Estimation of Peak Skin Dose and Its Relation to the Size-Specific Dose Estimate

Abstract

The study tests the concept that the size-specific dose estimate (SSDE) and the Computed Tomography Dose Index volume (CTDIvol) have a significant association with the peak skin dose (PSD). To determine the relationship between the two measurements, the National Electrical Manufacturers Association (NEMA) phantom and the American College of Radiology (ACR) phantom were used with a Computed Tomography (CT) scanner. The PSD was measured using external Nanodot dosimeters which use optically stimulated luminescence (OSL) technology. The OSL Nanodots dosimeters were placed in three different locations on the phantom (anterior, posterior, and lateral). To help ensure the robustness of the findings, different measuring techniques and quantification methods were utilized in the research. The aim was to compare the measured PSD to Size Specific Dose Estimates, and test if a correlation exists. An assessment of a correlation between PSD and both CTDIvol and Dose Length Product was done as well. If there is a reasonable level of correlation, a mathematical formula will be derived to estimate the Peak Skin Dose from the CT console. In fact, The CT output (the dose) which is used according to the protocol is the CTDI, but in order to have the overall dose of either a patient or a phantom, the dimensions of the patient are needed to calculate the overall dose (SSDE).