title: Excess radiation and organ dose in chest and abdominal CT due to CT acquisition beyond expected anatomical boundaries.
abstract: OBJECTIVE
  To assess the extent of extra imaging beyond the prescribed anatomical margins for chest and abdominal CT and to determine associated extra patient and organ dose estimates.
  
  
  METHODS
  For 167 consecutive patients undergoing routine chest and/or abdominal examination with 128-slice CT, extra imaging length was evaluated on coronal images. Effective and organ doses (thyroid, liver, breasts, testes) were calculated. Paired t-test was applied to evaluate statistically significant differences between prescribed and actual imaging length, and associated doses.
  
  
  RESULTS
  133 (80%) examinations had extra coverage (mean 4.6 cm, range 1-19.5 cm). Significantly higher (P < 0.05) effective doses for chest CT (mean 4.8 mSv vs 4.2 mSv for actual vs prescribed volume of interest), abdominal CT (8.4 mSv vs 7.9 mSv) or thorax-abdominal CT (12.8 mSv vs 11.9 mSv) were found. A significantly higher (P < 0.001) organ dose was estimated for thyroid (extra dose 99% corresponding to 5.1 mSv), liver (56%, 2.2 mSv), testes (115%, 7.6 mSv), and breasts (163%, 1.5 mSv).
  
  
  CONCLUSIONS
  Imaging beyond anatomical limits during routine chest and abdominal CT results in higher organ and effective doses. Continuous training of the technologists remains important. Physicians and technologists must be kept aware of the additional dose associated with extra imaging.
  
  
  CONCLUSIONS
  Imaging beyond anatomical boundaries often occurs during chest and abdominal CT. Such imaging beyond anatomical boundaries leads to higher organ and effective doses. Physicians and technologists should be made more aware of this additional dose.
authors: Department of Radiology, University Hospitals Leuven, 3000, Leuven, Belgium. federica.zanca@uzleuven.be
authors: Federica
authors: F
authors: Zanca
authors: Martine
authors: M
authors: Demeter
authors: Raymond
authors: R
authors: Oyen
authors: Hilde
authors: H
authors: Bosmans
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001530:Belgium / Q000453:epidemiology; D001822:Body Burden; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058958:Organs at Risk; D011829:Radiation Dosage; D011860:Radiography, Abdominal / Q000706:statistics & numerical data*; D013902:Radiography, Thoracic / Q000706:statistics & numerical data*; D011874:Radiometry / Q000706:statistics & numerical data*; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data*; D055815:Young Adult