Role of endoscopic ultrasound-guided biliary drainage for palliation of malignant biliary obstruction

Endoscopic ultrasound-guided biliary drainage(EUS-BD)directs bile flow into the digestive tract and has been mostly used in patients with malignant biliary obstruction(MBO)where endoscopic retrograde cholangiopancreatography-guided biliary drainage was unsuccessful or was not feasible.Lumen apposing metal stents(LAMS)are deployed during EUS-BD,with the newer electrocautery-enhanced LAMS reducing procedure time and complication rates due to the inbuilt cautery at the catheter tip.EUS-BD with electrocautery-enhanced LAMS has high technical and clinical success rates for palliation of MBO,with bleeding,cholangitis,and stent occlusion being the most common adverse events.Recent studies have even suggested comparable efficacy between EUS-BD and endosc-opic retrograde cholangiopancreatography as the primary approach for distal MBO.In this editorial,we commented on the article by Peng et al published in the recent issue of the World Journal of Gastrointestinal Surgery in 2024.

Comparison of Cognitive Registration Transrectal Ultrasound-Guided Targeted Biopsy of Prostate to Systematic 12-Core Biopsy: A Retrospective, Multicentre Study

Introduction: Prostate cancer (PCa) is the third most prevalent cancer among Malaysian males, often diagnosed at advanced stages, leading to suboptimal outcomes. While transrectal ultrasound-guided systematic biopsy (TRUS-SB) is the primary diagnostic method, prebiopsy multiparametric magnetic resonance imaging (mpMRI) is gaining popularity in identifying suspicious lesions. This study addresses the lack of comprehensive investigations into the efficacy of cognitive registration TRUS targeted biopsy (COG-TB) compared to conventional TRUS-SB, considering the resource limitations of the Malaysian healthcare system. Materials and Methods: A retrospective cohort study was conducted in two Malaysian healthcare facilities. 116 adult patients with a prostate-specific antigen (PSA) level of more than 4 ng/mL who underwent both COG-TB and TRUS-SB between October 2020 and March 2022 were included. Primary outcomes were cancer detection rate and histopathological outcomes, including Gleason score. Results: COG-TB showed a higher overall cancer detection rate (50%) compared to TRUS-SB (44%). Clinically significant cancer detection rates were similar between COG-TB and TRUS-SB (37.1%). Further analysis revealed that both COG-TB and TRUS-SB detected clinically significant cancer in 30.2% of patients, did not detect it in 56.0%, and had conflicting findings in 16 patients (p Conclusion: COG-TB and TRUS-SB have comparable detection rates for clinically significant prostate cancer, with COG-TB showing a higher tendency to detect insignificant prostate cancer. Further studies comparing these methods are warranted.

Endoscopic ultrasound-guided fine-needle aspiration pancreatic adenocarcinoma samples yield adequate DNA for next-generation sequencing:A cohort analysis

BACKGROUND Genetic tests are increasingly performed for the management of unresectable pancreatic cancer.For genotyping aimed samples current guidelines recommend using core specimens,although based on moderate quality evidence.However,in clinical practice among the endoscopic ultrasound(EUS) guided tissue acquisition methods,fine needle aspiration(FNA) is the most widely performed.AIM To assess the adequacy for next generation sequencing(NGS) of the DNA yielded from EUS-FNA pancreatic adenocarcinoma(PDAC) samples.METHODS Between November 2018 and December 2021,105 patients with PDAC confirmed by EUS-FNA were included in the study at our tertiary gastroenterology center.Either 22 gauge(G) or 19G FNA needles were used.One pass was dedicated to DNA extraction.DNA concentration and purity(A260/280,A260/230) were assessed by spectrophotometry.We assessed the differences in DNA parameters according to needle size and tumor characteristics(size,location) and the adequacy of the extracted DNA for NGS(defined as A260/280 ≥ 1.7,and DNA yield:≥ 10 ng for amplicon based NGS,≥ 50 ng for whole exome sequencing [WES],≥ 100 ng for whole genome sequencing [WGS]) by analysis of variance and ttest respectively.Moreover,we compared DNA purity parameters across the different DNA yield categories.RESULTS Our cohort included 49% male patients,aged 67.02 ± 8.38 years.The 22G needle was used in 71%of the cases.The DNA parameters across our samples varied as follows:DNA yield:1289 ng(inter quartile range:534.75-3101),A260/280 = 1.85(1.79-1.86),A260/230 = 2.2(1.72-2.36).DNA yield was > 10 ng in all samples and > 100 ng in 93% of them(one sample < 50 ng).There were no significant differences in the concentration and A260/280 between samples by needle size.Needle size was the only independent predictor of A260/230 which was higher in the 22G samples(P =0.038).NGS adequacy rate was 90% for 19G samples regardless of NGS type,and for 22G samples it reached 89% for WGS adequacy and 91% for WES and amplicon based NGS.Samples with DNA yield > 100 ng had significantly higher A260/280(1.89 ± 0.32 vs 1.34 ± 0.42,P = 0.013).Tumor characteristics were not corelated with the DNA parameters.CONCLUSION EUS-FNA PDAC samples yield DNA adequate for subsequent NGS.DNA amount was similar between 22G and 19G FNA needles.DNA purity parameters may vary indirectly with needle size.

Endoscopic ultrasound guided biliary drainage in surgically altered anatomy: A comprehensive review of various approaches

Endoscopic retrograde cholangiopancreatography(ERCP)is the preferred modality for drainage of the obstructed biliary tree.In patients with surgically altered anatomy,ERCP using standard techniques may not be feasible.Enteroscope assisted ERCP is usually employed with variable success rate.With advent of endoscopic ultrasound(EUS),biliary drainage procedures in patients with biliary obstruction and surgically altered anatomy is safe and effective.In this narrative review,we discuss role of EUS guided biliary drainage in patients with altered anatomy and the various approaches used in patients with benign and malignant biliary obstruction.

Comparison of Transrectal Prostate Digital and Ultrasound-Guided Core Biopsies in 400 Men in a Low-and-Middle Income Country

Background: The diagnosis of prostate cancer (PCa) relies on clinical assessment with digital rectal examination, serum PSA and histological examination. Limitations in our technical facilities, high financial cost of ultrasound-guided biopsy often prevent us from implementing the guidelines on the practice of prostate biopsy. Methods: We conducted a retrospective and cross-sectional descriptive study comparing digital-guided and ultrasound-guided transrectal prostate biopsy of 400 patients over a period of 12 years in the Yaounde Central Hospital. We reviewed files of patients who underwent digital and ultrasound guided biopsy procedures. Data was analyzed using EPI info 7.0. Parametric variables were reported as means and standard deviations and percentages and counts were used to report categorical variables. Results: Out of the 400 patients, 292 digital-guided transrectal biopsies (73%) and 108 ultrasound-guided transrectal biopsies (27%) were performed in patients who were suspected of having prostate cancer (PCa). Patients were aged between 39 to 90 years. Both procedures were effective in identifying prostate cancer. Gleason score between 2 to 10 detected prostate adenocarcinoma for 301 patients (75.2%). The complications included anal pain, rectal bleeding, hematuria and urinary tract infections, with an occurrence rate similar for both ultrasound-guided (2.25%) and digitally-guided techniques (2.5%). Seven patients (1.75%) required hospitalization for management of complications. The mortality rate was null. Conclusion: Both techniques are effective in detecting PCa with the similar complication rates. Digital-guided trans-rectal prostate biopsy still has its place in a resource-limited setting like ours.

Endoscopic ultrasound guided gastroenterostomy:Technical details updates,clinical outcomes,and adverse events

Endoscopic ultrasound-guided gastroenterostomy(EUS-GE)has been transformed from an innovative technique,into a viable alternative to enteral stenting and surgical gastrointestinal anastomosis for patients with gastric outlet obstruction.Even EUS-GE guided ERCP and EUS-guided gastrointestinal anastomosis for the treatment of afferent loop syndrome have been performed,giving patients more less invasive options.However,EUS-GE is still a technically challenging procedure.In order to improve EUS-GE,several techniques have been reported to improve the technical details.With EUS-GE widely performed,more data about EUS-GE’s clinical outcomes have been reported.The aim of the current review is to describe technical details updates,clinical outcomes,and adverse events of EUS-GE.

Comparison of trans-gastric vs trans-enteric(trans-duodenal or trans-jejunal)endoscopic ultrasound guided gallbladder drainage using lumen apposing metal stents

BACKGROUND Endoscopic ultrasound guided gallbladder drainage(EUS-GBD)is being increasingly used in practice(either as a bridge to cholecystectomy in high-risk patients or as destination therapy in non-surgical patients).Stents are used to create a conduit between the lumen of the gallbladder(GB)and the intestinal lumen through the gastric or enteric routes.Among the various types of stents used,cautery-enhanced lumen apposing metallic stents(LAMS)may be associated with fewer adverse events(AEs).AIM To compare the clinical success,technical success,and rate of AEs between transgastric(TG)and trans-enteric[transduodenal(TD)/transjejunal(TJ)]approach to GB drainage.Further,we analyzed whether using cautery enhanced stents during EUS-GBD impacts the above parameters.METHODS Study was registered in PROSPERO(CRD42022319019)and comprehensive literature review was conducted.Manuscripts were reviewed for the data collection:Rate of AEs,clinical success,and technical success.Random effects model was utilized for the analysis.RESULTS No statistically significant difference in clinical and technical success between the TD/TJ and TG approaches(P>0.05)were noted.There was no statistically significant difference in the rate of AEs when comparing two-arm studies only.However,when all studies were included in the analysis difference was almost significant favoring the TD/TJ approach.When comparing cautery-enhanced LAMS with non-cautery enhanced LAMS,a statistically significant difference in the rate of AEs was observed when all the studies were included,with the rate being higher in non-cautery enhanced stents(14.0%vs 37.8%;P<0.01).CONCLUSION As per our study results,TD/TJ approach appears to be associated with lower rate of adverse events and comparable efficacy when compared to the TG approach for the EUS-GBD.Additionally,use of cautery-enhanced LAMS for EUS-GBD is associated with a more favorable adverse event profile compared to cold LAMS.Though the approach chosen depends on several patient and physician factors,the above findings could help in deciding the ideal drainage route when both TG and TD/TJ approaches are feasible.

Reducing risk of transjugular intrahepatic portosystemic shunt using ultrasound guided single needle pass

Delayed liver laceration following transjugular intrahepatic portosystemic shunt (TIPS) is a serious and likely underdiagnosed complication. It is however an important complication following TIPS, which remains one of the most technically challenging interventional procedures performed. In addition to laceration, a number of complications regarding bleeding and perforation are well described following TIPS procedures. We feel the adoption of techniques such as ours and that of other authors described in the literature using an ultrasoundguided percutaneous transhepatic approach with a small caliber needle provides a safer and less traumatic procedure and should reduce complications of bleeding and almost completely eliminate the risk of liver laceration. Our procedure was successfully performed under conscious sedation rather than general anaesthesia further reducing the overall procedural risk to the patient.

Tumors and new endoscopic ultrasound-guided therapies

With the advent of linear echoendoscopes, endoscopic ultrasound (EUS) has become more operative and a new field of oncological application has been opened up. From tumor staging to tissue acquisition under EUS-guided fine-needle aspiration, new operative procedures have been developed on the principle of the EUS-guided puncture. A hybrid probe combining radiofrequency with cryotechnology is now available, to be passed through the operative channel of the echoendoscope into the tumor to create an area of ablation. EUS-guided fine-needle injection is emerging as a method to deliver anti-tumoral agents inside the tumor. Ethanol lavage, with or without paclitaxel, has been proposed for the treatment of cystic tumors in non-resectable cases and complete resolution has been recorded in up to 70%-80%. Many other chemical or biological agents have been investigated for the treatment of pancreatic adenocarcinoma: activated allogenic lymphocyte culture (Cytoimplant), a replication-deficient adenovirus vector carrying the tumor necrosis factor-α gene, or an oncolytic attenuated adenovirus (ONYX-015). The potential advantage of treatment under EUS control is the real-time imaging guidance into a deep target likethe pancreas which is extremely difficult to reach by a percutaneous approach. To date there are no randomized controlled trials to confirm the real clinical benefits of these treatments compared to standard therapy so it seems wise to reserve them only for experimental protocols approved by ethics committees.

Balloon dilator controls massive bleeding during endoscopic ultrasound-guided drainage for pancreatic pseudocyst:A case report and review of literature

Pancreatic pseudocyst(PPC), a common sequela of acute or chronic pancreatitis, was defined by the revised Atlanta classification as "a collection." Endoscopic ultrasound(EUS)-guided drainage is often considered a standard first-line therapy for patients with symptomatic PPC. This effective approach exhibits 90%-100% technical success and 85%-98% clinical success. Bleeding is a deadly adverse event associated with EUS-guided drainage procedures, and the bleeding rate ranges from 3% to 14%. Hemostasis involves conservative treatment, endoscopy, interventional radiology-guided embolization and surgery. However, few studies have reported on EUSguided drainage with massive, multiple hemorrhages related to severe pancreatogenic portal hypertension(PPH). Thus, the aim of this case report was to present a case using a balloon dilator to achieve successful hemostasis for PPH-related massive bleeding in EUSguided drainage of PPC. To our knowledge, this method has not been previously reported.

Endoscopic ultrasound guided liver biopsy for parenchymal liver disease

Liver biopsy plays an essential role in the diagnosis, evaluation and management of a vast proportion of liver diseases. Conventionally, percutaneous and transjugular approaches have been used to obtain liver biopsies. Endoscopic ultrasound guided liver biopsy(EUS-LB) has emerged as a safe and effective alternate in the past two decades. EUS-LB carries a role in evaluation of both benign and malignant diseases of the liver. It can offer higher resolution imaging of the liver and can detect smaller lesions than computed tomography scan of the abdomen or ultrasound scans with the option for doppler assistance to reduce complications. Current evidence demonstrates the superiority of EUS-LB for a targeted approach of focal lesion and there is also evidence of less sampling variability in heterogeneous parenchymal pathologies. These advantages combined with an improved safety profile had led to the rapid progress in the development of new techniques, equipment and procedures for EUS-LB. We provide a comprehensive review of EUS-LB for parenchymal liver disease.

Ultrasound-and MR-guided focused ultrasound surgery for prostate cancer

Prostate cancer(PC) is one of the most frequently diagnosed cancers in men.There are a number of treatment options for PC with a different therapeutic approach between USA and Europe.Radical prostatectomy is one of the most used therapies but focal gland therapy is an emerging approach,especially for localized tumors.In this scenario,high intensity focused ultrasound(HIFU) has been incorporated in certain medical association guidelines.HIFU has been employed for about 10 years especially for localized PC.Results are promising with a 5-year biochemical survival rate ranging from 45% to 84%.Collateral events are rare and HIFU retreatment is not common.Magnetic resonance guided focused ultrasound surgery(MRgFUS) was recently presented as a method for ablation with focused ultrasound under magnetic resonance imaging guidance.It has the advantage of improved targeting and real time temperature monitoring but only a few studies have been conducted with human patients.The aim of this review is to describe the current status of HIFU and MRgFUS in the therapy of PC.

Rapid on-site evaluation of endoscopic-ultrasound-guided fine-needle aspiration diagnosis of pancreatic masses

Endoscopic ultrasound (EUS) has become an essential tool for the study of pancreatic diseases. Specifically, EUS plays a pivotal role evaluating patients with a known or suspected pancreatic mass. In this setting, differential diagnosis remains a clinical challenge. EUS-guided fine-needle aspiration (FNA) and fine-needle biopsy (FNB) have been proven to be safe and useful tools in this setting. EUS-guided FNA and FNB, by obtaining cytological and/or histological samples, are able to diagnose pancreatic lesions with high sensitivity and specificity. In this context, several methodological features, trying to increase the diagnostic yield of EUS-guided FNA and FNB, have been evaluated. In this review, we focus on the role of rapid on-site evaluation (ROSE). From data reported in the literature, ROSE may increase diagnostic yield of EUS-FNA specimens by 10%-30%, and thus, diagnostic accuracy. However, we should point out that many recent studies have reported adequacy rates of &#x0003e; 90% without ROSE, indicating that, perhaps, at high-volume centers, ROSE may not be indispensable to achieve excellent results. The use of ROSE can be considered important during the learning curve of EUS-FNA, and also in hospital with diagnostic accuracy rates &#x0003c; 90%.

A novel technique for endoscopic ultrasound-guided biliary drainage

AIM: To describe a successful endoscopic ultrasound (EUS)-guided biliary drainage technique with high success and low complication rates. METHODS: The recorded data of consecutive patients who presented to Siriraj Gastrointestinal Endoscopy Center, Siriraj Hospital in Bangkok, Thailand for treatment of malignant obstructive jaundice but failed endoscopic retrograde cholangiopancreatography and underwent subsequent EUS-guided biliary drainage were retrospectively reviewed. The patients' baseline characteristics, clinical manifestations, procedure details, and post-procedure follow-up data were recorded and analyzed. Clinical outcomes were assessed by physical exam and standard laboratory tests. Technical success of the procedure was defined as completion of the stent insertion. Clinical success was defined as improvement of the patient's overall clinical manifestations, in terms of general well-being evidenced by physical examination, restoration of normal appetite, and adequate biliary drainage. Overall median survival time was calculated as the time from the procedure until the time of death, and survival analysis was performed by the Kaplan-Meier method. The Student's t -test and the χ 2 test were used to assess the significance of inter-group differences. RESULTS: A total of 21 cases were enrolled, a single endoscopist performed all the procedures. The mean age was 62.8 years (range: 46-84 years). The sex distribution was almost equal, including 11 women and 10 men. Patients with failed papillary cannulation (33.3%), duodenal obstruction (42.9%), failed selective cannulation (19.0%), and surgical altered anatomy (4.8%) were considered candidates for EUS-guided biliary drainage. Six patients underwent EUS-guided choledochoduodenostomy and 15 underwent EUS-guided hepaticogastrostomy. The technique using non-cauterization and no balloon dilation was performed for all cases, employing the in-house manufactured tapered tip Teflon catheter to achieve the dilation. The technical success and clinical success rates of this technique were 95.2% and 90.5%, respectively. Complications included bile leakage and pneumoperitoneum, occurred at a rate of 9.5%. None of the patients died from the procedure. One patient presented with a biloma, a major complication that was successfully treated by another endoscopic procedure. CONCLUSION: We present a highly effective EUS-guided biliary drainage technique that does not require cauterization or balloon dilation.

Endoscopic ultrasound-guided biliary intervention in patients with surgically altered anatomy

AIM: To evaluate the efficacy of endoscopic ultrasound guided biliary drainage(EUS-BD) in patients with surgically altered anatomies.METHODS: We performed a search of the MEDLINE database for studies published between 2001 to July2014 reporting on EUS-BD in patients with surgically altered anatomy using the terms "EUS drainage" and "altered anatomy". All relevant articles were accessed in full text. A manual search of the reference lists of relevant retrieved articles was also performed. Only fulltext English papers were included. Data regarding age, gender, diagnosis, method of EUS-BD and intervention, type of altered anatomy, technical success, clinical success, and complications were extracted and collected. Anatomic alterations were categorized as: group 1, Billroth Ⅰ; group 2, Billroth Ⅱ; group 4, Rouxen-Y with gastric bypass; and group 3, all other types. RESULTS: Twenty three articles identified in the literature search, three reports were from the same group with different numbers of cases. In total, 101 cases of EUS-BD in patients with altered anatomy were identified. Twenty-seven cases had no information and were excluded. Seventy four cases were included for analysis. Data of EUS-BD in patients categorized as group 1, 2 and 4 were limited with 2, 3 and 6 cases with EUS-BD done respectively. Thirty four cases with EUS-BD were reported in group 3. The pooled technical success, clinical success, and complication rates of all reports with available data were 89.18%, 91.07% and 17.5%, respectively. The results are similar to the reported outcomes of EUS-BD in general, however, with limited data of EUS-BD in patients with altered anatomy rendered it difficult to draw a firm conclusion. CONCLUSION: EUS-BD may be an option for patients with altered anatomy after a failed endoscopic-retrogradecholangiography in centers with expertise in EUS-BD procedures in a research setting.

Procedural simulation:medical student preference and value of three task trainers for ultrasound guided regional anesthesia

BACKGROUND: Ultrasound guided regional anesthesia is widely taught using task trainer models. Commercially available models are often used; however, they can be cost prohibitive. Therefore, alternative "homemade" models with similar fidelity are often used. We hypothesize that professional task trainers will be preferred over homemade models. The purpose of this study is to determine realism, durability and cleanliness of three different task trainers for ultrasound guided nerve blocks.METHODS: This was a prospective observational study using a convenience sample of medical student participants in an ultrasound guided nerve block training session on January 24 th, 2015. Participants were asked to perform simulated nerve blocks on three different task trainers including, 1 commercial and 2 homemade. A questionnaire was then given to all participants to rate their experiences both with and without the knowledge on the cost of the simulator device.RESULTS: Data was collected from 25 participants. The Blue Phantom model was found to have the highest fidelity. Initially, 10(40%) of the participants preferred the Blue Phantom model, while 10(40%) preferred the homemade gelatin model and 5(20%) preferred the homemade tofu model. After cost awareness, the majority, 18(72%) preferred the gelatin model.CONCLUSION: The Blue Phantom model was thought to have the highest fidelity, but after cost consideration the homemade gelatin model was preferred.

Technical tips for endoscopic ultrasound-guided hepaticogastrostomy

Interventional procedures using endoscopic ultrasound(EUS) have recently been developed. For biliary drainage, EUS-guided trans-luminal drainage has been reported. In this procedure, the transduodenal approach for extrahepatic bile ducts is called EUSguided choledochoduodenostomy, and the transgastric approach for intrahepatic bile ducts is called EUSguided hepaticogastrostomy(EUS-HGS). These procedures have several effects, such as internal drainage and avoiding post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis, and they are indicated for an inaccessible ampulla of Vater due to duodenal obstruction or surgical anatomy. EUS-HGS has particularly wide indications and clinical impact as an alternative biliary drainage method. In this procedure, it is necessary to dilate the fistula, and several devices and approaches have been reported. Stent selection is also important. In previous reports, the overall technical success rate was 82%(221/270), the clinical success rate was 97%(218/225), and the overall adverse event rate for EUS-HGS was 23%(62/270). Adverse events of EUS-biliary drainage are still high compared with ERCP or PTCD. EUSHGS should continue to be performed by experienced endoscopists who can use various strategies when adverse events occur.

Cavernosal nerve functionality evaluation after magnetic resonance imaging-guided transurethral ultrasound treatment of the prostate

AIM: To evaluate the feasibility of using therapeutic ultrasound as an alternative treatment option for organconfined prostate cancer. METHODS: In this study, a trans-urethral therapeutic ultrasound applicator in combination with 3T magnetic resonance imaging(MRI) guidance was used for realtime multi-planar MRI-based temperature monitoring and temperature feedback control of prostatic tissue thermal ablation in vivo. We evaluated the feasibility and safety of MRI-guided trans-urethral ultrasound to effectively and accurately ablate prostate tissue while minimizing the damage to surrounding tissues in eight canine prostates. MRI was used to plan sonications, monitor temperature changes during therapy, and to evaluate treatment outcome. Real-time temperature and thermal dose maps were calculated using the proton resonance frequency shift technique and were displayed as two-dimensional color-coded overlays on top of the anatomical images. After ultrasound treatment, an evaluation of the integrity of cavernosal nerves was performed during prostatectomy with a nerve stimulator that measured tumescence response quantitatively and indicated intact cavernous nerve functionality. Planned sonication volumes were visually correlated to MRI ablation volumes and corresponding histo-pathological sections after prostatectomy. RESULTS: A total of 16 sonications were performed in 8 canines. MR images acquired before ultrasound treatment were used to localize the prostate and to prescribe sonication targets in all canines. Temperature elevations corresponded within 1 degree of the targeted sonication angle, as well as with the width and length of the active transducer elements. The ultrasound treatment procedures were automatically interrupted when the temperature in the target zone reached 56 ℃. In all canines erectile responses were evaluated with a cavernous nerve stimulator post-treatment and showed a tumescence response after stimulation with an electric current. These results indicated intact cavernous nerve functionality. In all specimens, regions of thermal ablation were limited to areas within the prostate capsule and no damage was observed in periprostatic tissues. Additionally, a visual analysis of the ablation zones on contrast-enhanced MR images acquired post ultrasound treatment correlated excellent with the ablation zones on thermal dose maps. All of the ablation zones received a consensus score of 3(excellent) for the location and size of the correlation between the histologic ablation zone and MRI based ablation zone. During the prostatectomy and histologic examination, no damage was noted in the bladder or rectum.CONCLUSION: Trans-urethral ultrasound treatment of the prostate with MRI guidance has potential to safely, reliably, and accurately ablate prostatic regions, while minimizing the morbidities associated with conventional whole-gland resection or therapy.

Update on endoscopic ultrasound-guided liver biopsy

Endoscopic ultrasound guided liver biopsy(EUS-LB)has emerged as a minimally-invasive alternative to the traditional(percutaneous or transjugular)liver biopsy techniques for the diagnosis of liver parenchymal diseases.Potentially,EUS-LB combines the advantages of percutaneous and transjugular liver biopsy in addressing focused sampling in addition to measuring portal pressure.Additionally,EUS-LB facilitates access to both the lobes of the liver which is not considered with the traditional percutaneous liver biopsy.Multiple studies have compared EUS-LB with conventional liver biopsy and reported comparable diagnostic yield,increased acquisition of complete portal tracts,and longer specimen length as compared to the traditional approaches.EUS-LB is associated with lesser post-procedural pain and shorter recovery time,while providing lower risk of complications when compared to traditional liver biopsy.Innovations in needle types,needle sizes and suction techniques have aimed at further optimizing the EUS-LB technique.This review article updates current literature with focus on the variations in the technique and equipment used for EUS-LB,and compares EUS-LB with traditional methods of liver biopsy.

Endoscopic ultrasound guided fine needle aspiration and useful ancillary methods

The role of endoscopic ultrasound(EUS) in evaluating pancreatic pathology has been well documented from the beginning of its clinical use. High spatial resolution and the close proximity to the evaluated organs within the mediastinum and abdominal cavity allow detection of small focal lesions and precise tissue acquisition from suspected lesions within the reach of this method. Fine needle aspiration(FNA) is considered of additional value to EUS and is performed to obtain tissue diagnosis. Tissue acquisition from suspected lesions for cytological or histological analysis allows, not only the differentiation between malignant and non-malignant lesions, but, in most cases, also the accurate distinction between the various types of malignant lesions. It is well documented that the best results are achieved only if an adequate sample is obtained for further analysis, if the material is processed in an appropriate way, and if adequate ancillary methods are performed. This is a multi-step process and could be quite a challenge in some cases. In this article, we discuss the technical aspects of tissue acquisition by EUS-guided-FNA(EUS-FNA), as well as the role of an on-site cytopathologist, various means of specimen processing, and the selection of the appropriate ancillary method for providing an accurate tissue diagnosis and maximizing the yield of this method. The main goal of this review is to alert endosonographers, not only to the different possibilities of tissue acquisition, namely EUS-FNA, but also to bring to their attention the importance of proper sample processing in the evaluation of various lesions in the gastrointestinal tract and other accessible organs. All aspects of tissue acquisition(needles, suction, use of stylet, complications, etc.) have been well discussed lately. Adequate tissue samples enable comprehensive diagnoses, which answer the main clinical questions, thus enabling targeted therapy.