229 research outputs found
Endovascular Cure of a Locked-In Patient
We report the case of a 60 year-old right-handed gentleman who became acutely “Locked-In” several days after a lower extremity orthopedic procedure. He underwent emergent endovascular treatment and had complete resolution of his neurologic findings except for mild dysarthria and dysphagia. Endovascular intervention for posterior circulation thrombosis is highly effective when patients are treated within 24 hours
Hemorrhagic stroke—Pathomechanisms of injury and therapeutic options
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151916/1/cns13225_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151916/2/cns13225.pd
Understanding Neurosurgery Through Experimental and Computer Models
Endovascular neurosurgery is an evolving field, with the goal of treating neurological disease with minimal invasion of the body. The current approach is to deliver focused therapies via catheters traveling through the vascular tree. Refinement and advancement of these techniques requires not just new ideas, but new ideas that hold up when tested through the scientific method.
Before clinical trials can begin, ethics and law demand that the ideas are tested first under experimental models. One benefit of these pre-clinical tests is the early identification of side effects. Another is the opportunity to practice and polish surgical technique in advance of human surgery.
Historically, the best models of human systems have been similar systems in appropriate animals. Like human care, animal use is governed by strict laws and regulations. Violating these rules can not only result in criminal penalties, they can also make the research worthless: an animal poorly cared for may have physical symptoms that mask or confound the response to treatment.
As computing power has increased, mathematical models have become more popular. The advantages of computational models include relative costs and relative speed. No animals, drugs or equipment have to be purchased, just a computer and software. The disadvantage is that the computational model can only represent those aspects of the modeled system that are understood and quantifiable.
This article is an overview of how both animal and computational models have been used to approximate neurovascular conditions by researchers seeking to explore treatment options
Case Report: Signal Drop on MRA Imaging of the Internal Carotid Artery after Neuroform Stent Placement
Magnetic resonance angiography (MRA) is an important tool in evaluating the patency of vessels which have previously been stented. Neuroform stents (Boston Scientific, Natick, MA, U.S.A.) are utilized to provide a scaffold across the neck of an aneurysm. These stents are synthesized from Nitinol (nickel and titanium) and thus cause minimal distortion upon imaging with MRA. Patients who have undergone Neuroform stent assisted coiling of aneurysms are routinely followed with MRA to delineate stenosis of the stented segment of vessel as well as recurrence of the aneurysms. While numerous reports show that Neuroform stents do not lead to MRA imaging artifact, we report of a case where the utilization of the Neuroform stent led to a signal drop out at the site of the stent upon evaluation with MRA and thus led to further invasive radiological procedures
Clinical and experimental aspects of aneurysmal subarachnoid hemorrhage
Aneurysmal subarachnoid hemorrhage (aSAH) continues to be associated with significant morbidity and mortality despite advances in care and aneurysm treatment strategies. Cerebral vasospasm continues to be a major source of clinical worsening in patients. We intended to review the clinical and experimental aspects of aSAH and identify strategies that are being evaluated for the treatment of vasospasm. A literature review on aSAH and cerebral vasospasm was performed. Available treatments for aSAH continue to expand as research continues to identify new therapeutic targets. Oral nimodipine is the primary medication used in practice given its neuroprotective properties. Transluminal balloon angioplasty is widely utilized in patients with symptomatic vasospasm and ischemia. Prophylactic “triple‐H” therapy, clazosentan, and intraarterial papaverine have fallen out of practice. Trials have not shown strong evidence supporting magnesium or statins. Other calcium channel blockers, milrinone, tirilazad, fasudil, cilostazol, albumin, eicosapentaenoic acid, erythropoietin, corticosteroids, minocycline, deferoxamine, intrathecal thrombolytics, need to be further investigated. Many of the current experimental drugs may have significant roles in the treatment algorithm, and further clinical trials are needed. There is growing evidence supporting that early brain injury in aSAH may lead to significant morbidity and mortality, and this needs to be explored further.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151874/1/cns13222_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151874/2/cns13222.pd
Dosimetric measurements of Onyx embolization material for stereotactic radiosurgery
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135017/1/mp7918.pd
Neuroendovascular clinical trials disruptions due to COVID-19. Potential future challenges and opportunities
Objective: To assess the impact of COVID-19 on neurovascular research and deal with the challenges imposed by the pandemic.
Methods: A survey-based study focused on randomized controlled trials (RCTs) and single-arm studies for acute ischemic stroke and cerebral aneurysms was developed by a group of senior neurointerventionalists and sent to sites identified through the clinical trials website (https:// clinicaltrials. gov/), study sponsors, and physician investigators.
Results: The survey was sent to 101 institutions, with 65 responding (64%). Stroke RCTs were being conducted at 40 (62%) sites, aneurysm RCTs at 22 (34%) sites, stroke single-arm studies at 37 (57%) sites, and aneurysm single-arm studies at 43 (66%) sites. Following COVID-19, enrollment was suspended at 51 (78%) sites—completely at 21 (32%) and partially at 30 (46%) sites. Missed trial-related clinics and imaging follow-ups and protocol deviations were reported by 27 (42%), 24 (37%), and 27 (42%) sites, respectively. Negative reimbursements were reported at 17 (26%) sites. The majority of sites, 49 (75%), had put new trials on hold. Of the coordinators, 41 (63%) worked from home and 20 (31%) reported a personal financial impact. Remote consent was possible for some studies at 34 (52%) sites and for all studies at 5 (8%) sites. At sites with suspended trials (n=51), endovascular treatment without enrollment occurred at 31 (61%) sites for stroke and 23 (45%) sites for aneurysms. A total of 277 patients with acute ischemic stroke and 184 with cerebral aneurysms were treated without consideration for trial enrollment.
Conclusion: Widespread disruption of neuroendovascular trials occurred because of COVID-19. As sites resume clinical research, steps to mitigate similar challenges in the future should be considered
Urinary Exosomal microRNA-451-5p Is a Potential Early Biomarker of Diabetic Nephropathy in Rats
Non-invasive renal signatures can help in serial monitoring of diabetic patients. We tested whether urinary exosomal (UE) microRNA (miR) analysis could non-invasively predict renal pathology in diabetic rats during the course of diabetes. Diabetes mellitus (DM) was induced in male Wistar rats by a single intraperitoneal injection of streptozotocin (STZ, 50 mg/kg body weight). Non-diabetic control (CTRL) rats were injected with vehicle. Insulin (INS) treatment (5U/d, s.c.) was provided to 50% of the DM rats. Urine samples were collected at weeks 3, 6, and 9 following injections and UE prepared. An increase in miR-451-5p and miR-16, observed by pilot small RNA sequencing of UE RNA, was confirmed by quantitative real-time polymerase chain reaction (qPCR) and selected for further study. Subsets of rats were euthanized after 3, 6, and 9 weeks of diabetes for renal pathology analysis, including
determination of the tubulointerstitial fibrotic index (TFI) and glomerulosclerotic index (GI) scores. qPCR showed a substantial rise in miR-451-5p in UE from DM rats during thecourse of diabetes, with a significant rise (median fold change >1000) between 3 and 6 weeks. Moreover, UE miR-451-5p at 6 weeks predicted urine albumin at 9 weeks (r = 0.76).
A delayed but significant rise was also observed for miR-16. In contrast, mean urine albumin only increased 21% between 3 and 6 weeks (non-significant rise), and renal TFI and GI were unchanged till 9 weeks. Renal expression of miR-451-5p and miR-16 (at 10 weeks) did not correlate with urine levels, and moreover, was negatively associated with indices of renal pathology (r�-0.70, p = 0.005 for TFI and r�-0.6, p�0.02 for GI). Overall, a relative elevation in renal miR-451-5p and miR-16 in diabetes appeared protective against diabetes- induced kidney fibrosis; while UE miR-451-5p may hold prognostic value as an earlyand sensitive non-invasive indicator of renal diseas
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