title: Methods to reduce patients' maximum skin dose during percutaneous coronary intervention for chronic total occlusion.
abstract: OBJECTIVE
  The purpose of this research is to assess the patient's entrance skin dose (ESD) during percutaneous coronary intervention (PCI) for chronic total occlusion (CTO), and discuss methods to reduce the maximum ESDs.
  
  
  BACKGROUND
  Only a few reports are available on the methods to reduce patients' maximum ESD during the procedures.
  
  
  METHODS
  This study included consecutive 30 patients who underwent PCI procedures for CTO in the three institutions. Pearson correlation test was employed to determine the relationship between total fluoroscopic time (TFT) and the maximum ESD, dose area product (DAP) value, and the maximum ESD in each institution.
  
  
  RESULTS
  There were significant correlations between the TFT and maximum ESD (Institution 1: P = 0.000410, Institution 2: P = 0.000525), and between the DAP and the maximum ESD (Institution 2: P < 0.0001). In Institution 1, TFT of 60 min was set as the upper limit, and the maximum ESDs were controlled within 7 Gy. In Institution 2, the angiographic unit was a biplane system, and two skin sites were exposed, corresponding to the angulation of each X-ray tube. In Institution 3, the interventionalist changed the beam angulations frequently by several degrees during the procedures, and the maximum ESD was controlled within 3 Gy even during procedures with a TFT of more than 1 hr.
  
  
  CONCLUSIONS
  The TFT and DAP, the latter of which is preferable, are useful to estimate the maximum ESD. Limiting the TFT or DAP, or changing the beam angulations is important to control ESD during prolonged procedures.
authors.affiliation: Department of Radiology, Teikyo University School of Medicine, Kaga, Itabashi-ku, Tokyo, Japan. s-suzuki@med.teikyo-u.ac.jp
authors.forename: Shigeru
authors.initials: S
authors.lastname: Suzuki
authors.forename: Shigeru
authors.initials: S
authors.lastname: Furui
authors.forename: Takaaki
authors.initials: T
authors.lastname: Isshiki
authors.forename: Ken
authors.initials: K
authors.lastname: Kozuma
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Koyama
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ochiai
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Asakura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary; D002908:Chronic Disease; D017023:Coronary Angiography / Q000009:adverse effects*; D054059:Coronary Occlusion / Q000000981:diagnostic imaging / Q000628:therapy*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005471:Fluoroscopy / Q000009:adverse effects; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000209:etiology / Q000517:prevention & control*; D011834:Radiation Monitoring; D011835:Radiation Protection; D015641:Radiography, Interventional / Q000009:adverse effects*; D012107:Research Design; D012867:Skin / Q000528:radiation effects*; D013997:Time Factors