title: Radiation dose from volumetric helical perfusion CT of the thorax, abdomen or pelvis.
abstract: OBJECTIVE
  To evaluate the radiation doses delivered during volumetric helical perfusion CT of the thorax, abdomen or pelvis.
  
  
  METHODS
  The dose-length product (DLP) and CT dose index (CTDIvol) were recorded and effective dose (E) determined for patients undergoing CT (4D adaptive spiral) for tumour evaluation. Image noise and contrast to noise (CNR) at peak enhancement were also assessed for quality.
  
  
  RESULTS
  Forty two consecutive examinations were included: thorax (16), abdomen (10), pelvis (16). Z-axis coverage ranged from 11.4 to 15.7 cm. Mean DLP was 1288.8 mGy.cm (range: 648 to 2456 mGy.cm). Mean CTDIvol was 96.2 mGy (range: 32.3 to 169.4 mGy). Mean effective dose was 19.6 mSv (range: 12.3 mSv to 36.7 mSv). In comparison mean DLP and effective dose was 885.2 mGy.cm (range: 504 to 1633 mGy.cm) and 13.3 mSV (range: 7.8 to 24.5 mSv) respectively for the standard staging CT thorax, abdomen and pelvis. Mean tumour CNR at peak enhancement was 1.87.
  
  
  CONCLUSIONS
  The radiation dose imposed by perfusion CT was on average 1.5 times that of a CT thorax, abdomen and pelvis. The dose is not insubstantial, and must be balanced by the potential clinical utility of additional physiologic data. Further efforts towards dose reduction should be encouraged.
authors.affiliation: Paul Strickland Scanner Centre, Mount Vernon Hospital, Rickmansworth Road, Northwood, Middlesex HA6 2RN, UK. vicky.goh@stricklandscanner.org.uk
authors.forename: Vicky
authors.initials: V
authors.lastname: Goh
authors.forename: Minaxi
authors.initials: M
authors.lastname: Dattani
authors.forename: Joseph
authors.initials: J
authors.lastname: Farwell
authors.forename: Jane
authors.initials: J
authors.lastname: Shekhdar
authors.forename: Emily
authors.initials: E
authors.lastname: Tam
authors.forename: Shilpan
authors.initials: S
authors.lastname: Patel
authors.forename: Jaspal
authors.initials: J
authors.lastname: Juttla
authors.forename: Ian
authors.initials: I
authors.lastname: Simcock
authors.forename: James
authors.initials: J
authors.lastname: Stirling
authors.forename: Henry
authors.initials: H
authors.lastname: Mandeville
authors.forename: Edwin
authors.initials: E
authors.lastname: Aird
authors.forename: P
authors.initials: P
authors.lastname: Hoskin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging*; D010388:Pelvis / Q000000981:diagnostic imaging*; D010477:Perfusion; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011860:Radiography, Abdominal / Q000379:methods*; D013902:Radiography, Thoracic / Q000379:methods*; D036542:Tomography, Spiral Computed / Q000379:methods*