title: A randomised experiment comparing low-cost ultrasound gel alternative with commercial gel.
abstract: OBJECTIVE
  Point-of-care ultrasound is a portable, relatively low-cost imaging modality with great potential utility in low-resource settings. However, commercially produced ultrasound gel is often cost-prohibitive and unavailable. We investigated whether images obtained using an alternative cornstarch-based gel would be of comparable quality with those using commercial gel.
  
  
  METHODS
  This was a blinded, randomised, cross-over study comparing commercially produced ultrasound gel with home-made cornstarch-based gel. Ultrasound-trained faculty obtained three video clips with each gel type from patients at one urban ED. The clips were evaluated by a radiologist and an ultrasound-trained emergency physician. Images were assessed in terms of overall adequacy (dichotomous) and quality, resolution and detail using a rating scale (0-10). All sonographers and physicians reviewing the images were blinded to the type of gel used.
  
  
  RESULTS
  Thirty-four patients were enrolled in the study, producing 204 separate images (102 with each gel). The cornstarch gel clips were deemed accurate in 70.6% (95% CI 63.9% to 76.5%) of the scans, as compared with 65.2% (95% CI 58.4% to 71.4%) of those using commercial gel. There was no difference between the two groups with respect to image detail, resolution or quality.
  
  
  CONCLUSIONS
  Images produced using the cornstarch-based alternative ultrasound gel were of similar quality to those using commercial gel. The low cost and easy preparation of the cornstarch-based gel make it an attractive coupling medium for use in low-resource settings.
authors.affiliation: Department of Emergency Medicine, Alameda Health System-Highland Hospital, Oakland, California, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Riguzzi
authors.affiliation: Department of Emergency Medicine, Alameda Health System-Highland Hospital, Oakland, California, USA.
authors.forename: Allison
authors.initials: A
authors.lastname: Binkowski
authors.affiliation: Department of Emergency Medicine, Tampa General Hospital, Tampa, Florida, USA.
authors.forename: Mike
authors.initials: M
authors.lastname: Butterfield
authors.affiliation: Department of Radiology, Alameda Health System-Highland Hospital, Oakland, California, USA.
authors.forename: Farhad
authors.initials: F
authors.lastname: Sani
authors.affiliation: Department of Emergency Medicine, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Nathan
authors.initials: N
authors.lastname: Teismann
authors.affiliation: Department of Emergency Medicine, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Jahan
authors.initials: J
authors.lastname: Fahimi
mesh_terms: D000328:Adult; D002140:California; D018592:Cross-Over Studies; D004636:Emergency Service, Hospital / Q000191:economics / Q000458:organization & administration; D005260:Female; D005782:Gels / Q000008:administration & dosage / Q000592:standards*; D006801:Humans; D008297:Male; D008875:Middle Aged; D000067716:Point-of-Care Testing / Q000191:economics / Q000592:standards; D013213:Starch / Q000494:pharmacology / Q000627:therapeutic use; D014463:Ultrasonography / Q000191:economics* / Q000379:methods*
chemical_list: D005782:Gels; D013213:Starch
keywords: global health; ultrasound