Intravenous contrast media in radiation therapy planning computed tomography scans – Current practice in Ireland

Abstract

Introduction: While Computerised Tomography (CT) remains the gold standard in radiation therapy (RT) planning, inferior soft tissue definition remains a challenge. Intravenous contrast (IVC) use during CT planning can enhance soft tissue contrast optimising Target Volume (TV) and Organ at Risk visualisation and delineation. Despite this known benefit, there are no guidelines for when and how to use IVC in RT planning scans in Ireland. Aim: The study aims to examine the patterns of practice in relation to the use of IVC in RT planning scans in Ireland and to determine the level of compliance with international guidelines. Radiation Therapists (RTT) IVC training will also be investigated. Materials and methods: An anonymised online survey was designed based on previously-reported literature. This was distributed to all RT departments in Ireland. The survey contained open, closed and Likert scale questions that investigated IVC practices in each department. Results: 75% (n = 9/12) of Irish departments responded. All responding departments reported using IVC. RTTs cannulated patients in 67% (n = 6/9) of the departments and administration contrast in all departments. Variations from recommended guidelines were found in disease sites where IVC was routinely used and in the assessment of renal functioning prior to contrast administration. IVC training varied in duration and number of supervised procedures required to fulfill competencies. Conclusion: IVC is used extensively in Irish RT departments. There are variations in IVC practice between departments and with international recommended guidelines. Keywords: Intravenous contrast, Radiation therapy treatment planning scan, Computerised tomography, Target volume delineation, Radiation therapists’ practice