title: Referenceless acquisition of phase-sensitive inversion-recovery with decisive reconstruction (RAPID) imaging.
abstract: OBJECTIVE
  To describe a referenceless reconstruction approach to generate phase-sensitive inversion recovery images without relying on the extra acquisition of reference images.
  
  
  METHODS
  The basic idea of the Referenceless Acquisition of Phase-sensitive Inversion-recovery with Decisive reconstruction, or RAPID, algorithm is to retrieve the magnetization polarity by estimating the background phase variation of a complex valued image. The theory and algorithm of RAPID is described in detail. To evaluate the performance of RAPID, seven patients were recruited then scanned in different anatomical regions (cardiac, brain, and vascular). Standard Phase Sensitive Inversion Recovery (PSIR) reconstructions using reference image information were compared with RAPID reconstructions using the same source data.
  
  
  RESULTS
  RAPID reconstructed images were found to provide very good agreement with PSIR reconstructed images on all cases, although no reference image info was used in the RAPID algorithm. For neuroimaging applications, it was found that RAPID reconstruction is more robust compared with the PSIR algorithm as RAPID can avoid potential errors introduced by the reference acquisition.
  
  
  CONCLUSIONS
  The RAPID technique for phase-sensitive reconstruction is promising and can improve the imaging efficiency by a factor of 2 compared with PSIR. RAPID was also shown to provide more robust reconstruction by avoiding errors caused by the reference acquisition.
authors.affiliation: Clinical Sites Research Program, Philips Research North America, Briarcliff Manor, New York, USA.
authors.forename: Jinnan
authors.initials: J
authors.lastname: Wang
authors.forename: Huijun
authors.initials: H
authors.lastname: Chen
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Maki
authors.forename: Xihai
authors.initials: X
authors.lastname: Zhao
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Wilson
authors.forename: Chun
authors.initials: C
authors.lastname: Yuan
authors.forename: Peter
authors.initials: P
authors.lastname: Börnert
mesh_terms: D000465:Algorithms; D002340:Carotid Artery Diseases / Q000175:diagnosis; D002561:Cerebrovascular Disorders / Q000175:diagnosis; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009203:Myocardial Infarction / Q000473:pathology; D019047:Phantoms, Imaging
keywords: PSIR; RAPID; phase-sensitive; reconstruction