Rig S. Patel

3892 How many supervised procedures does it take to become competent in eus?-results of a multicenter three year study.

Background: The amount of experience required to train new endosonographers is unknown. Competency in technical performance is likely to precede interpretive competence. Methods: Over a 3 year period, recognized experts in EUS provided one on one proctorship; evaluated the performance of new trainees in the specific categories listed below; and rated each procedure category as 0=Failed; 1=Unsatisfactory; 2=Satisfactory; 3=Excellent. Competency was defined as achieving a consistent score of 2. Results:10 third tier fellowship trainees and 2 PGY 6 trainees were evaluated. All were male. Only one had performed EUS prior to beginning his training. None had prior abdominal US experience. 10/12 were trained in ERCP. Mean number of ERCPs performed before EUS training was 229 ( SD 167). The median (range) of the number of EUS procedures required for competency is listed for the following categories: Esophageal Intubation 1(1-21), Pylorus Intubation 2(1-14), Duodenal Intubation 2(1-23), Esophageal wall visualization 10(1-36), Gastric wall 15(1-47), Mediastinum 10(1-33), Celiac axis 25(8-36), Pancreas body and tail 26(1-34), Pancreas head 34(15-74), CBD/PD 55(13-135), Ampulla 54(13-134) , Normal anatomy interpretation 54(9-92), and Pathology interpretation 60(16-134). The number of procedures needed to successfully visualize the head, tail and body of the pancreas was not different among the trainees who had performed more than 100 ERCPs compared to those who had performed less (p>0.05). In addition, the number of procedures needed to adequately interpret normal anatomy or EUS related pathology was not different among the two groups. Conclusions: With intensive hands-on experience and tutelage by an expert in a facility performing a high volume of EUS procedures, a trainee may become competent to perform EUS within a relatively short time-period. There is, however, a broad range in the ability to interpret normal anatomy and pathology. This information may alter the current pattern of advanced training and also be of importance to private practitioners wishing to develop skills in EUS. This study was support by a grant from the American Digestive Health Foundation.

4533 The detection of celiac lymphadenopathy in esopahgeal cancer by endosonography is synonymous with malignant involvement.

Background: EUS-guided FNA is the most accurate method of confirming loco-regional malignant lymphadenopathy. The additional yield of FNA beyond endosonographic characteristic is unknown. Aims: 1) To determine if the detection of a CLN by EUS, independent of FNA, indicates malignant involvement. 2) To evaluate the accuracy of EUS in detecting CLN metastasis. Methods:We reviewed all cases of esophageal cancer that underwent EUS at our institution from 1/26/94 to 11/1/99. All staging was performed with a radial scanning echoendoscope (UM-20 or UM-130). FNA was performed of all accessible CLN with a linear scanning echoendoscope (UC-30 P, UCT-30, UM-30P). Patients were included in this study if they underwent surgery (n= 59), or if they had FNA of a celiac LN (n=44). The accuracy of EUS compared to cytology or histology was subsequently determined. Results: 103 patients with esophageal cancer met inclusion criteria. Seventy eight percent were male and 76% were Caucasian. Fifty five percent had adenocarcinoma of the esophagus and 79% of the tumors were confined to the distal esophagus or GE junction. Twenty five percent underwent dilation to 45 Fr to complete the examination. No complications were encountered. EUS imaging identified 48 true positive patients with CLN, 6 false positive, 14 false negative and 35 true negative. Therefore, the sensitivity of EUS in detecting CLN was 77% (95% CI, 67-88), the specificity 85% (95% CI, 75-96), the negative predictive value 71%, and the positive predictive value 89%. The overall accuracy of EUS was 81%. EUS FNA confirmed the nature of a CLN in 88% of the cases. Seventy eight percent (21/27) of EUS-detected CLN ≤ 1cm were malignant while 100% (25/25) of EUS-detected CLN >1 cm were malignant (p=0.02). Conclusions: Approximately ninety percent of CLN detected by EUS in patients with esophageal cancer are ultimately proven to be malignant. Since cytological proof of malignant involvement is critical in clinical decision making, all visible CLN should undergo FNA. IF a CLN (>1 cm) is imaged by EUS and FNA is not technically feasible, this study suggests that the patient should be considered to have CLN malignant involvement and should be managed accordingly.

4668 Is magnetic resonance cholangio-pancreatography with cholecystokinin useful in identifying patients with sphincter of oddi dysfunction?

Sphincter of Oddi manometry (SOM) is the standard method of diagnosing SOD. SOM is invasive, can be technically difficult and associated with complications. MRCP with CCK stimulation may provide useful information relating to sphincter of Oddi function. AIM: Evaluate the sensitivity/specificity of CCK-MRCP in predicting the results of SOM in patients with clinically suspected SOD (type III). METHOD: Data from consecutive patients referred for SOM who had CCK-MRCP prior to SOM were analyzed. All MRCP studies were reported by one radiologist who was blinded to the findings of SOM. Patients with prior therapy to the papilla or known pancreaticobiliary malignancy or stricture were excluded. Equivocal/failed MRCP or SOM were excluded from analysis. SOM was performed using a standard 5 F perfused, aspirating catheter (Wilson-Cook, Winston-Salem, NC); SOD was diagnosed if the mean pressure from two leads was greater or equal to 40 mmHg. MRCP was performed with oblique coronal singleshot breath-hold, 5cm slabs (8000/150//135), FOV-24 cm. Scans were performed before and 20 mins after initiation of the CCK infusion (0.02mcg/Kg, in 6ml saline, 0.1ml/sec). CCK-MRCP was abnormal if the common bile duct increased in diameter post-CCK. RESULTS: Of 25 patients (mean age 38yrs., range7-74yrs, M/F=5/20), 18 biliary and 18 pancreatic SOM studies were analyzed; CCK-MRCP was inadequate in 2 patients. Of all 12 patients, CCK MRCP was abnormal in 4 of 6 patients with abnormal biliary SOM (sensitivity 67%) and was normal in 7 of 12 patients with normal biliary SOM (specificity 58%). Of the 5 patients with an intact gallbladder, CCK-MRCP was normal in all 3 patients with normal biliary SOM and abnormal in both patients with abnormal biliary SOM. The sensitivity and specificity of CCK-MRCP in predicting abnormal biliary SOM in post- cholecystectomy patients was 50% and 44 % respectively. There was no association between pancreatic SOM and CCK-MRCP. CONCLUSION: 1] The overall sensitivity and specificity of CCK-MRCP in predicting abnormal biliary SOM was 67% and 58% respectively. 2] The sensitivity and specificity were 100% in the small sub-group of 5 patients with the gallbladder in situ. This study is on-going to further evaluate these novel findings.

4465 Scheduled vs. as required stent exchanges for malignant biliary obstruction. a prospective randomized study.

Background: The best strategy for stent exchange in malignant biliary obstruction is not known. Some experts advocate routine prophylactic stent exchange every 3-4 months, a strategy which might lead to many unnecessary procedures. Aim: A prospective randomized study comparing 2 commonly practiced strategies: scheduled vs. as required stent exchanges. Methods: Pts. requiring biliary stenting for malignant obstruction were randomized to either (i) scheduled exchanges every 4 months or earlier if stents occluded (SCH) or (ii) exchanges only when stents occluded (PRN). End points were either metal stenting, surgery, death or resolution of stricture not needing stenting. LFTs were monitored monthly in both gps. Occlusion was defined as a doubling of nadir alkaline phosphatase or bilirubin. Results: Of the 69 pts. recruited 5 were excluded (4- benign; 1-immediate surgery). 30 pts. (9 M) were randomized to SCH and 34 pts. (15 M) to the PRN arm. The 2 gps. were comparable in all respects (SCH : PRN) mean ages (69:72); diagnoses (%) pancreatic Ca (73 : 76), cholangioCa (10 : 14), metastases (13 : 9) and ampullary Ca (1 : 0); mean comorbidity indices (0.83 : 0.97); & stent diameters (≥10 Fr). Number of ERCPs per pt. in the 2 gps. was not different, 2.1(SCH) vs 2(PRN). Number of stents per patient [(SCH : PRN): 1 stent (15:15); 2 stents (4:10); 3 stents (5:5); 4 stents (3:2); 5 stents (3:2)] and end points [death (22:26); metal stenting (6:7); surgery (1:0); misc (1:1)] were similar. Indications for metal stenting (SCH:PRN) duodenal stenosis (3:7) and rapid reocclusion (3:1) were similar. 43% pts. (SCH) and 47% pts. (PRN) died with patent stents. The mean stent survival was 90 d (SCH) vs 97 d (PRN), (p=NS). There was no difference in the survival time of each serial stent between the two gps. There was 1 episode of stent related cholangitis leading to death in the PRN arm on day 108 (T=3.82; p>0.05). There was no difference in the number of episodes of cholangitis; 10 in SCH vs 15 in PRN (T=1.29763; p>0.25). Time to death or other endpoints was not different in the two gps. (p=0.99). Conclusion: (1) There is no difference in measured outcomes when plastic stent exchanges are performed electively every 4 months or on an as required basis for biochemical occlusion in malignant biliary obstruction. (2) Using biochemical occlusion rather than clinical occlusion may result in a lower stent related mortality than previously reported. (3) Other factors (e.g. physical proximity, personal preference) should be used when selecting a strategy.

3895 Randomized controlled trial of eus guided fine needle aspiration technique for confirming malignant lymphadenopathy.

Background: The optimal method for performing EUS guided FNA of malignant appearing lymph nodes (LN) is unknown. Histological evidence suggests that malignant cells are preferentially located in the edge of LNs. Improved techniques may increased diagnostic accuracy, and reduce procedure time and costs. Objetives: To determine the impact of the number of FNA passes, FNA-suction, FNA-location (center or edge), and examination of needle effluent on diagnostic yield and specimen quality. Methods: Consecutive EUS-FNA of LN were randomized in a 2x2 factorial design to suction (10cc syringe) or no suction, and to aspiration from the center or edge of the LN. Individual LN were sampled with all four possible combinations of suction and location for 30 seconds each FNA pass. Each aspirate was examined by a blinded cytopathologist for cellularity, and malignancy after Papanicolaou staining. Five cc of needle effluent from each pass were pooled and compared to the cytological diagnosis. Results: One hundred forty five FNA passes were performed on 32 LN in 27 patients. Ten LN were confirmed by cytology to be malignant, 3 were suspicious, 6 were confirmed by cytology and surgery to be benign, and 13 had normal cytology. Eighty percent of malignant specimens were obtained on the first FNA pass, and 100% were obtained in the first 3 passes (mean number of passes 4.5, range 2-8) regardless of the bedside cellularity of the specimen. Sampling the edge of the LN (compared to the center) did not improve the identification of malignant cells (Relative Risk 0.98, p=0.8) nor did it improve the specimen cellularity (RR=0.93, p=0.8). The use of suction did not improve the diagnostic yield of malignant cells (RR=1.1, p=0.4) nor cellularity (RR=1.3, p=0.3). The use of suction worsened of the quality (bloodiness) of the specimen (p value for trend 1cm) LN. Conclusion: This study suggests that three FNA passes are sufficient to diagnose malignant lymphadenopathy. The current standard use of suction significantly worsens the quality of the aspirate due to excessive bloodiness and does not improve diagnostic yield of EUS-FNA. FNA can be performed from either the center or edge of LN with equal yield. Dr. Wallace was supported by the American Digestive Health Foundation, Wilson Cook Award

4589 How much experience is required to correctly interpret eus features of chronic pancreatitis? a multicenter prospective trial of third tier eus trainees compared to a consensus of experts.

Background: The amount of experience required to train new endosongraphers is unknown. Interpretative and procedural skills are likely acquired at different rates. Methods: Forty five standardized examinations (Olympus UM-20 or UM-130 at 7.5 mHz) of the pancreas were videotaped including patients with and without suspected pancreatic disease. Eleven experienced (“experts”) endosongraphers who had performed more than 1000 EUS examinations each, independently rated all examinations for nine separate features of chronic pancreatitis (hyperechoic foci, strands, lobularity, cysts, stones, duct dilation, duct irregularity, hyperechoic duct margins, and visible side branches), as well as a global diagnosis of CP. Consensus diagnoses for each feature and global assessment was considered when >90% of the experts agreed on the presence or absence of a feature. Ten EUS trainees independently rated the same videotape and were compared to the consensus cases. An answer was considered correct when the trainee agreed with the consensus diagnosis. Results: Ten trainees from three separate third-tier EUS training programs had performed a median of 150 (range 50-1200) lifetime EUS examinations, and 40 (range 0-100) lifetime chronic pancreatitis EUS examinations. Out of 450 features (45 examinations x 10 features), there was consensus by the expert panel on 206. The trainees correctly scored a median of 190 (range 181-200) out of 206. The score was strongly and positively correlated with the number of chronic pancreatic EUS examinations (R = 0.62, p= 0.05), and weakly correlated with total pancreatic examinations (R= 0.42, p = 0.22), and total EUS examinations (R = 0.47, p = 0.17). After performing at least 15 examinations, all trainees correctly diagnosed more than 90% of features. Scores greater than 95% were reached after performing 40 examinations. Conclusions: Skill in interpreting EUS features of chronic pancreatitis is strongly correlated with experience. Interpretive competence, as measured by agreement with an expert panel, is reached after performing only 15-40 chronic pancreatitis examinations in a supervised, third tier training program. In evaluating chronic pancreatitis with EUS, procedural skills as opposed to interpretive skills, are more likely to be the limiting factor in EUS training. Dr.Wallace was supported by the American Digestive Health Foundation, Wilson Cook Award

4660 Patients with clinically suspected sphincter of oddi dysfunction are more likely to have pancreatic sphincter hypertension if pancreatic ductography is abnormal.

The incidence of pancreatic ductographic abnormalitites (PDA) in patients with normal and abnormal pancreatic orifice manometry is not known. AIM: Evaluate the incidence of (PDA) in patients with clinically suspected SOD who undergo pancreatic manometry (PSOM). METHOD: The MUSC GI Trac data base was reviewed for consecutive patients with clinically suspected SOD who had successful unequivocal PSOM between 2/94 and 11/99. Patients with pancreas divisum, prior pancreatic duct or orifice therapy, and failed/inadequate pancreatic ductography were excluded from analysis. The ductographic findings of duct dilatation, duct irregularity and irregular side branch changes, were compared individually and as a group with the findings of PSOM. PSOM was performed using a standard 5 F aspirating catheter (Wilson-Cook,Winston-Salem, NC) and PSH diagnosed if the mean pressure from two leads was >40 mmHg. RESULTS: Of 833 patients (mean age 46.3 yrs, range 16-86yrs., M/F 218/615), 429 (52%) had abnormal PSOM (ie PSH) and 431 (52%) had at least one PDA. At least one PDA was present in 248/429 (58%) of patients diagnosed with PSH, and 45% (181/402) with no PDA had PSH (p

4661 Do pancreatic features identified with endoscopic ultrasound correlate with sphincter of oddi manometry in patients with clinically suspected sphincter of oddi dysfunction? an evaluation of 462 patients.

SOM is the accepted method for diagnosing SOD. EUS can evaluate anatomical features of the pancreas. The role of EUS in the evaluation of patients with clinically suspected SOD particularly in predicting the findings of SOM, is undefined. AIM: Evaluate if EUS assessment of the pancreas correlates with SOM in patients with clinically suspected SOD. METHOD: Patients with clinically suspected SOD who underwent EUS prior to SOM between 2/94 and 11/99 at MUSC were included for analysis. Patients with pancreas divisum, prior therapy to the major papilla, or inadequate SOM or EUS were excluded. EUS features of pancreatitis ( parenchymal : foci, strands, lobularity, cysts, and ductal : hyperechoic and irregular duct margins, calcification/stones, visible side-branches and duct dilatation) were compared with the SOM diagnosis of the biliary (BSOM) and pancreatic (PSOM) orifices. All EUS examinations were blinded to the findings at SOM. SOM was performed using a standard 5 F aspirating catheter and SOD diagnosed if the mean sphincter pressure from two leads was >40 mmHg. EUS was performed using a radial echoendoscope (Olympus UM-20, UM-130) at 7.5 MHz. RESULTS: Of 462 patients (mean age 45 yrs. range16-85yrs., M/F 137/325), 372 and 370 underwent unequivocal PSOM and BSOM respectively after EUS. Of the 176 patients with abnormal PSOM, 54% (n=95) had a total >4 EUS features of pancreatitis; 46% (89/194) with normal PSOM had 3 or less features (p=1). Of patients with no EUS features, 48%(25/52) and 52% (27/52) had normal and abnormal PSOM respectively (p=0.55). Similarly there was no correlation between BSOM (148 abnormal) and the total number of EUS features. The number of parenchymal or ductal EUS features was unrelated to BSOM or PSOM. CONCLUSIONS 1] Neither the total number nor the number of parenchymal or ductal EUS features of pancreatitis predict the findings of SOM in patients with clinically suspected SOD. 2] A normal EUS examination (i.e. no features) does not exclude SOD.

3491 Preliminary experiences of three-dimensional endoscopic ultrasonography in the united states.

INTRODUCTION: The advent of low cost computer power has greatly impacted body imaging resulting in a proliferation of technologies incorporating 3-D reconstruction. AIM: To image a variety of UGI lesions with a prototype 3-D EUS catheter probe to determine its potential clinical applications. METHOD: The 3D-EUS imaging system (Olympus Optical, Tokyo) consists of a 12 and 20 MHz ultrasonic probe (UM-3D2R, UM-3D3R), a motor unit, an ultrasound processor (EU-M30), and a computer for image processing (EU-IP2). Scanning and storing time is 4 to 13 sec. The ultrasound probe is housed in a clear sheath filled with water. The motor moves the probe radially (360°) and linearly (4cm). Images are stored and processed later. In all cases, the radial and linear images were reviewed and judgment was rendered as to whether combined imaging provided clinical benefit. Esophageal cases were performed using a condom placed over the end of a two channel endoscope. RESULT: Between 5/99 and 11/99, 13 3-D EUS cases were performed (2 esophageal cancer, 3 Barretts esophagus, 4 esophageal SMT, 1 gastric SMT, 1 mucinous ductal ectasia, 1 common bile duct stricture). The simultaneous display of linear and radial images made imaging and interpretation of images of SMT easier but did not provide unique and significant advantages. Imaging and evaluation of Barretts esophagus and biliary strictures was significantly better with the 3-D system because of the volume of area that can be scannedfrom a single position. CONCLUSION:We suggest that the simultaneous linear and radial images produced by this instrument may improve diagnosis in some circumstances. Prospective trials based on this data are ongoing. Volume rendering will be possible in the near future which may further expand the application of 3-D EUS.

6984 A dilated pancreatic duct at ercp can be associated with a lower incidence of post-ercp pancreatitis (pep).

Background: The etiology of PEP is probably multifactorial. Pancreatic stenting has been shown to reduce the incidence of PEP in selected patients. We hypothesized that normal diameter ducts are more likely to become occluded by edema and hence associated with PEP. The relationship between the findings of pancreatic ductography and PEP is not known. Aim: Evaluate if there is an association between pancreatic duct dilatation (PDIL) and PEP. Methods: The MUSC GI Trac database was reviewed for patients who had successful pancreatography. Patients with cancer, stricture, stones and prior pancreatic duct or orifice therapy were excluded. The incidence of PEP was evaluated in patients who did or did not have (PDIL). Patients were sub-grouped if they had a pancreatic stent placed and/or concomitant biliary sphincterotomy (BSx). Results: Of 3298 patients (mean age 49yrs., range 10-89yrs., M:F= 3:7), PEP occurred in 150 (5%). A dilated duct was noted in 801 patients. The incidence of PEP in all patients with PDIL was 3% (23/801) compared to 5% (127/2497) in those with no PDIL, p=0.008. The incidence of PEP in patients with and without BSx, pancreatic stenting and PDIL, is tabulated: Of all patients who had a pancreatic stent placed (n=887), there was no statistical difference in the incidence of PEP in those with PDIL (3%, 10/316) Vs no PDIL (5%, 27/571). CONCLUSIONS: 1] The overall incidence of PEP is lower if the pancreatic duct is dilated. 2] The presence of duct dilatation in patients who do not undergo BSx or PD stenting is associated with a lower incidence of PEP.