title: Development of an in-house endoanal ultrasound teaching phantom.
abstract: OBJECTIVE
  The aim of this study was to construct an anatomically correct phantom for visualization of anal sphincter complex structures.
  
  
  METHODS
  To ake an endoanal ultrasound phantom, we experimented with a variety of commercially available materials to simulate hyperechoic, hypoechoic, and isoechoic tissue consistency. We created external anal sphincter muscle and the levator plate using stand-alone density gel and microbubbles to simulate the echogenicity of the muscles. A mold was created in a container, the muscles were inserted, and the mold was filled with high-density clear gel and allowed to fill. Once finished, the container was sealed tightly and stored for later use. To evaluate the accuracy of the model, 6 ultrasound imaging raters from different disciplines were included. The raters were administered a 6-item Internet-based interactive test using 2-dimensional images obtained from scanning the phantom. Rater agreement was determined. The Fleiss κstatistic was calculated to determine inter-rater reliability.
  
  
  RESULTS
  The raters identified the structures in 32 (89%) of 36 test questions. There was good to excellent agreement among the readers. Agreement rates for visualization of the external anal sphincter, perineal body, and internal anal sphincter were 67%, 83%, and 100%, respectively.
  
  
  CONCLUSIONS
  An endoanal phantom can be constructed as a simulator for endoanal sonography.
authors.affiliation: Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190, USA. abbas-shobeiri@ouhsc.edu
authors.forename: S Abbas
authors.initials: SA
authors.lastname: Shobeiri
authors.forename: Ghazaleh
authors.initials: G
authors.lastname: Rostaminia
authors.forename: Hediyeh
authors.initials: H
authors.lastname: Shobeiri
mesh_terms: D001003:Anal Canal / Q000000981:diagnostic imaging*; D032701:Biomimetics / Q000295:instrumentation*; D019160:Endosonography / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D009825:Oklahoma; D019047:Phantoms, Imaging; D011871:Radiology / Q000193:education*
keywords: anal sphincter; endoanal ultrasound; phantom