title: An evaluation of a superfast MRI sequence in the diagnosis of suspected acute appendicitis.
abstract: BACKGROUND
  A lack of typical symptoms in acute appendicitis may delay the appropriate therapy. We hypothesized that a superfast MRI sequence with fat suppression could assist in the diagnosis of acute appendicitis.
  
  
  OBJECTIVE
  To evaluate the sensitivity and specificity of MRI in the diagnosis of suspected acute appendicitis especially in the early stages and before surgery.
  
  
  METHODS
  Subject images were acquired with a 1.5-T clinical MRI scanner (Achieva Nova Dual, Philips, Netherlands) with a four-element phased array abdominal coil with a SENSE factor of 1.8. A total of 41 cases with suspected acute appendicitis were recruited. SENSE-BTFE-SPIR sequence, sensitivity encoding (SENSE) with balanced turbo field echo (BTFE) and spectral presaturation and inversion recovery (SPIR), was adopted in this study.
  
  
  RESULTS
  The sensitivity and specificity were 91.7% and 100%, respectively, in the diagnosis of acute appendicitis by SENSE-BTFE-SPIR in this series. Cases with simple acute appendicitis showed a higher T2 signal in the appendiceal wall, with local fluid surrounding appendix. Cases with purulent appendicitis showed an increased T2 signal within the cavity of the appendix, along with appendiceal wall thickening, or increased T2 signals around effusions in cases with gangrenous appendicitis. A periappendiceal abscess showed a localized, high-signal fluid collection that may have had extensive effects on the adjacent bowel loops, into which the entire appendix may disappear.
  
  
  CONCLUSIONS
  The fast SENSE-BTFE-SPIR sequence is capable of demonstrating the location and position of the appendix, the presence of acute appendicitis and its complications, and the clinical stages.
authors.affiliation: Department of Radiology, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, P. R. China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhu
authors.forename: Bing
authors.initials: B
authors.lastname: Zhang
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Shifu
authors.initials: S
authors.lastname: Xi
authors.forename: Decai
authors.initials: D
authors.lastname: Yu
authors.forename: Yitao
authors.initials: Y
authors.lastname: Ding
keywords: Acute appendicitis; magnetic resonance imaging; superfast sequence