SU-F-I-33: Estimating Radiation Dose in Abdominal Fat Quantitative CT
- Massachusetts General Hospital, Boston, MA (United States)
Purpose: To compare size-specific dose estimate (SSDE) in abdominal fat quantitative CT with another dose estimate D{sub size,L} that also takes into account scan length. Methods: This study complied with the requirements of the Health Insurance Portability and Accountability Act. At our institution, abdominal fat CT is performed with scan length = 1 cm and CTDI{sub vol} = 4.66 mGy (referenced to body CTDI phantom). A previously developed CT simulation program was used to simulate single rotation axial scans of 6–55 cm diameter water cylinders, and dose integral of the longitudinal dose profile over the central 1 cm length was used to predict the dose at the center of one-cm scan range. SSDE and D{sub size,L} were assessed for 182 consecutive abdominal fat CT examinations with mean water-equivalent diameter (WED) of 27.8 cm ± 6.0 (range, 17.9 - 42.2 cm). Patient age ranged from 18 to 75 years, and weight ranged from 39 to 163 kg. Results: Mean SSDE was 6.37 mGy ± 1.33 (range, 3.67–8.95 mGy); mean D{sub size,L} was 2.99 mGy ± 0.85 (range, 1.48 - 4.88 mGy); and mean D{sub size,L}/SSDE ratio was 0.46 ± 0.04 (range, 0.40 - 0.55). Conclusion: The conversion factors for size-specific dose estimate in AAPM Report No. 204 were generated using 15 - 30 cm scan lengths. One needs to be cautious in applying SSDE to small length CT scans. For abdominal fat CT, SSDE was 80–150% higher than the dose of 1 cm scan length.
- OSTI ID:
- 22626794
- Journal Information:
- Medical Physics, Journal Name: Medical Physics Journal Issue: 6 Vol. 43; ISSN 0094-2405; ISSN MPHYA6
- Country of Publication:
- United States
- Language:
- English
Similar Records
TU-F-CAMPUS-I-03: Preliminary Study of Size-Specific Dose Estimates in Adult Abdomenal CT Examinations in Taiwan
MO-E-17A-01: BEST IN PHYSICS (IMAGING) - Calculating SSDE From CT Exams Using Size Data Available in the DICOM Header of CT Localizer Radiographs
MO-FG-CAMPUS-IeP2-02: Effects of Metal On CT Size-Specific Dose Estimates
Journal Article
·
Mon Jun 15 00:00:00 EDT 2015
· Medical Physics
·
OSTI ID:22570052
MO-E-17A-01: BEST IN PHYSICS (IMAGING) - Calculating SSDE From CT Exams Using Size Data Available in the DICOM Header of CT Localizer Radiographs
Journal Article
·
Sun Jun 15 00:00:00 EDT 2014
· Medical Physics
·
OSTI ID:22407780
MO-FG-CAMPUS-IeP2-02: Effects of Metal On CT Size-Specific Dose Estimates
Journal Article
·
Wed Jun 15 00:00:00 EDT 2016
· Medical Physics
·
OSTI ID:22653898