title: MRI usage in a pediatric emergency department: an analysis of usage and usage trends over 5 years.
abstract: BACKGROUND
  Magnetic resonance imaging (MRI) usage has anecdotally increased due to the principles of ALARA and the desire to Image Gently. Aside from a single abstract in the emergency medicine literature, pediatric emergency department MRI usage has not been described.
  
  
  OBJECTIVE
  Our objective was to determine whether MRI use is indeed increasing at a high-volume urban pediatric emergency department with 24/7 MRI availability. Also, we sought to determine which exams, time periods and demographics influenced the trend.
  
  
  METHODS
  Institutional Review Board exemption was obtained. Emergency department patient visit and exam data were obtained from the hospital database for the 2011-2015 time period. MRI usage data were normalized using emergency department patient visit data to determine usage rates. The z-test was used to compare MRI use by gender. The chi-square test was used to test for trends in MRI usage during the study period and in patient age. MRI usage for each hour and each weekday were tabulated to determine peak and trough usage times.
  
  
  RESULTS
  MRI usage rate per emergency department patient visit was 0.36%. Headache, pain and rule-out appendicitis were the most common indications for neuroradiology, musculoskeletal and trunk exams, respectively. Usage in female patients was significantly greater than in males (0.42% vs. 0.29%, respectively, P<0.001). Usage significantly increased during the 5-year period (P<0.001). Use significantly increased from age 3 to 17 (0.011% to 1.1%, respectively, P<0.001). Sixty percent of exams were performed after-hours, the highest volume during the 10 p.m. hour and lowest between 4 a.m. and 9 a.m. MRI use was highest on Thursdays and lowest on Sundays (MRI on 0.45% and 0.22% of patients, respectively).
  
  
  CONCLUSIONS
  MRI use in children increased during the study period, most notably in females, on weekdays and after-hours.
authors.affiliation: Department of Radiology, Division of Emergency Radiology, Montefiore Medical Center, Albert Einstein College of Medicine, 111 E. 210 Street, Bronx, NY, 10467, USA. mscheinf@montefiore.org.
authors.forename: Meir H
authors.identifier: http://orcid.org/0000-0001-8880-4318
authors.initials: MH
authors.lastname: Scheinfeld
authors.affiliation: Department of Epidemiology & Population Health, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Jee-Young
authors.initials: JY
authors.lastname: Moon
authors.affiliation: Department of Pediatrics, Division of Emergency Medicine, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Michele J
authors.initials: MJ
authors.lastname: Fagan
authors.affiliation: Department of Radiology, Montefiore Medical Center, Bronx, NY, USA.
authors.forename: Reubin
authors.initials: R
authors.lastname: Davoudzadeh
authors.affiliation: Department of Epidemiology & Population Health, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.affiliation: Department of Radiology, Division of Pediatric Radiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Taragin
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006776:Hospitals, Pediatric / Q000706:statistics & numerical data*; D006786:Hospitals, Urban / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data*; D008297:Male; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D014600:Utilization Review
keywords: Children; Clinical indication; Emergency department; Magnetic resonance imaging; Utilization