Results of a multicenter 4D computed tomography quality assurance audit: Evaluating image accuracy and consistency.

Background And Purpose: 4D Computed Tomography (4DCT) technology captures the location and movement of tumors and nearby organs at risk over time. In this study, a multi-institutional multi-vendor 4DCT audit was initiated to assess the accuracy of current imaging protocols.

Materials And Methods: Twelve centers, including thirteen scanners performed a 4DCT acquisition of a dynamic thorax phantom using the institution's own protocol with the in-house breathing monitoring system.

A comprehensive quality assurance program for four-dimensional computed tomography in radiotherapy.

This study aimed to develop and validate a comprehensive, reproducible and automatic 4DCT Quality Assurance (QA) workflow (QAMotion) that evaluates image accuracy across various regular and irregular breathing patterns. Volume and amplitude deviations, CT number accuracy, and spatial integrity were used as evaluation metrics. For repeatability tests, tolerances were respected with a mean CT number deviation < 10 HU, volume deviation < 2% and diameter and amplitude deviation < 2 mm except for irregular amplitude curves for which an amplitude deviation up to 6 mm was measured.