the purpose
Among the many rights related to medical radiation exposure, there are the "right to be provided with information" and the "duty to promote understanding." Based on these rights and obligations, we have created this guide for the purpose of helping medical professionals respond to questions from patients and recognize their own exposure doses. The X-ray dose calculator is a simple model compatible with OverTube. Please use it to calculate the irradiation dose and side fluoroscopy scattered dose (side scattered dose) immediately after the examination using X-ray imaging or fluoroscopy, which is commonly used in medical treatment. Please use the values as reference values. We also hope that it will be of assistance in following the "Guidelines for the formulation of guidelines for the safe use of medical radiation. Iseiji Issue No. 1003 No. 5, October 3, 2020."
1. Overview
Patient: This is the breakdown and total value of the incident surface dose for imaging and fluoroscopy for a body thickness of 20 cm.
Caregiver: Side perspective scattered radiation is when not wearing protective clothing. Dose while wearing protective clothing calculates the working dose of medical workers when wearing protective clothing.
(Calculation method)
Incident surface dose: Calculated by reconstructing using an approximation function based on the calculated value.
Side perspective scattered dose/protective clothing wearing dose: Calculated using an approximate formula function using X-ray air kerma transmittance (lead) based on actual measurements.
Calculation formula: D=Xair×1/FSD^2×Cf×BSF, D: Incident surface dose (Gy), Xair: Irradiation dose in the air at a distance of 1 m from the focal point (C/kg), FSD: Focus-incidence surface distance (m), Cf: Absorbed dose conversion coefficient (Gy/C/kg), BSF: Backscattering coefficient
Measuring device: Ionization chamber survey meter (Fluke Biomedial 451P-DE-SIRYR)
2. How to operate
Incident surface dose: After tapping the patient, tap Imaging or Fluoroscopy. Follow the instructions in the app and enter the Shot section, then tap Start dose calculation. The screen will change to the dose calculation result (patient) and the dose will be displayed. If you return to the dose calculation start screen with ← on the top left and perform the same calculation for the patient, the previous total will be displayed on the dose calculation result screen. The details are shown in the column below, and the calculations made earlier are shown below. If it is not cleared, it will be added to the bottom of the column.
Side perspective scattered dose/protective clothing dose: Tap the caregiver. Enter the distance, voltage, current exposure time, and lead equivalent of protective clothing. Tap Start dose calculation. Dose calculation result (caregiver) screen appears. If it is not cleared, it will be added below.
In any case, when calculating a new value, please tap Clear Total.