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M J Wiersema

Publications and source records attributed to M J Wiersema.

At least 19 recordsLinked to original sources
PubMed2001

The reliability of EUS for the diagnosis of chronic pancreatitis: interobserver agreement among experienced endosonographers.

BACKGROUND: Endoscopic ultrasound (EUS) is a minimally invasive, low risk method of diagnosis for chronic pancreatitis (CP). The degree to which endosonographers agree on the features and diagnosis of CP is unknown. For EUS to be considered an accurate test for CP, there must be good interobserver agreement. METHODS: Forty-five pancreatic EUS examinations were videotaped by 3 experienced endosonographers. Examinations from 33 patients with suspected CP based on typical symptoms, as well as 12 control patients without suspected CP, were included. Eleven experienced endosonographers ("experts") who were blinded to clinical information independently evaluated all videotaped examinations for the presence of CP and the following 9 validated features of CP: echogenic foci, strands, lobularity, cysts, stones, duct dilatation, duct irregularity, hyperechoic duct margins, and visible side branches. The experts also ranked (most to least) which features they believed to be the most indicative of CP. Interobserver agreement was expressed as the kappa (kappa) statistic. RESULTS: There was moderately good overall agreement for the final diagnosis of CP (kappa = 0.45). Agreement was good for individual features of duct dilatation (kappa = 0.6) and lobularity (kappa = 0.51) but poor for the other 7 features (kappa < 0.4). The expert panel had consensus or near consensus agreement (greater than 90%) on 206 of 450 (46%) individual EUS features including 22 of 45 diagnoses of CP. Agreement on the final diagnosis of CP was moderately good for those trained in third tier fellowships (kappa = 0.42 +/- 0.03) and those with more than 1100 lifetime pancreatic EUS examinations (kappa = 0.46 +/- 0.05). The presence of stones was regarded as the most predictive feature of CP by all endosonographers, followed by visible side branches, cysts, lobularity, irregular main pancreatic duct, hyperechoic foci, hyperechoic strands, main pancreatic duct dilatation, and main duct hyperechoic margins. The most common diagnostic criterion for the diagnosis of CP was the total number of features (median 4 or greater, range 3 or greater to 5 or greater). CONCLUSIONS: EUS is a reliable method for the diagnosis of chronic pancreatitis with good interobserver agreement among experienced endosonographers. Agreement on the EUS diagnosis of chronic pancreatitis is comparable to other commonly used endoscopic procedures such as bleeding ulcer stigmata and computed tomography of the brain for stroke localization and better than the physical diagnosis of heart sounds.

Chronic Disease↗
PubMed2001

Utility of endoscopic ultrasonography in endoscopic drainage of pancreatic pseudocysts in selected patients.

OBJECTIVES: To determine the effect of endoscopic ultrasonography (EUS) on endoscopic drainage of pancreatic pseudocysts and to determine patency with fistula dilation and placement of multiple stents. PATIENTS AND METHODS: Between September 1995 and January 1999, 19 patients underwent endoscopic drainage of pancreatic pseudocysts, 17 of whom were assessed by EUS before drainage. Radial EUS scanning was used to detect an optimal site of apposition of pseudocyst and gut wall, free of intervening vessels. A fistula was created with a fistulatome, followed by balloon dilation of the fistula tract. Patency was maintained with multiple double pigtail stents. The primary goal of this retrospective study was to determine whether EUS affected the practice of endoscopic drainage of pancreatic pseudocysts. RESULTS: In 3 patients, drainage was not attempted based on EUS findings. In the other 13 patients (14 pseudocysts), creation of a fistula was successful on 13 occasions, and no immediate complications occurred. However, 1 patient subsequently developed sepsis that required surgery. All other patients were treated with balloon dilation, multiple stents, and antibiotics, with no septic complications. Of 14 pseudocysts (in 13 patients), 13 (93%) resolved. CONCLUSIONS: Results of EUS may alter management of patients considered for endoscopic drainage of pancreatic pseudocysts. Endoscopic ultrasonography was useful for selecting an optimal and safe drainage site. The combination of balloon dilation, multiple stents, and antibiotics appears to resolve pancreatic pseudocysts without septic complications.

Adult↗
PubMed2001

A comparison of endoscopic ultrasound, magnetic resonance imaging, and exam under anesthesia for evaluation of Crohn's perianal fistulas.

BACKGROUND & AIMS: To determine accuracy of endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) for evaluation of Crohn's disease perianal fistulas. METHODS: Thirty-four patients with suspected Crohn's disease perianal fistulas were prospectively enrolled in a blinded study comparing EUS, MRI, and examination under anesthesia (EUA). Fistulas were classified according to Parks' criteria, and a consensus gold standard was determined for each patient. Acceptable accuracy was defined as agreement with the consensus gold standard for > or =85% of patients. RESULTS: Three patients did not undergo MRI; 1 did not undergo EUS or EUA; and consensus could not be reached for 1. Thirty-two patients had 39 fistulas (20 trans-sphincteric, 5 extra-sphincteric, 6 recto-vaginal, 8 others) and 13 abscesses. The accuracy of all 3 modalities was > or =85%: EUS 29 of 32 (91%, confidence interval [CI] 75%-98%), MRI 26 of 30 (87%, CI 69%-96%), and EUA 29 of 32 (91%, CI 75%-98%). Accuracy was 100% when any 2 tests were combined. CONCLUSIONS: EUS, MRI, and EUA are accurate tests for determining fistula anatomy in patients with perianal Crohn's disease. The optimal approach may be combining any 2 of the 3 methods.

Adolescent↗
PubMed2001

Acute extraluminal hemorrhage associated with EUS-guided fine needle aspiration: frequency and clinical significance.

BACKGROUND: Complications with EUS-guided fine needle aspiration cytology (EUS-guided FNA) are rare and include perforation, infection, pancreatitis, and intraluminal bleeding. To date, the ultrasound appearance and clinical significance of perilesional bleeding during EUS-guided FNA have not been described. The aim of this study was to analyze the frequency of acute extraluminal hemorrhage associated with EUS-guided FNA. METHODS: From September 1998 to October 1999 EUS-guided FNA was performed during 227 of 1104 EUS procedures. Patient follow-up and complications were recorded and retrospectively analyzed. OBSERVATIONS: Three patients were identified with acute extraluminal hemorrhage at the site of the aspiration during EUS (frequency 1.3%: 95% CI [0%, 2.8%]). The bleeding manifested as an expanding echopoor region adjacent to the sampled lesion. No clinically recognizable sequela arose from the bleeding. All patients were treated with a short course of antibiotics and outpatient observation. Preprocedure coagulation and platelet assessment did not predict which patients were at risk for this complication. CONCLUSION: Acute extraluminal hemorrhage occurring during EUS-guided FNA is a rare complication with a characteristic ultrasound appearance. Recognition of this event might be important to allow the endoscopist to terminate the procedure and thereby minimize the potential for more serious bleeding.

Acute Disease↗
PubMed2001

Impact of EUS-guided fine-needle aspiration on lymph node staging in patients with esophageal carcinoma.

BACKGROUND: Preoperative identification of lymph node metastases associated with esophageal carcinoma may influence treatment. EUS is the most accurate method for locoregional staging of these tumors. The impact of EUS-guided fine-needle aspiration (EUS-FNA) on lymph node staging in esophageal carcinoma is unclear. METHODS: From May 1996 to May 1999, 74 patients with esophageal carcinoma underwent preoperative EUS. After October 1998 EUS-guided FNA was performed on nonperitumoral lymph nodes greater than 5 mm in width. The results of EUS with and without FNA were retrospectively reviewed and compared. Final diagnosis was based on surgical results or EUS-guided FNA malignant cytology. Ten of the 74 patients had to be excluded for lack of lymph node stage confirmation. Final diagnosis was obtained in the remaining 64 patients (33 from the EUS only group and 31 from the EUS-FNA group). RESULTS: The results of EUS versus EUS-FNA for lymph node staging were sensitivity 63% versus 93% (p = 0.01), specificity 81% versus 100% (not significant), and accuracy 70% versus 93% (p = 0.02), respectively. Complications comprised 1 patient who developed self-limited bleeding after dilation that did not preclude completion of the EUS (1%, 95% CI [0%, 7%]). CONCLUSIONS: EUS-FNA is more sensitive and accurate than EUS alone for preoperative staging of locoregional and celiac lymph nodes associated with esophageal carcinoma. EUS-FNA of nonperitumoral lymph nodes in patients with esophageal carcinoma is safe and should be routinely performed when treatment decisions will be affected by nodal stage.

Adenocarcinoma↗
PubMed2001

EUS-guided fine-needle aspiration combined with flow cytometry and immunocytochemistry in the diagnosis of lymphoma.

BACKGROUND: Limited information is available regarding the use of EUS-guided fine-needle aspiration (EUS-FNA) in the diagnosis of lymphoproliferative disorders. The aim of this study was to evaluate the yield of this technique in the primary diagnosis of lymphoma. METHODS: The records were reviewed of 38 consecutive patients with GI lesions and/or enlarged lymph nodes identified on imaging studies that raised a suspicion of lymphoma who underwent EUS-FNA of lymph nodes or the gut wall. Final diagnosis was based on clinical follow-up, imaging studies, or surgical findings. RESULTS: Twenty-three patients with lymphoma and 15 patients with benign disease or reactive lymphadenopathy were identified. The overall sensitivity, specificity, and accuracy of EUS-FNA cytology with flow cytometry/immunocytochemistry (FC/IC) for the diagnosis of lymphoma were, respectively, 74%, 93%, and 81%. When comparing patients who had EUS-FNA with FC/IC versus those who had EUS-FNA without FC/IC, sensitivity was 86% versus 44% (p = 0.04), specificity was 100% versus 90% (not significant), and accuracy was 89% versus 68% (not significant). CONCLUSION: EUS-FNA can provide cytology specimens diagnostic for lymphoma. Selective use of FC/IC in patients with suspected lymphoma improves the yield of EUS-FNA and may guide diagnostic evaluation and treatment decisions.

Adult↗
PubMed2001

Initial experience with a steerable, phased vector array ultrasound catheter in the GI tract.

BACKGROUND: EUS requires a significant capital outlay. The ability to perform high-resolution phased array scanning and Doppler interrogation by using a catheter that interfaces with a standard US console could increase the accessibility of EUS. Recently, an electronic phased-array US catheter was developed for intracardiac use. To date, this technology has not been applied to the GI tract. The aim of this study is to determine the feasibility and imaging characteristics of a new phased array scanning US catheter in the GI tract. METHODS: Swine were placed under general anesthesia. This study used a 100 cm, 10F, torquable catheter with 4-way tip deflection to greater than 90 degrees. The catheter tip houses a phased vector array transducer with variable frequency (5.5-10 MHz) and variable focal distance. It has pulsed/color and power Doppler capability. The probe was passed through a therapeutic flexible sigmoidoscope into the upper GI tract. Acoustic coupling was achieved via a condom filled with water or by gastric water infusion. Needle visualization experiments were performed with a second endoscope (also passed per oral) with a standard EUS-guided fine needle aspiration needle. RESULTS: Acoustic coupling was easily achieved. Resolution of the GI wall into characteristic layers (esophagus 5, stomach 7) was demonstrated. At 5.5 MHz, tissue resolution and Doppler imaging were excellent to greater than 10 cm from the transducer. A 22-gauge EUS-guided fine needle aspiration needle was easily visualized at depth greater than 4 cm. Flow in gastric, hepatic, and pancreatic parenchymal vessels approximately 1 mm diameter was visualized by using power and color Doppler. CONCLUSIONS: This 10F array US catheter is capable of high-resolution two-dimensional imaging of the gut wall as well as high-quality Doppler imaging. The Doppler capabilities of this equipment may have new GI applications.

Animals↗
PubMed2001

A prospective study of EUS-guided celiac plexus neurolysis for pancreatic cancer pain.

BACKGROUND: Celiac plexus neurolysis, a chemical splanchnicectomy of the celiac plexus, is used to treat pain caused by pancreatic cancer. Most commonly, celiac plexus neurolysis is performed percutaneously under CT or fluoroscopic guidance, but can also be performed with EUS. The aim of this study was to prospectively assess the efficacy of EUS celiac plexus neurolysis in the management of pain caused by pancreatic cancer. METHODS: In this prospective study conducted in a community-based referral hospital, 58 patients with painful and inoperable pancreatic cancer were evaluated at 8 observation points before and after EUS celiac plexus neurolysis for up to 6 months. The following data were collected: age, gender, tumor location, vascular invasion, adjuvant therapy, and laboratory tests including prothrombin time, and complete blood counts were obtained at baseline (before EUS celiac plexus neurolysis); pain scores, morphine use, and adjuvant therapy were assessed at each observation. RESULTS: Pain scores were lower (p = 0.0001) 2 weeks after EUS celiac plexus neurolysis, an effect that was sustained for 24 weeks when adjusted for morphine use and adjuvant therapy. Forty-five of the 58 patients (78%) experienced a decline in pain scores after EUS celiac plexus neurolysis. Chemotherapy with and without radiation also decreased pain after EUS celiac plexus neurolysis (p = 0.002). Procedure-related transient abdominal pain was noted in 5 patients; there were no major complications. CONCLUSIONS: EUS celiac plexus neurolysis is safe and controls pain caused by unresectable pancreatic cancer.

Aged↗
PubMed2001

A cost analysis of endoscopic ultrasound in the evaluation of pancreatic head adenocarcinoma.

OBJECTIVE: Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) biopsy of nonperitumoral (NPT) lymph nodes (LN) can be helpful in preoperative staging of pancreatic head adenocarcinoma. The economic impact of this staging strategy has not yet been described. The aim of this study was to apply a decision analysis model to compare the costs of three approaches to the management of nonmetastatic pancreatic head adenocarcinoma: EUS FNA versus CT-guided FNA versus surgery. A cost minimization approach was employed, as viewed from the perspective of the payer. METHODS: A decision analysis model was designed using DATA Version 3.5, taking the entry criteria as "resectable" pancreatic head adenocarcinoma as determined by helical CT. Detection of metastatic NPT LN on FNA signified unresectability and obviated the need for surgery. Baseline probabilities were varied through plausible ranges using sensitivity analysis. Cost inputs were based on Medicare professional plus facility fees. The endpoint was cost of management per patient. RESULTS: EUS FNA was the least costly strategy ($15,938) compared with CT FNA ($16,378) and surgery ($18,723). Sensitivity analysis revealed that EUS FNA remained the least costly option provided the frequency of NPT LN involvement was >4%; below this value, surgery became the least costly. CONCLUSIONS: EUS FNA is the least costly staging strategy in the workup of patients with nonmetastatic pancreatic head adenocarcinoma primarily because of confirmation of NPT LN involvement avoiding unnecessary surgery. These results support performing EUS in patients whose tumors are thought to be resectable on helical CT to enhance NPT LN assessment.

Adenocarcinoma↗
PubMed2001

Prospective comparison of endoscopy patient satisfaction surveys: e-mail versus standard mail versus telephone.

OBJECTIVES: The dramatic growth of the Internet holds potential for use in survey distribution. Comparisons of electronic mail (e-mail) to traditional survey techniques are lacking. We compared standard mail, telephone, and e-mail modes of endoscopy satisfaction survey administration with respect to response rate, timeliness of response, response content, and cost-efficiency of responses. METHODS: An endoscopy satisfaction questionnaire consisting of seven core items from the modified Group Health Association of America-9 survey was distributed to patients after routine outpatient endoscopy. Patients were randomized to receive the questionnaire by standard mail, telephone, or e-mail. Response rates and findings in the three groups were compared. The "nonresponders" to the standard mail and e-mail surveys were subsequently contacted by telephone to determine their level of satisfaction. RESULTS: The phone survey response rate (90%) was higher than e-mail (70%) or standard mail (85%), although e-mail was the most cost-efficient mode of survey delivery. There was no significant difference in satisfaction scores among the three groups. Nonresponders were significantly more satisfied than "responders." CONCLUSIONS: A survey technique utilizing e-mail with subsequent follow-up by telephone to nonresponders appears to be the most cost-efficient way to deliver a questionnaire. The satisfaction levels of the responders may underestimate the overall satisfaction of the population being surveyed.

Colonoscopy↗
PubMed2001

Evaluation of mediastinal lymphadenopathy with endoscopic US-guided fine-needle aspiration biopsy.

PURPOSE: To evaluate the safety and accuracy of endoscopic ultrasonography (US)-guided fine-needle aspiration biopsy (FNAB) of lymph nodes in the paratracheal, aortopulmonic, subcarinal, and posterior mediastinal regions. MATERIALS AND METHODS: Eighty-six consecutive patients with mediastinal lymphadenopathy who did not have a primary gastrointestinal neoplasm were examined. In 29 patients, endoscopic US-guided FNAB of mediastinal lymphadenopathy was performed as a component of staging non-small cell lung cancer (NSCLC); in the remaining 57 patients, it was performed to obtain a primary diagnosis. Final diagnosis was based on clinical follow-up, cytologic, and/or surgical results. RESULTS: In 82 patients in whom a final diagnosis was available, the sensitivity, specificity, accuracy, negative predictive value, and positive predictive value of endoscopic US-guided FNAB in distinguishing benign from malignant mediastinal lymph nodes were 96%, 100%, 98%, 94%, and 100%, respectively. In those patients who underwent staging of NSCLC, endoscopic US-guided FNAB had superior mediastinal lymph node staging accuracy compared with endoscopic US alone (79%) and CT alone (79%) (P =.01). The results of endoscopic US-guided FNAB prompted a change to nonsurgical management in 66 (80%) of 82 patients who underwent the procedure. One minor complication, postprocedural fever that resolved with oral antibiotics, occurred (1%; 95% CI: 0%, 6%). CONCLUSION: Endoscopic US-guided FNAB is accurate and safe for biopsy of mediastinal lymph nodes to stage NSCLC, establish a primary diagnosis, or examine patients with prior inconclusive biopsy results.

Adolescent↗