BS EN IEC 62985:2019

Corrigendum 1. Methods for calculating size specific dose estimates (SSDE) for computed tomography. | Status: Current

1 Scope This document applies to

• — ct scanners that are able to display and report ctdivol in accordance with IEC 60601‑2‑44, and
• — radiation dose index monitoring software (RDIMS)

for the purpose of calculating, displaying and recording the size specific dose estimate (ssde) and its associated components. Specifically, this document provides standardized methods and requirements for calculating, displaying, or recording of ssde, ssde(z), water equivalent diameter (dw), and dw(z), where z represents a specific longitudinal position of the scanned object. This document provides a method of determining a reference water equivalent diameter, dw,ref(z), using ct scans of two cylindrical water phantoms and one or more anthropomorphic phantom(S), which conform to the specifications defined in this document. The method of calculating the water equivalent diameter that is implemented by the manufacturer, dw,imp(z), is tested and validated against dw,ref(z) using the test objects and methods defined within this document. This document also describes the methods for calculating ssde and dw, which represent the average values of ssde(z) and dw(z) over the reconstruction length.

NOTE This standardization is important to ensure that comparisons between reported ssdes are valid.