Biomedical subjects

Amitabh Chak

Publications and source records attributed to Amitabh Chak.

64 records · Page 4Linked to original sources

PubMed2002

Accuracy of a narrow-diameter battery-powered endoscope in sedated and unsedated patients.

BACKGROUND: Esophagoscopy with a portable battery-powered endoscope could provide a safe, inexpensive, and minimally invasive way to screen for Barrett's esophagus or esophageal varices. The use of such an instrument in an unsedated fashion has not been previously evaluated. METHODS: Patients referred for an EGD were recruited to undergo an additional examination with the battery-powered endoscope before EGD. In phase 1, (n = 42) patients received conscious sedation before the battery-powered endoscopic examination. In phase 2, (n = 56) patients were not sedated and were given the option of a peroral (n = 43) or transnasal (n = 13) endoscopy. Examiners were blinded to patient history and procedure indications. Esophageal findings, ease of intubation, optical quality, and patient comfort for the battery-powered endoscope and standard EGD were recorded by the endoscopist. RESULTS: Ninety-eight patients (60 men, 38 women, mean age 53 years) were recruited. The sensitivity for detecting Barrett's esophagus, esophageal tumors, and esophageal varices was 54.5%, 66.7%, and 80%, respectively. Ease of intubation and patient comfort as perceived by the endoscopist were not significantly different between the battery-powered endoscope and EGD. Optical quality was ranked as less than 4 (on a 5-point scale with 5 = standard EGD and 1 = poor) in 42% of battery-powered endoscopic examinations. There were no complications. CONCLUSION: The accuracy of esophageal examination with a 3.1-mm endoscope is substantially inferior to standard EGD. Thus, the battery-powered endoscope would not be useful for screening patients for Barrett's esophagus or varices unless improvements in optical quality and visualization are made.

Adult↗

PubMed2002

A prospective evaluation of outcome in patients referred for PEG placement.

BACKGROUND: PEG feeding is not recommended for short-term use because the 30-day mortality after PEG placement is substantial. The primary aim of this study was to prospectively identify factors predictive of survival in patients referred for PEG placement. METHODS: All patients for whom gastroenterology consultation was sought for feeding PEG placement were prospectively studied. Demographic data, Charlson comorbidity index, and functional status were recorded at entry. After PEG placement, patients were followed for up to 12 months. RESULTS: Of the 67 patients for whom consultation was requested, 58 were eligible for the study and 50 underwent PEG placement. The 7-day and 30-day mortality rates in the PEG placement group were 4% and 20%, respectively. In multivariate analysis, only the Charlson index > or =4 was associated with decreased survival time (relative hazard = 2.9: 95% CI [1.20, 7.21], p = 0.019). Median survival in patients with Charlson comorbidity index > or =4 was significantly shorter than that in patients with Charlson index < 4 (p = 0.013). CONCLUSIONS: A Charlson comorbidity index > or =4 was significantly associated with shorter patient survival after initial consultation. Careful consideration of predictive factors of survival may improve patient selection for feeding PEG placement.

Aged↗

PubMed2002

EUS-guided fine needle aspiration of idiopathic abdominal masses.

BACKGROUND: EUS-guided fine needle aspiration (EUS-FNA) has significantly increased the diagnostic capability of EUS. FNA can also be helpful in the diagnosis of non-GI disorders. The role of EUS-FNA in the diagnosis of idiopathic abdominal masses has not been determined. This study evaluated the diagnostic accuracy of EUS-FNA of abdominal masses of unknown cause and its impact on subsequent evaluation and therapy. METHODS: Thirty-four patients from 5 tertiary referral centers (21 women, 13 men; mean age 54 years, range 27-72 years) with idiopathic abdominal masses underwent EUS-FNA. Presenting symptoms included the following: pain (29 patients), weight loss (15), altered bowel habits (7), nausea/vomiting (6), abnormal liver function tests (4), palpable mass (4), and urinary retention (1). Four patients had a history of intra-abdominal cancer (2 cervical, 1 ovarian, 1 colon). A final diagnosis by EUS-FNA, surgery, autopsy, or long-term follow-up was available in all patients. Abdominal masses were classified into 3 disease categories: infectious, benign/inflammatory, and malignant. RESULTS: Final diagnosis included infectious (5), benign/inflammatory (6), and malignant (23) abdominal mass. Overall, EUS-FNA established a tissue diagnosis in 29 of 34 patients (85%) in all 3 categories (infectious, 80%; benign/inflammatory, 67%; malignant, 91%). EUS-FNA was instrumental in directing subsequent evaluation in 29 patients (85%) and therapy in 26 (77%). The number of fine needle passes for adequate tissue sampling was lower for nonmalignant (2.2-3.2) versus malignant diseases (4.6). One complication occurred (perirectal abscess) and was treated successfully with antibiotics. CONCLUSIONS: EUS-FNA of idiopathic abdominal masses is safe and accurate and helps to guide subsequent evaluation and therapy in the majority of patients. The most common and promising area seems to be EUS-FNA of malignant abdominal masses. Transluminal EUS-FNA provides minimally invasive tissue sampling and obviates the need for exploratory laparotomy.

Abdomen↗

PubMed2002

Correlation of EUS measurement with pathologic assessment of neoadjuvant therapy response in esophageal carcinoma.

BACKGROUND: EUS-measured reduction in tumor size after neoadjuvant therapy has previously been correlated with downstaging and improved survival in patients with esophageal cancer. The aim of this study was to determine whether tumor changes measured by EUS correspond to pathologically assessed chemoradiotherapy-induced tumor regression. METHODS: Forty-one patients with esophageal cancer treated with combined modality treatment were studied. After initial EUS, patients completed a cisplatin/carboplatinum, 5-fluorouracil, and radiotherapy regimen and underwent repeat EUS before resection. A positive response on EUS was defined as a 50% reduction in maximal tumor cross-sectional area. Chemoradiotherapy-induced tumor regression was assessed in resection specimens by using a previously defined pathologic scoring system based on the extent of tumor proliferation into adjacent fibrosis. RESULTS: Pathologic tumor regression was present in 23, indeterminate in 5, and minimal or absent in 13 patients. EUS measured a positive response in 20 of 23 (87%) patients with CRT-induced tumor regression and a negative response in 10 of 13 (77%) patients with absent tumor regression (p < 0.001). EUS had a positive predictive value of 80% for pathologic tumor regression. CONCLUSIONS: Measurement of tumor size by EUS is a reliable clinical method for assessing pathologic tumor regression before surgery.

Adult↗

PubMed2002

Patient tolerance and acceptance of unsedated ultrathin esophagoscopy.

BACKGROUND: Unsedated endoscopy has not gained wide acceptance in the United States. Factors that may predict tolerance and acceptance of unsedated endoscopy are ill defined. METHODS: Outpatients referred for standard EGD were recruited to undergo unsedated ultrathin esophagoscopy (UUE) with a new 3.1-mm battery-powered esophagoscope before sedated EGD. They rated preprocedure and postprocedure anxiety levels with the Profile of Mood States Tension/Anxiety subscale (POMS-SF T/A). They also rated symptoms and overall acceptability and listed procedural preference between EGD and UUE. Patients who refused UUE noted a reason for refusal and also completed the anxiety questionnaire. RESULTS: Fifty-two of 98 patients recruited agreed to participate, and underwent both UUE and EGD. Patients who refused UUE were significantly more anxious (mean anxiety score, 8.2 vs. 4.5, p < 0.005). Participants reported no significant difference between preprocedural (4.6 vs. 5.3) or postprocedural (3.5 vs. 2.6) anxiety for UUE versus standard EGD. After undergoing both procedures, only 46% stated they would prefer UUE to EGD in the future. Patients who chose the peroral approach were more likely to prefer UUE than those who chose the transnasal approach (58% vs. 23%, p = 0.02). CONCLUSIONS: Patient acceptance of unsedated endoscopy even with an ultrathin instrument is limited. Anxiety assessment by the POMS-SF T/A can identify patients willing to undergo UUE. Patients who choose transoral UUE may be more willing to repeat the procedure.

Adult↗

PubMed2002

EUS-guided fine needle aspiration of the liver: indications, yield, and safety based on an international survey of 167 cases.

BACKGROUND: The liver is a common site of metastases for various malignancies. EUS-guided fine needle aspiration (EUS-FNA) of liver masses has only been reported in small series from single centers. METHODS: A retrospective questionnaire was sent by e-mail to 130 EUS-FNA centers around the world regarding indications, complications, and findings of EUS-FNA of the liver. RESULTS: Twenty-one centers reported 167 cases of EUS-FNA of the liver. A complication was reported in 6 (4%) of 167 cases including the following: death in 1 patient with an occluding biliary stent and biliary sepsis, bleeding (1), fever (2), and pain (2). EUS-FNA diagnosed malignancy in 23 of 26 (89%) cases after nondiagnostic fine needle aspiration under transabdominal US guidance. EUS localized an unrecognized primary tumor in 17 of 33 (52%) cases in which CT had demonstrated only liver metastases. EUS image characteristics were not predictive of malignant versus benign lesions. CONCLUSION: EUS-guided FNA of the liver appears to be a safe procedure with a major complication rate of approximately 1%. EUS-FNA should be considered when a liver lesion is poorly accessible to US-, or CT-guided FNA should be considered when US- or CT-guided FNA fail to make a diagnosis, when a liver lesion(s) is detected (de novo) by EUS, and for investigation of possible upper GI primary tumors in the setting of liver metastases.

Attitude of Health Personnel↗

PubMed2002

Endoscopic retrograde cholangiopancreatography in children and adolescents.

OBJECTIVES: Endoscopic retrograde cholangiopancreatography (ERCP) is becoming a more frequently used diagnostic and therapeutic tool in children. We sought to determine the indications, feasibility, safety, and effect on patient management of ERCP in pediatric patients of varying age. METHODS: All ERCPs performed during a 4-year period in patients aged 18 years or less at an academic hospital were retrospectively reviewed. The indications, type of anesthesia administered, type of duodenoscope used, diagnostic findings, therapeutic interventions, complication rate, and effect on management were compared between children (age 0-12 years) and adolescents (age 13-18 years). RESULTS: A total of 53 procedures were performed in 43 patients whose median age was 13.5 years. ERCP was successful in 50 of 53 cases (94%) with a complication rate of 6%. Endoscopic therapy was provided in 24 of 53 cases (45%). Compared with adolescents (n = 28), children (n = 25) were more likely to receive general anesthesia (96% vs. 29%; P < 0.001) and undergo ERCP with a pediatric duodenoscope (0% vs. 40%). ERCP affected management in 73% of cases, equally in both groups. CONCLUSION: ERCP is a successful and safe diagnostic and therapeutic modality in a variety of pancreatobiliary disorders that directly affects management in children of all ages.

Adolescent↗

PubMed2002

Endoscopic ultrasound-guided fine needle aspiration in the diagnosis of mediastinal masses of unknown origin.

OBJECTIVES: The ability of endosonography to diagnose a variety of gastrointestinal pathology has been significantly advanced with the introduction of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) biopsy. EUS-FNA technology can also be applied to the evaluation of non-GI disorders. The role of EUS-FNA to establish the diagnosis of unexplained mediastinal masses has not been previously described. The aim of this study was to determine the diagnostic accuracy, impact on subsequent workup, and role of EUS-FNA in treating mediastinal masses of unknown cause. METHODS: A total of 26 patients (15 men and 11 women, mean age 61 yr, range 39-77 yr) underwent EUS-FNA in patients presenting with unexplained mediastinal masses at four tertiary referral centers. Presenting symptoms included: chest pain (10 patients), dysphagia (eight), cough (seven), fever (six), night sweats (three), and no symptoms/abnormal x-ray (five patients). Five of 26 patients had prior history of cancer (three lung, one tracheal, and one esophageal). RESULTS: Final diagnosis using EUS-FNA, surgery, autopsy, other diagnostic study, or long-term follow-up was available in all patients. EUS-FNA results were classified under three disease categories: 1) infectious, 2) benign/ inflammatory, and 3) malignant. Final diagnosis included infectious in five patents, benign/inflammatory in nine, and malignant in 12. EUS-FNA was successful in 21 of 26 patients (81%) for all disease categories (infectious 60%, benign/inflammatory 78%, and malignant 92%). EUS-FNA was successful in directing subsequent workup in 77% (20 of 26) and therapy in 73% (19 of 26). Mean EUS-FNA passes for adequate tissue sampling was lower of nonmalignant disease categories (3.0 and 3.4) versus malignant disease (4.4). No complications were seen during the course of this study. CONCLUSIONS: EUS-FNA in patients presenting with idiopathic mediastinal masses establishes the diagnosis in the vast majority of cases, particularly for those with malignant disease. The emergence of transesophageal EUS-FNA of the mediastinum provides the ability to alter subsequent workup and therapy, obviating the need for more invasive diagnostic studies such as thoracotomy.

Adult↗

PubMedDate not supplied

Association of esophageal adenocarcinoma with other subsequent primary cancers.

PURPOSE: Esophageal adenocarcinoma shares risk factors such as obesity and smoking with other common cancers. The association of esophageal adenocarcinoma with other primary cancers has not been systematically evaluated. The authors used the Surveillance, Epidemiology and End-Results database of the National Cancer Institute to explore the association of esophageal adenocarcinoma with other primary cancers. PATIENTS AND METHODS: All adult patients with esophageal cancers, both adenocarcinoma and squamous cell carcinoma diagnosed between 1973 and 2001, were identified from the Surveillance, Epidemiology, and End-Results database, and standardized incidence rates were calculated for all subsequent primary cancers in these patients. The analysis was reversed to estimate the standardized incidence rate for subsequent primary esophageal cancer after a first primary cancer. RESULTS: In comparison with a standard population, patients with esophageal adenocarcinoma were at higher risk for the development of another subsequent cancer, specifically, cancers of the oral cavity and pharynx, lung and bronchus, and kidney and renal pelvis, and adenocarcinoma of the colon/rectum and pancreas. With squamous cell esophageal cancer, there was an association with tobacco-related cancers such as those of the oral cavity and pharynx, the lung and bronchus, and the breast. There was either no association or even a negative association of esophageal adenocarcinoma with other obesity-related cancers such as breast, uterine, and prostate cancers. CONCLUSIONS: Patients with esophageal adenocarcinoma and squamous cell carcinoma are at increased risk for the development of specific second primary cancers that share smoking as a common risk factor. Esophageal adenocarcinoma does not have a strong association with obesity-related cancers with respect to the relative risk for the development of subsequent primary cancers.

Adenocarcinoma↗

PubMedDate not supplied

A novel use of endoscopic clips in the treatment planning for radiation therapy (XRT) of esophageal cancer.

GOAL: To determine if the placement of metal endoclips improves radiotherapy (XRT) planning for esophageal cancer. BACKGROUND: XRT is an important modality in the treatment and palliation of esophageal cancer. Accurate simulation of the radiation field ensures optimal therapy while limiting toxicity. STUDY: Patients with esophageal carcinoma underwent EGD and endoscopic mucosal clip placement at the proximal and distal margins of the tumor. At XRT simulation the radiation oncologist simulated the field based on barium study, CT scan, and endoscopy report. A second radiation oncologist then assessed the ease of identification of the clips/margins of the tumor, shift in the field isocenter, and change in the radiation field width and length because of the metal clips. RESULTS: Seven patients with cancer of the esophagus had endoscopic clips placed followed by XRT simulation. The clips could be identified in all 7 patients. Simulation with the use of clips caused a shift in the field isocenter with a mean longitudinal shift (y-axis) of 3.5 cm (range, 1-6 cm) and a mean lateral shift (x-axis) of 0.33 cm (range, 0-1 cm). CONCLUSIONS: Endoscopically placed mucosal metal clips can aid field simulation when planning radiation therapy in patients with esophageal cancer.

Aged↗