title: Computerized Diagnostic Assistant for the Automatic Detection of Pneumothorax on Ultrasound: A Pilot Study.
abstract: BACKGROUND
  Bedside thoracic ultrasound (US) can rapidly diagnose pneumothorax (PTX) with improved accuracy over the physical examination and without the need for chest radiography (CXR); however, US is highly operator dependent. A computerized diagnostic assistant was developed by the United States Army Institute of Surgical Research to detect PTX on standard thoracic US images. This computer algorithm is designed to automatically detect sonographic signs of PTX by systematically analyzing B-mode US video clips for pleural sliding and M-mode still images for the seashore sign. This was a pilot study to estimate the diagnostic accuracy of the PTX detection computer algorithm when compared to an expert panel of US trained physicians.
  
  
  METHODS
  This was a retrospective study using archived thoracic US obtained on adult patients presenting to the emergency department (ED) between 5/23/2011 and 8/6/2014. Emergency medicine residents, fellows, attending physicians, physician assistants, and medical students performed the US examinations and stored the images in the picture archive and communications system (PACS). The PACS was queried for all ED bedside US examinations with reported positive PTX during the study period along with a random sample of negatives. The computer algorithm then interpreted the images, and we compared the results to an independent, blinded expert panel of three physicians, each with experience reviewing over 10,000 US examinations.
  
  
  RESULTS
  Query of the PACS system revealed 146 bedside thoracic US examinations for analysis. Thirteen examinations were indeterminate and were excluded. There were 79 true negatives, 33 true positives, 9 false negatives, and 12 false positives. The test characteristics of the algorithm when compared to the expert panel were sensitivity 79% (95 % CI [63-89]) and specificity 87% (95% CI [77-93]). For the 20 images scored as highest quality by the expert panel, the algorithm demonstrated 100% sensitivity (95% CI [56-100]) and 92% specificity (95% CI [62-100]).
  
  
  CONCLUSIONS
  This novel computer algorithm has potential to aid clinicians with the identification of the sonographic signs of PTX in the absence of expert physician sonographers. Further refinement and training of the algorithm is still needed, along with prospective validation, before it can be utilized in clinical practice.
authors.affiliation: Brooke Army Medical Center, Department of Emergency Medicine, San Antonio, Texas.
authors.forename: Shane M
authors.initials: SM
authors.lastname: Summers
authors.affiliation: Brooke Army Medical Center, Department of Emergency Medicine, San Antonio, Texas.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Chin
authors.affiliation: Brooke Army Medical Center, Department of Emergency Medicine, San Antonio, Texas.
authors.forename: Brit J
authors.initials: BJ
authors.lastname: Long
authors.affiliation: United States Army Institute of Surgical Research, San Antonio, Texas.
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Grisell
authors.affiliation: Brooke Army Medical Center, Department of Emergency Medicine, San Antonio, Texas.
authors.forename: John G
authors.initials: JG
authors.lastname: Knight
authors.affiliation: Brooke Army Medical Center, Department of Pulmonary/Critical Care, San Antonio, Texas.
authors.forename: Kurt W
authors.initials: KW
authors.lastname: Grathwohl
authors.affiliation: Brooke Army Medical Center, Department of Radiology, San Antonio, Texas.
authors.forename: John L
authors.initials: JL
authors.lastname: Ritter
authors.affiliation: Brooke Army Medical Center, Department of Emergency Medicine, San Antonio, Texas.
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Morgan
authors.affiliation: United States Army Institute of Surgical Research, San Antonio, Texas.
authors.forename: Jose
authors.initials: J
authors.lastname: Salinas
authors.affiliation: United States Army Medical Department Center and School.
authors.forename: Lorne H
authors.initials: LH
authors.lastname: Blackbourne
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002140:California; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004636:Emergency Service, Hospital; D006801:Humans; D008875:Middle Aged; D010865:Pilot Projects; D011030:Pneumothorax / Q000000981:diagnostic imaging*; D019095:Point-of-Care Systems; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014463:Ultrasonography; D055815:Young Adult