title: Noninvasive ureterocele puncture using pulsed focused ultrasound: an in vitro study.
abstract: OBJECTIVE
  To evaluate the feasibility of performing noninvasive puncture of pediatric ureteroceles with cavitation-based focused ultrasound (US) (histotripsy).
  
  
  METHODS
  A model for the ureterocele wall was developed from an excised bovine bladder wall. The model was exposed to focused US pulses in a water bath under three different US parameter sets for up to 300 seconds to create localized perforations in the wall. B-mode US imaging was used to monitor the treatment and assess potential imaging guidance and feedback.
  
  
  RESULTS
  Punctures were formed between 46-300 seconds, depending on the focused US exposure parameters and model wall thickness. Puncture diameter was controllable through choice of exposure parameters and could be varied between 0.8-2.8 mm mean diameter. US-induced cavitation was visible on B-mode imaging, which provided targeting and treatment feedback.
  
  
  CONCLUSIONS
  Cavitation-based focused US can create punctures in a model that mimics the tissue properties of a ureterocele wall, under guidance from US imaging.
authors.affiliation: 1 Department of Urology, University of Washington School of Medicine , Seattle, Washington.
authors.forename: Adam D
authors.initials: AD
authors.lastname: Maxwell
authors.forename: Ryan S
authors.initials: RS
authors.lastname: Hsi
authors.forename: Michael R
authors.initials: MR
authors.lastname: Bailey
authors.forename: Pasquale
authors.initials: P
authors.lastname: Casale
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Lendvay
mesh_terms: D000818:Animals; D002417:Cattle; D004195:Disease Models, Animal; D004867:Equipment Design; D057086:High-Intensity Focused Ultrasound Ablation / Q000295:instrumentation*; D011677:Punctures / Q000379:methods; D014518:Ureterocele / Q000601:surgery*; D001743:Urinary Bladder / Q000601:surgery*