was 51 ± 12 min, whereas the puncture itself lasted 16 ± 6 min. On average, four control scans were taken.ConclusionsUsing this navigation device, biopsies of poorly visible and difficult accessible liver lesions could be performed safely and reliably in a closed-bore MRI scanner. The system can be easily implemented in clinical routine workflow.Key Points• Targeted liver biopsies could be reliably performed in a closed-bore MRI.• The navigation system allows for image guidance outside of the scanner bore.• Assisted MRI-guided biopsies are helpful for focal lesions with a difficult access.• Successful integration of the method in clinical workflow was shown.• Subsequent system installation in an existing MRI environment is feasible.

Efficacy, safety and diagnostic accuracy of ultrasound guided biopsies of focal liver lesions: a single center experience in 214 patients

Background and aims: Histological assessment represents an important tool in the diagnostic evaluation of focal liver lesions. In this study, we analyzed the safety and efficacy and diagnostic accuracy of ultrasound guided biopsies of focal liver lesions in 212 patients. Methods: 212 ultrasound guided liver biopsies were retrospectively evaluated. All lesions were initially detected by ultrasound or CT-scan. Additional contrast enhanced ultrasound (CEUS) was performed in 98 patients previous to liver biopsy. Biopsies were performed under sterile conditions with a 16 or 18 G biopsy needle and a special ultrasound biopsy probe. Two or three biopsy specimens of the same focal lesion were obtained from each patient to increase diagnostic accuracy. Results: In 93% of the cases, liver histology lead to the correct diagnosis of the underlying disease. 39% of the patients had primary hepatobiliary neoplasia (59 cases with hepatocellular carcinoma, 20 cases with cholangiocellular carcinoma and 4 cases with HCC/CCC mixed tumor). In 37% the biopsy revealed a hepatic metastasis of a primary extrahepatic malignoma. 10% of the lesions were benign, 3% were liver abscesses of infectious diseases. In 7% of the biopsies, liver histology resulted in false negative results thus either ultrasound guided or CT-guided re-biopsy was necessary. In concordance with other diagnostic results, neoplasia could be excluded by liver histology in 5% of the patients. Overall CEUS correlated in 86% with the histological findings. However, in patients with histologically proven malignoma correlation to CEUS was 97%. Only two patients experienced clinically relevant postinterventionel bleeding, otherwise no significant complications occurred. Conclusion: Ultrasound guided biopsy represents a safe and efficient diagnostic tool in obtaining histological specimens of focal liver lesions. Furthermore, CEUS has a high predictive value regarding the etiology of the focal liver lesions.

Evaluation of Analgesic Effect of Equimolar Mixture of Oxygen and Nitrous Oxide Inhalation During Percutaneous Biopsy of Focal Liver Lesions:: A Double-blind Randomized Study

Percutaneous liver biopsy for tumors performed under local anesthesia is still a painful procedure. The aim of this study was to evaluate the patient's reaction and the analgesic efficacy and safety of an equimolar mixture of oxygen and nitrous oxide (EMONO) inhalation. A monocenter, prospective, randomized and double-blind controlled study was performed including 99 adult patients undergoing ultrasound controlled liver biopsy for tumors. 50 patients received an EMONO and 49 patients received a placebo. Pain was evaluated by patients before and after the procedure using a Visual Analog Scale. Analgesic control, defined by the difference between the final and initial VAS scores (Δ), was significantly better in the EMONO group than in the placebo group (Δ = 17.8 ± 25.5 mm vs 30.1 ± 32.6 mm; P = .045. The number of patients who would agree to undergo another liver biopsy under the same conditions was significantly higher in the EMONO group than the placebo group (92.0% vs 75.5%, P = .026). There were no side-effects from the administration of an EMONO. This study shows that patients receiving an EMONO had a higher analgesic control after percutaneous biopsy of focal liver lesions than patients in the placebo group. Moreover, acceptance of additional biopsies was higher in the EMONO group.

Efficacy, safety and diagnostic accuracy of ultrasound guided biopsies of focal liver lesions: a single center experience in 99 patients

Efficacy, safety and diagnostic accuracy of ultrasound guided biopsies of focal liver lesions: a single center experience in 99 patients

6608 Evaluation of analgesic effect of N2O/O2 inhalation, during percutaneous biopsy of focal liver lesions: a randomized study

6608 Evaluation of analgesic effect of N2O/O2 inhalation, during percutaneous biopsy of focal liver lesions: a randomized study