title: Computed tomography localization of the appendix in the pediatric population relative to the lumbar spine.
abstract: BACKGROUND
  Computed tomography (CT) is commonly used to evaluate suspected acute appendicitis. Although very effective, CT uses ionizing radiation, exposing patients to an increased risk of cancer.
  
  
  OBJECTIVE
  This study assessed the potential for decreasing the field of view of the CT (and therefore the dose to the patient) in the evaluation of suspected acute appendicitis in children.
  
  
  METHODS
  This study was a retrospective review of prospectively collected data from 212 consecutive patients who underwent CT for suspected acute appendicitis. The most superior aspect of the appendix with respect to vertebral bodies was recorded. Age, gender and diagnosis (negative, acute appendicitis or alternative diagnosis) were noted.
  
  
  RESULTS
  The appendix was visualized in 190 of 212 subjects (89.6%). Overall, all visualized appendixes were located at or below the level of L1. Sixty-three of the subjects (29.7%) were diagnosed with acute appendicitis via CT imaging. All appendixes in patients with acute appendicitis were located at or below the level of the L3 vertebral body, predominating at the level of L5. Six subjects (3.1%) received alternative diagnoses, including pneumonia, pyelonephritis, small bowel obstruction and infected urachal cyst. There were no differences in appendix location with regard to diagnosis, gender, or age (P=0.664, 0.748 and 0.705, respectively).
  
  
  CONCLUSIONS
  CT field of view may be decreased to the level of L1 or L3 superiorly, decreasing radiation dose without affecting the rate of appendix visualization.
authors.affiliation: Maricopa Medical Center Department of Surgery, Maricopa Integrated Health System, 2601 E. Roosevelt St., Phoenix, AZ, 85008, USA. john.davis@mihs.org.
authors.forename: John
authors.initials: J
authors.lastname: Davis
authors.affiliation: Maricopa Medical Center Department of Radiology, Maricopa Integrated Health System, Phoenix, AZ, USA.
authors.forename: Albert T
authors.initials: AT
authors.lastname: Roh
authors.affiliation: University of Arizona College of Medicine, Phoenix, AZ, USA.
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Petterson
authors.affiliation: Maricopa Medical Center Department of Surgery, Maricopa Integrated Health System, 2601 E. Roosevelt St., Phoenix, AZ, 85008, USA.
authors.forename: Tammy R
authors.initials: TR
authors.lastname: Kopelman
authors.affiliation: Maricopa Medical Center Department of Radiology, Maricopa Integrated Health System, Phoenix, AZ, USA.
authors.forename: Samantha L
authors.initials: SL
authors.lastname: Matz
authors.affiliation: Maricopa Medical Center Department of Radiology, Maricopa Integrated Health System, Phoenix, AZ, USA.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Gridley
authors.affiliation: Maricopa Medical Center Department of Radiology, Maricopa Integrated Health System, Phoenix, AZ, USA.
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Connell
mesh_terms: D000293:Adolescent; D059925:Anatomic Landmarks; D001064:Appendicitis / Q000000981:diagnostic imaging*; D001065:Appendix / Q000033:anatomy & histology*; D002648:Child; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007479:Iopamidol; D008159:Lumbar Vertebrae / Q000033:anatomy & histology*; D008297:Male; D000069079:Radiation Exposure; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007479:Iopamidol
keywords: Acute appendicitis; Appendix; Children; Computed tomography; Radiation