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Michael V Sivak

Publications and source records attributed to Michael V Sivak.

At least 19 recordsLinked to original sources
PubMed2006

Endoscopic ultrasonography and prognosis of esophageal cancer.

BACKGROUND & AIMS: Endoscopic ultrasonography (EUS) staging is used for management of esophageal cancer, but its effect on the outcome of patients is unknown. Our aim was to study the association of receipt of EUS and overall survival in a cohort of patients with esophageal cancer. METHODS: All persons 65 years or older who were diagnosed with esophageal cancer between January 1994 and December 1999 in the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database were identified. Relevant demographic, cancer-specific information and EUS procedural information were extracted. RESULTS: Two thousand eight hundred thirty patients with esophageal cancer (48% squamous cell cancer) were eligible for analysis. Only 303 (10.7%) patients underwent a EUS examination. Patients who had EUS evaluation were more likely to undergo esophageal resection (21.1% vs 14.7%, P = .01) and more likely to have received adjuvant therapy (11.2% vs 6.7%, P = .008). When adjusted for age at diagnosis, race, gender, comorbidity, histology, and tumor stage, receipt of EUS was associated with a reduced risk of death (relative hazard, 0.594; 95% confidence interval, 0.52-0.68; P = .001). CONCLUSIONS: Undergoing EUS in patients with esophageal cancer is independently associated with improved survival, possibly because of improved stage-appropriate management such as use of adjuvant therapy and surgical resection.

Adenocarcinoma↗
PubMed2006

Primary care physician attitudes toward endoscopic screening for GERD symptoms and unsedated esophagoscopy.

BACKGROUND: Current guidelines recommend consideration of screening patients with chronic GERD for Barrett's esophagus (BE). Unsedated esophagoscopy (UE) is a less costly alternative to standard EGD for identifying BE. The aim of this study was to determine the indications for EGD referral, the barriers to screening, and the interest in performing UE. METHODS: A one-page survey was mailed to a random sample of 500 family practitioners and 500 internists. This sample was obtained from the American Academy of Family Physicians and American Society of Internal Medicine (500 from each organization). RESULTS: The overall response rate was 54%. The majority (78%) refer more than 50% of their GERD patients for EGD; however, 34% also refer more than 10% of their patients for barium studies. Primary care physicians cited alarm symptoms, refractory symptoms, and chronicity and severity of symptoms as the major indications for referral for EGD. Gender, age, obesity, and tobacco use were cited less frequently. Cost of endoscopy, poor patient acceptance, and lack of evidence were the most common reasons cited for not referring for EGD. A majority of respondents (62%) indicated that the availability of UE would increase referral for the procedure, and 52% would be willing to perform UE in their office. CONCLUSIONS: Severe, refractory, and chronic symptoms are the primary reasons for endoscopic referral from primary care physicians who manage patients with GERD. Other risk factors for BE, such as gender and age, do not appear to be important determinants for endoscopic referral. Further evaluation of UE as a mechanism to increase screening for BE in primary care patients is merited.

Attitude of Health Personnel↗
PubMed2005

In vivo optical coherence tomography imaging of the pancreatic and biliary ductal system.

BACKGROUND: In vivo optical coherence tomography (OCT) imaging has not yet been applied to the pancreatic ductal system. The aim of this study was to obtain in vivo OCT images of dog pancreatic and biliary ducts, and to correlate the images with histology. METHODS: Images of dog pancreatic and biliary ducts were obtained by using an in vivo OCT probe introduced through the respective papillary orifices. Each duct was imaged in multiple locations, and the site of imaging was marked with injected India ink. After imaging, the dogs were euthanized, and the pancreaticobiliary system was harvested. Histologic cross sections were correlated with in vivo OCT images by measuring the structures seen on in vivo OCT images and correlating them with structures seen on corresponding histology slides that contained India ink. OBSERVATIONS: Eighteen pairs of in vivo OCT images and histology slides from the bile duct and the pancreatic duct were obtained from 5 dogs. The entire duct wall could be visualized. A low reflective in vivo OCT layer corresponding to the epithelium could be discerned on many images. The bile duct showed a more complex architecture and had greater variations within the reflective OCT layers, possibly because of greater cellularity within the lamina propria. Nuclei within cells could not be identified, and structures adjacent to the ducts could not be imaged. CONCLUSIONS: In vivo OCT is capable of imaging the pancreaticobiliary ductal system and of identifying the epithelial layer. Because of limited depth of imaging (320-845 micron), OCT is unlikely to serve the purpose of tumor staging.

Animals↗
PubMed2005

Accuracy of endoscopic optical coherence tomography in the detection of dysplasia in Barrett's esophagus: a prospective, double-blinded study.

BACKGROUND: Endoscopic optical coherence tomography (EOCT) is a high-resolution, cross-sectional tissue-imaging technique that provides microscopic morphologic information. EOCT should detect dysplasia in Barrett's epithelium, but this has not been established in a prospective blinded study. This study evaluated the accuracy of EOCT for the diagnosis and the exclusion of dysplasia in patients with Barrett's esophagus. METHODS: A 2.4-mm diameter EOCT probe was modified for use with a cap-fitted, two-channel endoscope. Pairs of EOCT image streams and jumbo biopsy specimens were obtained. Endoscopy/EOCT procedures were performed by 4 endoscopists who separately reviewed the EOCT digital images for the absence or the presence of dysplasia (low grade, high grade, or cancer) for each biopsy specimen obtained. The endoscopists were blinded to the interpretation of the pathology. An experienced pathologist blinded to the endoscopic/EOCT findings evaluated each biopsy for the absence or the presence of dysplasia. The setting of the study was a major academic medical center. Adult patients with documented Barrett's esophagus greater than 2 cm were included in the study. The main outcome measurement was the accuracy of EOCT in the detection of dysplasia in patients with Barrett's esophagus. RESULTS: A total of 314 usable EOCT image stream/biopsy pairs were obtained in 33 patients. By using histology as the standard, the performance of EOCT was sensitivity, 68%; specificity, 82%; positive predictive value, 53%; negative predictive value, 89%; and diagnostic accuracy, 78%. Diagnostic accuracy for the 4 endoscopists ranged from 56% to 98%. Limitations of the study were the variability in endoscopists' accuracy rates, difficulty in real-time interpretation, and the need for refined criteria of dysplasia by EOCT imaging. CONCLUSIONS: The current EOCT system has an accuracy of 78% for the detection of dysplasia in patients with Barrett's esophagus. EOCT could be used to target biopsies to areas of Barrett's epithelium with a higher probability for the presence of dysplasia. However, further modifications, including increased resolution and identification of further potential OCT characteristics of dysplasia, are needed before EOCT can be used clinically.

Adult↗
PubMed2005

Correlation of endoscopic optical coherence tomography with histology in the lower-GI tract.

BACKGROUND: Optical coherence tomography (OCT), a noninvasive optical imaging technique, provides high-resolution cross-sectional images of tissue microstructure. We developed a system for real-time endoscopic OCT (EOCT) of the human GI tract. During clinical trials, the structure of mucosa and submucosa, glands, blood vessels, pits, villi, and crypts was observed in a range of GI organs. Although EOCT images are thought to accurately depict actual histologic features, there are few data to support this assumption. Therefore, the present study correlated images acquired with an EOCT imaging system in vitro to corresponding histologic sections. METHODS: EOCT images were obtained of fresh specimens of ileum, colon, and rectum that then were fixed in formalin and were processed for microscopic evaluation by using standard methods. The thickness of mucosa and of submucosa was determined for both EOCT images and histologic slides. RESULTS: The first hyper-reflective layer in the EOCT images was identified as mucosa. A close correlation (R 2=0.84) was observed between EOCT and histology. Furthermore, the submucosa and the muscularis propria could be identified as the next deepest hyporeflective band and a hyper-reflective layer, respectively, in EOCT images. The submucosa was found to be more compressible than mucosa, and its EOCT appearance was dependent on its content of adipose tissue. CONCLUSIONS: EOCT provides images that precisely correlate with the histologic structure of the mucosa and the submucosa of the GI tract.

Colon↗
PubMed2005

The changing landscape of practice patterns regarding unsedated endoscopy and propofol use: a national Web survey.

BACKGROUND: Lower reimbursements for endoscopic procedures and increasing demand for screening endoscopy over the past decade have spurred efforts to increase efficiency in the performance of endoscopic procedures. Two dichotomous approaches have emerged: (1) unsedated endoscopy and (2) propofol sedation. The aim was to determine national practice patterns of unsedated endoscopy and propofol sedation, and to assess endoscopists' attitudes toward unsedated screening with an electronic survey. METHODS: A short survey was developed and then was converted to a Web-based format. All national members of the American Society for Gastrointestinal Endoscopy (ASGE) were invited via electronic mail (e-mail) to participate. Survey data were collected electronically. RESULTS: Two e-mails elicited responses to the Web survey from 18% (724) of national ASGE members contacted, within 2 weeks. Of the respondents, 45% do not routinely offer unsedated EGD and colonoscopy, and only 15% of those respondents plan to incorporate unsedated endoscopy into their practice in the next year. Of the 55% who currently perform unsedated endoscopy, 85% do no more than 25 unsedated procedures per year. Lack of patient acceptance was the most common reason cited for not offering unsedated endoscopy. Most endoscopists felt that the availability of unsedated esophagoscopy or colonoscopy would not significantly increase screening for Barrett's esophagus or colonic polyps/colorectal cancer, respectively. Routine use of propofol sedation for EGD, colonoscopy, and ERCP/EUS was reported by 19%, 22%, and 19%, respectively. Community practitioners were more likely to use propofol than those at academic centers (p < 0.0002 for all). Of those not currently using propofol, 43% plan to incorporate it into their practice within the next year. Over 70% of respondents would themselves choose to be sedated for routine endoscopic procedures. CONCLUSIONS: Electronic surveys allow for rapid distribution and data collection but suffer from a limited response rate. The survey suggests that unsedated endoscopy has limited acceptance in the United States, and, without a major intervention that affects endoscopists' attitudes, its use is not likely to increase significantly. Unsedated endoscopy will not have a great impact on endoscopic screening. In contrast, propofol sedation has already gained acceptance in the community, and the routine use of propofol in endoscopy units will likely increase in the future.

Anesthetics, Intravenous↗
PubMed2005

The yield of bleeding scans in acute lower gastrointestinal hemorrhage.

GOALS/BACKGROUND: Previous studies have demonstrated low yield and conflicting results as to the ability of technetium-99m labeled red blood cell (TRBC) scintigraphy to accurately localize the site of bleeding in acute lower gastrointestinal hemorrhage. Our objective was to evaluate the accuracy of TRBC scintigraphy in clinical day-to-day practice at our institution and to determine predictors of a positive test. METHODS: A retrospective medical records review of all patients who underwent TRBC scintigraphy over a 5-year period was conducted at a single academic medical center. The site of bleeding found on TRBC scintigraphy was correlated with the endoscopic, angiographic, surgical, and pathologic findings in each patient. RESULTS: A total of 127 scans were performed in 115 patients. Forty-nine scans were positive (39%) and 78 were negative (61%). Forty-two patients had further evaluation after a positive scan, and the bleeding site was confirmed to be accurate in 20 of 42 patients (48%). A contradictory bleeding site was found in 5 of 49 positive scans (10%). Patients transfused greater than 2 units of packed red blood cells within 24 hours preceding the TRBC scan were twice as likely to have a positive scan (64%) than those transfused 2 units or less (32%) (P = 0.002). Multivariate analysis demonstrated that the number of units of blood transfused within 24 hours prior to the TRBC scan and the lowest recorded hematocrit were significantly different between patients with positive and negative scans. There was no difference in the rate of endoscopy between patients with a positive or negative scan result. CONCLUSIONS: TRBC scintigraphy has a relatively low yield in the evaluation of acute lower gastrointestinal bleeding. Objective selection criteria such as number of units of packed red blood cells transfused prior to obtaining the scan may increase the overall yield.

Acute Disease↗
PubMed2004

Computed tomographic colonography (virtual colonoscopy): a multicenter comparison with standard colonoscopy for detection of colorectal neoplasia.

CONTEXT: Conventional colonoscopy is the best available method for detection of colorectal cancer; however, it is invasive and not without risk. Computed tomographic colonography (CTC), also known as virtual colonoscopy, has been reported to be reasonably accurate in the diagnosis of colorectal neoplasia in studies performed at expert centers. OBJECTIVE: To assess the accuracy of CTC in a large number of participants across multiple centers. DESIGN, SETTING, AND PARTICIPANTS: A nonrandomized, evaluator-blinded, noninferiority study design of 615 participants aged 50 years or older who were referred for routine, clinically indicated colonoscopy in 9 major hospital centers between April 17, 2000, and October 3, 2001. The CTC was performed by using multislice scanners immediately before standard colonoscopy; findings at colonoscopy were reported before and after segmental unblinding to the CTC results. MAIN OUTCOME MEASURES: The sensitivity and specificity of CTC and conventional colonoscopy in detecting participants with lesions sized at least 6 mm. Secondary outcomes included detection of all lesions, detection of advanced lesions, possible technical confounders, participant preferences, and evidence for increasing accuracy with experience. RESULTS: A total of 827 lesions were detected in 308 of 600 participants who underwent both procedures; 104 participants had lesions sized at least 6 mm. The sensitivity of CTC for detecting participants with 1 or more lesions sized at least 6 mm was 39.0% (95% confidence interval [CI], 29.6%-48.4%) and for lesions sized at least 10 mm, it was 55.0% (95% CI, 39.9%-70.0%). These results were significantly lower than those for conventional colonoscopy, with sensitivities of 99.0% (95% CI, 97.1%->99.9%) and 100%, respectively. A total of 496 participants were without any lesion sized at least 6 mm. The specificity of CTC and conventional colonoscopy for detecting participants without any lesion sized at least 6 mm was 90.5% (95% CI, 87.9%-93.1%) and 100%, respectively, and without lesions sized at least 10 mm, 96.0% (95% CI, 94.3%-97.6%) and 100%, respectively. Computed tomographic colonography missed 2 of 8 cancers. The accuracy of CTC varied considerably between centers and did not improve as the study progressed. Participants expressed no clear preference for either technique. CONCLUSIONS: Computed tomographic colonography by these methods is not yet ready for widespread clinical application. Techniques and training need to be improved.

Colonography, Computed Tomographic↗
PubMed2004

Endoscopic management of adenoma of the major duodenal papilla.

BACKGROUND: It is well established that adenoma of the major duodenal papilla has a potential for malignant transformation. Standard treatment has been surgical (duodenotomy/local resection, pancreaticoduodenectomy). Endoscopic management is described, but there is no established consensus regarding the approach to papillectomy or the need for surveillance. This study describes endoscopic management and long-term follow-up of papillary tumors by 4 groups of expert pancreaticobiliary endoscopists. METHODS: Consecutive patients with papillary tumors referred to 4 pancreaticobiliary endoscopy centers for evaluation for endoscopic papillectomy were reviewed. For each patient, an extensive questionnaire was completed, which included 19 preoperative and 15 postoperative data points. A total of 103 patients (53 women, 50 men, age range 24-93) who underwent attempted endoscopic resection were included. Of these, 72 had sporadic adenoma, and the remaining patients had familial adenomatous polyposis, including Gardner's variant. Presenting symptoms were jaundice/cholangitis/pain (n=59), pancreatitis (n=18), and bleeding (n=12). Twenty-six patients were asymptomatic. RESULTS: Endoscopic treatment was successful, long term, in 83 patients (80%) and failed (initial failure or recurrent tumor) in 20 (20%) patients. Success was significantly associated with older age (54.7 [16.6] vs. 46.6 [21.7] years; p=0.08) and smaller lesions (21.1 [8.3] vs. 29.7 [7.2] mm; p<0.0001). Success rate was higher for sporadic lesions compared with genetically determined lesions (63 of 72 [86%] vs. 20 of 31 [67%]; p=0.02). There were 10 initial failures, which was more common for sporadic lesions (7 of 10). The overall success rate for papillectomy was similar in patients who had adjuvant thermal ablation (81%) compared with those who did not (78%). However, recurrence (n=10) was more common in the former group (9 of 10, [90%]; p=0.22). Complications (n=10) included acute pancreatitis (n=5), bleeding (n=2), and late papillary stenosis (n=3). Acute pancreatitis was more common in patients who did not have pancreatic duct stents placed (17% vs. 3.3%). Papillary stenosis was more frequent without short-term pancreatic duct stent placement (15.4% vs. 1.1%), although the difference was not statistically significant, because this complication was infrequent. CONCLUSIONS: Endoscopic treatment of papillary adenoma in selected patients appears to be highly successful. The majority can undergo complete resection after ERCP. In expert hands, complications are infrequent and may be avoided by routine placement of a pancreatic duct stent.

Adenoma↗
PubMed2004

Sphincter of Oddi manometry does not predispose to post-ERCP acute pancreatitis.

BACKGROUND: Sphincter of Oddi manometry is helpful in selecting patients with sphincter of Oddi dysfunction who will respond to sphincterotomy. However, studies have shown that sphincter of Oddi manometry is associated with a high risk of post-procedure pancreatitis. The primary objective of this study was to evaluate the safety of sphincter of Oddi manometry in patients with sphincter of 2Oddi dysfunction. The secondary objective was to determine the risk factors for post-ERCP pancreatitis in patients with sphincter of Oddi dysfunction. METHODS: Data were collected retrospectively for 268 patients who had elective ERCP performed at 3 tertiary care medical centers between 1996 and 2000. Consecutive patients with suspected sphincter of Oddi dysfunction formed the case group; the control group consisted of patients with bile duct stone. The case group was further subclassified into group A, patients who underwent sphincter of Oddi manometry followed by immediate ERCP, and group B, patients who had ERCP without manometry. The rate of post-ERCP acute pancreatitis was compared between case and control groups. RESULTS: Twenty-seven percent of patients in the case group with suspected sphincter of Oddi dysfunction developed acute pancreatitis compared with 3.2% of patients in the control group with bile duct stone (p<0.001). There was no significant difference in the rate of acute pancreatitis in patients with sphincter of Oddi dysfunction who underwent sphincter of Oddi manometry and ERCP compared with patients with sphincter of Oddi dysfunction who had ERCP without sphincter of Oddi manometry (odds ratio 0.72: 95% CI[0.08, 9.2]). Multivariable logistic regression analysis showed that biliary sphincterotomy (p=0.006) and pancreatography (p=0.03) were independent predictors of acute pancreatitis. CONCLUSIONS: Patients with suspected sphincter of Oddi dysfunction are at higher risk of post-ERCP acute pancreatitis. Sphincter of Oddi manometry by itself does not appear to predispose to this complication.

Acute Disease↗
PubMed2004

Acute pancreatitis after EUS-guided FNA of solid pancreatic masses: a pooled analysis from EUS centers in the United States.

BACKGROUND: The aim of this study was to determine the frequency and the severity of pancreatitis after EUS-guided FNA of solid pancreatic masses. A survey of centers that offer training in EUS in the United States was conducted. METHODS: A list of centers in which training in EUS is offered was obtained from the Web site of the American Society for Gastrointestinal Endoscopy. Designated program directors were contacted via e-mail. The information requested included the number of EUS-guided FNA procedures performed for solid pancreatic masses, the number of cases of post-procedure pancreatitis, and the method for tracking complications. For each episode of pancreatitis, technical details were obtained about the procedure, including the location of the mass, the type of fine needle used, the number of needle passes, and the nature of the lesion. RESULTS: Nineteen of the 27 programs contacted returned the questionnaire (70%). In total, 4909 EUS-guided FNAs of solid pancreatic masses were performed in these 19 centers over a mean of 4 years (range 11 months to 9 years). Pancreatitis occurred after 14 (0.29%): 95% CI[0.16, 0.48] procedures. At two centers in which data on complications were prospectively collected, the frequency of acute pancreatitis was 0.64%, suggesting that the frequency of pancreatitis in the retrospective cohort (0.26%) was under-reported (p=0.22). The odds that cases of pancreatitis would be reported were 2.45 greater for the prospective compared with the retrospective cohort (95% CI[0.55, 10.98]). The median duration of hospitalization for treatment of pancreatitis was 3 days (range 1-21 days). The pancreatitis was classified as mild in 10 cases, moderate in 3, and severe in one; one death (proximate cause, pulmonary embolism) occurred after the development of pancreatitis in a patient with multiple comorbid conditions. CONCLUSIONS: EUS-guided FNA of solid pancreatic masses is infrequently associated with acute pancreatitis. The procedure appears to be safe when performed by experienced endosonographers. The frequency of post EUS-guided FNA pancreatitis may be underestimated by retrospective analysis.

Acute Disease↗
PubMed2004

Does prophylactic pancreatic stent placement reduce the risk of post-ERCP acute pancreatitis? A meta-analysis of controlled trials.

BACKGROUND: Impaired drainage of the pancreatic duct is one of the possible triggers for post-ERCP acute pancreatitis. The aim of this meta-analysis was to determine whether temporary stent placement across the main pancreatic-duct orifice lowers the frequency of post-ERCP acute pancreatitis in patients at high risk for this complication. METHODS: Two reviewers systematically identified prospective studies that (1) compared the risk of post-ERCP acute pancreatitis in patients with pancreatic stent placement vs. no stent placement and (2) included patients at high risk of developing this complication. Studies were assessed for methodologic quality and variations in execution and design. Frequency and severity of post-ERCP acute pancreatitis were the primary outcomes evaluated. RESULTS: Five trials involving 481 patients were selected. Of the 481, 55 (11.4%) patients developed pancreatitis after ERCP. Patients in the no stent group had 3-fold higher odds of developing pancreatitis compared with the stent group (15.5% vs. 5.8%; OR 3.2: 95% CI[1.6, 6.4]). Number needed to treat analysis showed that one in every 10 patients (95% CI[6,18]) could be expected to benefit from pancreatic-duct stent placement. CONCLUSIONS: Prophylactic temporary stent placement across the main pancreatic-duct orifice reduces the risk of post-ERCP acute pancreatitis in patients at risk for developing this complication.

Acute Disease↗
PubMed2004

An international survey of the clinical practice of EUS.

BACKGROUND: No comparative information exists regarding clinical variations in EUS practice patterns among American and international endosonographers. METHODS: Eligible attendees of the XIIIth International Symposium on EUS, October 4-6 2002, New York, New York, were asked to complete a 2-page survey questionnaire on clinical practice of EUS. RESULTS: A total of 191 of 391 eligible attendees (48.9%) participated in the survey (110 from the United States, 81 from 30 different countries). The mean age of participants was 40.5 (10.6) years, and 171 (89.5%) were men. A total of 102 endosonographers (53.4%) were in academic practice. The majority (150, 78.5%) also performed ERCP. Seventy-eight (40.8%) had performed EUS for more than 5 years and 21 (11%) for less than 1 year. Only 36 (18.8%) had more than 6 months of dedicated hands-on EUS training, and more than a third of the respondents learned to perform EUS by observing others or they were self-taught. Compared with respondents from the United States, relatively fewer international respondents were performing open-access EUS, pancreatobiliary EUS procedures, and interventions such as EUS-guided FNA and celiac plexus neuralysis. CONCLUSIONS: This survey provides insight into the status of EUS as practiced in the United States and internationally. Although it appears that over the last decade EUS has become disseminated fairly uniformly on a global basis, a lack of consistent training standards and also inadequate opportunities for EUS training remain important areas of concern.

Adult↗
PubMed2004

Success and shortcomings of a clinical care pathway in the management of acute nonvariceal upper gastrointestinal bleeding.

OBJECTIVES: Acute nonvariceal upper gastrointestinal (GI) bleeding is the most common medical emergency encountered by gastroenterologists resulting in high patient morbidity and cost. We sought to establish if a GI bleeding clinical care pathway could improve the quality and cost effectiveness of inpatient medical care. METHODS: A disease management program for acute upper GI bleeding was established. Length of stay, time to endoscopy, utilization of potentially unnecessary radiological tests, acid suppression, and cost of care were compared between patients pre- and postinitiation of GI bleeding pathway guidelines. RESULTS: The instituted GI bleeding management program significantly reduced the use of intravenous H2-blockade from 65.3% to 47.7% (p = 0.002). The use of radiological tests, time to endoscopy, and length of hospital of stay were unchanged. There was a trend toward a reduction in total cost and variable direct cost per patient admitted with acute upper GI bleeding, from $5,381 to $4,627 and from $2,269 to $1,952, respectively. CONCLUSION: A clinical care pathway may affect the management of acute upper GI bleeding and reduce costs. However, there are significant limitations and barriers to the overall effectiveness of such a pathway in actual clinical practice.

Acute Disease↗
PubMed2003

Prediction of outcome in acute lower-gastrointestinal haemorrhage based on an artificial neural network: internal and external validation of a predictive model.

BACKGROUND: Models based on artificial neural networks (ANN) are useful in predicting outcome of various disorders. There is currently no useful predictive model for risk assessment in acute lower-gastrointestinal haemorrhage. We investigated whether ANN models using information available during triage could predict clinical outcome in patients with this disorder. METHODS: ANN and multiple-logistic-regression (MLR) models were constructed from non-endoscopic data of patients admitted with acute lower-gastrointestinal haemorrhage. The performance of ANN in classifying patients into high-risk and low-risk groups was compared with that of another validated scoring system (BLEED), with the outcome variables recurrent bleeding, death, and therapeutic interventions for control of haemorrhage. The ANN models were trained with data from patients admitted to the primary institution during the first 12 months (n=120) and then internally validated with data from patients admitted to the same institution during the next 6 months (n=70). The ANN models were then externally validated and direct comparison made with MLR in patients admitted to an independent institution in another US state (n=142). FINDINGS: Clinical features were similar for training and validation groups. The predictive accuracy of ANN was significantly better than that of BLEED (predictive accuracy in internal validation group for death 87% vs 21%; for recurrent bleeding 89% vs 41%; and for intervention 96% vs 46%) and similar to MLR. During external validation, ANN performed well in predicting death (97%), recurrent bleeding (93%), and need for intervention (94%), and it was superior to MLR (70%, 73%, and 70%, respectively). INTERPRETATION: ANN can accurately predict the outcome for patients presenting with acute lower-gastrointestinal haemorrhage and may be generally useful for the risk stratification of these patients.

Acute Disease↗
PubMed2003

Long-term follow-up of patients with clinically indeterminate suspicion of pancreatic cancer and normal EUS.

BACKGROUND: EUS often is performed because of a clinical suspicion of pancreatic cancer when the results of other noninvasive diagnostic tests are indeterminate. The aim of this study was to determine the true negative predictive value of a normal EUS in a cohort of patients with an indeterminate suspicion of pancreatic cancer by obtaining long-term follow-up information. METHODS: Patients referred for EUS of the pancreas for the following indications were identified: elevated carbohydrate-associated antigen (CA 19-9) without other definitive evidence of pancreatic cancer, subtle abnormalities on CT of the pancreas, and unexplained abdominal pain and/or weight loss. Endoscopy procedure reports, as well as inpatient and outpatient records were obtained. In addition, referring physicians, as well as patients, were contacted to acquire adequate follow-up information. RESULTS: A total of 80 patients were included in the study. Follow-up of at least 6 months was obtained for 76 (95%) patients (mean follow-up 23.9 months). No patient with a normal EUS of the pancreas developed pancreatic cancer or required pancreatic surgery during the follow-up period. One patient in whom a diagnosis of chronic pancreatitis was made by EUS subsequently was found to have pancreatic cancer at surgery. CONCLUSIONS: A normal EUS of the pancreas in the setting of subtle radiologic findings, serologic abnormalities, and/or nonspecific symptoms definitively rules out the presence of pancreatic cancer.

CA-19-9 Antigen↗