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Maurits J Wiersema

Publications and source records attributed to Maurits J Wiersema.

At least 19 recordsLinked to original sources

Evaluation of a new curved linear array echoendoscopy system for EUS.

BACKGROUND: EUS-FNA can be used to accurately diagnose and stage GI and pulmonary neoplasms. This study evaluated the performance characteristics of a new compact linear EUS system during EUS-FNA. METHODS: A total of 37 patients enrolled in this prospective pilot study underwent clinically indicated EUS-FNA and/or celiac plexus neurolysis with the compact EUS system. RESULTS: The mean time to perform a radial and linear array EUS with FNA and/or celiac plexus neurolysis was 24 minutes shorter with the compact EUS system compared with that for an historical control procedure in which a conventional linear EUS unit was used (p = 0.0007). The EUS images and visualization of the needle during EUS-FNA were rated good to excellent in greater than 95% of the patients. With respect to ease of esophageal intubation, duodenal intubation, and general maneuverability, the performance of the new linear echoendoscope, compared with a radial scanning videoechoendoscope, was the same or better in, respectively, 85%, 87%, and 100% of procedures. The video image quality of the new linear array echoendoscope was superior to that of the radial scanning videoechoendoscope in all patients. No complications were encountered. CONCLUSIONS: EUS-FNA and celiac plexus neurolysis can be performed safely with the new compact EUS system. The efficiency of this procedure is enhanced compared with historical experience with other instruments. Although image quality is sufficient for EUS-FNA and celiac plexus neurolysis, the compact unit cannot be used as a "stand-alone" system for routine diagnostic EUS, and its use must be complemented by standard radial imaging.

Biopsy, Needle↗

A simple phantom for learning EUS-guided FNA.

BACKGROUND: The learning curve for EUS-guided FNA (EUS-FNA) is formidable. Development of a phantom to assist in teaching the technique may be beneficial. This study assessed the feasibility of using a low-cost phantom made of commonly available materials to practice EUS-FNA. METHODS: A 2500-mL barium enema bag was modified by running a plastic tube (3-mm inner diameter) through it and sealing one end. One hundred grams of standard agar were suspended in 4 liters of tap water. The broth was heated slowly to boiling. The dissolved agar was then transferred to the barium enema bag after mixing in diced carrots, elbow macaroni, peas, and fingertips of surgical gloves filled with 5 mL of normal saline solution (6 of each) to simulate solid and cystic lesions. Immersion of the phantom in a basin of water provided acoustic coupling. One end of the 3-mm plastic tubing was attached to the nozzle of a water jet device and the other end to its reservoir to create a closed system allowing water recirculation. A linear array echoendoscope and a fine needle were used to perform EUS-FNA. The analysis is descriptive. OBSERVATIONS: The phantom was readily made with inexpensive components (total cost <$50). With refrigeration the phantom was used repetitively during a 4-month period. It produced EUS images with an echotexture comparable with liver. The solid and cystic components resembled hepatic cysts and solid masses encountered when performing EUS in humans. Under EUS-guidance, fine-needle aspirates of selected lesions could be performed allowing targeting, aspiration, and sampling of selected lesions. The Doppler flow effect allowed examination of a simulated vascular structure during FNA. CONCLUSIONS: Once validated, an EUS phantom made of simple components may become an invaluable educational tool for teaching EUS-FNA. Further studies are needed to determine how it affects the skills of gastroenterologists with and without EUS experience.

Biopsy, Needle↗

Prospective risk assessment of bacteremia and other infectious complications in patients undergoing EUS-guided FNA.

BACKGROUND: There are few data regarding the risk of bacteremia with EUS-guided FNA. This study prospectively evaluated the frequency of bacteremia and other infectious complications after EUS-guided FNA. METHODS: Patients referred for EUS-guided FNA of the upper GI tract lesions were considered for enrollment. Patients were excluded if there was an indication for preprocedure administration of antibiotics based on ASGE guidelines, had taken antibiotics within the prior 7 days, or if they had a pancreatic cystic lesion. Blood cultures were obtained immediately before the procedure, after routine endoscopy/radial EUS, and 15 minutes after EUS-guided FNA. RESULTS: Fifty-two patients underwent EUS-guided FNA at 74 sites (mean 1.4 sites/patient) totaling 266 passes of the fine needle (mean 5.1 FNA/patient). Coagulase negative Staphylococcus was grown in cultures from 3 patients (5.8%; 95% CI [1%, 15%]) and was considered a contaminant. Three patients (5.8%; 95% CI [1%, 15%]) developed bacteremia: Streptococcus viridans (n = 2), unidentified gram-negative bacillus (n = 1). No signs or symptoms of infection developed in any patient. CONCLUSION: EUS-guided FNA of solid lesions in the upper GI tract should be considered a low-risk procedure for infectious complications that does not warrant prophylactic administration of antibiotics for prevention of bacterial endocarditis.

Adult↗

Development of a swine model for benign stenosis of the bile duct by endoscopic application of intraluminal thermal injury.

BACKGROUND: A simple animal model is desirable for the study of endoscopic therapies used in the management of biliary strictures. The aim of this study was to identify a method for inducing benign biliary stenoses in a porcine model by using endoscopic techniques. METHODS: Endoscopic retrograde cholangiography was performed in 9 swine. Intraluminal injury was applied to the common hepatic duct with graded applications of either a heat probe or a multipolar probe. Cholangiography was repeated at 7-day intervals. If a stricture was not identified by 28 days, injury was created at another site in the common hepatic duct by using a higher energy dose. After a stricture was identified, the animal was killed and bile duct samples were obtained for histopathologic evaluation. RESULTS: Thirteen thermal injuries were created in the 9 animals. Six of 7 heat probe treatments and 1 of 6 multipolar probe treatments resulted in a stricture (p = 0.025, Fisher exact test). Applications of the heat probe at 10 or 15 J produced a stricture in 6 of 6 cases. All strictures were indistinguishable histopathologically from benign strictures in humans. CONCLUSIONS: The application of intraluminal thermal injury with a heat probe results in a reproducible animal model of benign biliary stenosis.

Animals↗

Preliminary experience with an EUS-guided trucut biopsy needle compared with EUS-guided FNA.

BACKGROUND: EUS-guided FNA is a sensitive method for the diagnosis of malignancy. However, EUS-FNA is often laborious and usually requires the presence of a cytopathologist or cytotechnician. The development of an EUS-guided Trucut biopsy (EUS-TCB) needle may simplify the procedure and expand the application of EUS-directed procurement of biopsy specimens. The aim of this study was to determine the feasibility of using the EUS-TCB for the diagnosis of intraintestinal and extraintestinal lesions and compare the results with this needle with those of EUS-FNA. METHODS: The EUS-TCB and EUS-FNA were used to evaluate patients with known or suspected intraintestinal or extraintestinal mass lesions and/or lymphadenopathy. Patient records were retrospectively reviewed to determine the accuracy and safety of both techniques. RESULTS: Nineteen patients had tissue samples obtained with both the EUS-TCB and EUS-FNA from 20 sites (2 sites in 1 patient) between December 2001 and March 2002. Accuracy was higher with EUS-TCB than EUS-FNA, although the difference was not significant (85% vs. 60%), despite performing fewer passes with the former (mean [SD] 2.0 [0.7], range 1-4; vs. mean 3.3 [1.5], range 1-10; p < 0.05). No complications were identified. CONCLUSIONS: This preliminary study suggests EUS-TCB can safely be used to obtain biopsy specimens of intraintestinal and extraintestinal mass lesions and lymphadenopathy. Its use may reduce the number of needle passes compared with EUS-FNA. This may reduce costs by shortening the procedure, diminishing the need for an onsite cytopathologist or technician, and lowering the frequency of nondiagnostic procedures. Prospective studies are needed to verify these findings.

Aged↗

Utility of Web-based assessment of patient satisfaction with endoscopy.

OBJECTIVES: The dramatic growth of the World Wide Web (Web) holds potential for use in survey distribution and submission. Its use has not previously been studied in the context of patient satisfaction with endoscopy procedures. In this study we compared standard mail, telephone, and Web-based modes of endoscopy satisfaction survey administration with respect to response rate and response content. METHODS: An endoscopy satisfaction questionnaire consisting of seven core items from the modified Group Health Association of America (GHAA-9) was distributed to patients after routine outpatient endoscopy. Patients were randomized to receive the questionnaire by standard mail, telephone, or Web (if applicable). Response rates and satisfaction scores in the groups were compared. The nonresponders to the standard mail and Web surveys were subsequently contacted by telephone to determine their level of satisfaction. RESULTS: Response rates to the telephone survey (81% among those designated as non-Web users and 78% among Web users) and standard mail (75% non-Web users, 67% Web users) were higher than response rate to the Web-based survey (34%) (p < or = 0.0005). There was no significant difference in satisfaction scores among the groups or between satisfaction of nonresponders and responders. CONCLUSIONS: The potential of our Web-based survey was limited by poor response rates. This arose from privacy protection precautions that complicated access to the Web site. Future Web-based strategies for surveying patients will need to be more user-friendly while maintaining the intent of the recent Health Insurance Portability and Accountability Act regulations.

Adult↗

The role of endoscopic ultrasound in hepatobiliary disease.

The evaluation of hepatobiliary disease continues to change as new technologies are introduced. One of the more recent advances in hepatobiliary imaging has been the application of endoscopic ultrasound (EUS). Endoscopic retrograde cholangiopancreatography, computed tomography, conventional ultrasound, and magnetic resonance imaging were previously the primary means of evaluating hepatobiliary disease. The role of EUS as both a substitute and a complement for these historical imaging modalities continues to evolve. This review examines the current literature on EUS in the evaluation of hepatobiliary diseases, including choledocholithiasis, microlithiasis, biliary strictures, obstructive jaundice, cholangiocarcinoma, gallbladder polyps, and liver lesions.

Biliary Tract Diseases↗

Use of a phased vector array US catheter for EUS.

BACKGROUND: Existing EUS catheter probes have limited depth of penetration and lack color flow and Doppler capabilities. This study prospectively assessed the feasibility and safety of using a phased vector array US catheter in the human GI tract. METHODS: Eleven patients underwent EUS with a steerable 9F phased vector array catheter. Images obtained with the catheter were compared with standard EUS images. RESULTS: The GI wall layers were equally well imaged with the catheter compared with standard echoendoscopes in 90% of the cases. Images of the liver, spleen, pancreatic parenchyma, and pancreatic duct were of equal quality and resolution with both techniques in the majority of patients. Some deeper structures and blood vessels were better visualized with the catheter. No complications were encountered. CONCLUSION: The steerable phased vector array US catheter is a safe device when used in the GI tract and offers images comparable with those obtained with a dedicated echoendoscope. Further studies are needed to determine the accuracy of tumor staging and clinical utility of this device.

Adult↗

Safety and outcome of endoscopic snare excision of the major duodenal papilla.

BACKGROUND: The optimal management of adenoma of the major duodenal papilla is not established. Options include surgical excision, endoscopic ablative techniques, snare excision, and observation with periodic biopsies. The aims of this retrospective study were to determine the safety and outcome of snare excision of the papilla. METHODS: Twenty-eight snare excisions of the papilla were performed in 26 patients. Sixteen had familial adenomatous polyposis. In 22 procedures, a minisnare was used, and in 6 cases a prototype snare was designed for excision of the papilla. Pancreatic stents were placed as a prophylactic measure at the discretion of the endoscopist (n = 10). RESULTS: Histopathologically, resected tissue included 25 adenomas, 1 inflammatory polyp, 1 invasive malignancy, and 1 normal papilla. Immediate complications were minor bleeding (n = 2), mild pancreatitis (n = 4) and a duodenal perforation (n = 1). The presence (n = 10) or absence (n = 18) of a pancreatic stent did not correlate with subsequent pancreatitis (2 in each group, p = NS). Follow-up was available for 21 patients (median, 9 months; range, 2-32 months). Pancreatic duct stenosis at the papillectomy site resulted in pancreatitis in 2 patients (17%) at, respectively, 4 months and 24 months. Follow-up endoscopy revealed recurrent/residual adenomatous tissue in 2 (10%). CONCLUSIONS: Snare excision of the major duodenal papilla was well tolerated. Most complications were mild except for a small duodenal perforation. Stenosis of the pancreatic duct orifice with pancreatitis may be a late complication.

Adenomatous Polyposis Coli↗

Initial experience with EUS-guided trucut needle biopsies of perigastric organs.

BACKGROUND: The aims of this study were to determine the feasibility, safety, and yield of a 19-gauge EUS-guided-trucut needle for obtaining biopsy specimens of perigastric organs. METHODS: The study was performed in swine under general anesthesia. EUS-guided trucut needle biopsy specimens were obtained from the spleen, liver, pancreas body, and left kidney. Biopsy specimens were assessed for size, fragmentation, and representation of the target organ. OBSERVATIONS: Twenty-eight biopsy specimens were obtained from the 4 target organs with two needles. Median biopsy length was 6 mm (spleen), 4 mm (liver), 6 mm (left kidney), and 2 mm (pancreas body). Of all the specimens, 75% to 100% had tissue representative of the target organ. EUS visualization of the needle was excellent and no complications were identified. CONCLUSIONS: Use of the trucut needle under EUS guidance to obtain biopsy specimens of perigastric organs appears safe and yields specimens that are representative of the target organ sampled. Further study of the utility and safety of this needle in humans is warranted.

Animals↗

Usefulness of EUS-guided fine needle aspiration (EUS-FNA) in the diagnosis of functioning neuroendocrine tumors.

BACKGROUND: Localization of neuroendocrine tumors may be challenging. The role of EUS-FNA in this setting is unknown. METHODS: Ten patients with clinically suspected functioning neuroendocrine tumors (hormonal disturbances) underwent EUS-FNA to determine the location and to confirm the diagnosis cytologically. OBSERVATIONS: EUS identified 14 tumors in these 10 patients. In all but one patient CT did not demonstrate the tumor or missed at least one of multiple lesions. Mean tumor size was 12 mm (range 4-25 mm). Tumor locations were pancreas (n = 13) and duodenal wall (n = 1). Eleven of the 14 detected lesions were aspirated under EUS with accurate diagnosis in all cases. Surgical confirmation of EUS-FNA findings was available in 7 patients. There was no complication of EUS-FNA. CONCLUSIONS: EUS is a highly accurate technique for visualization of small functioning neuroendocrine tumors not evident on CT and for identification of patients with multiple lesions. EUS-FNA safely provides cytologic confirmation with high accuracy in these patients.

Adult↗

Endoscopic ultrasound for rectal cancer.

The application of EUS has improved the way we evaluate and manage patients with rectal cancer. EUS has substantially greater sensitivity than CT in detecting advanced T stage tumors. Such improved sensitivity results in changes in preoperative therapy that would not otherwise have occurred without EUS. Although the addition of FNA provides little incremental effect on patient management, it carries the most potential for impacting management in those patients with early T stage disease, and its use should be considered in this subgroup of patients. Whether the accurate staging ability of EUS translates into improved outcomes in terms of reduced recurrence rates and ultimately prolonged survival remains uncertain. This will require further long-term outcome studies focusing on the endpoint of tumor recurrence and patient survival.

Endosonography↗

Endoscopic ultrasound techniques for pancreatic cystic neoplasms.

The role of EUS and EUS FNA in the evaluation of cystic pancreatic lesions is evolving. The detailed imaging provided by EUS and hence the ability to target the biopsy at suspicious areas within the pancreatic cystic lesion may prove to be invaluable. Improvements in EUS equipment will further secure the role of this technology when evaluating these patients.

Biopsy, Needle↗

A prospective, blinded assessment of the impact of preoperative staging on the management of rectal cancer.

BACKGROUND & AIMS: The influence of preoperative staging of rectal carcinoma on therapeutic decisions is uncertain. The use of fine-needle aspiration (FNA) of perirectal nodes in this setting has not been evaluated. The aim of this prospective, blinded study of patients with rectal cancer was to assess the impact of preoperative staging on treatment decisions and compare the tumor (T), nodal (N) staging performance characteristics of pelvic computed tomography (CT), rectal endoscopic ultrasonography (EUS), and EUS FNA. METHODS: Eighty consecutive patients with newly diagnosed rectal cancer were prospectively evaluated. Therapy decisions were recorded after sequential disclosure of staging information to the patient's surgeon. RESULTS: In 31% of patients (95% confidence interval, 21%-42%), EUS staging information changed the surgeon's original treatment plan based on CT alone. The further addition of FNA changed therapy in one patient. T staging accuracy was 71% (CT) and 91% (EUS) (P = 0.02); N staging accuracy was 76% (CT), 82% (EUS), and 76% (EUS FNA) (P = NS). CONCLUSIONS: Preoperative staging with EUS results in more frequent use of preoperative neoadjuvant therapy than if staging was performed with CT alone. The addition of FNA only changed the management of one patient, whereas FNA did not significantly improve N staging accuracy over EUS alone. FNA seems to offer the most potential for impacting management in those patients with early T stage disease, and its use should be confined to this subgroup of patients. EUS is more accurate than CT for determining T stage of rectal carcinoma.

Aged↗

Study of recurrence after surgical resection of intraductal papillary mucinous neoplasm of the pancreas.

BACKGROUND & AIMS: The aim of this study was to determine recurrence and long-term survival after resection of pancreatic intraductal papillary mucinous neoplasm and to correlate recurrence and survival with histology, extent of resection, and duration of follow-up. METHODS: A single pathologist, without knowledge of previous interpretations of histology or clinical data, retrospectively reviewed and classified 113 resected intraductal papillary mucinous neoplasms as invasive carcinoma (n = 40) or as noninvasive neoplasms (adenoma, borderline, or carcinoma in situ; n = 73). Data on recurrence (locoregional or metastatic), follow-up, and cause of death were obtained from patient records and/or by contacting patients and their physicians. RESULTS: In invasive intraductal papillary mucinous neoplasm, recurrence was similar after partial pancreatectomy (18/27; 67%) and total pancreatectomy (8/13; 62%) and occurred within 3 years of resection in 91%. Among noninvasive neoplasms, 5 of 60 (8%) recurred after partial pancreatectomy (median follow-up, 37 months); none recurred after total pancreatectomy (n = 13; median follow-up, 32 months). Recurrence after resection in noninvasive neoplasms was diagnosed after a median of 40 months (range, 23-75 months); recurrence was noninvasive in 3 and invasive cancer in 2. Five-year survival was better for noninvasive compared with invasive intraductal papillary mucinous neoplasm (84.5% vs. 36%; P < 0.001). CONCLUSIONS: Invasive intraductal papillary mucinous neoplasm recurs frequently even after a complete "curative" resection and portends poor survival. In contrast, noninvasive intraductal papillary mucinous neoplasm recurs infrequently after resection, and survival is excellent regardless of the degree of epithelial dysplasia in the tumor.

Adenocarcinoma, Mucinous↗

High-frequency US catheter-based staging of early esophageal tumors.

BACKGROUND: High-frequency catheter US probes provide greater accuracy compared with dedicated echoendoscopes in the staging of superficial esophageal carcinoma. However, it may be difficult and time consuming to obtain acoustic coupling with these devices. The aim of this study was to test a novel catheter US technique for staging superficial esophageal carcinoma. METHODS: Twelve patients underwent examination with a 2-channel endoscope. US images were obtained with a catheter US probe (20 MHz) fitted with a balloon sheath. RESULTS: Adequate endoscopic and catheter US images were obtained in all patients. Depth of tumor invasion as determined with the catheter US probe was confirmed in all 5 patients who underwent surgery. No procedure-related complications occurred. CONCLUSIONS: US with a catheter US probe and sheath allows complete endoscopic examination and preoperative determination of depth of invasion of superficial esophageal carcinoma in a single endoscopic procedure. Preliminary results suggest this technique is accurate and safe.

Adenocarcinoma↗