title: Magnetic resonance imaging in pediatric appendicitis: a systematic review.
abstract: Magnetic resonance imaging for the evaluation of appendicitis in children has rapidly increased recently. This change has been primarily driven by the desire to avoid CT radiation dose. This meta-analysis reviews the diagnostic performance of MRI for pediatric appendicitis and discusses current knowledge of cost-effectiveness. We used a conservative Haldane correction statistical method and found pooled diagnostic parameters including a sensitivity of 96.5% (95% confidence interval [CI]: 94.3-97.8%), specificity of 96.1% (95% CI: 93.5-97.7%), positive predictive value of 92.0% (95% CI: 89.3-94.0%) and negative predictive value of 98.3% (95% CI: 97.3-99.0%), based on 11 studies. Assessment of patient outcomes associated with MRI use at two institutions indicates that time to antibiotics was 4.7 h and 8.2 h, time to appendectomy was 9.1 h and 13.9 h, and negative appendectomy rate was 3.1% and 1.4%, respectively. Alternative diagnoses were present in ~20% of cases, most commonly adnexal cysts and enteritis/colitis. Regarding technique, half-acquisition single-shot fast spin-echo (SSFSE) pulse sequences are crucial. While gadolinium-enhanced T1-weighted pulse sequences might be helpful, any benefit beyond non-contrast MRI has not been confirmed. Balanced steady-state free precession (SSFP) sequences are generally noncontributory. Protocols do not need to exceed five sequences; four-sequence protocols are commonly utilized. Sedation generally is not indicated; patients younger than 5 years might be attempted based on the child's ability to cooperate. A comprehensive pediatric cost-effectiveness analysis that includes both direct and indirect costs is needed.
authors.affiliation: Department of Radiology, Penn State Hershey Children's Hospital, The Pennsylvania State University College of Medicine, 500 University Drive, H066, P.O. Box 850, Hershey, PA, 17033-0850, USA. mmoore5@hmc.psu.edu.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Moore
authors.affiliation: Department of Surgery, The Pennsylvania State University College of Medicine, Hershey, PA, USA.
authors.forename: Afif N
authors.initials: AN
authors.lastname: Kulaylat
authors.affiliation: Department of Surgery, The Pennsylvania State University College of Medicine, Hershey, PA, USA.|Department of Public Health Sciences, The Pennsylvania State University College of Medicine, Hershey, PA, USA.
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Hollenbeak
authors.affiliation: Department of Surgery, The Pennsylvania State University College of Medicine, Hershey, PA, USA.
authors.forename: Brett W
authors.initials: BW
authors.lastname: Engbrecht
authors.affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Dillman
authors.affiliation: Department of Radiology, Penn State Hershey Children's Hospital, The Pennsylvania State University College of Medicine, 500 University Drive, H066, P.O. Box 850, Hershey, PA, 17033-0850, USA.
authors.forename: Sosamma T
authors.initials: ST
authors.lastname: Methratta
mesh_terms: D001064:Appendicitis / Q000000981:diagnostic imaging*; D001065:Appendix / Q000000981:diagnostic imaging; D002648:Child; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*
keywords: Appendicitis; Appendix; Children; Magnetic resonance imaging; Meta-analysis