Matthew Lukas Hoimes MD, Presenter: Nothing to Disclose

Judith F. Katz MD, Abstract Co-Author: Nothing to Disclose

Richard H. Behrman PhD, Abstract Co-Author: Nothing to Disclose

To track the effective radiation dose (ERD) and model the risk of developing breast cancer in the female trauma population from exposure to low dose ionizing radiation from computed tomography (CT) pan scans following the inception of a new trauma center.

A generic trauma pan scan is defined as CT imaging of the head, cervical spine, chest, abdomen and pelvis (CAP) with reformatted images of the thoracic and lumbar spine. The PACS was searched over a one year period at Tufts Medical Center (Boston, MA) after it was designated as a trauma center. Pan scans performed on female trauma patients were identified. The patient’s age, scan indication, and scan findings were recorded. The DICOM images were processed using ImageJ ver. 1.38x. CT Acquisition parameters were extracted from the DICOM headers. This data was imported into ImPACT CT Patient Dosimetry Calculator ver. 0.99x and the ERD to the female breast (mSv) was calculated. Based on the ERD and the patient age, predictive models will be generated using the known models of excess relative risk per Sievert (ERR/Sv) as detailed in the BEIR VII Phase 2 report.

54 female trauma patients had CT pan scans over a one year period at Tufts Medical Center. The mean patient age was 51 ± 26 years. The leading indications were fall, motor vehicle collision, closed head injury, and pedestrian versus car. The ERD to the female breast of a representative 17 year old in a motor vehicle collision was 0.0013 mSv from the Head, 0.0055 mSv from the C-Spine, and 0.62 mSv from the CAP CT (totaling 0.63 mSv). Final ERD calculations of the entire data set are pending. Predictive models assessing the ERR/Sv of breast cancer in this population based on the BEIR VII Phase 2 study are also pending.

The ERD to the breast in the female trauma population at a new trauma center was tracked over a one year period. Initial analysis demonstrates most of the ERD to the breast is attributable to the CAP portion of the pan scan. Further analysis is required to explore how the ERR/Sv is related to the ERD and the age of exposure in this trauma population. This analysis will be facilitated utilizing the models in the BEIR VII phase 2 study.

CT pan scan use to triage trauma patients is rising. Tracking ERD to the breast may be a worthwhile endeavor to assess the long term risk to the female trauma population at your trauma center.

Hoimes, M, Katz, J, Behrman, R, Tracking Effective Radiation Dose to the Female Breast from Computed Tomography Pan Scans at a New Trauma Center.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6008072.html