Advances in CT perfusion imaging and selection in acute ischemic stroke

CT perfusion (CTP), while holding promise for guiding treatment decisions in patients with acute ischemic stroke, presents with challenges and uncertainties in its diagnostic application. The thesis investigates the diagnostic accuracy, patient selection, and cost-effectiveness of CTP in managing acute ischemic stroke.
Part I evaluates the accuracy of various CTP software packages in estimating ischemic core volumes. We found significant variability in core volume estimates across different vendors, with moderate volumetric agreement but low spatial accuracy compared to MRI. These findings suggest that while CTP provides valuable insights, its results must be interpreted cautiously due to inconsistencies.
Part II examines the role of imaging in patient selection for endovascular treatment (EVT). We found that both larger CTP ischemic core volume and older age are associated with worse functional outcomes post-EVT. However, neither ischemic core volume nor age can reliably predict treatment effect. Moreover, we tested an automated algorithm for detecting large vessel occlusions, noting its high accuracy and speed. The study emphasizes that this algorithm should complement rather than replace clinical expertise.
Part III assesses the cost-effectiveness of using CTP for EVT selection, particularly within the first six hours of stroke onset. The findings indicate that excluding patients based on CTP-derived parameters does not lead to cost savings and may worsen outcomes, questioning the economic viability of CTP-based selection under current practices.
CTP can enhance the diagnostic process for acute ischemic stroke, but its results must be interpreted with care. Continued research into its clinical application will help refine its use.