Prospective evaluation of an over-the-wire catheter US probe

Diagnosis of Cholangiocarcinoma

Cholangiocarcinoma (CCA), a tumor of the bile duct epithelium, is increasing in incidence. CCA remains a highly fatal malignancy because early diagnosis is difficult. Based on its anatomical location, CCA can be categorized into the following three groups: perihilar, intrahepatic, and extrahepatic. Patients with CCA complain of asymptomatic jaundice, weight loss, and right upper quadrant abdominal discomfort. Imaging modalities, including transabdominal ultrasound, computed tomography, and magnetic resonance imaging, play an important role in detecting tumors as well as guiding biopsy procedures and staging workups in CCA. Characteristically, extrahepatic CCA shows abrupt changes in ductal diameter with upstream ductal dilation. Endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) are recommended as the next step in the evaluation of extrahepatic CCA. Tissue is obtained through EUS-FNA or ERCP (biopsy, brush cytology), and therapeutic intervention (such as stent insertion) is performed with ERCP. Moreover, several serum tumor markers (carbohydrate antigen 19-9 and carcinoembryonic antigen) can be useful in diagnosing CCA in some patients.

Miniprobe Endoscopic Sonography for Gastrointestinal Tract Assessment: A Case Series of 1451 Procedures

Conventional endoscopic sonography has allowed precise diagnostics without disturbances, and miniprobes can be easily introduced through the biopsy channel of the endoscope. Miniprobe endoscopic sonography has many benefits compared with conventional endoscopic sonography. Although there are well-known indications for miniprobe endoscopic sonography in endoscopic digestive tract assessment, there is still a need for this method to be widely spread among physicians and commonly used by most endoscopists. The aim of this series was to describe a multicenter retrospective experience with 1451 procedures using miniprobes, presenting examples and the applicability and usefulness of this technology in the daily activities of an endoscopy department.

Intraductal Ultrasonography without Radiocontrast Cholangiogramin Patients with Extrahepatic Biliary Disease

BACKGROUND/AIMS

Intraductal ultrasonography (IDUS) has been performed as an adjunct to endoscopic retrograde cholangiography (ERC) during radiocontrast cholangiography (RC). Radiation exposure during RC poses a health risk to both patients and examiners. We evaluated the feasibility of IDUS without RC in various extrahepatic biliary diseases.

METHODS

IDUS was performed with the insertion of an IDUS probe from the papilla of Vater to the confluent portion of the common hepatic duct without fluoroscopy. The technical success rate and procedure-related complications were evaluated retrospectively.

RESULTS

Wire-guided IDUS without RC was performed in 105 patients. The mean age was 66.5 years, and 50 (47.6%) were male. The IDUS diagnoses included choledocholithiasis (73, 69.5%), benign biliary stricture (11, 10.5%), choledocholithiasis with biliary pancreatitis (9, 8.6%), bile duct cancer (5, 4.8%), pancreatic cancer (1, 0.9%), and others (6, 5.7%). After IDUS, 66 (62.8%) underwent stone removal, 19 (18.1%) underwent biliary drainage, and 7 (6.6%) underwent brush cytology and biopsy. No significant complications such as perforation or severe pancreatitis occurred.

CONCLUSIONS

IDUS without RC was a feasible and safe approach in patients with various extrahepatic biliary diseases. We anticipate a potentially important role of IDUS in various ERC procedures because it lacks the hazards of RC.

Role of Balloon-Sheathed Intraductal Ultrasonography for Patients with Extensive Pneumobilia

Intraductal ultrasonography (IDUS) is one of the most useful diagnostic tools for various extrahepatic biliary diseases. However, conventional IDUS has some limitations in providing accurate cross-sectional imaging of the bile duct in patients with extensive pneumobilia. Using a balloon-sheathed catheter, the US system (balloon-sheathed IDUS) can overcome these limitations. Sixteen patients underwent balloon-sheathed IDUS during endoscopic retrograde cholangiography. The balloon-sheathed IDUS was inserted via a transpapillary route when visualization of the bile duct with conventional IDUS was distorted by extensive pneumobilia. The patient group had a mean age of 65.5 years, and 56.3% (9/16) were male. The balloon-sheathed IDUS permitted successful visualization of the bile duct in all patients, regardless of the extent of pneumobilia. Using this system, remnant common bile duct stones were detected in five patients (31.3%), and cholangiocarcinoma was detected in one patient (6.3%). The balloon-sheath IDUS aided in stone sweeping. No significant complications, including bleeding, perforation, or pancreatitis, occurred in any of the patients. The balloon-sheathed catheter US system was useful and safe for biliary IDUS in patients with extensive pneumobilia.

Biliary strictures: diagnostic considerations and approach

Biliary strictures present a diagnostic challenge, especially when no etiology can be ascertained after laboratory evaluation, abdominal imaging and endoscopic retrograde cholangiopancreatography (ERCP) sampling. These strictures were traditionally classified as indeterminate strictures, although with advances in endoscopic techniques and better understanding of hepato-biliary pathology, more are being correctly diagnosed. The implications of missing a malignancy in patients with biliary strictures—and hence delaying surgery—are grave but a significant number of patients (up to 20%) undergoing surgery for suspected biliary malignancy can have benign pathology. The diagnostic approach to these patients involves detailed history and physical examination and depends on the presence or absence of jaundice, level of obstruction, and presence or absence of a mass lesion. While abdominal imaging helps to find the level of obstruction and provides a ‘road map' for further endoscopic investigations, tissue diagnosis is usually needed to make decisions on management. Initially ERCP was the only modality to investigate these strictures but now, with the development of endoscopic ultrasound with fine needle aspiration and the availability of newer techniques such as intraductal ultrasound, single-operator cholangioscopy and confocal laser endomicroscopy, the diagnostic approach to biliary strictures has changed significantly. In this review, we will focus on the decision-making process for patients with biliary strictures and discuss the key decision points that should dictate further diagnostic investigations at each step.

Current endoscopic approach to indeterminate biliary strictures

Biliary strictures are considered indeterminate when basic work-up, including transabdominal imaging and endoscopic retrograde cholangiopancreatography with routine cytologic brushing, are non-diagnostic. Indeterminate biliary strictures can easily be mischaracterized which may dramatically affect patient’s outcome. Early and accurate diagnosis of malignancy impacts not only a patient’s candidacy for surgery, but also potential timely targeted chemotherapies. A significant portion of patients with indeterminate biliary strictures have benign disease and accurate diagnosis is, thus, paramount to avoid unnecessary surgery. Current sampling strategies have suboptimal accuracy for the diagnosis of malignancy. Emerging data on other diagnostic modalities, such as ancillary cytology techniques, single operator cholangioscopy, and endoscopic ultrasonography-guided fine needle aspiration, revealed promising results with much improved sensitivity.

New options of cholangioscopy

In the evaluation of biliary diseases, cholangioscopy is considered as complementary procedure to radiographic imaging. Direct visualization of the bile duct is the premier advantage of cholangioscopy over indirect imaging techniques. However, cholangioscopy has not gained wide acceptance because of several technical limitations such as scope fragility, impaired steerability, limited irrigation, and suction capabilities, as well as the need for two experienced endoscopists. Recent innovations such as the implementation of electronic video cholangioscopes and the development of single-operator systems facilitate the procedure, and promise to increase the diagnostic and therapeutic yield of cholangioscopy.

Clinical application of intraductal ultrasound during endoscopic retrograde cholangiopancreatography

Intraductal ultrasound (IDUS) used during endoscopic retrograde cholangiopancreatography (ERCP) can facilitate reliable evaluation of biliary and pancreatic disorders. The smaller diameter, flexibility, and the image quality offered by IDUS devices makes them ideal for evaluating a variety of difficult biliary and pancreatic diseases, especially in undefined strictures, luminal filling defects, and ampullary neoplasms. This article examines the numerous possible roles for IDUS in the evaluation of biliary and pancreatic conditions, as well as in ampullary neoplasms. IDUS is a simple, easy to learn, and safe technique that should be considered an integral tool in the therapeutic endoscopist's armamentarium.

Are there roles for intraductal US and saline solution irrigation in ensuring complete clearance of common bile duct stones?

BACKGROUND

Persistent small common bile duct (CBD) stones after endoscopic sphincterotomy (EST) and stone extraction may be a nidus for stone growth and could be detected by intraductal US (IDUS). CBD saline solution irrigation may flush out residual stones.

OBJECTIVES

Our purpose was to determine the frequency of residual CBD stones after EST and basket/balloon extraction by using IDUS and to assess the effectiveness of saline solution irrigation in clearing remnant CBD stones.

DESIGN

Prospective study.

SETTING

General Hospital Singapore.

PATIENTS

Seventy patients (mean age 62 years, 51% male) were recruited.

INTERVENTIONS

In the presence of CBD stones, EST and stone extraction were performed, followed by IDUS. If residual stones were detected, a catheter was inserted into the proximal CBD, saline solution irrigation performed, and IDUS repeated.

MAIN OUTCOME MEASUREMENTS

(1) The frequency of residual stones detected by IDUS after EST and basket/balloon extraction and (2) the effect of saline solution irrigation in clearing residual CBD stones.

RESULTS

Cholangiogram showed CBD stones in 38 of 70 patients (median 1 [range 1-5], mean size 7.6 mm [range 3.0-12.0 mm]). IDUS showed CBD stones in 32 of 32 with normal cholangiogram (median 2 [range 1-8], mean size 2.6 mm [range 0.9-7.2 mm]). After EST and stone extraction, IDUS showed persistent stones in 28 of 70 (median: 2 [range 1-5], mean size 2.2 mm [range 1.1-4.6 mm]). The CBD was irrigated with a mean of 48 mL of saline solution. Repeat IDUS showed persistent CBD stones in 2 of 70, and these were flushed out by further saline solution irrigation.

LIMITATIONS

Single-center study.

CONCLUSION

IDUS detected small residual CBD stones that persisted after EST and basket/balloon extraction. Saline solution irrigation appeared useful in clearing residual small stones.

Clinical utility of intraductal US to decrease early recurrence rate of common bile duct stones after endoscopic papillotomy

BACKGROUND AND AIM

The aim of the present study was to determine whether additional intraductal ultrasound (IDUS) to confirm complete stone clearance decreases the recurrence rate of common bile duct stones for a 3-year period after endoscopic papillotomy (EPT).

METHODS

IDUS was carried out with a thin-caliber ultrasonic probe (diameter 2.0 mm, frequency 20 MHz) via transpapillary route after stone extraction. If IDUS showed evidence of residual stones and/or sludge, endoscopic management was performed until IDUS examination was negative. A prospective study was conducted on 59 consecutive patients undergoing additional IDUS after stone extraction between January 1996 and May 2003 (IDUS group). The recurrence rate of common bile duct stones was compared with a historical control group (August 1988 to December 1995) consisting of cases that did not undergo IDUS (non-IDUS group). Potential risk factors for recurrence of common bile duct stones were assessed by univariate and multivariate analysis on logistic regression.

RESULTS

In 14 of 59 patients (23.7%), IDUS detected small residual stones not seen on cholangiography. The recurrence rate was 13.2% (17 of 129 patients) in the non-IDUS group and 3.4% (two of 59 patients) in the IDUS group (P < 0.05). Multivariate analysis subsequently identified non-IDUS status as an independent risk factor for recurrence (odds ratio 5.12, 95% CI 1.11-23.52, P = 0.036).

CONCLUSIONS

Additional IDUS to confirm complete stone clearance after EPT decreases the early recurrence rate of common bile duct stones.

Nonoperative imaging techniques in suspected biliary tract obstruction

Evaluation of suspected biliary tract obstruction is a common clinical problem. Clinical data such as history, physical examination, and laboratory tests can accurately identify up to 90% of patients whose jaundice is caused by extrahepatic obstruction. However, complete assessment of extrahepatic obstruction often requires the use of various imaging modalities to confirm the presence, level, and cause of obstruction, and to aid in treatment plan. In the present summary, the literature on competing technologies including endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiopancreatography (PTC), endoscopic ultrasound (EUS), intraductal ultrasonography (IDUS), magnetic resonance cholangiopancreatography (MRCP), helical CT (hCT) and helical CT cholangiography (hCTC) with regards to diagnostic performance characteristics, technical success, safety, and cost-effectiveness is reviewed. Patients with obstructive jaundice secondary to choledocholithiasis or pancreaticobiliary malignancies are the primary focus of this review. Algorithms for the management of suspected obstructive jaundice are put forward based on current evidence. Published data suggest an increasing role for EUS and other noninvasive imaging techniques such as MRCP, and hCT following an initial transabdominal ultrasound in the assessment of patients with suspected biliary obstruction to select candidates for surgery or therapeutic ERCP. The management of patients with a suspected pancreaticobiliary condition ultimately is dependent on local expertise, availability, cost, and the multidisciplinary collaboration between radiologists, surgeons, and gastroenterologists.

Evaluation and management of periampullary tumors

Periampullary cancers make up 5% of all gastrointestinal cancers. The complexity of the periampullary anatomy makes determination of the origin of some of these tumors difficult. However, advances in imaging have helped with diagnosis as well as defining the extent of the lesion and its potential resectability. For many of these tumors, surgery is the recommended treatment. However, endoscopic removal is being extended to different lesions with encouraging preliminary results. Improvements in overall prognosis for periampullary tumors will be limited until diagnosis can be established earlier in the course of the disease and adjuvant therapies become more effective.

Innovative methods of biliary tract diagnosis: intraductal ultrasound and tissue acquisition

Tissue can be acquired from the bile and pancreatic duct with either brush cytology or biopsy forceps, often without the need for sphincterotomy. Although the diagnosis of malignancy with these sampling techniques is often specific, the sensitivity is limited, and a wide range of diagnostic accuracies has been reported. A combination of biopsy and brush cytology along with some newer techniques in the development stage may increase the sensitivity. Intraductal ultrasound is a newer technique offers the endoscopist the ability to image the bile and pancreatic duct wall, adjacent organs, and vascular structures with a high degree of detail. This visualization can be accomplished during the course of an ERCP or percutaneously under fluoroscopic guidance. Indications for the procedure include detection of choledocholithiasis, differentiation of benign and malignant ductal strictures, pancreaticobiliary tumor staging, and detection of various pancreatic tumors. Continued research into the design of the probes, which could improve durability and extend the depth of penetration, may promote more widespread use of this novel technology.

Clinical utility of intraductal US for evaluation of choledocholithiasis

BACKGROUND

Intraductal US can improve the diagnostic accuracy of cholangiography performed under C-arm fluoroscopy in patients with suspected choledocholithiasis. This study aimed to determine the clinical utility of intraductal US for patient management.

METHODS

Patients with suspected choledocholithiasis undergoing ERCP with a C-arm fluoroscope at two tertiary academic medical centers were enrolled. After initial cholangiography, findings and decisions concerning the need for further interventions were recorded. Intraductal US (20 MHz) was then selectively performed in patients with equivocal cholangiography or those without cholangiographic evidence of bile duct stones. Intraductal US was also performed after endoscopic sphincterotomy and stone extraction to confirm bile duct clearance.

RESULTS

Fifty-two patients (28 men, 24 women) were enrolled and intraductal US was selectively performed in 35 (64%). Of the 21 patients with normal cholangiography, 8 (38%) had stones or sludge by intraductal US. Endoscopic sphincterotomy was performed as a direct result of intraductal US in these 8 and the findings were confirmed in 7. In the 14 patients in whom cholangiography demonstrated small (<5 mm) or round filling defects, intraductal US concurred in 9 and found air bubble/no stone in 5. Sphincterotomy was avoided in these 5 patients. Overall, intraductal US led to a change in clinical management in 13 of 35 patients (37%) in whom it was performed.

CONCLUSIONS

Selective use of intraductal US affects the clinical management of a large proportion of patients who undergo C-arm fluoroscopy-guided ERCP for suspected bile duct stones.

Endoscopically inserted endoluminal receiver coil for high-resolution magnetic resonance imaging of the pancreas: Initial results in an animal model

BACKGROUND

This study assessed the feasibility of high-resolution magnetic resonance imaging of the pancreas by means of an endoscopically inserted endoluminal magnetic resonance receiver coil.

METHOD

A 0.032-inch diameter internal magnetic resonance imaging receiver coil was endoscopically inserted into the pancreatic duct in 4 pigs through the accessory channel of a standard duodenoscope to obtain high-resolution magnetic resonance images by using T1- and T2-weighted sequences.

RESULTS

The pig anatomy precluded the usual transoral approach; however, transgastric access allowed endoscopic transpapillary insertion of a receiver coil into the pancreatic duct in all animals without the need for sphincterotomy. The small swine pancreas could then be visualized by magnetic resonance imaging with a 0.3 x 0.3-mm in-plane resolution.

CONCLUSION

High-resolution pancreas magnetic resonance imaging is feasible by using an endoscopically inserted endoluminal receiver coil. The smaller stomach and larger pancreatic duct diameter in humans will facilitate clinical application of the imaging procedure.

Intraductal US is a useful adjunct to ERCP for distinguishing malignant from benign biliary strictures

BACKGROUND

Distinguishing malignant from benign biliary strictures remains a challenge. This prospective study assessed intraductal US as an adjunct to endoscopic retrograde cholangiography and tissue sampling for diagnosis of malignant and benign biliary strictures.

METHODS

Sixty-two patients were enrolled who had biliary strictures suspected to be malignant but with negative tissue sampling by endoscopic retrograde cholangiography, or suspected biliary strictures based on clinical manifestations and/or cross-sectional imaging. Intraductal US was performed with an over-the-wire 2.4-mm diameter 20 MHz catheter US probe. The diagnostic accuracy of endoscopic retrograde cholangiography plus tissue sampling with and without intraductal US was compared with surgical findings or clinical outcome at a 12-month follow-up (benign/malignant) in nonsurgical cases. Tissue sampling results were reported as malignant, suspicious for malignancy, atypical, or normal. Analysis was by intention-to-treat.

RESULTS

Two patients (3%) were excluded from analysis because the stricture could not be traversed with the intraductal US probe. Of the 60 remaining patients (37 men, mean age 64 years, range 27-89 years), 31 had malignant strictures (12 cholangiocarcinoma, 8 pancreatic, 5 metastatic, 3 gallbladder, 3 papilla), and 29 had benign strictures. Sphincterotomy was not required in any case to facilitate intraductal US. Fourteen patients (23%) underwent subsequent surgery including 11 with a preoperative diagnosis of resectable tumor. Endoscopic retrograde cholangiography/tissue sampling (atypia considered equivalent to benign) correctly identified 15 of 31 malignant strictures (p = 0.001) and all 29 benign strictures (p = 0.16) (accuracy 73%, sensitivity 48%, specificity 100%). The addition of intraductal US correctly identified 28 of 31 malignant strictures and 27 of 29 benign strictures (accuracy 92%, sensitivity 90%, specificity 93%). Of 11 patients with tumors who came to surgery, intraductal US correctly staged 4 (36%), understaged 5 (45%), missing metastatic lymph nodes in all cases and vascular invasion in 1 patient, and overstaged 2 (18%), with a false-positive diagnosis of metastatic lymph nodes in 1 and tumor mass in 1 patient who had no cancer at surgery.

CONCLUSION

Technically easy, intraductal US is a valuable adjunct to endoscopic retrograde cholangiography/tissue sampling that increases the ability to distinguish malignant from benign strictures. Intraductal US is unsuitable for assessing lymph nodes associated with malignant strictures.

Gastrointestinal endoscopic ultrasonography

Although conventional endoscopy provides excellent visualization of gastrointestinal mucosa, it provides little information about intramural or nearby extramural lesions. The imaging of intraabdominal structures by conventional transabdominal ultrasound is degraded by ultrasound energy attenuation with distance. The provision of an ultrasound probe on a flexible gastrointestinal endoscope, to form an echoendoscope, provides excellent imaging of the gastrointestinal wall and of adjacent extramural structures. During the last two decades, endoscopic ultrasound, using an echoendoscope, has revolutionized the diagnosis and treatment of gastrointestinal diseases that affect the submucosa, deep bowel wall, and adjacent extramural structures. This article reviews the role of endoscopic ultrasound in the diagnosis and treatment of gastrointestinal disease, including standard and promising new applications, as well as standard and emerging new technology.

Brush cytology of the biliary tract: retrospective study of 278 cases with histopathologic correlation

Bile aspiration during endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography has been used as a diagnostic tool in the evaluations of pancreatic and biliary tree strictures for the last two decades. However, recently biliary tract brush cytology has become the method of choice in evaluating pancreatic/biliary tract abnormalities. The aim of this study was to evaluate the accuracy of pancreatobiliary lesions by an endobiliary cytotechnique. From 1993-1999, 278 pancreatobiliary brushings were performed at our institutions. Cytologic material was air-dried for Diff-Quik stain or fixed in ethanol for Papanicolaou staining. The cytologic diagnoses were classified in three categories: 1) benign, 2) atypical/suspicious, or 3) malignant. Subsequent surgical biopsy was available in 87 (31%) patients. There were 150 males and 128 females with a mean age of 63 yr (range 22-97); 167 (60%) were benign cases. Follow-up surgical material was available in 39 cases, seven of which showed adenocarcinoma; 67 of all cases (24%) were atypical/suspicious cases. Follow-up surgical material was available in 31 cases, 17 (55%) of which showed adenocarcinoma; 32 cases (12%) were malignant cases. Follow-up surgical material was available in 15 cases. All 15 cases were in agreement with the cytologic diagnosis. Twelve (4%) cases were unsatisfactory for cytologic examination. Follow-up surgical material was available in two cases. One case showed mucinous cystadenoma of the pancreas. The other case showed benign duct epithelium. Our study shows a sensitivity of 68% and a specificity of 100%. Of the atypical cases, 55% were malignant on follow-up biopsy. Brush cytology of pancreatobiliary strictures is the most widely used technique in the diagnosis of carcinoma, with a high degree of specificity.

Over-the-wire US catheter probe as an adjunct to ERCP in the detection of choledocholithiasis

BACKGROUND

Intraductal ultrasound (IDUS) as an adjunct to ERCP for detection of extrahepatic bile duct stones is technically easy, accurate, and safe. This prospective study evaluated IDUS with an "over-the-wire" catheter US probe as an adjunct to ERCP.

METHODS

Sixty-five patients, highly suspected to have choledocholithiasis, underwent IDUS during ERCP. The IDUS probe was inserted by means of the duodenoscope into the bile duct without performing a sphincterotomy. All stones identified by IDUS or retrograde cholangiography were removed with either a basket or retrieval balloon after endoscopic sphincterotomy.

RESULTS

The final diagnosis was choledocholithiasis in 59 patients. Bile duct diameter ranged from 0.6 to 2.3 cm and stone size from 2 mm to 2 cm. IDUS successfully identified all stones in these patients. IDUS resulted in 2 false-positive diagnoses in the remaining 6 patients without stones (overall accuracy 97%, sensitivity 100%, specificity 67%). Cholangiography detected stones in 55 of the patients with stones (accuracy 94%, sensitivity 93%, specificity 100%).

CONCLUSION

IDUS, a safe, technically easy procedure, is highly accurate in the detection of extrahepatic bile duct stones regardless of the diameter of the bile ducts. The "over-the-wire" technique preserves access to the cannulated duct. IDUS is an excellent adjunct to ERCP for the diagnosis of choledocholithiasis. IDUS differentiates stones from air bubbles and prevents unnecessary sphincterotomy.

The combination of stricture dilation, endoscopic needle aspiration, and biliary brushings significantly improves diagnostic yield from malignant bile duct strictures

BACKGROUND

Brush cytology, routinely performed at ERCP to assess malignant-appearing biliary strictures, is limited by relatively low sensitivity and negative predictive value. This study assessed whether the combination of stricture dilation, endoscopic needle aspiration, and biliary brushing improves diagnostic yield.

METHODS

In a prospective nonrandomized study, 46 consecutive patients were evaluated with malignant-appearing biliary strictures at ERCP. Twenty-four patients (Group A) underwent standard brush cytology alone and 22 patients (Group B) underwent stricture dilatation to 10F, endoscopic needle aspiration, and subsequent biliary brushing by using the Howell biliary system. The diagnostic yields for both techniques were compared.

RESULTS

Of the 46 patients, 34 had proven malignant strictures (14 Group A, 20 Group B). Compared with brushing alone, the combination of stricture dilatation, endoscopic needle aspiration, and subsequent biliary brushing significantly increased both the sensitivity (57% vs. 85%, p < 0.02) and specificity (80% vs. 100%, p < 0.02) of cytology with positive brushings in all patients with pancreatic or gallbladder carcinoma.

CONCLUSIONS

The combination of stricture dilation, endoscopic needle aspiration, and biliary brushing significantly improves diagnostic yield for malignant bile duct strictures and may particularly be of benefit for extrinsic strictures caused by pancreatic or gallbladder carcinoma.

Intraductal ultrasonography for hepatocellular carcinoma with tumor thrombi in the bile duct: comparison with polypoid cholangiocarcinoma

BACKGROUND AND AIM

Tumor thrombi in the bile duct caused by hepatocellular carcinoma (HCC), and cholangiocarcinoma show polypoid lesions on cholangiographic findings. This study prospectively compared the images of intraductal ultrasonography between HCC and polypoid cholangiocarcinoma.

METHODS

In five patients with tumor thrombi in the bile duct caused by HCC, a 2.0 mm diameter ultrasonic probe with a frequency of 20 MHz was inserted into the bile duct via the transpapillary route (n = 4) or the transhepatic route (n = 1). The images were compared to that of 65 patients with cholangiocarcinoma.

RESULTS

In all patients with HCC, intraductal ultrasonography showed a 'polypoid tumor with a narrow base'. In 16 of 65 patients with cholangiocarcinoma, it showed a 'polypoid tumor with a narrow base'. When intraductal ultrasonography showed a 'polypoid tumor with a narrow base', the findings of a positive 'nodule within a nodule' (40 vs 0%; P < 0.05), and the absence of a 'papillary-surface pattern' (80 vs 13%; P < 0.05) were more highly associated with tumor thrombi caused by HCC than to polypoid-type cholangiocarcinoma.

CONCLUSIONS

Intraductal ultrasonography was useful to distinguish between tumor thrombi caused by HCC and polypoid-type cholangiocarcinoma.

Wire-guided intraductal US: an adjunct to ERCP in the management of bile duct stones

BACKGROUND

Endoscopic retrograde cholangiography (ERC) may misdiagnose bile duct stones if air bubbles are introduced during contrast injection, and it may also fail to diagnose stones in the presence of bile duct dilation.

METHODS

Our aim was to determine whether intraductal US (IDUS) improves the accuracy of cholangiography and whether it is a useful adjunct in the management of bile duct stones. IDUS with a wire-guided US probe was performed after initial ERC in patients in whom bile duct stones were suspected. The diagnostic accuracy of ERC alone was compared with that of ERC plus IDUS.

RESULTS

ERC with IDUS was performed in 62 patients who were suspected to have bile duct stones. Both IDUS and ERC were performed by the same endoscopist, and ERC was performed with a C-arm fluoroscope. The presence of bile duct stones and/or sludge were confirmed after sphincterotomy and extraction in 34 patients. Overall, the accuracy of ERC combined with IDUS in the diagnosis of bile duct stone and/or sludge was higher than that of ERC alone (97% vs. 87%, p < 0.05). With dilated bile ducts, the diagnostic accuracy of ERC combined with IDUS was also higher than that of ERC alone (95.5% vs. 72.7%, p < 0.05). Additional diagnostic information provided by IDUS included identification of cystic duct stones in 5 patients, characterization of bile duct strictures in 2 patients, and choledochal varices in 1 patient. Performance of wire-guided IDUS required 5% of the total procedure time.

CONCLUSIONS

IDUS improves diagnostic accuracy of ERC and is a useful adjunct to ERC when bile duct stones are suspected.

Pancreas: imaging diagnosis with color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography

Recent advances of ultrasound imaging have made possible to depict various diseases and conditions of the pancreas. Color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography are feasible to show vascular abnormalities, differentiate the solid and cystic tumors, decide tumor extent, and help to perform interventional treatments of the pancreatic diseases. Those techniques will contribute to the more precise and easier diagnosis and to prompt decision of the treatments of the pancreatic disorders. Radiologists should recognize the diagnostic feasibility and limitations of those techniques in order to avoid unnecessary examinations on the patients, and obtain precise diagnostic images.

Multiple bile duct biopsies using a sheath with a side port: usefulness of intraductal sonography

OBJECTIVE

We clarified the number of biopsies required to determine malignancy of the biliary tract on the basis of the type of bile duct tumor.

SUBJECTS AND METHODS

Patients with a biliary tract malignancy (n = 33) and a benign biliary stenosis (n = 3) underwent biopsy via the percutaneous transhepatic route. We performed intraductal sonography using a 20-MHz probe with a 2.0-mm diameter. The sonographic findings were prospectively classified as polypoid, circular, or semicircular. The tip of a long 9-French sheath with a side port was wedged into the stenosis, and six specimens were obtained with a 1.8-mm-diameter forceps with serrated cups.

RESULTS

When cholangiography or intraductal sonography showed a polypoid lesion, the sensitivity of two biopsies was 100% (6/6). When cholangiography showed a stenotic lesion, the sensitivity of nine biopsies (96%, 26/27) was superior to that of two biopsies (74%, 20/27; p < 0.05). When intraductal sonography showed a circular lesion, the sensitivity of three biopsies (100%, 14/14) was superior to that of a single biopsy (64%, 9/14; p < 0.05). When it showed a semicircular lesion, the sensitivity of nine biopsies (92%, 12/13) was superior to that of two biopsies (54%, 7/13; p < 0.05).

CONCLUSION

Bile duct biopsy using a sheath with a side port has a high sensitivity. However, the number of biopsies required depends on the cholangioscopic and intraductal sonographic appearance of the tumor.

Transpapillary intraductal US prior to biliary drainage in the assessment of longitudinal spread of extrahepatic bile duct carcinoma

BACKGROUND

The utility of intraductal US via the transpapillary route prior to biliary drainage in the assessment of longitudinal extension of extrahepatic bile duct carcinoma was investigated.

METHODS

In 19 patients with extrahepatic bile duct carcinoma who underwent surgical resection, an ultrasonic probe (diameter, 2.0 mm; frequency, 20 MHz) was inserted into the bile duct via the transpapillary route prior to biliary drainage. Longitudinal cancer extension along the bile duct was prospectively determined and compared with the histologic findings in the resected specimens.

RESULTS

Results on the hepatic side were as follows: Intraductal US demonstrated more extensive longitudinal cancer spread than cholangiography in 9 of 19 patients with one instance of overdiagnosis. The accuracy of intraductal US in assessing the extent of spread (84%) was superior to that of cholangiography (47%) (p < 0.05). Results on the duodenal side were as follows: In patients with suprapancreatic bile duct cancer (n = 14), intraductal US demonstrated more extensive longitudinal cancer spread than cholangiography in 8 of 14 patients. The accuracy of intraductal US in assessing the extent of the spread (86%) was superior to that of cholangiography (43%) (p < 0.05).

CONCLUSIONS

Transpapillary intraductal US prior to biliary drainage is useful in demonstrating longitudinal extension of bile duct cancer. However, the surgical margins were inaccurate in some patients.

Ropeway-type bile duct biopsy forceps with a side slit for a guidewire

BACKGROUND

Transpapillary procurement of bile duct biopsy specimens is an effective diagnostic technique in cases of biliary structure. The utility of new ropeway-type bile duct biopsy forceps with a side slit for a guidewire was investigated in this study.

METHODS

The 12 patients in this study had bile duct cancer (n = 3), cancer of the head of the pancreas (n = 4), gallbladder cancer (n = 1), and benign bile duct stenosis (n = 4). After endoscopic retrograde cholangiography, a guidewire was placed in the bile duct across the stenosis. The new forceps (1.8-mm diameter clamshell-type biopsy forceps without needle) was then introduced through the intact papilla along the guidewire.

RESULTS

In all patients, sufficient tissue for histopathologic evaluation was obtained without complication. In one patient, biopsy specimens were selectively obtained of the left hepatic duct, which was impossible with conventional forceps. In another patient, histologic examination of specimens obtained by using this new forceps showed adenocarcinoma, whereas specimens obtained with a conventional forceps did not contain adenocarcinoma. However, in another patient, biopsy specimens obtained with a conventional forceps contained adenocarcinoma that was not evident in specimens obtained with the new forceps. Dislodgement of the guidewire during procurement of biopsy specimens occurred in 1 patient. In the other 11 patients, an endoscopic biliary drain was inserted over the guidewire.

CONCLUSION

The new ropeway-type biopsy forceps is useful for selectively obtaining biopsy specimens of the bile duct. With this system, access for subsequent endoscopic biliary drainage is maintained.