RESUMEN
BACKGROUND AND STUDY AIMS: In routine practice, colonoscopy may fail to prevent colorectal cancer (CRC), especially in the proximal colon. A better endoscopic recognition of serrated polyps is important, as this pathway may explain some of the post-colonoscopy cancers. In this study, the endoscopic characteristics of serrated polyps were examined. PATIENT AND METHODS: This was a cross-sectional, single-center study of all consecutive patients referred for elective colonoscopy during 1 year. The endoscopists were familiarized with the detection and treatment of nonpolypoid colorectal lesions. Serrated polyps were classified into high risk serrated polyps, defined as dysplastic or large (≥ 6 mm) proximal nondysplastic serrated polyps, and low risk serrated polyps including the remaining nondysplastic serrated polyps. Advanced colorectal neoplasms were defined as multiple (at least three),≥ 10 mm in size, high grade dysplastic adenomas or CRC. RESULTS: A total of 2309 patients were included (46.1 % men, mean age 58.4 years), of whom 2.5 % (57) had at least one high risk serrated polyp and 13.9 % (322) had at least one advanced neoplasm. Overall, serrated polyps were more often nonpolypoid than adenomas (16.2 % vs. 11.1 %; P = 0.002). In total, 65 high risk serrated polyps were found, of which 43.1 % (28) displayed a nonpolypoid endoscopic appearance. Patients with advanced neoplasms were more likely to have synchronous high risk serrated polyps than patients without advanced neoplasms: OR 3.66 (95 % CI 2.03 - 6.61, P < 0.001). CONCLUSIONS: High risk serrated polyps are frequently nonpolypoid and are associated with synchronous advanced colorectal neoplasms. Advanced colorectal neoplasms may therefore be considered red flags for the presence of high risk serrated polyps. Detection, diagnosis, and treatment of high risk serrated lesions may be important targets to improve the quality of colonoscopic cancer prevention.
Asunto(s)
Pólipos del Colon/diagnóstico , Colonoscopía , Neoplasias Colorrectales/diagnóstico , Pólipos del Colon/patología , Pólipos del Colon/cirugía , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de RiesgoRESUMEN
BACKGROUND AND STUDY AIMS: Endoscopic ultrasound (EUS) in combination with fine-needle aspiration biopsy (FNA) is a highly accurate method for the preoperative staging of esophageal cancer. Its impact on medical decision-making and the cost of care is unknown. This prospective case series was undertaken in order to determine the impact of EUS in combination with FNA on patients' choice of therapy and on the cost of care. PATIENTS AND METHODS: Sixty consecutive patients with esophageal cancer, referred for preoperative EUS staging in a large tertiary-care academic medical center, were enrolled. The accuracy of EUS, the impact of EUS-based staging on the patients' choice of therapy, and costs were studied. RESULTS: The accuracy rates for EUS combined with FNA in tumor and lymph-node staging were 83 % and 89 %, respectively. Twenty-five patients (42 %) had EUS stage I and II and were candidates for curative surgery. Twenty-eight patients (47 %) had stage III, and seven (12 %) had stage IV. All patients with stage I had surgery, while all patients with stage IV had medical therapy. The majority (62 %) of patients with stage II had surgery, while only a minority (25 %) of patients with stage III had surgery. Thirty-six patients (60 %) underwent medical therapy. Patients' medical decisions in favor of surgical or medical therapy correlated strongly with the results of their EUS staging ( P = 0.005), but not with age, sex, or referring physicians (surgeons vs. nonsurgeons). EUS-guided therapy potentially decreased the cost of care by $ 740 424 ($ 12 340/patient) by reducing the number of thoracotomies. CONCLUSIONS: Patients' decisions regarding therapy correlated with their overall tumor staging, suggesting that the information provided by EUS played a significant role in patients' decision-making. The use of EUS in combination with FNA reduces the cost of managing patients with esophageal cancer.
Asunto(s)
Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Biopsia con Aguja Fina/métodos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Endosonografía/métodos , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/terapia , Adenocarcinoma/economía , Anciano , Carcinoma de Células Escamosas/economía , Neoplasias Esofágicas/economía , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Aceptación de la Atención de Salud , Estudios Prospectivos , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND AND STUDY AIMS: Pancreatitis is the most common significant complication of endoscopic retrograde cholangiopancreatography (ERCP). The aim of the present study was to develop a simple scoring system that clinicians can use to predict the risk of post-ERCP pancreatitis. PATIENTS AND METHODS: We analyzed a prospectively assembled database of 1835 ERCP procedures at a single referral hospital. Multivariate logistic regression analysis was performed to identify risk factors for pancreatitis and determine their relative contributions. From these results, a scoring system was constructed. The performance of the scoring system was assessed on the entire procedure database and in selected subgroups. RESULTS: Multivariate analysis yielded four risk factors: pain during the procedure, cannulation of the pancreatic duct (PD), previous post-ERCP pancreatitis, and number of cannulation attempts. Based on the regression model, the scoring system was: 4 points for pain, 3 points for PD cannulation, 2 points for a history of post-ERCP pancreatitis, and 1 - 4 points depending on the number of cannulation attempts. A total score of 1 - 4 points was associated with a low risk of pancreatitis (< 2 %), while a score of 5 - 8 points had an intermediate risk (7 %), and a score of 9 or above had a high risk (28 %). CONCLUSIONS: This simple scoring system may enable clinicians to stratify patients into low-risk, medium-risk, and high-risk groups for the development of post-ERCP pancreatitis. In addition, when patients with suspected sphincter of Oddi dysfunction and patients who underwent minor papilla cannulation were analyzed separately, the scoring system was able to predict accurately the pancreatitis risk of these patients as well.
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Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Pancreatitis/etiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Sistemas de Atención de Punto , Factores de RiesgoRESUMEN
Large bowel obstruction in the terminally ill patient can be difficult to manage. We describe a patient with sigmoid colon obstruction caused by metastatic prostate cancer in the pelvis who required hospitalization because of severe pain and obstructive symptoms. Treatment with an endoscopically placed self-expandable metal stent allowed the patient to have immediate resolution of symptoms and to receive hospice care at home.
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Colonoscopía/métodos , Cuidados Paliativos al Final de la Vida/métodos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/terapia , Cuidados Paliativos/métodos , Neoplasias de la Próstata/patología , Neoplasias del Colon Sigmoide/complicaciones , Neoplasias del Colon Sigmoide/secundario , Sigmoidoscopía/métodos , Stents/normas , Resultado Fatal , Servicios de Atención de Salud a Domicilio , Humanos , Obstrucción Intestinal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Dolor/etiología , RadiografíaRESUMEN
Recent advances in endoscopic mucosal resection of superficial early digestive tract cancers are truly remarkable. The extraordinary long-term outcomes of patients who have been treated with endoscopic mucosal resection have encouraged the widespread practice of endoscopic mucosal resection in Japan. These minimally invasive techniques allow safe and effective treatment of diseases that would otherwise require major surgery. This article provides an overview of endoscopic mucosal resection techniques, their associated outcomes, and other potential applications of endoscopic mucosal resection.
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Endoscopía Gastrointestinal/métodos , Neoplasias Gastrointestinales/cirugía , Neoplasias del Colon/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo , Neoplasias Esofágicas/cirugía , Mucosa Gástrica/cirugía , Humanos , Mucosa Intestinal/cirugía , Japón , Procedimientos Quirúrgicos Mínimamente Invasivos , Seguridad , Neoplasias Gástricas/cirugía , Resultado del TratamientoRESUMEN
Eosinophilic esophagitis is a morphologic finding that may result from a wide spectrum of clinical conditions. The distinctive histological features accompanying eosinophilic esophagitis may facilitate the diagnosis of the underlying disease entity. Unfortunately, there are no pathognomonic histologic characteristics associated with eosinophilic esophagitis. Clinical signs and symptoms, immunological markers, endoscopic findings, and response to therapy may help establish or confirm the diagnosis of a clinical condition that results in eosinophilic esophagitis. The following discussion outlines the causes of eosinophilia in an esophageal biopsy sample.
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Eosinofilia/patología , Neoplasias Esofágicas/patología , Esofagitis/patología , Leiomiomatosis/patología , Biopsia con Aguja , Diagnóstico Diferencial , Eosinofilia/diagnóstico , Neoplasias Esofágicas/diagnóstico , Esofagitis/diagnóstico , Esofagitis Péptica/diagnóstico , Esofagitis Péptica/patología , Esofagoscopía , Femenino , Humanos , Leiomiomatosis/diagnóstico , MasculinoAsunto(s)
Angiodisplasia/terapia , Esofagoscopía/métodos , Hemorragia Gastrointestinal/terapia , Angiodisplasia/complicaciones , Angiodisplasia/diagnóstico , Várices Esofágicas y Gástricas/patología , Várices Esofágicas y Gástricas/terapia , Estudios de Seguimiento , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Humanos , Ligadura/métodos , Masculino , Persona de Mediana Edad , Resultado del TratamientoAsunto(s)
Malformaciones Arteriovenosas/terapia , Enfermedades Duodenales/terapia , Endoscopía Gastrointestinal/métodos , Hemorragia Gastrointestinal/terapia , Úlcera Gástrica/terapia , Adulto , Anciano , Arterias/anomalías , Malformaciones Arteriovenosas/complicaciones , Enfermedades Duodenales/complicaciones , Duodeno/irrigación sanguínea , Femenino , Hemorragia Gastrointestinal/etiología , Humanos , Ligadura/métodos , Masculino , Estómago/irrigación sanguínea , Úlcera Gástrica/complicaciones , Resultado del TratamientoRESUMEN
The treatment of patients who have malignant gastric-outlet, duodenal and small intestinal obstructions is difficult. The morbidity and mortality of palliative surgery in these patients is significant. It is not uncommon for patients to be treated with supportive therapy only, which unfortunately, neither relieves the severe nausea and vomiting, nor allows adequate food intake. Over the past few years, a number of studies have reported the safety and efficacy of self-expanding metal stents used to palliate malignant upper gastrointestinal obstruction. In this article, the authors focus on the use of self-expanding metal stents to treat malignant gastric-outlet, duodenal, and small intestinal obstructions.
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Obstrucción Duodenal/cirugía , Obstrucción de la Salida Gástrica/cirugía , Obstrucción Intestinal/cirugía , Intestino Delgado/cirugía , Implantación de Prótesis/instrumentación , Stents , Materiales Biocompatibles , Neoplasias del Sistema Digestivo/complicaciones , Neoplasias del Sistema Digestivo/diagnóstico por imagen , Neoplasias del Sistema Digestivo/cirugía , Obstrucción Duodenal/diagnóstico por imagen , Obstrucción Duodenal/etiología , Obstrucción de la Salida Gástrica/diagnóstico por imagen , Obstrucción de la Salida Gástrica/etiología , Humanos , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/etiología , Metales , Radiografía Abdominal , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
BACKGROUND: The accuracy and complication rates of brush cytology obtained from pancreaticobiliary strictures have not been fully defined. In this study we compared the accuracy and complications of brush cytology obtained from bile versus pancreatic ducts. METHODS: We identified 148 consecutive patients for whom brush cytology was done during an ERCP from a database with prospectively collected data. We compared cytology results with the final diagnosis as determined by surgical pathologic examination or long-term clinical follow-up. We followed all patients and recorded ERCP-related complications. RESULTS: Forty-two pancreatic brush cytology samples and 101 biliary brush cytology samples were obtained. The accuracy rate of biliary cytology was 65 of 101 (64.3%) and the accuracy rate of pancreatic cytology was 30 of 42 (71.4%). Overall sensitivity was 50% for biliary cytology and 58.3% for pancreatic cytology. Of 67 patients with pancreatic adenocarcinoma, sensitivity for biliary cytology was 50% versus 66% for pancreatic cytology. Concurrent pancreatic and biliary cytology during the same procedure increased the sensitivity in only 1 of 10 (10%) patients. Pancreatitis occurred in 11 (11%) patients (9 mild cases, 2 moderate cases) after biliary cytology and in 9 (21%) patients (6 mild cases, 3 moderate cases) after pancreatic cytology (p = 0.22). In 10 patients who had pancreatic brush cytology, a pancreatic stent was placed. None of these patients developed pancreatitis versus 9 of 32 (28%) patients in whom a stent was not placed (p = 0.08). Pancreatic cytology samples obtained from the head of the pancreas were correct in 13 of 18 (72%) cases, from the genu in 7 of 7 (100%) cases, from the body in 5 of 9 (55%) cases, and from the tail in 4 of 7 (57%) cases. CONCLUSION: The accuracy of biliary brush cytology is similar to the accuracy of pancreatic brush cytology. The yield of the latter for pancreatic adenocarcinoma is similar to that of the former. Complication rates for pancreatic cytology are not significantly higher than the rates for biliary cytology. The placement of a pancreatic stent after pancreatic brushing appears to reduce the risk of postprocedure pancreatitis.
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Conductos Biliares/patología , Colestasis/patología , Citodiagnóstico/efectos adversos , Citodiagnóstico/métodos , Conductos Pancreáticos/patología , Pancreatitis/etiología , Adenocarcinoma/complicaciones , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Colangiopancreatografia Retrógrada Endoscópica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/patología , Sensibilidad y Especificidad , StentsRESUMEN
OBJECTIVE: Assessment of the feasibility of conducting clinical research with patients using electronic mail and the World Wide Web. DESIGN: We re-contacted 463 patients with ulcerative colitis (UC) and 154 benign prostatic hyperplasia (BPH) patients who had provided us with e-mail addresses as part of a Web-based study. In an electronic mail message, we informed patients of a web site with a new study and invited them to participate. We then examined the factors associated with patients' participation in the new study. RESULTS: Completion rates were 28% for UC patients (single mailing) and 48% for BPH patients (up to four mailings in a two-month period). Some patients could not be contacted due to invalid e-mail addresses (23%). Those who completed the new study tended to be older, and less time had elapsed since their participation in the previous study. Furthermore, their health-related quality-of-life had significantly improved since the previous study. CONCLUSION: It is possible to use direct electronic mail contact to conduct follow-up research with patients. Response rates appear to be related to the number of messages sent, age of the recipients, and time since the initial contact.
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Encuestas Epidemiológicas , Internet , Calidad de Vida , Colitis Ulcerosa , Estudios de Factibilidad , Humanos , Masculino , Hiperplasia Prostática , Proyectos de InvestigaciónRESUMEN
Simple epithelia express keratins 8 (K8) and 18 (K18) as their major intermediate filament (IF) proteins. One important physiologic function of K8/18 is to protect hepatocytes from drug-induced liver injury. Although the mechanism of this protection is unknown, marked K8/18 hyperphosphorylation occurs in association with a variety of cell stresses and during mitosis. This increase in keratin phosphorylation involves multiple sites including human K18 serine-(ser)52, which is a major K18 phosphorylation site. We studied the significance of keratin hyperphosphorylation and focused on K18 ser52 by generating transgenic mice that overexpress a human genomic K18 ser52--> ala mutant (S52A) and compared them with mice that overexpress, at similar levels, wild-type (WT) human K18. Abrogation of K18 ser52 phosphorylation did not affect filament organization after partial hepatectomy nor the ability of mouse livers to regenerate. However, exposure of S52A-expressing mice to the hepatotoxins, griseofulvin or microcystin, which are associated with K18 ser52 and other keratin phosphorylation changes, resulted in more dramatic hepatotoxicity as compared with WT K18-expressing mice. Our results demonstrate that K18 ser52 phosphorylation plays a physiologic role in protecting hepatocytes from stress-induced liver injury. Since hepatotoxins are associated with increased keratin phosphorylation at multiple sites, it is likely that unique sites aside from K18 ser52, and phosphorylation sites on other IF proteins, also participate in protection from cell stress.
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Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Filamentos Intermedios/fisiología , Queratinas/química , Células 3T3 , Citoesqueleto de Actina/ultraestructura , Sustitución de Aminoácidos , Animales , Predisposición Genética a la Enfermedad , Griseofulvina/toxicidad , Hepatectomía , Humanos , Filamentos Intermedios/ultraestructura , Queratinas/genética , Queratinas/metabolismo , Regeneración Hepática , Ratones , Ratones Transgénicos , Microcistinas , Ácido Ocadaico/farmacología , Péptidos Cíclicos/toxicidad , Fosforilación , Mutación Puntual , Procesamiento Proteico-PostraduccionalRESUMEN
The first description of endoscopic sphincterotomy 25 years ago spearheaded the widespread use of endoscopic treatment of choledocholithiasis. It is largely accepted that common bile duct stone removal should be endoscopic rather than surgical in patients who have undergone previous cholecystectomy, in the high-risk surgical patient when the gallbladder is still present, in patients with severe acute cholangitis, in selected patients with acute biliary pancreatitis, and in special circumstances for the average risk surgical patient with suspected choledocholithiasis before laparoscopic cholecystectomy. We have summarized a number of endoscopic techniques that are used in the management of bile duct stone disease.
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Cálculos Biliares/cirugía , Esfinterotomía Endoscópica , Cateterismo , Colangiopancreatografia Retrógrada Endoscópica , Cálculos Biliares/diagnóstico por imagen , Cálculos Biliares/terapia , Humanos , Litotricia/métodos , Esfinterotomía Endoscópica/efectos adversos , Esfinterotomía Endoscópica/métodosRESUMEN
OBJECTIVES: We sought to study the utility of liver function test abnormalities concomitant with biliary symptoms in predicting a favorable response to endoscopic sphincterotomy in patients with Geenen class II sphincter of Oddi dysfunction. METHODS: We reviewed the clinical course and liver function test results of 24 Geenen-Hogan class II postcholecystectomy patients with biliary colic secondary to sphincter of Oddi dysfunction who did not undergo sphincter of Oddi manometry before treatment with endoscopic sphincterotomy. RESULTS: Twenty of the 24 patients had an average of 1.4 episodes of abnormal liver function tests associated with biliary colic; eight patients had dilated common bile duct on cholangiogram. Eighteen of the 20 patients with abnormal liver function tests (90%) were pain-free after sphincterotomy; in contrast, only one of four patients (25%) without liver function test changes responded to sphincterotomy. Fisher exact analysis showed that abnormal liver function tests was a significant predictor for favorable response to sphincterotomy with a two-tail p value of 0.018. Of the eight patients with bile duct dilatation, six (75%) responded favorably to sphincterotomy, whereas 13 of 16 patients (81%) without dilatation also responded to sphincterotomy. Analysis of common bile duct dilatation as a predictive factor showed no significance (p=1.00). CONCLUSIONS: We conclude that the occurrence of abnormal liver function tests during biliary colic may be used to select patients for endoscopic sphincterotomy. Sphincter of Oddi manometry may not be needed in these cases.
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Enfermedades del Conducto Colédoco/fisiopatología , Pruebas de Función Hepática , Esfínter de la Ampolla Hepatopancreática/fisiopatología , Esfinterotomía Endoscópica , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Colecistectomía , Cólico/fisiopatología , Cólico/cirugía , Enfermedades del Conducto Colédoco/cirugía , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , Selección de Paciente , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/cirugía , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: Treatment options for malignant gastric outlet obstruction are limited. Surgical gastrojejunostomy, commonly performed, has significant morbidity and mortality. METHODS: Over 2 years, we prospectively studied the safety, feasibility, and outcomes for use of a newly designed expandable metal stent (Wallstent Enteral; Schneider, Minneapolis, Minn.) to treat malignant gastric outlet obstruction. Stents 16 to 22 mm in diameter and 60 to 90 mm in length were deployed directly through the endoscope. RESULTS: Twelve patients (ten women, two men; mean age 59.7 years) underwent stenting. Thereafter, six patients were able to eat a regular diet; three could eat pureed food. In three patients, the procedure was unsuccessful because of multiple obstructions not recognized before stenting (one) and stents deployed too proximally (one) or too distally (one). CONCLUSIONS: Placement of a newly designed stent through the endoscope is safe and effective palliation for various types of malignant gastric outlet obstruction and significantly improves many aspects of patient quality of life.
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Obstrucción Duodenal/etiología , Obstrucción Duodenal/terapia , Obstrucción de la Salida Gástrica/etiología , Obstrucción de la Salida Gástrica/terapia , Cuidados Paliativos/métodos , Stents , Endoscopía Gastrointestinal , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Estudios Prospectivos , Factores de Tiempo , Resultado del TratamientoRESUMEN
Urgent management of acute biliary pancreatitis has increasingly included early endoscopic intervention. Endoscopic intervention allows effective removal of the offending stone(s) and reestablishment of biliary drainage. Four randomized controlled trials involving more than 800 patients in Western and Asian countries have been completed. This article summarizes the findings of these studies and proposes a preferred approach to the management of acute biliary pancreatitis.
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Colelitiasis/cirugía , Endoscopía , Pancreatitis/cirugía , Enfermedad Aguda , Algoritmos , Enfermedades de los Conductos Biliares/diagnóstico , Enfermedades de los Conductos Biliares/cirugía , Colangiopancreatografia Retrógrada Endoscópica , Colelitiasis/diagnóstico , Diagnóstico por Imagen , Humanos , Pancreatitis/etiología , Pancreatitis/terapia , Ensayos Clínicos Controlados Aleatorios como Asunto , Esfinterotomía EndoscópicaRESUMEN
The role of endoscopic ultrasound (EUS) in the detection and staging of pancreatic cancer is well established in medical literature. The development of EUS-guided fine needle aspiration (FNA) and subsequently EUS-guided fine needle injection (FNI) has expanded the clinical utility of EUS. These newer techniques made "interventional" EUS possible. Several recent applications of EUS-guided FNI include celiac nerve block, pseudocyst drainage, and drug delivery into pancreatic tumors. EUS is also gaining acceptance as an alternative diagnostic modality in the management of choledocholithiasis. The value of EUS in the diagnosis of early chronic pancreatitis is still being actively studied. This article reviews a number of recent developments in EUS-guided diagnosis and therapy with an emphasis on EUS-guided FNA and EUS-guided FNI.
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Endosonografía , Enfermedades Pancreáticas/diagnóstico , Enfermedades Pancreáticas/terapia , Drenaje , Humanos , Bloqueo Nervioso , Enfermedades Pancreáticas/diagnóstico por imagen , Seudoquiste Pancreático/diagnóstico , Seudoquiste Pancreático/cirugía , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: The World Wide Web (WWW) is a new communications medium that permits investigators to contact patients in nonmedical settings and study the effects of disease on quality of life through self-administered questionnaires. However, little is known about the feasibility and, what is more important, the validity of this approach. An on-line survey for patients with ulcerative colitis (UC) and patients whose UC had been treated with surgical procedures was developed. To understand how patients on the WWW might differ from those in practice and the potential biases in conducting epidemiological research in volunteers recruited on the Internet, post-surgery patients who responded to the WWW survey were compared with those in a surgical practice. SETTING: The Internet and private practice surgical clinic. MAIN OUTCOMES: Scores from the Short form 36 (SF-36) Health Assessment Questionnaire and the Self-Administered Inflammatory Bowel Disease Questionnaire (IBDQ). RESULTS: Over a 5-month period, 53 post-surgery patients enrolled in the Internet study; 47 patients from a surgical clinic completed the same computer-based questionnaire. Surgically treated patients on the WWW were younger than their clinic counterparts (median age category 35-44 years vs. 45-54 years, p = 0.01) but more ill with a lower summary IBDQ score (168 vs. 186, p = 0.019) and lower health status across almost all dimensions of the SF-36 (p = 0.016). CONCLUSIONS: It is feasible to conduct epidemiological research on the effects of UC on quality of life on the Web; however, systematic differences in disease activity between volunteer patients on the WWW and "in the clinic" may limit the applicability of results.