Use of Arterial Spin-Labeling in Patients with Aneurysmal Sub-arachnoid hemorrhage.

Delayed cerebral ischemia (DCI) due to cerebral vasospasm following aneurysmal subarachnoid hemorrhage (aSAH) has long been recognized as a major source of morbidity and mortality. Early detection of cerebral vasospasm and identification of patients who are likely to become symptomatic is crucial to guide aggressive medical and/or endovascular interventions. Magnetic resonance imaging using arterial spin-label (ASL) is a noninvasive mean for assessing cerebral blood flow and is based on direct magnetic labeling of arterial blood water protons. The diagnostic role of ASL in acute ischemic stroke, epilepsy, and neurodegenerative disorders has been explained in multiple studies but its ability to predict vasospasm in aSAH has not been published before. The purpose of this study is to highlight the diagnostic implications of different perfusion patterns of ASL in patients with aSAH which can be utilized to prevent DCI in such patients when other commonly used modalities are not available, contraindicated, or fail to detect vasospasm.

Cross-circulation thrombectomy with use of a stent retriever: A case report.

Introduction The efficacy of the endovascular treatment of acute ischemic stroke has been substantiated by several recent randomized clinical trials. While intra-arterial therapy has significantly evolved in recent years, anatomic cerebrovascular variants and disease burden can present challenges to timely recanalization. We present the first reported case of anterior-to-posterior mechanical clot retrieval with use of a stent retriever. Case description A 53-year-old man presented with basilar artery thrombosis. Endovascular mechanical clot retrieval was performed. The typical, antegrade, access to the basilar artery thrombus was precluded by the findings of a hypoplastic left vertebral artery and an occluded proximal right vertebral artery. Given a number of factors including the patient's worsening symptoms and the high morbidity and mortality associated with basilar stroke, cross-circulation-anterior-to-posterior-intra-arterial therapy was performed. Thrombectomy of the basilar thrombus was achieved via the right internal carotid artery and right posterior communicating artery. Conclusion To our knowledge, we report the first case of cross-circulation, anterior-to-posterior thrombectomy, with the use of a stent-retriever device. Cross-circulation stroke treatment may be beneficial in cases of proximal vessel occlusion or anatomical constraints. Larger studies will need to evaluate the safety and efficacy of these approaches.

Seizure Prophylaxis in the Immediate Post-Hemorrhagic Period in Patients with Aneurysmal Subarachnoid Hemorrhage.

INTRODUCTION: Seizures are a well-known complication of aneurysmal subarachnoid hemorrhage (aSAH) and occur most commonly in the immediate posthemorrhagic period. Most commonly used antiepileptic drugs (AEDs) for seizure prophylaxis in aSAH include phenytoin and levetiracetam. There is no reliable data available on the safety and efficacy of restricting AED prophylaxis only till the aneurysm is secured. METHODS: We retrospectively chart reviewed patients admitted to our neurosciences intensive care unit (NICU) with aSAH during the past two years. Seizure incidence was studied in patients treated with phenytoin versus levetiracetam and in patients treated for 3-7 days vs. those where AED was discontinued immediately after aneurysm was secured. RESULTS: In 28 patients, AED prophylaxis was discontinued immediately after the aneurysm was secured, and in 21 patients, it was continued for 3-7 days. Of the 28 patients who received AED prophylaxis for less than or equal to two days, phenytoin was used in 20 patients and levetiracetam was used in eight patients. In patients receiving AED prophylaxis for 3-7 days, phenytoin was used in eight cases and levetiracetam was used in 13 cases. None of these patients had seizures reported during hospitalization or at three-month follow-up. CONCLUSION: Stopping the AED prophylaxis immediately after aneurysm coiling is not associated with increased risk of seizures. Seizures at presentation in patients with aSAH are not associated with development of epilepsy at three months. Both phenytoin and levetiracetam are well tolerated in patients with aSAH when limited to the immediate posthemorrhagic period.

Granulomatous amebic encephalitis following hematopoietic stem cell transplantation.

BACKGROUND: Granulomatous amebic encephalitis (GAE) is rare, but often fatal. The infection has been documented predominantly among the immunocompromised population or among those with chronic disease. To date, however, there have only been eight cases regarding the infection following hematopoietic stem cell transplantation (HSCT). CASE DESCRIPTION: A 62-year-old female with a history of relapsed diffuse large B-cell lymphoma, recently underwent peripheral blood autologous stem cell transplant after BEAM conditioning (day 0). On day +15, she began to exhibit worsening fatigue, generalized weakness, and fever. Symptoms progressed to nausea, emesis, somnolence, confusion, and frontal headaches over the next few days. Imaging demonstrated multifocal ill-defined vasogenic edema with patchy enhancement. The patient was started on broad antibiotics, antifungals, and seizure prophylaxis. Evaluation for bacterial, fungal, mycobacterial, and viral etiologies was fruitless. Her mental status progressively deteriorated. On day +22, she exhibited severe lethargy and went into pulseless electrical activity arrest, requiring chest compressions. The episode lasted <2 min and her pulse was restored. She was taken to the operating room for a brain biopsy. Postoperatively, her right pupil began to dilate compared to the left; she demonstrated extensor posturing in her upper extremities and withdrawal in her lower extremities. Repeat computed tomography demonstrated progressive edema. Given poor prognosis and poor neurological examination, the family opted for withdrawal of care. Final pathology was consistent with Acanthamoeba GAE. CONCLUSION: The authors report the third case of GAE after autologous stem cell transplant, and the ninth case overall after HSCT. This case is unusual due to its rapid clinical presentation after HSCT compared to prior literature. The case highlights the need for high suspicion of Acanthamoeba infection in this patient population.