The impact of perfusion computed tomography on the diagnosis and outcome of delayed cerebral ischemia after subarachnoid hemorrhage.

BACKGROUND: Delayed cerebral ischemia (DCI) is a preventable cause of poor neurological outcome in aneurysmal subarachnoid hemorrhage (aSAH). Advances in radiological methods, such as cerebral perfusion computed tomography (CTP), could help diagnose DCI earlier and potentially improve outcomes in aSAH. The objective of this study was to assess whether the use of CTP to diagnose DCI early could reduce the risk of infarction related to DCI. METHODS: Retrospective cohort study of patients in the intensive care unit of Erasme Hospital (Brussels, Belgium) between 2004 and 2021 with aSAH who developed DCI. Patients were classified as: "group 1" - DCI diagnosed based on clinical deterioration or "group 2" - DCI diagnosed using CTP. The primary outcome was the development of infarction unrelated to the initial bleeding or surgery. RESULTS: 211 aSAH patients were diagnosed with DCI during the study period: 139 (66%) in group 1 and 72 (34%) in group 2. In group 1, 109 (78%) patients developed a cerebral infarction, compared to 45 (63%) in group 2 (p = 0.02). The adjusted cumulative incidence of DCI over time was lower in group 2 than in group 1 [hazard ratio 0.65 (95% CI 0.48-0.94); p = 0.02]. The use of CTP to diagnose DCI was not independently associated with mortality or neurological outcome. CONCLUSIONS: The use of CTP to diagnose DCI might help reduce the risk of developing cerebral infarction after aSAH, although the impact of such an approach on patient outcomes needs to be further demonstrated.

Intracranial Vessel Wall MRI in Cryptogenic Stroke and Intracranial Vasculitis.

INTRODUCTION: Intracranial vasculopathies easily elude classic stroke work-up. We aim in this work to show that vessel wall-MRI could prove an efficient alternative to digital subtraction angiography for the diagnosis of intracranial vasculopathies by identifying intracranial arterial vessel walls anomalies and contrast enhancement, suggestive of angiitis of the central nervous system. MATERIALS AND METHODS: Clinical and imaging characteristics of stroke patients diagnosed with primary angiitis of the central nervous system based on vessel wall-MRI were retrospectively reviewed and the clinical and imaging features of angiitis associated with intracranial vessel walls anomalies and contrast enhancement detailed. RESULTS: Twenty patients were included (mean age was 59 years old). All patients were admitted for focal neurological deficits of sudden onset that were recurrent in 13 subjects. Cognitive impairment, headache and seizures occurred in, respectively, 13, 5, and 2 patients. Cerebrospinal fluid analysis was abnormal in 15 patients. In MRI, FLAIR sequences showed ischemic infarcts in 20 patients and DWI showed acute infarct in 15 patients. Digital subtraction angiography was performed in 11 patients and disclosed proximal and distal multifocal stenosis in 10 patients along distal irregularities in different vascular territories in 7. For all of our patients, VW-MRI revealed a concentric contrast enhancement of arterial walls, localized in multiple vascular territories, suggesting angiitis. Abnormalities on digital subtraction angiography and/or MR-Angiography, and vessel wall-MRI were consistent in all patients. CONCLUSIONS: This report underlies the added value of vessel wall-MRI to the diagnosis of underlying intracranial vasculopathy, particularly primary angiitis of the central nervous system, without the use of invasive endovascular techniques and the yield of vessel wall-MRI in the work-up of cryptogenic stroke.