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Competing Interests: The authors declare that they have no conflict of interest.

Competing Interests: C. J. Lightdale: Advisory panel for Boston Scientific; independent contractor for Cook Medical; consultant for Pentax/C2. A. Ginès: consultant for Cook Endoscopy.

Competing Interests: None

Competing Interests: None

Competing Interests: None

Background: Insertion of fiducials to outline the targeted lesion allows image-guided radiotherapy, and is best achieved by endoscopic ultrasound (EUS). This study is a performance comparison of the new EUS-guided preloaded fiducial needle against Visicoil fiducials., Methods: Technical success, visibility score, procedural time, costs, and complications for patients who underwent EUS-guided fiducial placement in upper gastrointestinal malignancies were prospectively collected., Results: 60 patients with upper gastrointestinal cancers had fiducials (14 Visicoil; 46 preloaded fiducials) inserted for image-guided radiotherapy. Technical success was 100 %, with a shorter mean (standard deviation) insertion time of 0.94 minutes (0.28 minutes) vs. 5.5 minutes (1.9 minutes; P  < 0.001) and higher visibility score on fluoroscopy of 2 vs. 1.18 ( P  < 0.001) in the preloaded group. Neither group had major complications related to fiducial insertion. The cost of consumables per patient was lower in the preloaded group at US$480 (US$124) vs. US$643 (US$123; P  < 0.001)., Conclusion: Fiducial insertion for image-guided radiotherapy using the new preloaded needle is associated with 100 % technical success, shorter insertion time, and higher visibility, and is more cost-effective than the Visicoil system., Competing Interests: None., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: A forward-viewing linear (FVL) echoendoscope has been developed with the aim of overcoming some of the limitations of standard curved linear-array (CLA) echoendoscopes. There are no existing studies comparing the performance of the two echoendoscopes for endoscopic ultrasound-guided tissue acquisition (EUS-TA) of solid lesions other than subepithelial lesions., Methods: This was a prospective, multicenter, randomized trial with a noninferiority design comparing FVL vs. CLA echoendoscopes in patients with solid lesions of the gastrointestinal tract or adjacent organs. Primary outcomes were successful identification of the lesion and success of EUS-TA. Secondary outcomes were safety, sensitivity, specificity, and diagnostic accuracy of the two different scopes for EUS-TA., Results: 126 patients with solid lesions were randomly assigned to the CLA group (63 patients) or the FVL group (63 patients). The two groups were homogeneous with no differences in terms of needle type used, mean number of passes, and site of EUS-TA. No differences were observed between the FVL vs. CLA scopes in identification of the lesion (96.8 % vs. 98.4 %; P  > 0.99) and technical success of EUS-TA (92.1 % vs. 96.8 %; P  = 0.44). No adverse events occurred. Overall, diagnostic accuracy (77.8 % vs. 84.1 %), sensitivity (76.6 % vs. 84.1 %), and specificity (81.3 % vs. 84.2 %) did not differ between the two groups., Conclusions: Our results strongly suggest that the FVL echoendoscope is noninferior to the CLA scope for the detection and performance of EUS-TA in patients with solid lesions of the gastrointestinal tract and adjacent organs. In addition, the FVL scope has the same diagnostic yield, accuracy, and safety as the CLA scope., Competing Interests: Prof. Fockens is a consultant for Olympus Medical. Prof. Deviere has received research support for IRB-approved studies from Olympus Medical. Prof. Costamagna is a consultant for Olympus Medical and has received research grants from Olympus Medical., (© Georg Thieme Verlag KG Stuttgart · New York.)

Competing Interests: Reem Z. Sharaiha is a consultant for Boston Scientific and Apollo Endosurgery.

Competing Interests: Competing interests: Hiroyuke Isayama and Yousuke Nakai have financial relationships with Fujifilm Corp. in the form of research support and/or honoraria.

Background and Study Aims: The overall diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for subepithelial lesions (SELs) is suboptimal. The aim of this study was to evaluate the diagnostic accuracy, defined as the proportion of correct diagnoses, obtained using the EUS-guided fine-needle tissue acquisition (FNTA) sampling technique performed with the newly developed forward-viewing EUS scope (FV-EUS)., Patients and Methods: This was a retrospective analysis of a prospectively collected database including all consecutive patients with SELs who underwent EUS-FNTA using the FV-EUS scope from 2007 to 2011 in a tertiary referral center. All procedures were performed by a single expert endoscopist., Results: A total of 121 consecutive patients with SELs (13 in the esophagus, 96 in the stomach, 10 in the duodenum, 2 in the rectum) underwent sampling of the lesion using the FV-EUS scope. The procedure was technically feasible in all but one patient, and no complication related to EUS-FNTA occurred. Full histological assessment including immunostaining could be completed in 93.4% (113/121) of the patients. Considering neoplastic vs. non-neoplastic diseases, the sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were 92.8% (95%CI 86.3-96.8), 100% (95%CI 69.0-100%), infinity, and 0.07 (95%CI 0.04-0.14), respectively., Conclusions: EUS-FNTA performed in conjunction with the FV-EUS scope for sampling SELs of the gastrointestinal tract was safe and provided a very high diagnostic accuracy. Studies comparing FV-EUS with standard curved linear echoendoscopes are needed to clarify whether these results are due to the sampling technique or the type of scope utilized., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background and Study Aims: Accurate lymph node staging is essential for the selection of an optimal treatment in patients with upper gastrointestinal cancer. Endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) are considered to be the most accurate method for locoregional staging. Endoscopic sonoelastography (ESE) assesses the elasticity of lymph nodes and has been used to differentiate lymph nodes with promising results. The aim of this study was to evaluate the use of EUS, EUS - FNA, ESE, and ESE-strain ratio using histology as the gold standard., Patients and Methods: Patients with upper gastrointestinal cancer who were referred for EUS examination were enrolled if surgical treatment was planned and the patient had a lymph node that was accessible for EUS - FNA and EUS-guided fine-needle marking (FNM). The lymph node was classified using EUS, ESE, and ESE-strain ratio. Finally, EUS - FNA and EUS - FNM were performed. The marked lymph node was isolated during surgery for histological examination., Results: The marked lymph node was isolated for separate histological examination in 56 patients, of whom 22 (39 %) had malignant lymph nodes and 34 (61 %) had benign lymph nodes. There were no complications of EUS - FNM. The sensitivity of EUS for differentiation between malignant and benign lymph nodes was 86 % compared with 55 % - 59 % for the different ESE modalities. The specificity of EUS was 71 % compared with 82 % - 85 % using ESE modalities., Conclusion: The use of the EUS - FNM technique enabled the identification of a specific lymph node and thereby the use of histology as gold standard. ESE and ESE-strain ratio were no better than standard EUS in differentiating between malignant and benign lymph nodes in patients with resectable upper gastrointestinal cancer., (© Georg Thieme Verlag KG Stuttgart · New York.)

Our purpose was to demonstrate the use of radiofrequency spectral analysis to distinguish between benign and malignant lymph nodes with data obtained using electronic array echo endoscopes, as we have done previously using mechanical echo endoscopes. In a prospective study, images were obtained from eight patients with benign-appearing lymph nodes and 11 with malignant lymph nodes, as verified by fine-needle aspiration. Midband fit, slope, intercept, correlation coefficient, and root-mean-square (RMS) deviation from a linear regression of the calibrated power spectra were determined and compared between the groups. Significant differences were observable for mean midband fit, intercept, and RMS deviation (t test P < 0.05). For benign (n = 16) vs. malignant (n = 12) lymph nodes, midband fit and RMS deviation provided classification with 89 % accuracy and area under receiver operating characteristic (ROC) curve of 0.95 based on linear discriminant analysis. We concluded that the mean spectral parameters of the backscattered signals from electronic array echo endoscopy can provide a noninvasive method to quantitatively discriminate between benign and malignant lymph nodes., (© Georg Thieme Verlag KG Stuttgart · New York.)

Presentations at this year's Digestive Disease Week (DWW; 7-10 May, 2011; Chicago, Illinois, USA) reflected a very active year for endoscopic ultrasound (EUS). There were numerous abstracts on EUS-guided fine-needle aspiration (FNA) and core biopsy to improve tissue acquisition, improve diagnostic accuracy, and indeed go beyond routine cytology and tissue diagnosis. EUS-guided therapy including drainage, anastomoses, injection of therapeutic agents, and ablation were other common themes with a lot of new information presented, much of which was obtained from randomized trials. This review discusses in detail some of the abstracts that followed a common theme. Additional interesting abstracts on this topic are listed at the end of the review., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background and Study Aim: A prototype forward-viewing instrument has been developed for therapeutic endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA). We had the opportunity to use this forward-viewing echo endoscope and to study its clinical usefulness, mainly for diagnostic EUS-FNA., Patients and Methods: The prototype forward-viewing echo endoscope was used for 15 months between November 2006 and March 2010, in a study group comprising 47 consecutive patients. Diagnostic EUS-FNA was done in 38 patients and the diagnostic accuracy of the forward-viewing device was compared with that from an oblique-viewing echo endoscope in reference patients who were matched by disease and puncture route. Therapeutic EUS was done in nine patients (pseudocyst drainage in six; celiac ganglia neurolysis, biliary drainage, and pancreatic duct drainage in one each)., Results: Diagnostic EUS-FNA provided a correct diagnosis in 97.4 % (37/38 patients), which was not significantly different from the 94.7 % (36/38) in the reference patients. Lesions considered difficult to access with an oblique-viewing scope, such as those located at the fornix, or the head of the pancreas, or associated with strictures, were easily punctured, as were those located at the body or tail of the pancreas or at the porta hepatis. Treatment was successful in all nine patients who underwent therapeutic EUS procedures. None of the 47 patients had any complications., Conclusions: A forward-viewing echo endoscope that allows target sites to be punctured more perpendicularly with minimal effort, can be used for diagnostic EUS-FNA and this may be advantageous, depending on the site of target lesions., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background and Study Aims: The effectiveness of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) with (S+) and without (S-) a stylet has never been compared. We prospectively compared the yield for malignancy and sample quality of S+ and S- EUS-FNA., Patients and Methods: S+ or S- EUS-FNA was performed on consecutive solid lesions, with a 22-gauge needle, with systematic assignment of S+ or S- passes in a 1 : 2 ratio. Slides were read by a single, blinded cytologist and were rated for bloodiness, adequacy, and presence of malignancy. The yield for malignancy was compared only in lesions in which equal numbers of S+ and S- passes were performed., Results: A total of 309 passes (mean 2.3 passes/lesion, range 1-6, 82% adequate, 38% S+, 62% S-) were performed on 135 lesions (63% malignant, 42% nodes, 58% masses [79% pancreatic]) in 111 patients (mean age 62.9 years, range 30-86). In 46 lesions where an equal number (53 S+ and 53 S-) of passes was performed, there was no difference in the proportion of cases in which S+ FNA was "equal to or better than" S- FNA ([S+] 89% vs. [S-] 87%; P>0.05). The results of the two methods agreed in 80% cases (kappa 0.60). The sensitivities for malignancy were: S+ 87% vs. S- 83%, P>0.05. Specificities were 100%. Sample adequacy was significantly lower in S+ passes (75% vs. 87%, P=0.013), and sample bloodiness was significantly higher (75% vs. 52%, P<0.0001)., Conclusions: Use of the stylet with EUS-FNA does not increase the yield for malignancy and is associated with poorer sample quality. The value of the stylet for EUS-FNA is questionable and requires further investigation., (© Georg Thieme Verlag KG Stuttgart · New York.)

A reliable method of transvaginal access is needed for natural orifice transluminal endoscopic surgery. We introduce a new culdotomy procedure, using a technique for the creation of space in the cul-de-sac, transvaginal ultrasound, and a newly developed umbrella Hakko needle. An artificially developed, saline-containing space in the cul-de-sac was punctured by an umbrella Hakko needle from the vagina under the guidance of ultrasound. The vaginal walls on both sides of the needle were incised with an electric scalpel. In five cases with benign gynecological tumors, culdotomy was successfully performed. Operating time was less than 10 minutes and blood loss was less than 10 mL. There were no culdotomy-associated complications. This procedure, named Culdotomy FourS Two U, is a simple, safe, and reliable method for entry into the cul-de-sac in transvaginal gynecological surgeries and may have future applications in transluminal endoscopic surgery through the vagina.

Background and Study Aims: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is now performed routinely in many advanced endoscopy centers and has enhanced the ability to diagnose pancreatic masses. However, there is uncertainty about which needle size is optimal for EUS-FNA of pancreatic masses. We aimed to evaluate the performance of the 22-gauge and 25-gauge needles in obtaining cytologic diagnosis of pancreatic masses., Methods: All cases that were referred for EUS-FNA for pancreatic masses between February 2001 and June 2007 were reviewed, and patients who underwent EUS-FNA using the 22-gauge and 25-gauge needle system were identified. In patients who underwent surgery, operative histopathological findings were compared with the cytopathological findings from EUS-FNA., Results: A total of 842 patients with pancreatic masses detected on computed tomography (CT) and/or magnetic resonance imaging (MRI) and confirmed by EUS underwent EUS-FNA with the 22-gauge needle (n = 540) or the 25-gauge needle (n = 302). Results of EUS-FNA cytology findings were compared with the gold standard of surgical histopathological findings or long-term clinical follow-up. The sensitivity, specificity, PPV, and NPV of FNA were respectively 84%, 100%, 100%, and 73% [corrected] for the 22-gauge needle compared with 92%, 97%, 98%, and 87%, [corrected] respectively for the 25-gauge needle. No complications were noted in the 25-gauge needle group, compared with pancreatitis in 2% of the 22-gauge needle group., Conclusions: This retrospective comparative study shows that EUS-FNA with a 25-gauge needle system is a safe and reliable method for tissue sampling in pancreatic masses. The system is more sensitive and has a slightly [corrected] higher NPV than the standard 22-gauge needle. Our study suggests that perhaps the smaller caliber FNA needle causes less trauma during EUS-FNA and hence less complications. Further studies including randomized trials are needed.

Background and Study Aims: Endoscopic ultrasonography (EUS) has been established as a valuable diagnostic tool for the detection of bile duct stones (BDS). The recently introduced extraductal endoscopic ultrasonography (EDUS) using miniprobes has the advantage that it can be performed with a duodenoscope, and if therapeutic interventions become necessary, there is no need to change the scope., Patients and Methods: Consecutive patients with acute biliary pain and a dilated bile duct and/or elevated liver function tests, in whom the origin of biliary obstruction could not be identified by US and CT, were enrolled. The patients were investigated with a linear-array echoendoscope, and an additional transduodenal EDUS examination was performed with a 12-MHz miniprobe via the instrumentation channel of the echoendoscope. The presence or absence of BDS was afterwards evaluated by endoscopic retrograde cholangiopancreatography (ERCP)/sphincterotomy (EST) and by instrumental bile duct exploration (in the case of a positive EUS/EDUS finding), or by magnetic resonance cholangiopancreatography (MRCP) and ERCP with additional clinical follow-up (in the case of negative findings on EUS/EDUS)., Results: One hundred and fifty-five patients (55 +/- 12 years old, 98 female) were enrolled. In six cases, the distal bile duct could not be successfully visualized by EDUS, whereas with EUS visualization failed in only one patient ( P = 0.13). Choledocholithiasis was proven in 75 cases (48 %). The diagnostic accuracy of EUS for the detection of BDS (sensitivity 92 %, specificity 100 %, PPV 1.0, NPV 0.93, accuracy 95 %) was comparable to that of EDUS (sensitivity 90 %, specificity 98 %, PPV 0.99, NPV 0.93, accuracy 91 %, P = 0.17 vs. EUS)., Conclusions: In patients at intermediate risk of BDS it seems to be justified to perform EDUS instead of EUS, and to proceed with ERCP and EST immediately when findings are positive.

Background and Study Aims: The high-frequency endosonography miniprobe has been advocated prior to endoscopic treatment of superficial esophageal neoplasm. We conducted a retrospective study, which summarized our clinical experience with various miniprobe techniques in the assessment of early squamous cell carcinoma (SCC) and superficial adenocarcinoma on Barrett's mucosa (SAB)., Patients and Methods: A total of 106 superficial and naive esophageal lesions were included in this series (52 SAB, 54 SCC). The results of the miniprobe staging were compared with pathology in order to determine the accuracy of this technique in differentiating mucosal from submucosal infiltration. Secondary aims were a comparison between the frequencies (20- vs. 30-MHz) and coupling methods (water-filled lumen vs. balloon-sheathed catheter) used., Results: Overall accuracy, sensitivity, and specificity to differentiate T1sm from T1 m tumors were 73.5 %, 62 %, and 76.5 %, respectively. Overdiagnosis occurred in 18.6 % of the lesions. No statistically significant difference was found in the accuracy of the miniprobe staging between the two lesion types (SCC and SAB) ( P = 0.65), and results were significantly poorer in the distal part of the esophagus ( P = 0.00039). No significant difference was found between the two frequencies ( P = 0.51). Water-filled lumen proved to be superior to the balloon-sheathed catheter ( P = 0.015)., Conclusion: High-frequency miniprobe examination has a limited accuracy in the detection of submucosal invasion in early esophageal cancer. Further improvements in acoustic coupling and ultrasound technique are required to improve the miniprobe accuracy before its implementation into clinical routine.

Background and Study Aims: The need for repair of endoscopic ultrasound (EUS) equipment appears to be frequent and expensive. To better quantify the costs associated with echo endoscope failure, a survey of endosonographers was carried out., Methods: A survey questionnaire concerning echo endoscope damage and repair and consequences of echo endoscope downtime over a 12-month period was sent to members of the American Society of Gastrointestinal Endoscopy who had cited an interest in EUS., Results: Responses were received from 56 of 138 institutions where EUS was carried out (41 %). A median of 325 EUS procedures had been carried out in the past year and a median of two endosonographers were employed who used an average of three echo endoscopes. Two-thirds of institutions trained fellows. A total of 225 repairs were reported for leaks (47 %), mechanical failures (33 %), images or optics difficulties (26 %), or other problems (1 %). Mechanical radial-scanning echo endoscopes tended to break, on average, after 68 procedures, while curved linear-array echo endoscopes failed after an average of 107 procedures. Echo endoscope failures led to rescheduling of procedures at three-quarters of institutions. Institutions paid an average of $ 10 534 over 12 months for echo endoscope repairs. The average repair cost per procedure was $ 41. There was an inverse relationship between quantity of procedures and the per-procedure repair rate ( P < 0.05)., Conclusions: Direct and indirect costs of echo endoscope repairs are significant. Instrument failures are multifactorial; however instrument complexity, instrument age, and institutional inexperience may contribute to repair costs.

Background and Study Aims: The purpose of this study was to evaluate the clinical efficacy of endosonographically guided transrectal aspiration and drainage by plastic stent of deep pelvic abscesses, using a therapeutic echo endoscope device., Patients and Methods: Between September 2000 and June 2001, 12 patients (nine men, three women, mean age 67 years) were treated for a perirectal or a pelvic abscess using an endoscopic ultrasound (EUS) technique. The drainage of these fluid collections was performed under EUS guidance, using therapeutic EUS scopes with a large working channel., Results: No major complication occurred during this study. Transrectal stent insertion succeeded in nine patients. In three patients, only aspiration was possible. Among the nine patients in whom a stent was successfully introduced into the fluid collection, complete drainage without relapse was achieved in eight patients (mean follow-up 10.6 months, range 6-14 months). The stent was removed endoscopically after 3 to 6 months. Drainage was incomplete in one patient (with a large abscess, diameter > 8 cm), who subsequently underwent surgical drainage. However, two out of the three patients in whom aspiration alone was performed developed a recurrence of the abscess and required surgical treatment., Conclusion: EUS-guided drainage of deep pelvic abscesses could offer an alternative treatment to surgery in the management of these postoperative complications.

This review again uses a practical arrangement of the topics of endoscopic ultrasonography (EUS) into clinical categories rather than single diseases. The clinical categories include established indications, such as staging of gastrointestinal tract cancers, differential diagnosis of submucosal tumors, evaluation of solid and cystic pancreatic masses, detection of lymph nodes, evaluation of the biliary tree, and fine-needle aspiration (FNA). In addition to established indications, surgical and investigational techniques are presented, such as fine-needle therapeutic procedures and methods of studying portal hypertension and hepatic, abdominal, and retroperitoneal masses. This year, the new techniques and instruments presented have not included new probes or endoscopes, as these have already gained wide application in published papers and clinical practice. However, new techniques capable of facilitating the use of existing equipment are discussed, such as computer-aided EUS image analysis. Finally, some fascinating studies investigated outcomes with EUS and the cost-effectiveness of the method - stimulating both endosonographers and non-endosonographers to think about current practices and ways of improving them.

Background and Study Aims: Endoscopic ultrasound imaging of mediastinum, gastrointestinal tract and pancreas, and endoscopic ultrasound-guided fine-needle aspiration of suspicious lesions, have now been available for several years. Although many papers have been published on endoscopic ultrasonography, a comprehensive overview of the subject matter presented has not yet been carried out. An extensive survey of the literature on endoscopic ultrasonography since its inception in the 1980 s was conducted in this study; key points are summarized., Methods: A computer-based PubMed search system was used to retrieve all available abstracts pertaining to endoscopic ultrasound from 1980 to the present. Data were collected concerning the impact factor, the various EUS instruments and fine-needle aspiration biopsy techniques used, and the subject matter, as well as the journals publishing the abstracts., Results: A total of 1259 articles were published in 65 journals: 440 (35 %) Western European studies, 404 (32 %) American studies, and 321 (26 %) Japanese studies were retrieved. The total and average impact factor per paper was highest for American papers, followed by European papers and Japanese papers. Forty-seven percent of the papers were published in Gastrointestinal Endoscopy and Endoscopy. The most frequently discussed topics concerned the staging of various malignancies, including esophageal, gastric, pancreatic, and colorectal cancer. The average sample size per paper was in the range 25 - 50. The various types of study included retrospective inquiries (25 %), reviews (24 %), prospective studies (17 %), and case reports (15 %)., Conclusions: Over the course of the past 20 years, there has been a progressive increase in the number of publications pertaining to endoscopic ultrasonography. Large-scale prospective studies are now needed to validate earlier reports. In addition, the diagnostic and therapeutic role of endoscopic ultrasound needs to be more widely publicized among physicians in all health-care fields, so that appropriate patients may be referred.

Background and Study Aims: In patients with low-grade gastric MALT lymphoma, conventional endoscopic ultrasonography (EUS) is considered to be the most accurate modality for locoregional staging. The aim of this study was to evaluate the diagnostic role of ultrasonic miniprobes as part of routine clinical staging., Patients and Methods: A total of 39 patients who were histologically diagnosed with low-grade MALT lymphoma were reviewed retrospectively before treatment (n = 15) and during follow-up (n = 24). Assessment of tumor penetration into the gastric wall was based on the TNM system. Pathological lymph-node involvement was suggested by the presence of inhomogeneous hypoechoic echo patterns, with clearly demarcated borders. All examinations were carried out using a mechanical miniprobe (Olympus; diameter 2.4 mm, 12 MHz) introduced through the working channel of the endoscope. Ultrasonic miniprobe findings were compared with conventional EUS data and histology., Results: Using pretreatment endoscopic ultrasonography, gastric lymphomas presented endoscopically with an ulcer (in five of 15 patients) or a diffuse infiltrative pattern (ten of 15 patients). The ultrasonic miniprobe identified a T1 lesion in 53 % (T2, 33 %) and EUS in 60 % (T2, 20 %) of cases. Pathological lymph-node involvement in T1-T2 lesions was diagnosed with the ultrasonic miniprobe in 53 % of cases and with EUS in 60 %. Using endoscopic ultrasonography during the follow-up period, in patients with normal miniprobe ultrasonography (n = 15), the histological examination confirmed a complete remission in all patients. Hypoechoic thickening of the mucosa or submucosa, or both, was seen in nine patients. Endoscopic biopsies in four of these nine patients revealed recurrent lymphoma., Conclusions: The ultrasonic miniprobe can be recommended as part of routine care in patients with gastric MALT lymphoma, both initially and during the follow-up period. The clinical significance of ultrasonic miniprobe examinations is that they can be performed as a single-step procedure during diagnostic endoscopy.

Background and Study Aims: Recently, it was reported that focal submucosal invasive colorectal cancer could be treated by polypectomy or endoscopic mucosal resection (EMR) because of the rarity of lymph-node metastasis. Our objective was to examine the accuracy and efficacy of a 15-MHz ultrasound miniprobe in the preoperative evaluation of the degree of submucosal invasion in colorectal cancer., Patients and Methods: A total of 35 patients with submucosal invasive colorectal cancer who underwent ultrasonography with a miniprobe were studied prospectively. The results of this imaging were compared with the histologic findings in resected specimens., Results: Although the accuracy of the miniprobe in categorizing submucosal invasion into three subclasses (SM1, invasion limited to the upper third; SM2, limited to the middle third; SM3, limited to the lower third) was low (37.1%; 13/35), the accuracy in differentiation between < or = SMI (M and SMI) and > or = SM2 (SM2, SM3, MP, and S) was 85.7 % (30/35)., Conclusions: The miniprobe can be useful for therapeutic decision-making in submucosal invasive colorectal cancer.

Background and Study Aims: Although it is time-consuming to measure the volume of lesions using three-dimensional endoscopic ultrasonography (3D-EUS), the technique is suitable for tissue characterization, as it allows images of multiple areas to be obtained simultaneously in uniform conditions. The present study tested automatic volume measurement using tissue characterization based on 3D-EUS., Materials and Methods: Nine polygonal sections of resected spleen (volume 0.66 +/- 0.19 cm3) were immersed in water, and 40 radial 3D-EUS images were obtained. For tissue characterization, the methods of co-occurrence matrix and gray-level difference and discriminant analysis were used. Each spleen section was also measured using 3D-EUS. The volume of tissue identified as spleen using tissue characterization and the volume calculated on the basis of the 3D-EUS images were both compared with the actual volume measured beforehand. Measurements using tissue characterization and 3D-EUS were carried out for every third image. In three clinical cases of cancer the volume of the lesion was measured using tissue characterization and 3D-EUS., Results: The mean volume of the nine splenic sections estimated using tissue characterization was 1.2 +/- 0.41 cm3 (mean +/- SD), while the mean volume estimated with 3D-EUS imaging was 1.1 +/- 0.30 cm3 (mean +/- SD). The volumes measured using tissue characterization were on average 13% larger than those obtained with 3D-EUS. Linear regression analysis showed a high degree of correlation between the two sets of measurements (r=0.97, P<0.00005), and also showed a high correlation between the volumes obtained using tissue characterization and the actual volume (r=0.93, P<0.0005). However, the volumes calculated using 3D-EUS images were larger than the actual volume (61% on average), and the volumes estimated using tissue characterization were also greater than the actual volume. The overestimation reflected the fact that measurement was only carried out in every third 3D-EUS image. In the clinical cases, the mean value for "true" tumor tissue as determined on EUS imaging represented 73% of the volume interpreted as cancer using tissue characterization., Conclusions: There was a good correlation between the volume measured with 3D-EUS and the volume obtained using tissue characterization. The tissue characterization volumes were only relatively slightly larger than the volumes measured using 3D-EUS, suggesting that there may be some promise for this application of tissue characterization.

Background: Endoscopic ultrasonography (EUS) has become the investigation of choice for the evaluation of the mediastinum. Lung and mediastinum are amongst the common sites of metastases from renal cell cancer (RCC). We diagnosed metastatic RCC in mediastinal lymph nodes by EUS-guided fine-needle aspiration (FNA) cytology., Methods: A total of 111 patients with mediastinal lymph nodes had undergone EUS-FNA using a linear array echo endoscope and a 170 cm, 22 G GIP needle consecutively. Smears were prepared, air-dried, and sent to an independent cytologist., Results: Seven patients (all males, mean age 64.8 years, range 45-72) were diagnosed cytologically to have metastatic RCC. Three patients had been diagnosed with RCC in the past (2, 7, and 17 years ago) while in the others, this was primarily diagnosed on the basis of EUS-FNA. The EUS features of these mediastinal RCC metastases include irregular lesions with inhomogenous echotexture, measuring 2.8 cm (median; range 1.0-4.5) located predominantly in the posterior mediastinum., Conclusion: EUS-FNA diagnosis of metastatic RCC is safe and feasible. It is especially useful in the evaluation of the mediastinum for suspected metastases. Cytology examination results in combination with clinical features could suggest the site of origin of the primary, assisting in further management.

Background and Study Aims: We have previously demonstrated that an ultrasonic tactile sensor (UTS) could be used to distinguish between mucosal and submucosal cancer in surgically resected specimens, by providing a measurement of tissue stiffness which could be less prone to subjective errors. In the current study, we evaluated the potential of a newly developed, thin UTS to differentiate in vivo between mucosal and submucosal invasion during clinical endoscopic examination., Patients and Methods: Between March and July 1997, 15 patients with esophageal cancer who were not receiving special treatment, underwent preoperative UTS examination during endoscopy. The thin UTS probe was inserted through the biopsy channel of the endoscope. A transparent cap was placed on the distal end of the endoscope in order to facilitate vertical placement of the probe on the tumor., Results: Although the probe used in this study was a prototype, the results of the current in vivo study were in agreement with our previous in vitro study on surgically resected specimens. The mean delta(f) value of the mucosal cancers, which means the magnitude of the frequency shift recorded by the UTS, was -5356.23 Hz, and the corresponding value for submucosal cancers was -4126.56 Hz; this difference was significant., Conclusion: The UTS is potentially an essential tool for preoperative evaluation of esophageal cancers. The ability to differentiate between mucosal and submucosal cancers is important because of the differences in surgical management of these tumors, i.e. endoscopic mucosal resection or conventional open esophagectomy.

Background and Study Aims: Endosonographic staging of esophageal carcinoma may be limited by non-traversable tumor stenoses. Dilation of malignant esophageal strictures carries a significant risk of esophageal perforation. We therefore evaluated the use of ultrasonic miniprobes in the staging of stenotic esophageal carcinoma compared with conventional endoscopic ultrasound., Patients and Methods: In a blinded, prospective study, which included histopathological evaluation, 53 consecutive patients (43 male, 10 female, mean age 61 years) with stenosing esophageal carcinomas were examined preoperatively. Endosonography was done using the optical GF-UM3 echo endoscope. If tumor strictures were not traversable with this instrument, a blind esophagoprobe, the MH-908 was used for endosonography. Miniprobe sonography (MPS) was done during esophagoscopy in all patients. The various imaging modalities were assessed in terms of complete tumor traversability and correct tumor staging. Every patient underwent surgical tumor resection., Results: MPS of the esophagus and proximal parts of the stomach was possible in all 53 patients without prior dilation of tumor stenoses. Endosonography with the GF-UM3 instrument was precluded in 23 patients (43.4%) while in 20 of the latter patients the MH 908 esophagoprobe could be passed through tumor stenoses. The overall accuracy rates for depth of tumor infiltration (T) staging were: 62% (31/50) for endosonography (GF-UM3 plus esophagoprobe) and 86.8% (46/53) for MPS. The accuracy rates for T staging in tumors traversable both with the GF-UM3 echo endoscope and with miniprobes were 56.7% (17/30) for GF-UM3 and 80% (24/30) for MPS. The accuracy rates for T staging in tumors traversable only with the MH-908 esophagoprobe and with miniprobes were 70% (14/20) for the MH-908 and 95% (19/20) for MPS. With regard to the presence or absence of peri-esophageal metastatic lymph nodes (N staging), the accuracy rates were 83% (25/30) for MPS and 70% (21/30) for the GF-UM3, and 80% (16/20) for MPS and 70% (14/20) for the MH-908., Conclusion: Compared with conventional endosonography using 7.5-MHz large diameter instruments, MPS enables: a) safe passage through high-grade malignant esophageal strictures, achieving b) higher accuracy rates for T staging, and c) similar rates for N staging. The use of MPS can also represent an improvement in the comfort and safety of patients. Moreover, miniprobe sonography is highly cost-effective compared with conventional endosonography. Thus, MPS appears to be a valuable addition to the armamentarium for staging esophageal carcinoma.

We report here the first case of a one-step endosonography(EUS)-guided pseudocyst drainage. A prototype large channel curved array echo endoscope (Pentax FG-38 UX) and a prototype delivery system for placement of an endoprosthesis was used for the procedure. The delivery system (GIP MedicinTechnik GmbH/Medi-Globe Corporation) consists of a handle part with a piston, a metal ring sheath, a plastic catheter with a diathermy needle and a double pigtail endoprosthesis (8.5 Fr). When mounted on the endoscope the endoprosthesis can be advanced out of the distal end of the endoscope. The introduction of the stent as well as the stent release can be monitored entirely by ultrasound. The procedure was tested in a 76-year-old woman with a pseudocyst measuring 60 mm in diameter located in the tail of the pancreas. The procedure was well tolerated by the patient, and there were no procedural complications. The advantage of a large channel echo endoscope and our new prototype delivery system is that the endoprosthesis can be inserted in to a pancreatic cyst guided exclusively by EUS without exchange of endoscopes, catheters or guide wires. Further studies are warranted.