title: Use of the front-view forward-array echoendoscope to evaluate right colonic subepithelial lesions.
abstract: BACKGROUND
  Endosonographic evaluation and sampling of right colonic subepithelial lesions is technically difficult.
  
  
  OBJECTIVE
  To evaluate the feasibility, safety, and tissue yield of a prototype front-view, forward-array, curved linear array echoendoscope in the evaluation and sampling of right colonic subepithelial lesions.
  
  
  METHODS
  Tertiary referral center.
  
  
  METHODS
  Procedural and outcome data on all patients undergoing EUS evaluation of right-sided colonic and pericolonic lesions were collected during a 1-year study period.
  
  
  METHODS
  Patient demographics, clinical indication, EUS findings, EUS-FNA yield, technical success, and procedural complications.
  
  
  RESULTS
  A total of 15 patients underwent EUS examination of right-sided colonic lesions with the prototype echoendoscope. The lesions were located in the cecum (n = 12) and the ascending colon (n = 3). The cecum was reached in all examinations within 10 minutes. Twelve patients had subepithelial lesions detected during colonoscopy. Findings included 6 extrinsic compressions from an adjacent normal structure, 1 calcified lymph node, 1 ovarian cyst, 1 prolapsed appendiceal orifice, 1 GI stromal tumor, 1 appendiceal mucocele, and 1 lymphoma. Two patients were evaluated for a pericolonic lesion seen on CT; findings included focal diverticulitis and a metastatic lymph node. In the patient evaluated for an infiltrative mass with previous nondiagnostic biopsies, colonic histoplasmosis was diagnosed. FNA was performed in 6 patients and provided diagnostic samples in 5 (83%). No procedure- or FNA-related complications were reported.
  
  
  CONCLUSIONS
  Endosonographic evaluation and sampling of right-sided colonic subepithelial lesions with the prototype front-view, forward-array, curved linear array echoendoscope is feasible and safe. The yield of FNA is high, consistent with applications in the upper GI tract.
authors.affiliation: Interventional Endoscopy Services, California Pacific Medical Center, San Francisco, California 94115, USA.
authors.forename: Thai
authors.initials: T
authors.lastname: Nguyen-Tang
authors.forename: Janak N
authors.initials: JN
authors.lastname: Shah
authors.forename: Andres
authors.initials: A
authors.lastname: Sanchez-Yague
authors.forename: Kenneth F
authors.initials: KF
authors.lastname: Binmoeller
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle / Q000295:instrumentation; D002430:Cecal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D044682:Colon, Ascending; D003108:Colonic Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D003111:Colonic Polyps / Q000000981:diagnostic imaging* / Q000473:pathology; D020685:Colonoscopes; D003937:Diagnosis, Differential; D019160:Endosonography / Q000295:instrumentation*; D004867:Equipment Design; D004869:Equipment Safety; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000000981:diagnostic imaging / Q000473:pathology; D007415:Intestinal Obstruction / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D018084:Ultrasonography, Interventional / Q000295:instrumentation*