title: Wireless capsules for esophageal pH monitoring: are we placing them correctly?
abstract: BACKGROUND
  Recommended Bravo capsule placement is 6 cm proximal to the squamocolumnar junction. This is because the junction resides 1 cm distal to the lower esophageal sphincter.
  
  
  OBJECTIVE
  To determine the positional accuracy of capsule placement compared with the ideal location in symptomatic patients.
  
  
  METHODS
  Retrospective analysis of consecutive symptomatic outpatients undergoing both capsule placement and esophageal manometry on the same day. Error in capsule placement (ECP) was calculated as the actual capsule position (ACP) minus the ideal capsule position (ICP) based on manometry results. An error in positioning < or =3 cm was deemed an accurate placement.
  
  
  RESULTS
  Accurate placement of the capsule occurred in 91/147 (62%) patients. In patients with inaccurate placement, 92.9% were placed >3 cm proximal to the ICP. Only longer esophageal length correlated with the severity of proximal misplacement. There was no relationship between severity of ECP and whether the study demonstrated acid reflux.
  
  
  CONCLUSIONS
  Our results suggest that endoscopic misplacement of Bravo capsules is common. Capsule misplacement proximally occurred far more frequently than distal misplacement. Capsule misplacement was not associated with pH study results.
authors.affiliation: Gastroenterology Section, Temple University School of Medicine, Philadelphia, PA 19140, USA.
authors.forename: Siva
authors.initials: S
authors.lastname: Doma
authors.forename: Susmita
authors.initials: S
authors.lastname: Paladugu
authors.forename: Henry P
authors.initials: HP
authors.lastname: Parkman
authors.forename: Frank K
authors.initials: FK
authors.lastname: Friedenberg
mesh_terms: D000704:Analysis of Variance; D053704:Capsule Endoscopy; D016009:Chi-Square Distribution; D050782:Esophageal pH Monitoring / Q000295:instrumentation*; D004947:Esophagus / Q000033:anatomy & histology*; D005260:Female; D005764:Gastroesophageal Reflux / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008365:Manometry; D019300:Medical Errors / Q000706:statistics & numerical data*; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D012189:Retrospective Studies