title: Benefit of pronase in image quality during EUS.
abstract: BACKGROUND
  EUS is useful for diagnosis of GI disease. However, artifacts caused by gastric mucus may worsen visibility during EUS.
  
  
  OBJECTIVE
  To investigate the efficacy of premedication with pronase, the proteolytic enzyme, for improving imaging during EUS.
  
  
  METHODS
  Blinded, randomized, prospective study.
  
  
  METHODS
  Tertiary-care referral center.
  
  
  METHODS
  This study involved 183 patients scheduled for EUS.
  
  
  METHODS
  Patients were assigned to oral premedication with saline solution (group A), pronase and bicarbonate (group B), or pronase, bicarbonate, and simethicone (group C). Either conventional EUS or high-frequency catheter EUS (HFUS) was selected. Gastric cavity and gastric mucosal surface obscurity grades were assessed by using visibility scores from ultrasonographic images of each patient.
  
  
  METHODS
  Means of visibility scores and proportion of images with better visibility scores of the gastric cavity and gastric mucosal surface. Lower scores indicate better visibility of the gastric mucosal surface and fewer artifacts within the gastric cavity on conventional EUS and HFUS.
  
  
  RESULTS
  Group B had significantly lower mean gastric cavity and gastric mucosal surface visibility scores than did groups A and C in both conventional EUS and HFUS. Group B also had a high proportion of images that had better gastric cavity and gastric mucosal surface visibility scores than did the other two groups in conventional EUS and HFUS.
  
  
  CONCLUSIONS
  Small number of patients and no assessment of the amount of mucus before oral premedication.
  
  
  CONCLUSIONS
  Premedication for conventional EUS and HFUS by using a mixture of pronase and bicarbonate seems to decrease the number of gastric wall and lumen hyperechoic artifacts observed in patients given either saline solution or pronase/bicarbonate/simethicone.
authors.affiliation: Digestive Disease Center, Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon, Korea.
authors.forename: Jae Pil
authors.initials: JP
authors.lastname: Han
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Hong
authors.forename: Jong Ho
authors.initials: JH
authors.lastname: Moon
authors.forename: Gun Hwa
authors.initials: GH
authors.lastname: Lee
authors.forename: Jin Myung
authors.initials: JM
authors.lastname: Byun
authors.forename: Hwa Jong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Hyun Jong
authors.initials: HJ
authors.lastname: Choi
authors.forename: Bong Min
authors.initials: BM
authors.lastname: Ko
authors.forename: Moon Sung
authors.initials: MS
authors.lastname: Lee
mesh_terms: D000284:Administration, Oral; D016477:Artifacts; D004066:Digestive System Diseases / Q000000981:diagnostic imaging*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D019160:Endosonography / Q000592:standards*; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008297:Male; D008875:Middle Aged; D011292:Premedication / Q000379:methods*; D011402:Pronase / Q000008:administration & dosage*; D015203:Reproducibility of Results
chemical_list: D011402:Pronase