title: Experimental estimates of peak skin dose and its relationship to the CT dose index using the CTDI head phantom.
abstract: A straightforward method is presented to estimate peak skin doses (PSDs) delivered by computed tomography (CT) scanners. The measured PSD values are related to the well-known volume CT dose index (CTDI(vol)), displayed on the console of CT scanners. PSD measurement estimates were obtained, in four CT units, by placing radiochromic film on the surface of a CTDI head phantom. Six different X-ray tube currents including the maximum allowed value were used to irradiate the phantom. PSD and CTDI(vol) were independently measured and later related to the CTDI(vol) value displayed on the console. A scanner-specific relationship was found between the measured PSD and the associated CTDI(vol) displayed on the console. The measured PSD values varied between 27 and 136 mGy among all scanners when the routine head scan parameters were used. The results of this work allow relating the widely used CTDI(vol) to an actual radiation dose delivered to the skin of a patient.
authors.affiliation: U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993, USA.
authors.forename: Hugo
authors.initials: H
authors.lastname: de las Heras
authors.forename: Ronaldo
authors.initials: R
authors.lastname: Minniti
authors.forename: Sean
authors.initials: S
authors.lastname: Wilson
authors.forename: Chad
authors.initials: C
authors.lastname: Mitchell
authors.forename: Marlene
authors.initials: M
authors.lastname: Skopec
authors.forename: Claudia C
authors.initials: CC
authors.lastname: Brunner
authors.forename: Kish
authors.initials: K
authors.lastname: Chakrabarti
mesh_terms: D002138:Calibration; D005373:Film Dosimetry; D006257:Head / Q000000981:diagnostic imaging*; D006801:Humans; D007477:Ions; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D015203:Reproducibility of Results; D012867:Skin / Q000000981:diagnostic imaging* / Q000528:radiation effects*; D015898:Tomography Scanners, X-Ray Computed; D014057:Tomography, X-Ray Computed; D014965:X-Rays
chemical_list: D007477:Ions