Contrast-enhanced Harmonic Endoscopic Ultrasonography Research Articles

Usefulness of Contrast-Enhanced Harmonic Endoscopic Ultrasonography for Diagnosis of Malignancy in Intraductal Papillary Mucinous Neoplasm

Intraductal papillary mucinous neoplasms (IPMNs) have a wide pathologic spectrum and it can be difficult to diagnose malignancy, including pathological grade. The aim of this study was to evaluate contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for the diagnosis of malignant IPMN and IPMN-associated invasive carcinoma (invasive IPMC). From 5009 patients diagnosed with IPMN at Wakayama medical university between December 2009 and December 2021, 115 patients who underwent contrast-enhanced computed tomography (CE-CT), conventional EUS, CH-EUS, and surgical resection were enrolled. The detection of mural lesions was compared with pathological findings. Malignant IPMN and invasive IPMC were also assessed according to mural lesion size and vascularity on CH-EUS. CH-EUS and conventional EUS showed significantly higher accuracy than CE-CT in the detection of mural nodules (92%, 83%, and 72%, respectively) and diagnosis of malignant IPMN (75%, 73%, and 63%, respectively). An early wash-out pattern on CH-EUS was observed in significantly more patients with invasive IPMC than in those with low-, intermediate-, or high-grade dysplasia. When compared with CE-CT, CH-EUS was significantly more accurate for detecting mural nodules and more useful for diagnosing malignant IPMN. The vascular pattern on CH-EUS was also useful for diagnosing invasive IPMC.

The usefulness of endoscopic ultrasound in the diagnosis of gallbladder lesions.

Gallbladder tumors are neoplastic lesions; however, it can be difficult to distinguish between benign and malignant gall bladder tumors before surgery, although endoscopic ultrasound (EUS) is useful for differentiation. Fundamental B mode EUS (FB-EUS) and contrast-enhanced harmonic EUS (CH-EUS) are reported to be useful for the diagnosis of gallbladder tumor because they allow evaluation of polypoid lesion and gallbladder wall thickening. Scoring systems based on FB-EUS imaging are available for the diagnosis of malignant gallbladder polypoid lesions. The characteristic findings of malignant gallbladder polypoid lesions on CH-EUS include the presence of irregular intratumoral vessels and perfusion defects. The characteristic findings of malignant gallbladder wall thickening on FB-EUS include wall thickening >12 mm, hypoechoic internal echogenicity, inhomogeneous internal echo pattern, and disrupted wall layer, whereas CH-EUS findings include hypovascular enhancement and inhomogeneous contrast distribution pattern. In addition, FB-EUS and CH-EUS are useful for evaluating the stage of gallbladder carcinoma because they allow the evaluation of the depth of invasion of the gallbladder wall. It is usually difficult to obtain pathological evidence from gallbladder tumors before surgery and chemotherapy, even though the histological diagnosis is necessary for determining treatment policy. EUS-guided fine needle aspiration (EUS-FNA) is useful for obtaining pathological samples from gallbladder tumors before surgery and chemotherapy. The accuracy rate of EUS-FNA for gallbladder tumor is as high as 90%, but complications such as bile leakage and needle track seeding can be a problem, although it was reported that contrast-enhanced harmonic imaging is useful for avoiding them.

Diagnostic Dilemma of Biliopancreatic Contrast-Enhanced Harmonic Endoscopic Ultrasonography.

Background: The utility of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) alone in the biliopancreatic region appears to be limited because it is highly dependent on the experience and skill of the endoscopist. Therefore, the present study aimed to validate the efficacy of CH-EUS in clinical practice. Methods: Between January 2018 and March 2019, 301 consecutive patients who underwent CH-EUS were prospectively enrolled in this study. The diagnostic performance of CH-EUS was compared with that of dynamic computed tomography (CT), magnetic resonance imaging (MRI), and all combinations (i.e., CH-EUS, dynamic CT, and MRI) using a Bonferroni correction. A multiple logistic regression analysis was performed to extract each disease that allowed the CH-EUS diagnosis to be consistent with the final diagnosis. Results: In multiple comparisons of diagnostic performance, no significant differences were observed among dynamic CT, MRI, and CH-EUS (p = 1.00), but the diagnostic performance was significantly higher when all modalities were combined (p < 0.001). Moreover, only intraductal papillary mucinous neoplasm comprising adenoma or carcinoma (IPMN, n = 161) showed significance with respect to the agreement with the final diagnosis (p = 0.006). Conclusions: Our results showed that CH-EUS-based diagnosis of IPMN may be possible in clinical practice. On the contrary, to accurately diagnose biliopancreatic diseases other than IPMN, comprehensive diagnosis using multiple modalities may be necessary, rather than relying on CH-EUS alone.

Enhanced endoscopic ultrasound imaging for pancreatic lesions: The road to artificial intelligence.

Early detection of pancreatic cancer has long eluded clinicians because of its insidious nature and onset. Often metastatic or locally invasive when symptomatic, most patients are deemed inoperable. In those who are symptomatic, multi-modal imaging modalities evaluate and confirm pancreatic ductal adenocarcinoma. In asymptomatic patients, detected pancreatic lesions can be either solid or cystic. The clinical implications of identifying small asymptomatic solid pancreatic lesions (SPLs) of < 2 cm are tantamount to a better outcome. The accurate detection of SPLs undoubtedly promotes higher life expectancy when resected early, driving the development of existing imaging tools while promoting more comprehensive screening programs. An imaging tool that has matured in its reiterations and received many image-enhancing adjuncts is endoscopic ultrasound (EUS). It carries significant importance when risk stratifying cystic lesions and has substantial diagnostic value when combined with fine needle aspiration/biopsy (FNA/FNB). Adjuncts to EUS imaging include contrast-enhanced harmonic EUS and EUS-elastography, both having improved the specificity of FNA and FNB. This review intends to compile all existing enhancement modalities and explore ongoing research around the most promising of all adjuncts in the field of EUS imaging, artificial intelligence.

Contrast enhanced endoscopic ultrasound in the diagnosis of pancreatic metastases.

Less than 5% of pancreatic masses represent metastases and differentiation from primitive tumors using endo-scopic ultrasound (EUS) is difficult. The aim of our work was to assess the diagnostic value of contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) for pancreatic metastases. We retrospectively analyzed patients with pancreatic metastasis identified during a 8 year period in a tertiary medical center. We included in the study 20 patients evaluated with EUS and CH-EUS. The primary tumor was localized in the kidney (6 cases), lung (5 cases), colon (3 cases), skin (2 patients) and stomach, breast, ovary and liver (1 patient each). Only 11 patients (55%) (kidney, lung, liver, ovary or skin metastases), presented hypervascularity at EUS and arterial hyperenhancement on CH-EUS, with similar diag-nostic value. All renal metastases were hyperenhanced (the negative predictive value 100%) and the stomach, colon and ovary metastases were hypoenhanced. The fast wash-out of contrast substance was encountered in all cases or renal, pulmonary and digestive metastases, but with 53.3-64.3% specificity for the different origin of pancreatic metastases. The vascularity assessments on conventional EUS or CH-EUS are similar for pancreatic metastases of different origin. EUS tissue acquisition remains mandatory for the diagnosis.

Contrast-enhanced harmonic endoscopic ultrasonography for predicting the efficacy of first-line gemcitabine and nab-paclitaxel chemotherapy in pancreatic cancer

Background and aimsThe purpose of this study was to assess prognosis with different intratumoral vascularity on contrast-enhanced endoscopic harmonic ultrasonography (CH-EUS) in pancreatic cancer patients receiving chemotherapy. MethodsPatients with unresectable pancreatic cancer who underwent CH-EUS before first-line gemcitabine and nab-paclitaxel (GEM and nab-PTX) therapy were classified into four groups according to vascularity on the early and late phases of contrast enhancement: “Group A″, poor on both phases; “Group B″, rich and poor on the early and late phases, respectively; “Group C″, poor and rich on the early and late phases; “Group D″, rich on both phases. Subgroups were compared in terms of progression-free survival (PFS) and overall survival (OS). We also assessed whether the results with CH-EUS correlate with those of contrast-enhanced computed tomography (CE-CT). ResultsOn CH-EUS, 57, 64, 0, and 24 patients were classified into Groups A, B, C, and D, respectively. The median PFS of patients in groups A, B, and D was 3.9, 7.6, and 10.8 months, respectively, and the median OS were 9.5, 13.1, and 18.6 months, respectively. Both PFS and OS were longest in Group D (p < 0.001 and p < 0.001, respectively). The results of CE-CT were consistent with those of CH-EUS, and there was a correlation between CE-CT and CH-EUS. ConclusionsEvaluation of intratumoral vascularity by CH-EUS may be useful for predicting the efficacy of chemotherapy in patients with pancreatic cancer. A better response to GEM and nab-PTX can be expected in patients showing rich vascularity at both the early and late phases.

Comparison of endoscopic ultrasonography with and without contrast enhancement for characterization of pancreatic tumors: a meta-analysis.

Background and study aims Endoscopic ultrasonography (EUS) is a reliable and efficient modality for detecting pancreatic tumors; however, plain EUS (P-EUS) is limited with respect to characterization of pancreatic tumors. Recently, the use of contrast-enhanced harmonic EUS (CH-EUS) has increased, and its utility for characterization of pancreatic tumors has been reported. This meta-analysis compares the diagnostic ability of P-EUS with that of CH-EUS for characterization of pancreatic tumors. Methods A systematic meta-analysis of all potentially relevant articles in PubMed, the Cochrane library, and Google Scholar databases was performed. Fixed effects or random effects models were used to investigate pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio, with 95 % confidence intervals (CIs). Results This meta-analysis included 719 patients who underwent CH-EUS and 723 who underwent P-EUS, from six eligible studies. The pooled estimates of sensitivity, specificity, and diagnostic odds ratio were 93 % (95 % CI, 0.90–0.95), 80 % (95 % CI, 0.75–0.85), and 57.9 (95 % CI, 25.9–130), respectively, for CH-EUS, and 86 % (95 % CI, 0.82–0.89), 59 % (95 % CI, 0.52–0.65), and 8.3 (95 % CI, 2.8–24.5) for P-EUS. The areas under the summary receiver operating characteristics curves for CH-EUS and P-EUS were 0.96 and 0.80, respectively. The diagnostic odds ratio for pancreatic cancer was 2.98 times higher on CH-EUS than on P-EUS ( P = 0.03). Funnel plots demonstrated no publication bias. Conclusions This meta-analysis demonstrates that CH-EUS has higher diagnostic accuracy for pancreatic cancer than P-EUS, and is thus a valuable tool for characterization of pancreatic tumors.

Value of artificial intelligence with novel tumor tracking technology in the diagnosis of gastric submucosal tumors by contrast-enhanced harmonic endoscopic ultrasonography.

Contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) is useful for the diagnosis of lesions inside and outside the digestive tract. This study evaluated the value of artificial intelligence (AI) in the diagnosis of gastric submucosal tumors by CH-EUS. This retrospective study included 53 patients with gastrointestinal stromal tumors (GISTs) and leiomyomas, all of whom underwent CH-EUS between June 2015 and February 2020. A novel technology, SiamMask, was used to track and trim the lesions in CH-EUS videos. CH-EUS was evaluated by AI using deep learning involving a residual neural network and leave-one-out cross-validation. The diagnostic accuracy of AI in discriminating between GISTs and leiomyomas was assessed and compared with that of blind reading by two expert endosonographers. Of the 53 patients, 42 had GISTs and 11 had leiomyomas. Mean tumor size was 26.4mm. The consistency rate of the segment range of the tumor image extracted by SiamMask and marked by the endosonographer was 96% with a Dice coefficient. The sensitivity, specificity, and accuracy of AI in diagnosing GIST were 90.5%, 90.9%, and 90.6%, respectively, whereas those of blind reading were 90.5%, 81.8%, and 88.7%, respectively (P=0.683). The κ coefficient between the two reviewers was 0.713. The diagnostic ability of CH-EUS results evaluated by AI to distinguish between GISTs and leiomyomas was comparable with that of blind reading by expert endosonographers.

Utility of contrast-enhanced harmonic EUS for diagnosis of portal vein invasion by pancreatic cancer.

The value of contrast-enhanced harmonic EUS (CH-EUS) for diagnosis of portal vein invasion in patients with pancreatic cancer was evaluated. This single-center, retrospective study included consecutive patients with pancreatic cancer who underwent both surgical resection after preoperative EUS, CH-EUS, and contrast-enhanced computed tomography (CE-CT) examinations between April 2015 and August 2017. CH-EUS evaluation was performed during the late phase. Portal vein invasion on EUS and CH-EUS was defined as no continuity in the line of the vessel wall. Definition of portal vein invasion on CE-CT was based on the Loyer's criteria. The accuracy of three modalities for diagnosis of invasion into the portal vein was compared using the McNemar's test. Eighty-eight patients (mean age: 71.0 years, ratio of male to female: 48:40) were eligible. Postoperative pathological results were as follows: seven cases of portal vein invasion; 81 cases without. Diagnostic accuracy of EUS, CH-EUS, and CE-CT for diagnosing invasion into the portal vein was 72.7%, 93.2%, and 81.8%, respectively. The differences between CH-EUS and CE-CT (P = 0.0094) and CH-EUS and EUS (P = 0.0022) were significant. EUS and CE-CT were comparable. CH-EUS is useful for diagnosis of portal vein invasion by pancreatic cancer.

Differentiation Between Solid Pseudopapillary Neoplasm of the Pancreas and Nonfunctional Pancreatic Neuroendocrine Neoplasm Using Endoscopic Ultrasound.

We investigated the utility of endoscopic ultrasound (EUS) for differentiating between solid pseudopapillary neoplasm of the pancreas (SPN) and pancreatic neuroendocrine neoplasm (PanNEN). A retrospective analysis was performed on 29 and 77 consecutive patients with pathologically proven SPN and nonfunctional PanNEN. In patients who underwent contrast-enhanced harmonic EUS (CH-EUS), lesions were classified into 3 vascular patterns (hypoechoic/isoechoic/hyperechoic), and the presence of "the alveolus nest sign," which we previously reported as a characteristic feature of SPN on CH-EUS, was also assessed. Conventional EUS findings showed that calcification echoes were significantly more frequent in SPN lesions than in PanNEN lesions (19/29 [66%] vs 21/77 [27%], P = 0.001) as was internal isoechogenicity or hyperechogenicity (10/29 [34%] vs 11/77 [14%], P = 0.029). Contrast-enhanced harmonic EUS findings showed that SPN lesions more frequently had the isoechoic or hypoechoic vascular pattern, and significantly more frequently had the alveolus nest sign (18/25 [72%] vs 4/60 [7%], P < 0.001). In a multivariate analysis, the presence of the alveolus nest sign contributed the most to the SPN diagnosis (odds ratio, 70; 95% confidence interval, 6.2-786). Endoscopic ultrasound, particularly the presence of the alveolus nest sign on CH-EUS, is useful for differentiating SPN from PanNEN.

Endoscopic ultrasound assessment and tissue acquisition of mediastinal and abdominal lymph nodes.

The differential diagnosis between benign and malignant lymph nodes (LNs) has a fundamental role in the characterization and staging of malignant conditions, as well as in subsequent patients’ management. All imaging modalities (i.e. computed tomography and magnetic resonance imaging) rely mainly on size; endoscopic ultrasound (EUS) criteria based on B-mode evaluation and Doppler features fail to adequately characterize with high specificity LNs nature. The introduction of EUS-elastography and contrast-enhanced harmonic EUS are useful techniques to increase the diagnostic yield in identifying metastatic LNs, to identify which suspicious LN should require pathological characterization and, finally, to target tissue acquisition. EUS-guided tissue acquisition (EUS-TA) is increasingly being used for diagnosing lymphadenopathy whenever the characterization modifies patients’ subsequent management and when no superficial LN is accessible. Since target therapy are currently available (i.e. lung cancer, breast cancer), EUS-TA of malignant LNs could be required to identify tumor biology. In this field, both fine needle aspiration and biopsy needles are able to guarantee accurate results with almost perfect specificity and sub-optimal sensitivity. We finally propose a diagnostic algorithm based on most recent, high-level evidence for the diagnostic approach to suspected LNs assessment.

The Role of Contrast-Enhanced Harmonic Endoscopic Ultrasound in Interventional Endoscopic Ultrasound

Over the last decades, contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) has emerged as an important diagnostic tool for the diagnosis and differentiation of several gastrointestinal diseases. The key advantage of CH-EUS is that the influx and washout of contrast in the target lesion can be observed in real time, accurately depicting microvasculature. CH-EUS is established as an evidence-based technique complementary to B-mode EUS to differentiate solid appearing structures, to characterize mass lesions, and to improve the staging of gastrointestinal and pancreatobiliary cancer. In the last few years, interest has increased in the use of CH-EUS in interventional procedures such as tissue acquisition, tumor ablation, biliary drainage, and the management of pancreatic fluid collections. The aim of this narrative review is to evaluate the available evidence and future expectations of CH-EUS in interventional EUS.

Imaging diagnosis of autoimmune pancreatitis using endoscopic ultrasonography.

The diagnosis of autoimmune pancreatitis (AIP) is challenging and should be achieved through the comprehensive evaluation of clinical, radiological, serological, and pathological evidence, as there is currently no single reliable diagnostic modality. Endoscopic ultrasonography (EUS) can reveal pancreatic parenchymal and ductal features in much more detail than any other existing imaging modality. In this article, we focused on three applications of EUS, i.e., conventional EUS imaging, EUS elastography (EUS-EG), and contrast-enhanced harmonic EUS (CEH-EUS), for the diagnosis of AIP. Diffuse hypoechoic areas, diffuse enlargement, bile duct wall thickening, and peripancreatic hypoechoic margins on conventional EUS are characteristic features of AIP, and the frequencies of these findings are significantly higher in AIP than in pancreatic cancer (PC). EUS-EG of the pancreatic parenchyma in AIP showed homogenous stiffness and that the elasticity of the pancreas may change after steroid therapy. CEH-EUS revealed focal or diffuse iso-enhancement in most AIP cases and hypo-enhancement in most PC cases. However, some AIP cases show a contrast enhancement pattern similar to that of PC. It should be noted that EUS findings of AIP may differ depending on its stage or disease activity. Differentiation from PC has become an increasingly important issue in the process of diagnosing AIP, and EUS, including elastography and contrast enhancement, could be a promising imaging modality for this purpose.

Utility of contrast-enhanced harmonic endoscopic ultrasonography for T-staging of patients with extrahepatic bile duct cancer.

The value of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for T-staging in patients with extrahepatic bile duct cancer was evaluated. This single-center, retrospective study included consecutive patients with extrahepatic bile duct cancer who underwent surgical resection after preoperative EUS, CH-EUS, and contrast-enhanced CT (CE-CT) examinations between June 2014 and August 2017. The capacity of these modalities for T-staging of extrahepatic bile duct cancer was evaluated by assessing invasion beyond the biliary wall into the surrounding tissue, gallbladder, liver, pancreas, duodenum, portal vein system (portal vein and/or superior mesenteric vein), inferior vena cava, and hepatic arteries (proper hepatic artery, right. and/or left. hepatic artery). Blind reading of EUS, CH-EUS, and CE-CT images was performed by two expert reviewers each. 38 patients were eligible for analysis, of which eight had perihilar bile duct cancer and 30 had distal bile duct cancer. Postoperative T-staging was T1 in 6, T2 in 16, and T3 in 16 cases. CH-EUS was superior to CE-CT for diagnosing invasion beyond the biliary wall into surrounding tissue (92.1% vs. 45.9%, P = 0.0002); the ability to detect invasion to other organs did not differ significantly between the two modalities. The accuracy of CH-EUS for T-staging of tumors was better than that of CE-CT (73.7% vs. 39.5%, P = 0.0059). CH-EUS tended to have a better accuracy than EUS for the diagnosis of invasion beyond the biliary wall into the surrounding tissue (92.1% vs. 78.9%, P = 0.074) and T-staging (73.7% vs. 60.5%, P = 0.074). CH-EUS is useful for T-staging of extra hepatic bile duct cancer, especially in terms of invasion beyond the biliary wall into the surrounding tissue.

Diagnosis of gastric submucosal tumors and estimation of malignant risk of GIST by endoscopic ultrasound. Comparison between B mode and contrast-harmonic mode

Backgroundstandard B-mode EUS assessment and EUS-guided tissue acquisition present sub-optimal diagnostic yield in the differential diagnosis of gastric submucosal tumors (SMTs). Aimsto evaluate the performances of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) to differentiate gastric SMTs and predict malignancy risk of gastrointestinal stromal tumors (GIST). Methodsa retrospective analysis was performed retrieving consecutive patients with gastric SMTs who underwent EUS between 2009 and 2014. Patients with available EUS video recordings and histological diagnosis were included. De-identified videos were presented to experts who made a diagnosis on B-mode EUS and CH-EUS. Resultsfifty-four patients (29 female, 64-year-old) were included. Final diagnoses were 40 GISTs (8 high-grade), 9 leiomyomas, 5 rare SMTs. The sensitivity, specificity, and accuracy of B-mode and CH-EUS for the differential diagnosis of GIST were 95.0% vs. 85.0%, 57.1% for both techniques, and 85.2% vs. 77.8%, respectively. The sensitivity, specificity, and accuracy of B-mode and CH-EUS for the estimation of the malignancy GISTs risk were 62.5% vs. 100%, 83.3% vs. 82.1%, and 78.9% vs. 86.1%, respectively. ConclusionsCH-EUS showed better diagnostic performance than B-mode EUS in differentiating leiomyomas and risk stratification of GIST. When considering high-grade GISTs, the addition of CH-EUS allowed an improvement in diagnostic accuracy.

Differentiation between pancreatic metastases from renal cell carcinoma and pancreatic neuroendocrine neoplasm using endoscopic ultrasound

ObjectivesPancreatic metastases from renal cell carcinoma (PRCC) often appear many years after treatment of the primary tumor, and differentiation from pancreatic neuroendocrine neoplasm (PanNEN) can be challenging due to their hypervascularity. Here, we investigated the utility of endoscopic ultrasound (EUS) for differentiation of these conditions. MethodsA retrospective analysis was performed in 17 and 79 consecutive patients with pathologically proven PRCC and non-functional PanNEN who were examined by EUS. In cases examined by EUS elastography or contrast-enhanced harmonic EUS (CH-EUS), the lesions were classified as stiff or soft, or into three vascular patterns as hypoechoic, isoechoic, and hyperechoic. CH-EUS images at 20 s, 40 s, 60 s, 3 min and 5 min were used for evaluation. EUS images were independently reviewed by two readers who were blinded to all clinical information. ResultsThe patients with PRCC were significantly older than those with PanNEN (median, 71 (range, 45–81) vs. 58 (22–76), P = 0.001) and more often had multiple tumors (6/17 (35%) vs. 7/79 (9%), P = 0.010). In EUS findings, PRCC lesions significantly more frequently had a marginal hypoechoic zone (MHZ) (11/17 (65%) vs. 27/79 (34%), P = 0.028), being classified as soft (12/13 (92%) vs. 26/58 (45%), P = 0.002), and showed sustained hyperechoic vascular patterns at 5 min (7/8 (88%) vs. 4/59 (7%), P < 0.001) compared to PanNEN lesions. ConclusionsThe presence of a MHZ, a soft lesion, and a sustained hyperechoic vascular pattern in EUS may be useful for differentiating PRCC from PanNEN.

The Role of Endoscopic Ultrasonography in the Differential Diagnosis of Polypoid Lesions of the Gallbladder: an Update

Although most gallbladder (GB) polyps are benign, some early carcinomas of the GB share the same appearance as benign polyps. Currently, GB polyps larger than 1 cm should be surgically removed because of the increased risk of malignancy. Distinguishing between nonneoplastic and neoplastic lesions is are a major diagnostic dilemma, and the therapeutic options for these lesions remain controversial. Endoscopic ultrasonography (EUS) is considered to be superior to the conventional US for imaging GB lesions since EUS can provide high-resolution images of small lesions with higher ultrasound frequencies. However, differential diagnosis remains difficult, especially for small GB polyps. Thus, various diagnostic methods using EUS have been introduced to overcome the difficulty of differential diagnosis between neoplastic and non-neoplastic polyps. Contrast-enhanced harmonic EUS is useful for observing microvascular patterns and additional enhancement images of GB polyps. This requires a post-recording analysis due to a short enhancement time. Real-time color Doppler-EUS provides the Doppler flow of vessels without a time limit. Keywords: Gallbladder, polyp; Endoscopic ultrasonography 중심 단어: ë‹´ë‚­ìš©ì¢ ; 내시경 초음파

Should Contrast-Enhanced Harmonic Endoscopic Ultrasound Be Incorporated into the International Consensus Guidelines to Determine the Appropriate Treatment of Intraductal Papillary Mucinous Neoplasm?

This study aimed to investigate whether the incorporation of contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) into the international consensus guidelines (ICG) for the management of intraductal papillary mucinous neoplasm (IPMN) could improve its malignancy diagnostic value. In this single-center retrospective study, 109 patients diagnosed with IPMN who underwent preoperative CH-EUS between March 2010 and December 2018 were enrolled. We analyzed each malignancy diagnostic value (sensitivity (Se), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV)) by replacing fundamental B-mode EUS with CH-EUS as the recommended test for patients with worrisome features (WF) (the CH-EUS incorporation ICG) and comparing the results to those obtained using the 2017 ICG. The malignancy diagnostic values as per the 2017 ICG were 78.9%, 42.3%, 60.0%, and 64.7% for Se, Sp, PPV, and NPV, respectively. The CH-EUS incorporation ICG plan improved the malignancy diagnostic values (Se 78.9%/Sp, 53.8%/PPV, 65.2%/NPV 70.0%). CH-EUS may be useful in determining the appropriate treatment strategies for IPMN.

Tissue harmonic versus contrast-enhanced harmonic endoscopic ultrasonography for the diagnosis of pancreatic tumors: Prospective multicenter study.

This prospective multicenter study aimed to assess and compare the accuracy of tissue harmonic endoscopic ultrasonography (TH-EUS) and contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for differentiating pancreatic carcinoma from other pancreatic tumors. Consecutive patients with solid pancreatic tumors were prospectively enrolled between August 2013 and December 2014. To assess the accuracy of TH-EUS and CH-EUS, we compared four parameters of TH-EUS (fuzzy edge, irregular periphery, hypoechogenicity, and heterogeneous internal echogenicity) and four parameters of CH-EUS (hypoenhancement and heterogeneous enhancement in the early and late phases, respectively) to investigate which parameter of each method was most suitable to diagnose pancreatic carcinomas. Interobserver agreement and the diagnostic ability of pancreatic carcinoma using TH-EUS and CH-EUS were assessed and compared. A total of 204 patients were enrolled. For the diagnosis of pancreatic carcinoma, interobserver agreement by experts and nonexperts was 0.33-0.50 and 0.35-0.50 for TH-EUS, respectively, and 0.72-0.74 and 0.20-0.54 for CH-EUS, respectively. Irregular periphery was the most accurate diagnostic parameter among TH-EUS findings for differentiating pancreatic carcinomas, with sensitivity, specificity, and accuracy of 95.0%, 42.9%, and 78.9%, respectively. Late phase hypoenhancement was the most accurate diagnostic parameter among CH-EUS findings for differentiating pancreatic carcinomas, with sensitivity, specificity, and accuracy of 90.8%, 74.6%, and 85.8%, respectively. The accuracy of CH-EUS (late phase hypoenhancement) for diagnosis of pancreatic carcinoma was significantly higher than that of TH-EUS (irregular periphery) (p < 0.001). In comparison with TH-EUS, CH-EUS increased the diagnostic ability and reproducibility for the diagnosis of pancreatic carcinoma. UMIN (000011124).

Role of CH-EUS as guidance for EUS-biliary drainage malignant obstruction.

Endoscopic ultrasound (EUS)-guided biliary drainage is the usual method of choice for patients with biliary obstructions difficult to treat by endoscopic retrograde cholangiopancreatography. In some patients, however, the bile duct is difficult to detect during EUS-guided biliary drainage. Contrast-enhanced harmonic endoscopic ultrasound has reportedly been useful for interventional EUS procedures. This study describes five patients who underwent EUS-guided biliary drainage with contrast-enhanced harmonic imaging between April 2017 and March 2020 for malignant biliary obstruction due to bile duct cancer. The procedure was performed through an intrahepatic bile duct approach in three patients and through an extrahepatic bile duct approach in the other two. Although fundamental B-mode EUS was unable to detect the target intrahepatic bile duct because the duct was filled with debris, contrast-enhanced harmonic imaging was able to detect the bile duct by clarifying its border with the hepatic parenchyma. Similarly, in patients who underwent extrahepatic bile duct approach, fundamental B-mode EUS could not distinguish between debris and tumor, whereas contrast-enhanced harmonic EUS was able to differentiate between them. The procedure was technically and clinically successful in all five patients. One patient experienced bleeding as an adverse event. In conclusion, EUS-guided biliary drainage with contrast-enhanced harmonic imaging is useful in detecting the fluid space in bile ducts filled with debris or filled with debris and tumor invasion.