New Measurement Methods and a Randomized Comparison of Force ...

Abstracts

T1396 Using the Video Endoscope Prototype Olympus XGIF-N160Y1 for Transnasal Gastroscopy: A Pilot Study of Feasibility and Tolerability Italo Stroppa, Claudio Tosti, Cinzia Razzini, Sabrina Mazzocchi, Francesco Romeo, Francesco Pallone Background and Aim: The video endoscope Olympus XGif-N160Y1 (outer diameter:4.9 mm, total length:1410 mm, working length:1100 mm) is a prototype (PT) with only ‘‘up-down’’ movement, metallic distal tip and a deflexion capability of 210  up and 180  down. The aim of the study was to assess feasibility and tolerability of transnasal gastroscopy (TN) using this prototype. Methods: 50 consecutive patients eligible for TN were enrolled in the study (25 men, 25 female, age: 49 G 17 years). InIclusion criteria were: indication for gastroscopy, history of prior conventional gastroscopy and age O 14 years. All patient gave informed consent. Hamilton A scale was used to assess patients anxiety before endoscopy in all patients. A questionnaire was administered to all patient soon after TN examination was completed to explore patients satisfaction and preference for conscious sedation. Cardiorespiratory parameters (oxygen saturation, one-lead electrocardiogram) were recorded during endoscopy. Blood pressure was measured in different phases during the exam (baseline, esophagus, stomach, duodenum) and after exam. Cardiorespiratory parameters variations in each phase of the exam were compared by one way analysis of variance. Feasibility and image quality were evaluated by operator on a subjective scale. Results: Endoscopy was performed with a transnasal approach in every patient without complications. Procedure time was 5 G 3 minutes. All segment down to the second duodenal portion were visualized. In all patients biopsy samples were taken from both the antrum and the gastric body. Images quality was excellent in all examination as assessed by the subjective endoscopist’s evaluation. Anxiety was absent in 24 patients, mild in 15, moderate in 4 and need to treatment in 4. After satisfaction questionnaire was administered it appeared that none of the 24 patients with no anxiety and one of the 26 with any level of anxiety would have preferred conscious sedation. Only one patient reported pain at instrument insertion and during endoscopy. No significant changes in oxygen saturation and blood pressure occurred during the exam. Heart rate and rate-pressure product increased significantly during the endoscopy (p ! 0.01) and returned to baseline at the end of the exam. No ST-T changes or serious arhythmias occurred. Conclusions: Data of this pilot study show that unsedated transnasal gastroscopy by the prototype Olympus XGIF-N160Y1 is feasible and well tolerated by patients.

T1397 New Measurement Methods and a Randomized Comparison of Force Transmission Using Flexible Endoscopes and Instruments Before and After the Application of ShapeLockÔ Technology Paul Swain, Richard Ewers, Ruey Peh, Vahid Sadaat Background: A major limitation to the development of flexible endoscopic surgery is the limitation of force which can be exerted on tissue by endoscopes and accessories, especially when retroflexed. The flexibility of endoscopes and the instruments passing through them also reduces precision and control when compared with rigid surgical instruments and is difficult to measure. Aims: 1: To develop test equipment to measure force transmission on tissue by endoscopes and accessories at a wide range of angles; 2: to compare force transmission and stability of flexible endoscopes and insturments before and after the application of ShapeLock (SL) technology (USGI Medical). Methods - Test Equipment and Experiment Design: A double trampoline-like rig was constructed on a sensitive balance which allowed measurements of force exerted by endoscopic instruments on tissue at different angles. The device could control for the effect of gravity and mass of the endoscope or accessory. Devices were developed to allow force gauges and balances to measure the forces exerted by the endoscopist on the endoscope and the endoscopic instruments and to measure the force transmitted to the tissue by the instrument in the endoscope. Results: Peak push force exerted on the endoscope tip was 18.4 g @ 90o w/o SL, 262 g w SL. Mean increase in force transmission (MIFT) Z 1434% (p ! 0.05), 10 g @ 45 o w/o SL, 234 g w SL, (MIFT) Z 2340% (p ! 0.05). Peak push force on biopsy forceps on tissue was 13.4 g @ 90o w/o SL, 130 g w SL. Mean increase in force transmission (MIFT) Z 970% (p ! 0.05) and 14.2 g @ 45o w/o SL, 78 g w SL. Mean increase in force transmission (MIFT) Z 549% (p ! 0.05). Peak pull force on biopsy forceps on tissue was 89 g @ 90o w/o SL, 241 g w SL. Mean increase in force transmission (MIFT) Z 271% (p ! 0.05) and 94 g @ 45o w/o SL, 177 g w SL. Mean increase in force transmission (MIFT) Z 188% (p ! 0.05). Buckling of endoscope tip or forceps was a common cause of poor force transmission and instrument instability. Conclusions: 1. Development of new methods to measure transmission of forces exerted on tissue by flexible endoscopes and accessories allowed measurements in a range of common positions. 2. Using ShapeLock technology, push force was increased by up to 23x at the endoscope tip, 10x with biopsy forceps and 2.7x with biopsy pull force. 3. A better understanding of the limitations of transmission force and tip stability can lead to improved designs for therapeutic and diagnostic endoscopy.

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T1398 Endoscopic Submucosal Dissection (ESD) Method for Colorectal Laterally Spreading Tumor Larger Than 20 mm in Diameter Shinji Tanaka, Shiro Oka, Iwao Kaneko, Mayuko Hirata, Ritsuo Mouri, Masaharu Yoshihara, Kazuaki Chayama Recently endoscopic submucosal dissection (ESD) for early gastric cancer has been performed commonly at many institutions in Japan. As colorectal wall is very thin, ESD tends to cause the high incidence of complication such as perforation, however, several institutions try to apply ESD also for colorectal neoplasia. The Aim of this study is to clarify the clinical usefulness and safety of ESD for large colorectal tumor. Materials and Methods: We performed ESD for 33 cases of large colorectal tumor (so-called LST: laterally spreading tumor; Kudo et al, Endoscopy 1993) at Hiroshima University Hospital until August in 2004. For ESD, Hook, Flex or IT knife and transparent disposable distal attachment were used. Glycerin (10%) was injected to surrounding submucosa of the lesions for incision around the lesion. Sodium hyaluronate with indigo carmine was used for submucosal injection to practice submucosal dissection. As high-frequency generator, ICC 200 (ERBE, Tubimgen, Germany) was used, which is furnished not only with end-cut modes for incision but also with multiple coagulation modes. We use the generator as follows: endo-cut mode effect 2, 120 W for mucosal incision; forced mode, 40 W for submucosal dissection and soft mode, 50 w for hemostasis. Using these lesions, en bloc resection rate, operation time, and complication were analyzed. Results: Cases consisted of 11 carcinomas (m 9 cases, sm 2 cases) and 12 adenomas. Seventeen cases located at rectum and 16 cases at colon. Average diameter of lesions was 29.5 G 12.5 mm. Average operation time was 78.2 G 51.2 min (35w160 min). Rate of histological complete en bloc resection was 78.8% (26/33). Reasons of incomplete or piecemeal resection were complication or existence of submucosal fibrosis. Complication was perforation occurred in 6 (18.2%) of 33 cases. Two were distinct perforation at import period of ESD method using IT knife at Hiroshima University Hospital, which were surgically operated. Four cases were all microperforation using Hook knife and could be treated conservatively. Bleeding after ESD was not seen in all cases. No residual tumor was detected in follow-up examination in all cases. Conclusions: ESD is a useful new method for endoscopic en bloc resection of large lesion. Incidence of perforation in ESD should be reduced by adequate choice of device and technical/instrumental progress. Also, we have to clarify the correct indication of ESD for colorectal lesion in the near future.

T1399 Optical Coherence Tomography to Identify Villous Morphology in Patients with Suspected Celiac Disease Enzo Masci, Benedetto Mangiavillano, Luca Albarello, Paolo G. Arcidiacono, Alberto Mariani, Mario Guslandi, Maria C. Petrone, Claudio Doglioni, Pier A. Testoni Introduction: The prevalence of celiac disease (CD) is currently increased compared to our experience in the past. Serological findings are very useful in increasing our screening capacity, but histology remains the gold standard in the diagnosis of CD. OCT is a new imaging technique, similar to B-mode ultrasound (US), but its resolution is far greater (5-10 `m) ı near to histology. No data are actually available on the use of OCT in the small intestine and, in particular, in the diagnosis of CD. Aim & Methods: Aim of our study is to test the utility of OCT in patients with serological positivity to antigliadine and antiendomisial antibodies undergone to esofago-gastro-duodenoscopy (EGDS) for histological diagnosis. We enrolled 5 patients with suspected CD and 5 normal subjects who underwent EGDS for dyspepsia. OCT scanning of descending duodenum was performed during diagnostic EGDS and biopsies of the same area of the duodenum were taken. Evaluation of OCT images and histological specimens was blind, the analysis being performed independently by a gastroenterologist and a pathologist. Three patterns of intestinal villous morphology were considered (1 Z no atrophy; 2 Z mild atrophy; 3 Z total atrophy). Results: We obtained the same results about villous pattern into the two group with the two techniques, and similar data about mean villous height in celiac group (0.25 mm in the OCT measures vs 0.28 mm in the histological measures) but with an increased value in the data performed by OCT into the normal subjects group (mean villous height: 0.70 mm vs 0.40 mm). Conclusions: There is a good concordance between histology and OCT to identify villous pattern of CD. However measurements of intestinal villous height show an increased value in OCT, particularly in control patients, possibly due to the villous rhitidosis after histological handling. OCT appears to be a promising technique to identify CD during endoscopy. An unsolved problem remains the impossibility to detect, at present, lymphocitic infiltrate and crypt’s hypertrophy, two specific tools in the diagnosis of CD. Our preliminary data must be confirmed by further studies.

Volume 61, No. 5 : 2005 GASTROINTESTINAL ENDOSCOPY AB241