Adapting Clinical Practice of Thrombolysis for Acute Ischemic Stroke Beyond 4.5 Hours: A Review of the Literature.

Several clinical trials have demonstrated that advanced neuroimaging can select patients for recanalization therapy in an extended time window. The favorable functional outcomes and safety profile of these studies have led to the incorporation of neuroimaging in endovascular treatment guidelines, and most recently, also extended to decision making on thrombolysis. Two randomized clinical trials have demonstrated that patients who are not amenable to endovascular thrombectomy within 4.5 hours from symptoms discovery or beyond 4.5 hours from the last-known-well time may also be safely treated with intravenous thrombolysis and have a clinical benefit above the risk of safety concerns. With the growing aging population, increased stroke incidence in the young, and the impact of evolving medical practice, healthcare and stroke systems of care need to adapt continuously to provide evidence-based care efficiently. Therefore, understanding and incorporating appropriate screening strategies is critical for the prompt recognition of potentially eligible patients for extended-window intravenous thrombolysis. Here we review the clinical trial evidence for thrombolysis for acute ischemic stroke in the extended time window and provide a review of new enrolling clinical trials that include thrombolysis intervention beyond the 4.5 hour window.

Iodinated Contrast Extravasation on Post-Revascularization Computed Tomography Mimics Magnetic Resonance Hyperintense Acute Reperfusion Marker: A Case Study.

Hyperintense reperfusion marker (HARM) on post-contrast magnetic resonance imaging (MRI) fluid attenuated inversion recovery (FLAIR) represents gadolinium contrast extravasation in the setting of acute ischemic stroke and is a common finding after revascularization therapies. Clinically, it is a marker of blood brain barrier (BBB) disruption, predictor of hemorrhagic transformation, and predictor of poor clinical outcome in ischemic stroke. Here, we describe a case where a patient underwent mechanical thrombectomy and was later found to have evidence of contrast extravasation on CT imaging, in the same locations found on the post-contrast FLAIR MRI, demonstrating that MRI-HARM and CT contrast extravasation may mimic similar phenomena. Thus, this case demonstrates that we may be able to extrapolate what we know about HARM detected on MRI to a CT imaging biomarker that would be more readily obtainable in most stroke patients.

Small-vessel disease in the brain.

Cerebral small-vessels are generally located in the brain at branch points from major cerebral blood vessels and perfuse subcortical structures such as the white matter tracts, basal ganglia, thalamus, and pons. Cerebral small-vessel disease (CSVD) can lead to several different clinical manifestations including ischemic lacunar stroke, intracerebral hemorrhage, and vascular dementia. Risk factors for CSVD overlap with conventional vascular risk factors including hypertension, diabetes mellitus, and hypercholesterolemia, as well as genetic causes. As in cardiovascular disease, treatment of CSVD involves both primary and secondary prevention. Aspirin has not been established as a primary prevention strategy for CSVD among the general population; however, long-term antiplatelet therapy with aspirin alone continues to be the mainstay of secondary stroke prevention for non-cardioembolic ischemic stroke and high-risk TIA.

Subacute Posterior Inferior Cerebellar Artery Stroke Radiographically Mimicking Lhermitte-Duclos Disease.

Lhermitte-Duclos disease (LDD) is a rare cerebellar lesion characterized by a hamartomatous lesion of the cerebellum. Mainly diagnosed by MRI, the clinical presentation is usually made of neurological symptoms. Modern neuroimaging techniques such as MRI have led to accurate diagnosis of this disease in both its pre- and post-operative periods. We present the case of a 68-year-old male with a past medical history of cardiac stenting and coronary artery disease who originally presented to the emergency department as a transfer for evaluation of possible obstructing hydrocephalus and left posterior inferior cerebellar artery (PICA) infarct. Based on the clinical presentation and imaging, the favored diagnosis of his left cerebellar abnormality was LDD rather than an unusual acute/subacute infarct or a metastatic lesion. The rapid progression of symptoms with rapidly progressive cytotoxic edema on serial CTs helped exclude LDD, which is nearly always more of a chronic process. The classic neuroimaging findings and clinical presentation of LDD are also discussed.

Management of Cavernous Sinus Thrombosis Following Herpes Zoster Ophthalmicus.

Herpes zoster opthalmicus (HZO) is the reactivation of latent varicella zoster virus (VZV) within the ophthalmic branch of the trigeminal ganglion (V1). Common complications are postherpetic neuralgia and vasculopathy. Here, we report a rare case of a 47-year-old female presenting with HZO and aseptic cavernous sinus thrombosis (CST). Early screening for rare and deadly complications such as CST using CT cerebral venography (CTV) and magnetic resonance venography (MRV), as was done, is crucial to detection at earlier stages when intervention is most effective. Anticoagulation therapy was promptly started, and the patient's symptoms continued to improve during the hospital stay.

Cryptococcosis Presenting as Cerebrovascular Disease.

Infection plays a complex role in cerebrovascular disease and is believed to have both direct and indirect mechanisms on stroke pathogenesis. if not diagnosed and treated promptly, this may have devastating consequences. Management of infection-related strokes focuses on the treatment of the underlying infection with appropriate antimicrobial drugs and the prevention of medical complications. This can lead to devastating neurological deficits. We present two cases of cryptococcal meningoencephalitis that presented with an atypical cerebral infarction. A 55-year-old male with a history of unknown autoimmune disease presented with acute onset cognitive changes and no stroke-like symptoms. A 35-year-old male with no history of autoimmune disease or other existing immunodeficiency presented with breakthrough seizure a long with stroke-like symptoms. Both patients developed multiple cerebral infarcts in multiple vascular territories, with histologic and radiologic findings consistent with a central nervous system cryptococcosis. They were subsequently diagnosed with cryptococcal meningoencephalitis and started on the appropriate anti-fungal regimen with amphotericin B and flucytosine. Prior to discharge to an inpatient rehabilitation facility, both patients were notably improved and near their neurologic baseline. It is important to understand the pathogenesis of cryptococcal infection in the central nervous system because it produces a wide variety of clinico-radiographic features that can be overlooked. Clinicians should keep infection-mediated cerebral infarcts in mind, regardless of risk factors, in order to expedite antimicrobial therapy and minimize adverse events.