title: Apparent migration of implantable port devices: normal variations in consideration of BMI.
abstract: OBJECTIVE
  To evaluate the extent of normal variation in implantable port devices between supine fluoroscopy and upright chest x-ray in relation to body mass index (BMI) based on three different measurement methods.
  
  
  METHODS
  Retrospectively, 80 patients with implanted central venous access port systems from 2012-01-01 until 2013-12-31 were analyzed. Three parameters (two quantitative and one semi-quantitative) were determined to assess port positions: projection of port capsule to anterior ribs (PCP) and intercostal spaces, ratio of extra- and intravascular catheter portions (EX/IV), normalized distance of catheter tip to carina (nCTCD). Changes were analyzed for males and females and normal-weight and overweight patients using analysis of variance with Bonferroni-corrected pairwise comparison.
  
  
  RESULTS
  PCP revealed significantly greater changes in chest x-rays in overweight women than in the other groups (p&lt;0.001, F-test). EX/IV showed a significantly higher increase in overweight women than normal-weight women and men and overweight men (p&lt;0.001). nCTCD showed a significantly greater increase in overweight women than overweight men (p = 0.0130). There were no significant differences between the other groups. Inter- and intra-observer reproducibility was high (Cronbach alpha of 0.923-1.0) and best for EX/IV.
  
  
  CONCLUSIONS
  Central venous port systems show wide normal variations in the projection of catheter tip and port capsule. In overweight women apparent catheter migration is significantly greater compared with normal-weight women and with men. The measurement of EX/IV and PCP are straightforward methods, quick to perform, and show higher reproducibility than measurement of catheter tip-to-carina distance.
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin - Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Wyschkon
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin - Germany.
authors.forename: Jan-Phillip
authors.initials: JP
authors.lastname: Löschmann
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin - Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Scheurig-Münkler
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin - Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Nagel
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin - Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Hamm
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin - Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Elgeti
mesh_terms: D059925:Anatomic Landmarks; D015992:Body Mass Index; D002405:Catheterization, Central Venous / Q000009:adverse effects / Q000295:instrumentation*; D002408:Catheters, Indwelling; D062905:Central Venous Catheters; D004867:Equipment Design; D005260:Female; D005471:Fluoroscopy; D005548:Foreign-Body Migration / Q000000981:diagnostic imaging / Q000209:etiology*; D006801:Humans; D008297:Male; D009765:Obesity / Q000150:complications* / Q000175:diagnosis; D056888:Patient Positioning; D011237:Predictive Value of Tests; D013902:Radiography, Thoracic; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D016683:Supine Position