Endoscopic Ultrasound Elastography Research Articles

Do we need elastography for EUS?

We recently introduced a series of papers “What should be known prior to performing EUS exams.” In Part I, the authors discussed which clinical information and whether other imaging modalities are needed before embarking EUS examinations. In Part II, technical controversies on how EUS is performed were discussed from different points of view. In this article, important practical issues regarding EUS elastography will be raised and controversially discussed from very different points of view.

EUS Elastography for Predicting Cirrhotic-related Complications

EUS Elastography for Predicting Cirrhotic-related Complications

The Accurateness of Endoscopic Ultrasound Elastography in the Guidance of EUS-FNA in Solid Pancreatic Lesions

The Accurateness of Endoscopic Ultrasound Elastography in the Guidance of EUS-FNA in Solid Pancreatic Lesions

908 Diagnostic Value of Semi-Quantitative Endoscopic Ultrasound Elastography in the Evaluation of Mediastinal and Abdominal Lymph Nodes

INTRODUCTION: An accurate differentiation between benign and malignant lymph nodes (LN) is crucial for staging, risk stratification and treatment selection in patients with gastrointestinal malignancies. Endoscopic ultrasound (EUS) elastography can offer additional information that enables a better tissue characterization, enhancing the diagnostic power of EUS. The aim of this study was to evaluate the accuracy of the qualitative elasticity scores (ES) and semi-quantitative strain ratio (SR) for the diagnosis of abdominal and mediastinal LNs. METHODS: Consecutive patients referred for EUS evaluation of a mediastinal or abdominal LN by a single endosonographer (MSB) at a tertiary cancer center between January 2018 and May 2019 were included in the study. Elasticity scores (Table 1) and SR were determined during EUS exam. The final diagnosis was obtained by EUS-FNA cytology evaluation, surgical pathologic examination or clinical follow up. RESULTS: A total of 45 patients undergoing EUS evaluation of 70 LNs (40 benign, 30 malignant) were included in the analysis. According to the qualitative ES, the elastography images were interpreted as benign in 18 cases, malignant in 33 cases and indeterminate in 19. ES alone had a sensitivity of 100% and a specificity of 60% (Table 1). Based on the ROC curve analysis results, the best cut-off of SR to obtain the maximum area under the curve was 18.9, with a sensitivity of 47% and specificity of 85%. When both ES and SR were considered, the sensitivity was 100% with a specificity of 60% and negative predictive value of 100%. CONCLUSION: EUS elastography represents a promising method that allows the differential diagnosis of benign and malignant LN and it is complimentary to EUS-FNA. Given the high negative predictive value, EUS-elastography can decrease the number of unnecessary biopsies. The elasticity score and SR may be useful in patients with negative EUS-FNA results or in case in which a biopsy is not feasible.

Utility of EUS elastography in the diagnosis of gastric subepithelial tumors: a pilot study (with video)

EUS elastography is a real-time imaging technique that analyzes tissue elasticity. The aim of this study was to investigate the applicability of quantitative EUS elastography in the differential diagnosis of gastric subepithelial tumors (SETs). We prospectively registered 41 consecutive patients with gastric SETs and measured their strain ratios with EUS elastography. The strain ratios of gastric SETs were compared with the histopathologic diagnosis. Thirty-one patients (mean age, 51.4 ± 12.6 years) were included in the analysis. The mean size of the SETs was 2.3 ± 0.7 cm. Lipomas had the lowest strain ratio of 1.6 (1.1-2.0), followed by leiomyomas 6.0 (2.0-29.0), ectopic pancreas 11.8 (1.7-29.3), gastrointestinal stromal tumors (GISTs) 51.1 (29.0-67.0), and schwannomas 62.0. With a cut-off value of 22.7, EUS elastography could differentiate GISTs from leiomyomas with sensitivity and specificity of 100% and 94.1%, respectively (P= .001; 95% confidence interval, 0.979-1.000). EUS elastography could be a promising diagnostic adjunct for the assessment of gastric SETs, especially in differentiating GISTs from leiomyomas.

Tu1365 ENDOSCOPIC ULTRASOUND ELASTOGRAPHY AND CONTRAST ENHANCED ULTRASOUND ENDOSCOPY IN THE DIAGNOSIS OF SOLID PANCREATIC MASSES: A RETROSPECTIVE STUDY

Although endoscopic ultrasound elastography (EUS-EG) and contrast-enhanced harmonic endoscopic ultrasound (CE-EUS)have been proved to be highly accurate in the diagnosis of benign and malignant of pancreatic masses, there are few relevant studies on whether combined application of EUS-EG and CE-EUS can improve the accuracy compared with the single application.The present study was carried out to explore which of these new non-invasive EUS techniques is more reliable to the diagnosis of pancreatic masses, and whether the combination of EUS-EG and CE-EUS would be better than the application of either one of them in the diagnosis of pancreatic masses.

Ultrasound imaging of abdominal sarcoidosis: State of the art.

Since it has been recognized that sarcoidosis (SA) is not an exclusive disorder of the lungs but can also affect other organs such as the liver and spleen, efforts have been made to define specific imaging criteria for the diagnosis of the single organ involvement, and the concept has been reinforced that the exclusion of alternative causes is important to achieve the correct diagnosis. Ultrasound (US) is a useful tool to evaluate patients with suspected abdominal SA, such as of the liver, spleen, kidney, pancreas and other organs, showing findings such as organomegaly, focal lesions and lymphadenopathy. While the diagnosis of abdominal SA is more predictable in the case of involvement of other organs (e.g., lungs), the problem is more complex in the case of isolated abdominal SA. The recent use of contrast-enhanced ultrasound and endoscopic ultrasound elastography has provided additional information about the enhancement patterns and tissue rigidity in abdominal SA. Here we critically review the role of US in abdominal SA, reporting typical findings and limitations of current evidence and by discussing future perspectives of study.

Contrast-Enhanced EUS for Differential Diagnosis of Pancreatic Masses: A Meta-Analysis.

Background Though methods for the diagnosis of pancreatic masses are various, such as ultrasonography (US), computed tomography (CT), endoscopic ultrasonography (EUS), and contrast-enhanced computed tomography (CE-CT), their sensitivity, specificity, and accuracy are not quite satisfying. Contrast-enhanced endoscopic ultrasonography (CE-EUS), as a new technique, has its own unique advantages in diagnosing pancreatic disease. However, its sensitivity, specificity, and accuracy are still controversial. Objective To evaluate the accuracy of CE-EUS for differential diagnosis between benign and malignant pancreatic mass lesions. Design Eighteen relevant articles systemically searched from PubMed, Web of Science, Ovid, Scopus, and MEDLINE were selected. The pooled results were calculated in a fixed effects model. Main Outcome Measurement The pooled sensitivity, specificity, positive likelihood ratio (LR), negative likelihood ratio, diagnostic odds ratio (OR), and summary receiver operating characteristic (SROC) curve. Results The pooled sensitivity, specificity, and diagnostic odds ratio of CE-EUS for the differential diagnosis of pancreatic adenocarcinomas were 0.91 (95% confidence interval (CI), 0.89-0.93), 0.86 (95% CI, 0.83-0.89), and 69.50 (95% CI, 48.89-98.80), respectively. The SROC area under the curve was 0.9545. The subgroup analysis based on excluding the outliers showed that the heterogeneity was eliminated and the pooled sensitivity and specificity were 0.92 (95% CI, 0.90-0.93) and 0.87 (95% CI, 0.84-0.89), respectively. The SROC area under the curve was 0.9569. Conclusion CE-EUS is a useful method to distinguish pancreatic adenocarcinoma from other pancreatic diseases. Compared with EUS elastography, it has higher specificity. However, it is still not superior to pathological diagnosis for the identification of pancreatic carcinomas.

Determining resectability inpancreatic tumors: Review of 70 cases

Background: Endoscopic ultrasound (EUS) has gradually become the main stream method of the diagnosis and local treatment of pancreatic tumors. Endoscopic ultrasound (EUS) is frequently used in making the cytological diagnosis of pancreatic cancer and its great role in the pre-operative staging of pancreatic tumors.Objective: To evaluate the role of EUS in diagnosis and treatment of pancreatic tumors prospectively for 2 years study 2014-2015.Patients and methods: Prospective study including 70 patients who presented with pancreatic tumors underwent EUS at the endoscopy unit at Faculty of Medicine Cairo University and National Cancer Institute, Cairo University.Results: Out of 70 patients; median age was 55 years (range 32-73 years). Males were 32 (46%) and females were 38 (54%). Jaundice was the main symptom 47 (67%), clay colored stool 46 (65.7%), dark urine 47 (67%) and abdominal pain 50 (71%). There were 20 patients with benign disease and 50 patient with malignant disease. The following results showing the accuracy of the EUS in detecting malignant pancreatic tumors; Sensitivity: 96.0%, specificity: 75%, PPV: 90.6%, NPV: 88.2%, accuracy: 90.0%.Conclusion: EUS can clarify locoregional spread when CT/MR are equivocal. EUS Elastography is a new application in the field of the endosonography and seems to be able to differentiate fibrous and benign tissue from malignant lesions. The combination of superior detection, good staging, tissue diagnosis and potential therapy makes EUS guided FNA a cost-effective modality.

Diagnostic Efficacy of Endoscopic Ultrasound Elastography in Differentiating Solid Pancreatic Lesions: A Single-Center Experience.

Background/AimsEndoscopic ultrasound (EUS) has a limited ability to determine the nature of solid pancreatic lesions (SPLs). Most recent ultrasound processors are provided with elastography software, which allows quantification of the tissue hardness. The aim of this study is to evaluate the effectiveness of the elasticity score (ES) and strain ratio (SR) in the differentiation of benign pancreatic lesions from malignant pancreatic lesions. MethodsThe study had a retrospective design; it included 97 patients with SPLs and 19 patients with inflammatory lesions. The ES and SR were determined during the examination; finally, EUS-guided fine needle aspiration was performed. ResultsIn this 2-year study, 116 patients were enrolled (97 with malignant lesions and 19 with benign lesions). There were 69 men and 47 women. Their median age was 55.9 years. A cut-off point was detected at SR of 7.75 with a specificity of 99.9%, sensitivity of 90.7%, positive predictive value (PPV) of 99.9%, negative predictive value (NPV) of 67.9%, and accuracy of 92.2%. After adding the ES to the SR, the cut-off point at 7.75 resulted in a specificity of 94.6%, sensitivity of 99%, PPV of 98%, NPV of 98.5%, and accuracy of 97%. ConclusionsThe use of the ES combined with the SR increases the accuracy of differentiation between benign and malignant SPLs and is an effective method for the evaluation of pancreatic masses.

Diagnostic value of endoscopic ultrasound elastography for benign and malignant digestive system tumors.

Objective:To investigate the effect of endoscopic ultrasound real-time tissue elastography in differential diagnosis of benign and malignant digestive system tumors.Methods:Forty-two patients with solid tumors of digestive system who were admitted to our hospital between October 2017 and October 2018 were selected. All patients were diagnosed by endoscopic ultrasound real-time tissue elastography. Elastography score was used. The strain ratios (SR) of the lesion and the surrounding control tissues were measured and compared.Results:Lesions with elastography score no more than two points were evaluated as benign, while lesions with elastography score no less than three points were evaluated as malignant. The difference of the elastography score between the benign lesion group and malignant lesion group was statistically significant (P<0.05). The sensitivity, specificity and accuracy of endoscopic ultrasound elastography in the diagnosis of malignant tumors of digestive system were 91.4%, 88.9% and 87.5%, respectively. The SR of the benign lesions ranged from 0.01 to 7.34, with a median SR of 7.33; the SR of the malignant lesions ranged from 1.01 to 47.66, with a median SR of 20.07. The SR of the benign lesions was significantly lower than that of the malignant lesions (P<0.05).Conclusion:Elastography of benign and malignant tissues of digestive tract tumors has different image characteristics. Endoscopic ultrasound real-time tissue elastography is effective in differential diagnosis of digestive tract tumors as it can effectively determine whether a tumor is benign or malignant and improve diagnostic accuracy.

Video Comment on Andre Ignee et al.

Andre Ignee et al. Endoscopic ultrasound elastography of small solid pancreatic lesions: a multicenter study

Endoscopic Ultrasound Elastography for Evaluation of Lymph Nodes: A Single Center Experience.

Background and Aim The differentiation between malignant and benign lymph nodes (LNs) is important for tumor staging, for detection of prognosis, and for selection of the best treatment strategy in many cancers. On B-mode EUS, there are some known criteria that suggest the malignant nature of LNs; these criteria may be found in benign LNs. The aim of the work is to evaluate the effectiveness of elasticity score and SR to differentiate between benign and malignant LNs. Patients and Methods The study was designed as a retrospective study that included 40 patients with abdominal or mediastinal LNs, either associated with primary masses or isolated, referred for EUS evaluation. Elasticity scores and SR were determined during the examination and finally, EUS-FNA was done at the end of the procedure. Results In this 2-years study, 40 patients were enrolled (24 malignant; 16 benign). There were 23 males and 17 females. Their mean age was 52.5 years (range: 28–77). ES alone had a specificity of 87.5%, sensitivity of 41.7%, PPV of 83.3%, NPV of 50%, and accuracy of 60%. Based on the ROC curve analysis results, the best cut-off level of SR to obtain the maximum area under the curve (AUC) was 6.7 with a specificity of 99.9%, sensitivity of 57.1%, PPV of 99.9%, NPV of 64%, and accuracy of 77.5%. Conclusion The use of elasticity score and SR increases the reliability of differentiation between benign and malignant LNs and can decrease the number of unnecessary biopsies.

Predicting post-operative pancreatic fistulae using preoperative pancreatic imaging: a systematic review.

Post-operative pancreatic fistulae (POPF) remain a major contributor to morbidity and mortality following pancreatic resection. Evidence for preoperative prediction of POPF based on cross-sectional imaging has not been systemically reviewed. This review aimed to determine whether preoperative imaging modalities can accurately predict the development of POPF. A systematic review of major reference databases was undertaken, according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, up to May 2018. There were 18 studies (2150 patients), seven used magnetic resonance imaging (MRI), five used computed tomography (CT) scans, four used transabdominal ultrasonography and one study each used MRI and CT and endoscopic ultrasonography elastography. All were retrospective, single-centre studies. Intensity of the pancreas signal relative to the spleen, liver or muscle was commonly used. Other studies compared signal intensity between unenhanced and post-contrast-enhanced pancreas, apparent diffusion coefficient values comparing normal parenchyma to fibrosis, perfusion fraction (f) of intravoxel incoherent motion diffusion-weighted imaging, or utilized a muscle-normalized signal intensity curve with signal intensity ratio or directly assessed pancreatic volume and duct width. Shear wave velocity measurement on transabdominal ultrasonography may reflect pancreas tissue fibrosis or stiffness and predict POPF. Most parameters used to predict the development of POPF were based on identifying imaging features of a fatty or fibrotic pancreas and main pancreatic duct diameter. A number of different and highly promising parameters have been used for preoperative prediction of POPF using ultrasound, MRI, CT or both. Large multicentre prospective studies are needed to determine which parameters most accurately predict POPF, using standardized definitions and methodology.

Endoscopic ultrasound (EUS) elastography and strain ratio, could it help in differentiating malignant from benign pancreatic lesions?

Evaluating the role of endoscopic ultrasound (EUS) elastography and strain ratio in differentiation between malignant and benign pancreatic lesions.Three hundred twenty-five patients with solid pancreatic lesions were enrolled in this prospective study from 2014 to 2017. EUS real-time elastography scoring and strain ratio were done to all patients and compared to the final diagnosis to assess its sensitivity, specificity, positive and negative predictive values (PPV and NPV) in differentiating malignant from benign lesions.A cut-off value of 4.2 we had sensitivity of 95%, specificity of 63%, PPV of 89%, NPV of 81%, and accuracy of 87%. Another cut-off value of 10.9 showed a sensitivity of 75%, specificity of 88%, PPV of 95%, NPV of 54%, and accuracy of 79%. Adding the elastography to the better cut-off value gave a sensitivity of 97%, specificity of 63%, PPV of 89%, NPV of 88%, and accuracy of 89%.Real-time elastography and strain ration are valuable in differentiating malignant from pancreatic lesions.

Detecting tumour response and predicting resectability after neoadjuvant therapy for borderline resectable and locally advanced pancreatic cancer.

This systematic review aimed to determine the accuracy of imaging modalities to predict resectability and R0 resection for borderline resectable (BRPC) or locally advanced pancreatic cancer (LAPC) after neoadjuvant therapy (NAT). A systematic search of major databases was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Fifteen studies identified 995 patients of which 683 had BRPC and 312 LAPC. Computed tomography (CT) scan was the most common modality for re-staging (n = 14), followed by positron emission tomography (PET)-CT (n = 3) and endosonography (EUS) (n = 2). Stable disease on RECIST criteria was found in 67% of patients (range 53-80%) with 20% demonstrating reduction in tumour size. A total of 60% of patients underwent surgery post-NAT (range 31-85%) with a R0 rate of 88% (range 57-100%). Accuracy for predicting R0 resectability and T-stage on CT scan was 71 and 49%. A reduction in SUVmax on PET-CT and reduction of tumour stiffness on EUS elastography positively correlated with resectability. More than half the patients undergo resection post-NAT for LAPC and BRPC. Stable, or reduction of, tumour disease may predict resectability. Reduction in tumour SUVmax on PET-CT and decreased tumour stiffness on EUS elastography may be potential markers of NAT response and resectability.

Endoscopic ultrasound elastography in the diagnosis of pancreatic masses: A meta-analysis

Background and aimsEndoscopic ultrasound (EUS) elastography is a novel non-invasive technique that can be used for distinguishing benign from malignant pancreatic masses. However, the studies have reported widely varied sensitivities and specificities. A meta-analysis was performed to assess the performance of EUS elastography for the differentiation of benign and malignant pancreatic masses. MethodsAll the eligible studies were searched by PubMed, Medline, Embase, and the Cochrane Library. Sensitivity, specificity, positive likelihood ratio (LR), negative LR, and area under the curve (AUC) were calculated to examine the accuracy. ResultsA total of nineteen studies which included 1687 patients were analyzed. The pooled sensitivity and specificity for the diagnosis of malignant pancreatic masses were 0.98 (95% confidence interval [CI] 0.96–0.99) and 0.63 (95% CI 0.58–0.69) for qualitative EUS elastography, 0.95 (95% CI 0.93–0.97) and 0.61 (95% CI 0.56–0.66) for quantitative EUS elastography, respectively. The positive and negative LR were 2.60 (95% CI 1.84–3.66) and 0.05 (95% CI 0.02–0.10) for qualitative EUS elastography, 2.64 (95% CI 1.82–3.82) and 0.10 (95% CI 0.06–0.16) for quantitative EUS elastography, respectively. The summary diagnostic odds ratio (DOR) and the AUC were 60.59 (95% CI 28.12–130.56) and 0.91 (Q* = 0.842) for qualitative EUS elastography, 30.09 (95% CI 15.40–58.76) and 0.93 (Q* = 0.860) for quantitative EUS elastography. ConclusionsOur meta-analysis shows that both qualitative and quantitative EUS elastography have high accuracy in the detection of malignant pancreatic masses, which could be used as a valuable complementary method to EUS-FNA for the differentiation of pancreatic masses in the future.

Endoscopic Ultrasound Elastography for Solid Pancreatic Lesions: Ready to Replace Fine‑needle Biopsy?

Endoscopic Ultrasound Elastography for Solid Pancreatic Lesions: Ready to Replace Fine‑needle Biopsy?

Endoscopic Ultrasound Elastography for Pancreatic Lesion Assessment

Elastography, a technology used to measure the elastic properties of a lesion during endoscopic ultrasound (EUS), has been performed for several years

Endoscopic ultrasound elastography of small solid pancreatic lesions: a multicenter study.

The prevalence of malignancy in patients with small solid pancreatic lesions is low; however, early diagnosis is crucial for successful treatment of these cases. Therefore, a method to reliably distinguish between benign and malignant small solid pancreatic lesions would be highly desirable. We investigated the role of endoscopic ultrasound (EUS) elastography in this setting. Patients with solid pancreatic lesions ≤ 15 mm in size and a definite diagnosis were included. Lesion stiffness relative to the surrounding pancreatic parenchyma, as qualitatively assessed and documented at the time of EUS elastography, was retrospectively compared with the final diagnosis obtained by fine-needle aspiration/biopsy or surgical resection. 218 patients were analyzed. The average size of the lesions was 11 ± 3 mm; 23 % were ductal adenocarcinoma, 52 % neuroendocrine tumors, 8 % metastases, and 17 % other entities; 66 % of the lesions were benign. On elastography, 50 % of lesions were stiffer than the surrounding pancreatic parenchyma (stiff lesions) and 50 % were less stiff or of similar stiffness (soft lesions). High stiffness of the lesion had a sensitivity of 84 % (95 % confidence interval 73 % - 91 %), specificity of 67 % (58 % - 74 %), positive predictive value (PPV) of 56 % (50 % - 62 %), and negative predictive value (NPV) of 89 % (83 % - 93 %) for the diagnosis of malignancy. For the diagnosis of pancreatic ductal adenocarcinoma, the sensitivity, specificity, PPV, and NPV were 96 % (87 % - 100 %), 64 % (56 % - 71 %), 45 % (40 % - 50 %), and 98 % (93 % - 100 %), respectively. In patients with small solid pancreatic lesions, EUS elastography can rule out malignancy with a high level of certainty if the lesion appears soft. A stiff lesion can be either benign or malignant.