Stroke thrombectomy : new devices, imaging, scoring system and outcomes in the older population

Abstract

In the past several years there have been major developments in the interventional treatment of acute ischaemic stroke. This thesis consists of four projects that I developed throughout my graduate studies. I started by working on setting up a phase 2 multicentre, randomised, controlled trial to assess the technical safety and efficacy of two new devices to be used in endovascular treatment: the ERIC retriever and the SOFIA distal access catheter. The trial has not yet finished, but partial results are presented. I went on to investigate the role of imaging in hyperacute stroke management. I developed a validated case archive of computed tomography angiography scans which was used for a radiological course. Assessing trainees reports pre- and post-training showed that there was a significant improvement in rates of major errors and this study concluded that an intensive hands-on radiological course was effective. While the trial was running, I developed a new technical index of thrombectomy difficulty. This score uses computed tomography angiographic images to evaluate key factors for predicting the expected procedural difficulty. The results demonstrated an excellent inter-rater reliability making this potentially a powerful tool to help with decision making and procedural planning. Due to limited evidence for mechanical thrombectomy in the older population, I worked on a study to assess the safety and efficacy of this treatment. Patients had more comorbidities, more tandem occlusions, but still good reperfusion rates with a similar safety profile to the younger population. Clinical results at 3 months were poorer than in the younger population, but milder presenting clinical deficits and good reperfusion rates were predictors of good outcomes. This thesis will first discuss stroke with a review of the evidence for performing mechanical thrombectomy. The projects undertaken during my studies will be discussed and I will finish with a succinct conclusion.