This chapter contains sections titled: Symptomatic versus asymptomatic aneurysms Theories of aneurysm initiation and lifecycle Therapeutic correction of blood flow Conclusions References
Stroke has become an absolute emergency that is treated by additional endovascular means or by replacing pharmacological options. Modern neuroradiological techniques such as computed tomography (CT) allow us to examine multiple parameters of the diseased brain. These focused on the parenchyma and hemodynamics for pretherapeutic decisions. However, it has become evident that the clot is the current target for interventional measures. Clot length is established as a marker for recanalization. The dense artery sign is known as an acute CT sign of stroke that is readily visible on acute nonenhanced CT. The rationale behind our study was to study if clot density might represent clot vulnerability or resistance to treatment. We conducted a prospective study of all consecutive stroke patients admitted to our hospital over 1 year, who presented with signs of acute middle cerebral artery stroke within the therapeutic window, and who underwent either intravenous or combined intravenous and intra-arterial thrombolysis. All patients were evaluated with a complete stroke CT protocol, transcranial color-coded duplex sonography monitoring, and clinical evaluation with the National Institutes of Health Stroke Scale (NIHSS) score. We measured clot length using planimetry on unenhanced CT and measured Hounsfield units in the clots on the same images. A total of 31 patients were included in the study (19 men, 12 women, aged 35–90 years). We found that patients with a longer clot on the unenhanced CT had a higher NIHSS score, confirming previous literature. However, we found that patients with a lower clot density recanalized to a more marked degree and had a better clinical outcome. Patients who did not recanalize had a higher clot density (49 Hounsfield units) than those who did recanalize (23 Hounsfield units). Overall, measuring the clot seems to be an important additional parameter to be taken into account. In our study, CT clot density seems to correlate with clinical outcome and recanalization. The higher density seems to represent a higher red blood cell content. This is evidence that clot composition could play a much more important role in acute stroke than thought until now and characterizing it with imaging may help in choosing the adequate treatment modality. Higher density seems to reflect erythrocyte content. Therefore, patients with a longer and denser clot may necessitate direct thrombectomy.
Studies investigating endovascular therapy in vertebro-basilar stroke have led to controversial results in the past, but recent randomized trials seem to show an effectiveness superiority of endovascular therapy versus best medical treatment. However, uncertainty remains concerning many aspects of thrombectomy in acute basilar artery occlusion, notably technical considerations. This study compared the first-pass effect of direct thromboaspiration and combined thrombectomy in the setting of distal basilar occlusion.
Background and purpose The purpose of this study was to assess the initial post-market experience of the device and how it is compared with the Penumbra Pivotal trial used to support the 510k application. Methods A retrospective case review of 157 consecutive patients treated with the Penumbra system at seven international centers was performed. Primary endpoints were revascularization of the target vessel (TIMI score of 2 or 3), good functional outcome as defined by a modified Rankin scale (mRS) score of ≤2 and incidence of procedural serious adverse events. Results were compared with those of the Penumbra pivotal trial. Results A total of 157 vessels were treated. Mean baseline values at enrollment were: age 65 years, NIHSS score 16. After use of the Penumbra system, 87% of the treated vessels were revascularized to TIMI 2 (54%) or 3 (33%) as compared with 82% reported in the Pivotal trial. Nine procedural serious adverse events were reported in 157 patients (5.7%). All-cause mortality was 20% (32/157), and 41% had a mRS of ≤2 at 90-day follow-up as compared with only 25% in the Pivotal trial. Patients who were successfully revascularized by the Penumbra system had significantly better outcomes than those who were not. Conclusion Initial post-market experience of the Penumbra system revealed that the revascularization rate and safety profile of the device are comparable to those reported in the Pivotal trial. However, the proportion of patients who had good functional outcome was higher than expected.
Ischemic stroke is a leading cause of death and disability worldwide. Much of the long-term disability occurs in patients with Emergent Large Vessel Occlusion (ELVO). In fact, in these patients, occlusion of a major intracerebral artery results in a large area of brain injury often resulting in
MRI is negative in a large percentage of autoimmune encephalitis cases or lacks findings specific to an antibody. Even rarer is literature correlating the evolution of imaging findings with treatment timepoints. We aim to characterize imaging findings in autoimmune encephalitis at presentation and on follow up correlated with treatment timepoints for this rare disease.
