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Michael V Sivak

Publications and source records attributed to Michael V Sivak.

17 recordsLinked to original sources
PubMed2003

Prospective evaluation of 4-mm diameter endoscopes for esophagoscopy in sedated and unsedated patients.

BACKGROUND: Unsedated esophagoscopy with small-diameter endoscopes is generally well tolerated but of limited sensitivity for the diagnosis of esophageal mucosal disease. This study evaluated the sensitivity of esophagoscopy performed with new 4-mm diameter prototype battery-powered and video endoscopes. Patient tolerance for an unsedated examination with the 4-mm endoscopes was assessed and the performance characteristics of the battery-powered and video 4-mm endoscopes were compared. METHODS: Patients referred for EGD were recruited to undergo an additional examination with a 4-mm endoscope. A prototype 60-cm long, 4-mm diameter battery-powered fiberoptic esophagoscope was used in the first 24 patients and a prototype 60-cm long, 4-mm diameter video esophagoscope in the next 27 patients. Examiners who were unaware of patient history and procedure indications recorded esophageal findings, ease of intubation, optical quality (5-point visual scale), and time for examination of the esophagus and then recorded esophageal findings after the standard EGD. RESULTS: The sensitivity, specificity, and accuracy for identification of Barrett's esophagus was 100%; overall sensitivity, accuracy, and specificity for detecting esophageal lesions were, respectively, 91%, 98%, and 99%. Patient tolerance (assessed by symptom scores for choking, pain, and discomfort) and acceptability of unsedated esophagoscopy with the 4-mm diameter instruments were significantly better than in a historical group of patients examined with a 3-mm diameter endoscope. The optical quality of video endoscope was rated as superior to that of battery-powered endoscope, and esophageal examination was performed significantly quicker with the video versus the battery-powered endoscope (68 vs. 137 seconds; p = 0.001). CONCLUSIONS: Unsedated esophagoscopy with 4-mm diameter endoscopes may be an alternative to EGD for screening for Barrett's esophagus. Given the current state of endoscopic technology, a minimum diameter of 4 mm is required for satisfactory esophageal imaging.

Barrett Esophagus↗
PubMed2003

Clinical utility of intraductal US for evaluation of choledocholithiasis.

BACKGROUND: Intraductal US can improve the diagnostic accuracy of cholangiography performed under C-arm fluoroscopy in patients with suspected choledocholithiasis. This study aimed to determine the clinical utility of intraductal US for patient management. METHODS: Patients with suspected choledocholithiasis undergoing ERCP with a C-arm fluoroscope at two tertiary academic medical centers were enrolled. After initial cholangiography, findings and decisions concerning the need for further interventions were recorded. Intraductal US (20 MHz) was then selectively performed in patients with equivocal cholangiography or those without cholangiographic evidence of bile duct stones. Intraductal US was also performed after endoscopic sphincterotomy and stone extraction to confirm bile duct clearance. RESULTS: Fifty-two patients (28 men, 24 women) were enrolled and intraductal US was selectively performed in 35 (64%). Of the 21 patients with normal cholangiography, 8 (38%) had stones or sludge by intraductal US. Endoscopic sphincterotomy was performed as a direct result of intraductal US in these 8 and the findings were confirmed in 7. In the 14 patients in whom cholangiography demonstrated small (<5 mm) or round filling defects, intraductal US concurred in 9 and found air bubble/no stone in 5. Sphincterotomy was avoided in these 5 patients. Overall, intraductal US led to a change in clinical management in 13 of 35 patients (37%) in whom it was performed. CONCLUSIONS: Selective use of intraductal US affects the clinical management of a large proportion of patients who undergo C-arm fluoroscopy-guided ERCP for suspected bile duct stones.

Adult↗
PubMed2003

Criteria for the diagnosis of dysplasia by endoscopic optical coherence tomography.

BACKGROUND: Endoscopic optical coherence tomography provides images of the GI mucosa and submucosa in microscopic detail. It is unknown whether endoscopic optical coherence tomography can reliably detect dysplasia. Colon polyps were used as a model to determine whether dysplasia in GI tissue has characteristic optical coherence tomography imaging features. METHODS: Endoscopic optical coherence tomography images of colon polyps and normal colon tissue were obtained at colonoscopy. In real time, endoscopists compared tissue organization and light scattering for polyps and normal mucosa with endoscopic optical coherence tomography. Imaged polyps were removed and evaluated histopathologically. Organization and light scattering, as assessed by endoscopic optical coherence tomography at colonoscopy, were compared for adenomas versus hyperplastic polyps. A computer program also quantified and compared the degree of light scattering for hyperplastic polyps and adenomas. RESULTS: A total of 44 polyps were imaged in 24 patients (30 adenomas, 14 hyperplastic polyps). Endoscopic optical coherence tomography images of adenomas had significantly less structure (p = 0.0005) and scattered light to a lesser degree than hyperplastic polyps (p = 0.0007). Hyperplastic polyps were significantly closer in organization (p = 0.0003) and light scattering (p = 0.0006) to normal mucosa as compared with adenomas. By digital image analysis, the light-scattering property of hyperplastic polyps was closer to normal mucosa compared with adenomas (14.86 vs. 45.81; p = 0.0001). CONCLUSIONS: Real-time endoscopic optical coherence tomography imaging differentiated adenomas, hyperplastic polyps, and normal colon tissue. By using the colon adenoma as a model, the endoscopic optical coherence tomography characteristics of dysplasia are loss of tissue organization and reduced light scattering.

Adenoma↗
PubMed2003

Effectiveness of open-access endoscopy in routine primary-care practice.

BACKGROUND: Direct referral of patients for endoscopic procedures without prior consultation (open-access endoscopy) has become commonplace. However, the effect of open-access endoscopy on the care of patients in routine clinical practice has not been studied. METHODS: The impact of open-access endoscopy was examined in 168 consecutive patients referred from 8 primary-care practices to our tertiary hospital-based endoscopy center. The effectiveness of open-access endoscopy was assessed by review of office medical records at the primary-care practice sites for a minimum follow-up period of 6 months. Outcome measures evaluated included postprocedure communication between primary-care physician and patient, primary-care physician adherence to postprocedure recommendations, and the need for subsequent diagnostic evaluation and/or consultation. RESULTS: The mean age of the 168 patients was 60 years; 56 (33%) underwent EGD and 112 (67%) had colonoscopy; 65% were from hospital-based practices and 35% from community practices. The indication(s) for 77% of the procedures met American Society for Gastrointestinal Endoscopy guidelines for the appropriate use of endoscopy. An office follow-up was noted for 82% of patients after the open-access procedure. Discussion of results was documented in 61% of the patient charts. Compliance with diagnostic and therapeutic recommendations was documented, respectively, in 75% and 90% of patient charts. A follow-up GI consultation was requested for only 7% of the patients. CONCLUSION: Open-access endoscopy in the primary-care setting is effective to the extent that subsequent GI consultations are rare and the level of compliance with endoscopist recommendations is high. However, documentation of communication of the results of endoscopy with the patient can be improved.

Aged↗
PubMed2002

Visualization of subsurface blood vessels by color Doppler optical coherence tomography in rats: before and after hemostatic therapy.

BACKGROUND: The ability to visualize subsurface blood vessels and measure flow may be useful in certain experimental and clinical settings. METHODS: Color Doppler optical coherence tomography was used to visualize and measure blood flow in subsurface vessels in vivo in a rat skin flap model. Local "hemostatic" interventions (epinephrine or sclerosant injection, heat probe, and laser) were then applied and imaging was repeated. The skin flap was evaluated histologically. RESULTS: Subsurface blood vessels were easily visualized in cross-section, and vessel diameter and bidirectional blood flow velocity were readily measured. Color Doppler optical coherence tomography demonstrated that flow was significantly reduced after epinephrine injection and became undetectable after the other interventions. This correlated with pathologic evidence of vessel damage in all interventions, except for epinephrine injection. Although vessel response was as predicted to most interventions, the response to epinephrine was only temporary, and limited application of heat alone from the heat probe halted flow without visually apparent surface injury. CONCLUSIONS: Color Doppler optical coherence tomography provides high-resolution, cross-sectional flow imaging in subsurface blood vessels. Color Doppler optical coherence tomography is potentially a better technique for the study of existing and new hemostatic intervention in the laboratory. Potential future clinical applications include monitoring of the response to hemostatic modalities.

Animals↗
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

Evidence-based endoscopy.

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Cholangiopancreatography, Endoscopic Retrograde↗
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↗