Volume variation may be a relevant metric in the study of aneurysm pulsatility: Results of a pilot study

Abstract

Purpose Intracranial aneurysms are frequent with a prevalence estimated over 2–5% in the general population. They usually remain silent until rupture occurs with a mortality rate of 35–50% and a high rate of morbidity including long-term disability. However, preventative treatments have their own risk of complication and morbi-mortality rate including stroke and hemorrhage. ECG-gated 4D CTA allows acquisition of time-resolved 3D reconstructions. The aim of our study is to evaluate different intracranial aneurysm metrics over cardiac cycle using ECG-gated 4D-CTA. Materials and methods ECG-gated 4D-CTA datasets were acquired in patients presenting with intracranial aneurysms. Seven aneurysm metrics including height, length, width, ostium area, volume aspect ratio and volume ostium ratio were analyzed for different cardiac phases. An intra-reader agreement, inter-reader agreement and inter-cycles agreement were calculated through intraclass correlation coefficient. Results Twenty one aneurysms from 11 patients were considered for inclusion. The post-processing failed for 3 aneurysms, and eighteen aneurysms were analyzed. There were significant differences between the minimum and the maximum of every metrics during the cardiac cycle (P 0.9). Agreements between three following cardiac cycles were calculated for 6 aneurysms and was especially good for the volume (ICC > 0.9). Conclusions Aneurysm volume changes over cardiac cycle is quantitatively possible and a reproducible measurement. Further studies need to be conducted to evaluate this new parameter for intracranial aneurysm assessment.