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R H Hawes

Publications and source records attributed to R H Hawes.

At least 37 records · Page 2Linked to original sources
PubMed2001

Randomized controlled trial of EUS-guided fine needle aspiration techniques for the detection of malignant lymphadenopathy.

BACKGROUND: EUS-guided fine needle aspiration (EUS-FNA) is a highly accurate method of detecting malignant lymphadenopathy. The optimal methods for performing EUS-FNA to maximize sensitivity and to minimize the number of needle passes necessary are unknown. This is a report of the results of a prospective randomized controlled trial to determine the effect of suction, the site of FNA (edge or center of lymph node), and the method of preparation of cytologic specimens on accuracy, number of needle passes needed, and specimen quality. METHODS: Consecutive patients with lymphadenopathy detected by EUS underwent FNA. Each lymph node was sampled with or without suction and from the edge or center in a 2 x 2 factorial design. The samples were expressed onto slides for cytology, and the residual material in the needle was analyzed by the cytospin-cellblock technique. Each aspirate was individually characterized for a diagnosis of malignancy, cellularity, and bloodiness. RESULTS: Forty-three patients with a total of 46 lymph nodes were evaluated. The final lymph node diagnosis was benign in 22 (48%), "suspicious for malignancy" in 6 (13%), and malignant in 18 (39%). The use of suction was associated with an increase in the cellularity of the specimen, but did not improve the likelihood of obtaining a correct diagnosis (OR 1.52: 95% CI [0.81, 2.85]). Samples obtained with suction were of worse quality because of excessive bloodiness (OR 4.7: 95% CI [1.99, 11.24]). Aspiration from the edge of the lymph node (compared with the center) did not increase the likelihood of a correct diagnosis (OR 1.16: 95% CI [0.42, 3.21]). For 78% of malignant lymph nodes, the correct diagnosis was obtained on the first needle pass and for 100% by the third pass. Cytospin-cellblock methods did not add any additional diagnostic information compared with direct smear cytology. CONCLUSIONS: The traditional method of applying suction during EUS-FNA does not improve diagnostic accuracy and worsens specimen bloodiness compared with FNA without suction. The site of FNA within the lymph node does not affect accuracy. When EUS-FNA is necessary, our recommendation is up to 3 FNAs without suction from the most convenient and safe location within abnormal-appearing lymph nodes.

Biopsy, Needle↗
PubMed2001

The utility of EUS and EUS-guided fine needle aspiration in detecting celiac lymph node metastasis in patients with esophageal cancer: a single-center experience.

BACKGROUND: The aims of this study were to determine the utility of EUS and EUS-guided fine needle aspiration (EUS-FNA) in the detection and confirmation of celiac lymph node metastasis in patients with esophageal cancer and to define EUS features predictive of celiac lymph node metastasis in these patients. METHODS: The records of 211 patients with esophageal cancer who underwent EUS staging were reviewed. The operating characteristics of EUS were determined in patients where either surgery, EUS-FNA of a celiac lymph node, or both were performed (n = 102). The association between selected variables and the presence of celiac lymph node metastasis was evaluated by univariate and multivariable analyses. RESULTS: EUS in 48 patients provided a true-positive diagnosis of celiac lymph node involvement, a false-positive and false-negative result, respectively, in 6 and 14 patients, and a true-negative diagnosis in 34 patients. The sensitivity of EUS in detecting celiac lymph node was 77% (95% CI [67, 88]), specificity 85% (95% CI [74, 96]), negative predictive value 71% (95% CI [58, 84]), and the positive predictive value 89% (95% CI [81, 97]). EUS-FNA was performed in 94% (51/54) of patients with celiac lymph nodes. The accuracy of EUS-FNA in detecting malignant celiac lymph nodes was 98% (95% CI [90, 100]). Advanced T-stage, the need for dilation, detection of peritumoral lymph nodes, and black race were associated with celiac lymph node involvement. In multivariable analysis, advanced T-stage was the strongest predictor of celiac lymph node involvement. CONCLUSION: EUS and EUS-FNA are highly accurate in detecting and confirming celiac lymph nodes metastasis. Depth of tumor invasion as assessed by EUS is a strong predictor of celiac lymph node metastasis in patients with esophageal cancer.

Adenocarcinoma↗
PubMed2001

Increased transforming growth factor beta in pure pancreatic juice in pancreatitis.

Cytokines play an important role in the regulation of inflammation and fibrosis in the development of chronic pancreatitis. In this study, transforming growth factor beta (TGFbeta), interleukin (IL)-6, IL-10, and tumor necrosis factor alpha (TNFalpha) were measured in pure pancreatic juice obtained through pancreatic duct cannulation. Twenty patients with chronic pancreatitis were compared with six patients thought to be free of pancreatic disease who were undergoing endoscopic retrograde cholangiopancreatography for biliary tract disorders. TGFbeta was detected in 17 of 20 patients with chronic pancreatitis tested (85%), compared with only one patient in the control group (17%). There was no measurable amount of IL-10, IL-6, or TNFalpha in any of the pure pancreatic juice samples from any of the patients. These data indicate that TGFbeta may play an active role in the advancement of pancreatitis by causing local inflammation and inducing fibroblasts to secrete collagen. This finding may be relevant in the future for identifying patients whose conditions may advance to chronic pancreatitis, and blocking the effects of TGFbeta could have therapeutic effects.

Adolescent↗
PubMed2001

Endoscopic ultrasound in the evaluation and treatment of chronic pancreatitis.

Endoscopic ultrasound (EUS) was developed in the 1970s specifically for the purpose of improved imaging of the pancreas. The close proximity of the pancreas to the gastric and duodenal lumen allows EUS to obtain high-resolution images, unobstructed by overlying bowel gas. EUS has fewer complications than endoscopic retrograde cholangiopancreatography (ERCP) and can detect features of chronic pancreatitis (CP) in the pancreatic parenchyma and duct that are not visible to any other imaging modality. Because of this high sensitivity, questions have arisen whether EUS is oversensitive, especially to ''early" CP. Without a definitive gold standard against which to measure EUS (or ERCP and function testing), it is currently not possible to know the true accuracy of these modalities for early CP. There is now an extensive body of literature suggesting that these early changes detected by EUS correlate with histologic changes of CP, and may predict response to pancreatic therapy. EUS is uniquely suited to performing endoscopic cyst drainage for pancreatic pseudocysts and for controlling the pain of CP by EUS-directed celiac plexus block. For endoscopic cystenterostomy, EUS allows the endoscopist to localize the cyst, determine if the cyst is drainable, and guide a needle and stent into the cyst in a single step. Several major questions remain. Can EUS features of CP guide other forms of therapy for CP such as enzyme replacement, sphincter of Oddi therapy, and stent therapy? Can the detection of early CP by EUS, and subsequent therapy, delay or prevent the onset of more severe CP? Can EUS detect early forms for dysplasia and malignancy in patients who are at high risk for pancreatic carcinoma? Do changes of "early" CP detected by EUS progress to more classic changes (calicification) over time?

Adult↗
PubMed2001

EUS to the rescue?

Explore the source record for details and available documents.

Biopsy, Needle↗
PubMed2001

The decision-making value of magnetic resonance cholangiopancreatography in patients seen in a referral center for suspected biliary and pancreatic disease.

OBJECTIVE: To assess the ability of MRCP to alter the differential diagnosis and to prevent diagnostic and/or therapeutic ERCP. The diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) for biliary and pancreatic disease is well documented. Some believe MRCP may prevent diagnostic ERCP or add useful information, however there are no reports of its impact on clinical management. METHODS: Consecutive patients referred for ERCP underwent clinic evaluation, then MRCP, and then ERCP. In Phase 1, the number of differential diagnoses and the perceived need for diagnostic ERCP were evaluated after each step by the endoscopist who performed the ERCP. In Phase 2, the process was repeated after presenting clinical information and MRCP results to different individual physicians: another endoscopist, a hepatologist, a radiologist, and a surgeon (all were blinded to ERCP results). RESULTS: Forty patients were enrolled. Clinical contexts were jaundice (19.7%), abnormal liver enzymes (42.6%), abdominal pain (11.5%), recurrent acute pancreatitis (11.5%), and suspected complications of chronic pancreatitis (14.7%). In Phase 1, adding MRCP information to diagnostic ERCP information did not change the mean number of differential diagnoses significantly and prevented no therapeutic ERCP. In Phase 2, adding MRCP to clinical information only (without ERCP) reduced the differential diagnosis significantly for the radiologist and the surgeon only and would have prevented < or =3% of diagnostic and therapeutic ERCP for all physicians. CONCLUSION: The value of MRCP information may be limited if patient selection is inappropriate and may differ in physicians depending on their speciality.

Biliary Tract Diseases↗
PubMed2001

Cholecystokinin-Stimulated mebrofenin (99mTc-Choletec) hepatobiliary scintigraphy in asymptomatic postcholecystectomy individuals: assessment of specificity, interobserver reliability, and reproducibility.

OBJECTIVES: Cholecystokinin-stimulated hepatobiliary scintigraphy (CCK-HBS) is a noninvasive method reported to be highly accurate in the diagnosis of sphincter of Oddi dysfunction. Our primary aim was to assess the specificity of CCK-HBS by evaluating its ability to exclude disease in 20 asymptomatic postcholecystectomy individuals. Secondary aims were to assess the interobserver reliability in scoring the CCK-HBS examinations between three blinded observers and to assess reproducibility of CCK-HBS repeated in the same individuals. METHODS: Twenty asymptomatic postcholecystectomy individuals with normal liver serum chemistries underwent CCK-HBS on two separate occasions. Three nuclear medicine specialists read each CCK-HBS study in a blinded fashion. RESULTS: There was good agreement between the three observers reading the same scans for both the first scan (kappa = 0.554) and the second scan (kappa = 0.507). There was poor agreement between the first and second scans on the same patient, read by the same nuclear medicine specialist (kappa = 0.062-0.385). The overall specificity of the CCK-HBS score was 77.5%; however, the specificity was only 60% when a true negative was defined as two negative CCK-HBS examinations. CONCLUSIONS: Quantitative CCK-HBS is of poor specificity in asymptomatic postcholecystectomy individuals. Hence, it is of questionable value in excluding sphincter of Oddi dysfunction in patients suspected to suffer from this disorder.

Adult↗
PubMed2001

Perspectives in endoscopic mucosal resection.

The birth of endoscopic mucosal resection probably can be traced back to the early days of colonoscopy and polypectomy. With the advent of colonoscopy, endoscopists began encountering pedunculated and sessile mass lesions arising from the mucosal surface. The concept of snare polypectomy developed quickly, and this technique has become the standard of care in the management of colon polyps. Large sessile lesions, however, remain problematic, especially when they arise from the thin wall of the cecum and ascending colon. Serosal burns and frank perforations represent the most significant complication of this technique.

Digestive System Neoplasms↗
PubMed2000

Imaging of esophageal tumors with a water-filled condom and a catheter US probe.

BACKGROUND: High-frequency catheter ultrasound (C-EUS) probes provide high resolution images of the gastrointestinal tract. Their use in the esophagus is limited by the requirement for a water-filled lumen for good acoustical coupling. We have developed a system using a condom that provides a continuous column of water for high resolution C-EUS imaging of the esophagus. METHODS: Nine patients underwent condom C-EUS for evaluation of esophageal mucosal and submucosal tumors. A standard latex condom was attached to a 2-channel endoscope and filled with water after esophageal intubation. A 20 MHz C-EUS probe placed within the water-filled condom was used to characterize all lesions. RESULTS: The condom C-EUS system provided a 360 degree, high resolution image throughout the length of the esophagus without air artifact and without the risk of aspiration associated with filling the esophageal lumen with water. Complete imaging of the tumor was obtained in all cases, and no additional C-EUS procedures were required. The condom C-EUS was subjectively rated superior overall in comparison to standard C-EUS by 4 independent endosonographers. CONCLUSIONS: Condom C-EUS is a new method of high resolution imaging of the esophagus. This method provides a contained column of water within the esophagus that improves image quality and ease of use and may reduce the risk of aspiration.

Adenocarcinoma↗
PubMed2000

Dilation of malignant esophageal stenosis to allow EUS guided fine-needle aspiration: safety and effect on patient management.

BACKGROUND: Endoscopic ultrasonography (EUS) with fine-needle aspiration identifies patients with esophageal cancer who are unlikely to be cured by surgery. In approximately 30% of patients the staging procedure cannot be completed without dilation of an obstructing tumor. METHODS: All EUS examinations for esophageal cancer requiring dilation from July 1995 to December 1998 were included. Yield was defined as newly diagnosed metastatic (celiac lymph nodes) or locally invasive disease that could not have been detected without dilation. RESULTS: EUS was performed in 132 patients. Forty-two (32%) required 44 dilations. No complications occurred. Of the 42 patients with obstruction, 18 (43%) had celiac adenopathy of which 7 had malignant cells confirmed histologically, 3 had benign adenopathy, and 8 did not undergo fine-needle aspiration due to T4 stage disease (5) or intervening vessels (3). Two patients were upstaged after successful dilation from T2 N1 Mx to T4 N1 Mx and from T3 Nx Mx to T3 N1 M1. Overall, dilation allowed detection of advanced disease in 8 of 42 (19%) patients. Dilation to 11 to 12.8 mm was insufficient (36% success rate) to complete EUS compared with dilation to 14 to 16 mm (87%, p < 0.01). CONCLUSION: Dilation of obstructing esophageal tumors allows identification of a large number of patients with advanced stage malignancy. Dilation to 14 to 16 mm is sufficient for complete staging in almost all patients.

Aged↗
PubMed2000

Therapeutic ERCP in the management of pancreatitis in children.

BACKGROUND: The use of diagnostic and therapeutic endoscopic retrograde cholangiopancreatography (ERCP) is increasing in the management of pancreatobiliary diseases in children. METHODS: Over a 32-month period, we performed 34 ERCP procedures for the treatment of pancreatitis in 22 children at two university hospitals. Demographics and clinical data and ERCP findings were documented. Clinical status was assessed 6 months before the first ERCP and 6 months after the last ERCP, according to general condition, severity and frequency of pain, and health care encounters (emergency department visits, clinic visits, and hospital admissions related to the pancreatitis). RESULTS: Mean age of the patients was 10.7 years (range 1.5 to 17 years). Abdominal pain was the main presenting symptoms with hyperamylasemia and hyperlipasemia. Clinical diagnoses included acute pancreatitis (6), recurrent pancreatitis (5), and chronic pancreatitis (11). The mean follow-up was 16.4 months. Nine patients had sphincter manometry, with abnormal results leading to biliary sphincterotomy in 4. Fifteen patients underwent a total of 23 therapeutic ERCP procedures unrelated to sphincter dysfunction. There were 2 complications of 34 procedures (6%), both being mild pancreatitis after sphincter manometry. There were no deaths. There was a significant reduction in frequency (p < 0.01) and severity of pain (p < 0.01) after intervention. Patients without pancreatographic changes of chronic pancreatitis had the most marked clinical improvement (p < 0.05). In those with ductal changes of chronic pancreatitis, clinical improvement was not predicted by the extent of ductal changes. There was a significant decrease in health care encounters (p < 0.05) and improvement in general condition (p < 0.01) after endoscopic therapy, especially in those with a normal pancreatogram. CONCLUSIONS: Therapeutic ERCP is safe in pediatric patients with pancreatitis. Significant clinical improvement is achieved in patients with biliary or pancreatic stone disease. Prospective studies with long-term follow-up are needed to determine the impact of endoscopic therapy in patients with chronic pancreatitis and sphincter of Oddi dysfunction.

Acute Disease↗
PubMed2000

Virtual endoscopy--comparison with colonoscopy in the detection of space-occupying lesions of the colon.

BACKGROUND AND STUDY AIMS: A new technique has been described which combines abdominal helical computed tomography (CT) scanning and virtual reality computer technology, known as virtual colonoscopy (VC); the reconstructed images provide a simulation of the interior of the colon as viewed by endoscopy. We compared VC with conventional colonoscopy in patients with suspected or known colonic neoplasia. PATIENTS AND METHODS: A total of 38 patients, in whom there was a high likelihood of colonic polyps or cancer, underwent a noncontrast helical CT scan of the abdomen and pelvis after regular colonoscopy bowel preparation. The images were reconstructed into a VC presentation and compared with the subsequent conventional colonoscopy in a blinded manner. RESULTS: Conventional colonoscopy identified a total of 24 polyps 5 mm or greater. VC correctly identified five of 13 polyps 5-9 mm in size, and ten of 11 lesions greater than or equal to 10 mm in diameter. The reasons for four missed lesions were identified as being secondary to a collapsed rectum in two patients and stool in the right colon in two patients. The sensitivity and specificity per patient of VC for lesions greater than or equal to 5 mm were 66.7% and 75.0% respectively, and for lesions greater than 1 cm were 90.0% and 82.1%, respectively. CONCLUSIONS: Virtual colonoscopy is feasible, well tolerated, and capable of detecting most lesions greater than 10 mm in diameter. This technique is continuing to be developed and warrants further evaluation as a diagnostic and screening tool in colorectal neoplasia.

Adult↗
PubMed2000

EUS to detect evidence of pancreatic disease in patients with persistent or nonspecific dyspepsia.

BACKGROUND: Mild chronic pancreatitis is difficult to diagnose and the diagnosis is therefore not sought routinely in patients with dyspepsia. The aim of our study was to compare the prevalence of endosonographic pancreatic abnormalities in patients with dyspepsia and control subjects. METHODS: The number of endosonographic abnormalities was compared prospectively in patients with dyspepsia and control patients. Patients in whom there was any suspicion of pancreatic disease were analyzed separately. RESULTS: Between November 1998 and January 1999, 156 patients with dyspepsia were compared with 27 control patients. The groups were similar except that control patients were significantly older and more likely to be men. The mean number of endosonographic abnormalities was higher in dyspeptic patients than in control patients (mean number of abnormalities 3.3: 95% CI [2.9, 3.6] vs. 1.9: 95% CI [0.3, 1.7]). The strongest independent predictors of severe endosonographic abnormalities (defined as 5 or more abnormalities) were the presence of suspected pancreatic disease (odds ratio 7.29: 95% CI [2.03, 26. 14]) and dyspepsia (odds ratio 7.21: 95% CI [1.99, 26.26]). In the dyspepsia group, no clinical variables were significant predictors of severe abnormalities. However, most patients had nonspecific-type dyspepsia or persistent symptoms after therapeutic trials of acid suppression. CONCLUSIONS: Dyspepsia may be an atypical presentation of pancreatic disease in patients with persistent or nonspecific symptoms. Endosonography may be useful to screen for pancreatic disease in patients with persistent dyspepsia.

Adult↗
PubMed2000

CT or EUS for the initial staging of esophageal cancer? A cost minimization analysis.

BACKGROUND: Patients with advanced (T4 and/or M1) esophageal cancer are offered palliative therapy. Computed tomography (CT) is sensitive for distant metastases but is less sensitive than endosonography for T4 disease and celiac lymphadenopathy. The aim of this study was to determine whether initial CT or endosonography costs less to diagnose advanced esophageal cancer. METHODS: A decision model compared the costs of the 2 strategies. Sensitivity analysis and threshold analysis were used to identify the most important determinants of the overall cost of identifying advanced disease. RESULTS: Initial CT is the least costly strategy if the probability of finding advanced disease by initial CT is greater than 20%, if the probability of finding advanced disease by initial endoscopic ultrasound (EUS) is less than 30%, or if the cost of EUS is greater than 3.5 times the cost of CT. However, in our referral center population, endosonography found advanced disease more frequently than CT (44% vs. 13%; p < 0.0001) and the least costly strategy was initial endosonography (expected cost $804 vs. $844). CONCLUSION: CT remains as the initial staging test of choice in most clinical settings. However, in referral centers, initial EUS may be reasonable, but individualized model inputs must be obtained before reliable conclusions can be drawn.

Adult↗
PubMed2000

1999 ASGE endoscopic ultrasound survey. ASGE Ad Hoc Endoscopic Ultrasound Committee.

BACKGROUND: Gastrointestinal endoscopic ultrasound (EUS) has become an important imaging modality for the diagnosis and staging of gastrointestinal disorders. This study assessed current EUS practice, training, coding, and reimbursement in the United States. METHODS: A direct mail survey was sent to members of the American Society for Gastrointestinal Endoscopy. RESULTS: There were 115 American respondents. The median age was 39 years, 57% were in academic practice, and 84% performed endoscopic retrograde cholangiopancreatography. The median number of EUS procedures performed was 200. In the preceding year, the median number of upper EUS was 60, lower EUS 10, and EUS/fine-needle aspiration 3. The most common indication was evaluation of esophageal or gastric lesions. Forty-six (40%) trained an average of 0.4 advanced fellows in EUS during the prior year. Of endosonographers involved in training, 53% thought formal training was necessary, for a median of 6 months and 100 procedures; 82% did not know whether they were reimbursed for EUS. There was great variation in the use of current procedural terminology (CPT) codes for lower EUS and upper EUS/fine-needle aspiration. CONCLUSIONS: EUS in the United States in 1999 is performed mostly by young, academic, interventional endoscopists. Diagnostic upper EUS is most commonly performed. Few new endosonographers are being trained. There is great variability in CPT coding of lower EUS and EUS/fine-needle aspiration procedures.

Adult↗