Su1560A Novel Forward-Viewing Radial-Array Echoendoscope With aNew Application: Differentiation Between Ulcerative Colitis (UC)and Crohn’s Disease (CD) in Colon Beyond RectumSatimai Aniwan*, Pradermchai Kongkam, Rungsun Rerknimitr,Sombat Treeprasertsuk, Wiriyaporn Ridtitid,Phonthep Angsuwatcharakon, Pinit KullavanijayaInternal Medicine, Chulalongkorn University, Bangkok, ThailandBackground: Colonoscopy has a limited capability to distinguish Crohn’s disease(CD) from ulcerative colitis (UC). CD has a characteristic trans-mural invasionthrough colonic wall. Endoscopic ultrasound (EUS), the best tool at present forintestinal wall delineation, is theoretically expected to be able to differentiatebetween these 2 diseases. Unfortunately, the current oblique-viewing radial-arrayEUS has a limitation in viewing and precludes deep intubation of EUS probe intothe colon beyond rectum. With a newly designed forward-viewing radial-arrayechoendoscope (radial Scan Ultrasonic Video Endoscope EG-530UR2 (FUJIFILMCorporation, Tokyo, Japan) and Ultrasound Processor SU-8000 (FUJIFILMCorporation, Tokyo, Japan), the scope can readily be passed to the cecum andcan be used to endosonographically illustrate colonic wall. At the time of writingwe believe we are the first group to use this new equipment to study its efficacyin differentiating these 2 diseases. Methods: Patients with confirmed CD and UCin King Chulalongkorn Memorial hospital, Bangkok, Thailand, from 1st August to31st October 2012, were prospectively recruited into the study. Bothcolonoscopy and colon EUS were performed. The endoscopic grading of severitywas assessed by Baron Index for UC, and Crohn’s Disease Endoscopic Index ofSeverity for CD. EUS findings of total wall (TW) thickness, muscularis proria(MP) layer thickness, irregular interface between sub-mucosa (SM) and MPlayer), from the most active colonic lesions were recorded and comparedbetween the 2 groups. Results: Twenty-seven patients (8 CD, 19 UC) wereenrolled. CD patients had significantly higher TW thickness (6.4�2.5 vs. 3.4�1.0mm; p�0.001), SM wall thickness (2.4�1.4 vs. 1.4�0.5 mm; p�0.015), and MPwall thickness (2.3�1.6 vs. 1.0�0.4 mm; p�0.003) than UC patients. Irregularinterface between SM and MP layer was detected in 63% of CD patients, whereasnone of the UC patients was detected. Fusion of all 5 layers was demonstrated in2 patients with CD. Summary: The new forward-viewing radial-arrayechoendoscope demonstrated significantly thicker colonic wall in CD than UC. Italso shows a characteristic fusion of all 5 layers in CD. Conclusion: The newforward-viewing radial-array echoendoscope is a promising tool fordifferentiating CD from UC. We will conduct a larger systematic study to validatethe real accuracy and usefulness of this new equipment.

Table 1. EUS parameters between CD patients and UC patients

EUS parametersCD

(n�8)UC

(n�19) P value

Total wall thickness (mm) 6.4�2.5 3.4�1.0 p�0.001Submucosal layer thickness (mm) 2.4�1.4 1.4�0.5 p�0.015Muscularis propria layer thickness

(mm)2.3�1.6 1.0�0.4 p�0.003

Irregular interface betweensubmucosa and muscularispropria layer (number and %)

5(63%) 0(0%) p�0.001

Su1561Endoscopic Ultrasound of the Colon for Evaluation of MucosalHealing/Early Therapy Response of Anti-TNF-� Therapy inPatients With Ulcerative Colitis - First Results of a Pilot StudyMark Ellrichmann*, Johannes Bethge, Susanna Nikolaus, Alexander Arlt,Stefan Schreiber, Annette Fritscher-RavensExperimental Endoscopy, Internal Medicine I, University HospitalSchleswig-Holstein, Campus Kiel, Kiel, GermanyIntroduction: Evaluation of mucosal healing in acute ulcerative colitis (aUC) isimportant, but the assessment of inflammatory changes is based on acombination of clinical, endoscopic and histological activity indices, which oftenfail to deliver early information about therapy response. In an earlier study wedemonstrated that Endoscopic ultrasound of the colonic wall (EUSc) allows exactquantification of the total wall thickness (TWT), differentiation of the differentlayers and can therefore accurately quantify the grade of inflammation. Aim: Toevaluate EUSc in patients with aUC undergoing treatment with Anti-TNF-�(adalimumab,(AD)) for possible detection of early therapy response. Methods:Eleven consecutive patients with aUC were examined prior and 1, 4 and 12weeks after initiation of AD-therapy using forward-viewing radial echoendoscope(Pentax-Hitachi, Japan). Mucosal, submucosal and total wall-thickness (TWT)were measured by EUSc in the mid sigmoid. Results were compared to 10healthy controls (HC) undergoing screening colonoscopy. The examiners wereblinded to the macroscopic inflammation scores. EUS-results were correlated tothe Mayo-score and histological inflammation scores (HIS). Results: TWT in HCwas 1.71�0.02mm with clear differentiation of the different layers; in aUC it was3.4�0.87mm (p�0.001). In patients with clinical response to therapy (n�10)TWT was reduced by 27.9% (TWT7d�2.5�0.2mm; p�0.01) within one weekwhen compared to baseline levels. In contrast, Mayo scores (2.1) did not show areduction in this period (Mayobaseline�2.2). After 4 weeks a further reductionof (12%) of TWT (TWT28d�2.2�0.2mm) was observed, then accompanied bysignificant reduction of the Mayo-score (Mayo28d�1.2�0.2). Prior to therapythere was a strong correlation of TWT and Mayo-score. In contrast, nocorrelation was observed 1 week after AD-therapy (p�0.05). During the entirecourse of AD, a positive relation between TWT and HIS (r�0.65; p�0.001) wasseen.In one patient no reduction of the TWT was observed within 1 week oftherapy. This patient was defined to be a non-responder to AD-therapy 6 weekslater. Discussion: TWT measured by EUSc precisely quantifies the level ofinflammation in patients with aUC and proved reliable for the evaluation of earlytherapy response. It may become an important diagnostic tool for the judgementof mucosal healing in AD-therapy.

Su1562A Novel Forward-Viewing Radial-Array Echoendoscope With aNew Application: T Staging of Colon Cancer Beyond Rectum: aProspective Blinded Feasibility StudySittikorn Linlawan*1, Pradermchai Kongkam1, Rungsun Rerknimitr1,Chucheep Sahakitrungruang2, Jirawat Pattana-Arun2,Supakij Khomvilai2, Naruemon Wisedopas3, Narisorn Lakananurak1,Satimai Aniwan1, Wiriyaporn Ridtitid1, Pinit Kullavanijaya1

1Internal medicine, Chulalongkorn university, Bangkok, Thailand;2Surgery, Chulalongkorn university, Bangkok, Thailand; 3Pathology,Chulalongkorn university, Bangkok, ThailandIntroduction: Preoperative T staging of rectal cancer can be accurately performedby a transrectal endoscopic ultrasound (EUS). Several past studies confirmed itssuperiority over CT scan. Unfortunately, current oblique endoscopic viewingradial-array EUS has a limitation of endoscopic view and precludes deepintubation of EUS probe into colon beyond rectum. With a newly designedforward-viewing radial-array echoendoscope (radial Scan Ultrasonic VideoEndoscope EG-530UR2 (FUJIFILM Corporation, Tokyo, Japan) and Ultrasound

Figure 1. Surgical Pathology Results for 34 Patients with EUS Diagnosisof T2N0 Rectal Cancer

Abstracts

AB368 GASTROINTESTINAL ENDOSCOPY Volume 77, No. 5S : 2013 www.giejournal.org