title: Software-assisted small bowel motility analysis using free-breathing MRI: feasibility study.
abstract: OBJECTIVE
  To validate a software prototype allowing for small bowel motility analysis in free breathing by comparing it to manual measurements.
  
  
  METHODS
  In all, 25 patients (15 male, 10 female; mean age 39 years) were included in this Institutional Review Board-approved, retrospective study. Magnetic resonance imaging (MRI) was performed on a 1.5T system after standardized preparation acquiring motility sequences in free breathing over 69-84 seconds. Small bowel motility was analyzed manually and with the software. Functional parameters, measurement time, and reproducibility were compared using the coefficient of variance and paired Student's t-test. Correlation was analyzed using Pearson's correlation coefficient and linear regression.
  
  
  RESULTS
  The 25 segments were analyzed twice both by hand and using the software with automatic breathing correction. All assessed parameters significantly correlated between the methods (P < 0.01), but the scattering of repeated measurements was significantly (P < 0.01) lower using the software (3.90%, standard deviation [SD] ± 5.69) than manual examinations (9.77%, SD ± 11.08). The time needed was significantly less (P < 0.001) with the software (4.52 minutes, SD ± 1.58) compared to manual measurement, lasting 17.48 minutes for manual (SD ± 1.75 minutes).
  
  
  CONCLUSIONS
  The use of the software proves reliable and faster small bowel motility measurements in free-breathing MRI compared to manual analyses. The new technique allows for analyses of prolonged sequences acquired in free breathing, improving the informative value of the examinations by amplifying the evaluable data.
authors.affiliation: University Hospital Zürich, Department of Radiology, Zürich, Switzerland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bickelhaupt
authors.forename: Johannes M
authors.initials: JM
authors.lastname: Froehlich
authors.forename: Roger
authors.initials: R
authors.lastname: Cattin
authors.forename: Stephan
authors.initials: S
authors.lastname: Raible
authors.forename: Hanspeter
authors.initials: H
authors.lastname: Bouquet
authors.forename: Urs
authors.initials: U
authors.lastname: Bill
authors.forename: Michael A
authors.initials: MA
authors.lastname: Patak
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005240:Feasibility Studies; D005260:Female; D005769:Gastrointestinal Motility / Q000502:physiology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012119:Respiration; D012189:Retrospective Studies; D012984:Software; D055815:Young Adult
keywords: free-breathing MRI; motility assessment; small bowel; small bowel motility; software-assisted