title: Effect of an arm traction device on image quality and radiation exposure during neck computed tomography.
abstract: OBJECTIVE
  To retrospectively determine the effect of an arm traction device on image quality and radiation exposure during a neck computed tomography (CT) scan.
  
  
  METHODS
  Standard neck CT examinations with an automatic tube current modulation technique were compared for two groups (intervention group: patients with an arm traction device, n=45; control group: no particular positioning optimization, n=45). Image quality was the primary outcome and was assessed using image noise and the streak artifact. The secondary outcome was radiation exposure, which was measured by the volume CT dose index (CTDIvol) and dose-length product. Potential confounders, including the effective diameter of the neck and scan length, were also assessed.
  
  
  RESULTS
  Image noise and the streak artifact at the lower neck and the supraclavicular fossa were significantly improved in the intervention group compared with the control group (p<0.001). There was a significant decrease in the CTDIvol in the intervention group versus the control group (p=0.042). DLP showed a tendency toward a decrease in the intervention group that was non-significant (p=0.106). The effective diameter and scan length showed no statistical difference between the two groups.
  
  
  CONCLUSIONS
  An arm traction device improves the image quality in the lower neck and the supraclavicular fossa during a neck CT. Application of this device also reduces the tendency for radiation exposure.
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Republic of Korea.
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Choi
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Republic of Korea. Electronic address: jeonghlee@amc.seoul.kr.
authors.forename: Jeong Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Republic of Korea.
authors.forename: Woong Yong
authors.initials: WY
authors.lastname: Cho
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Republic of Korea.
authors.forename: Jung Hwan
authors.initials: JH
authors.lastname: Baek
mesh_terms: D000328:Adult; D000368:Aged; D001132:Arm / Q000000981:diagnostic imaging; D016477:Artifacts; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009333:Neck / Q000000981:diagnostic imaging*; D056888:Patient Positioning / Q000379:methods*; D011829:Radiation Dosage; D000069079:Radiation Exposure; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods; D014143:Traction
keywords: Artifact; Computed tomography (CT); Head and neck; Image quality; Radiation dose